GATE Center for Automotive Fuel Cell Systems at Virginia Tech

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, Douglas

2011-09-30

The Virginia Tech GATE Center for Automotive Fuel Cell Systems (CAFCS) achieved the following objectives in support of the domestic automotive industry: Expanded and updated fuel cell and vehicle technologies education programs; Conducted industry directed research in three thrust areas development and characterization of materials for PEM fuel cells; performance and durability modeling for PEM fuel cells; and fuel cell systems design and optimization, including hybrid and plug-in hybrid fuel cell vehicles; Developed MS and Ph.D. engineers and scientists who are pursuing careers related to fuel cells and automotive applications; Published research results that provide industry with new knowledge whichmore » contributes to the advancement of fuel cell and vehicle systems commercialization. With support from the Dept. of Energy, the CAFCS upgraded existing graduate course offerings; introduced a hands-on laboratory component that make use of Virginia Tech's comprehensive laboratory facilities, funded 15 GATE Fellowships over a five year period; and expanded our program of industry interaction to improve student awareness of challenges and opportunities in the automotive industry. GATE Center graduate students have a state-of-the-art research experience preparing them for a career to contribute to the advancement fuel cell and vehicle technologies.« less

A comparison of low-pressure and supercharged operation of polymer electrolyte membrane fuel cell systems for aircraft applications

NASA Astrophysics Data System (ADS)

Werner, C.; Preiß, G.; Gores, F.; Griebenow, M.; Heitmann, S.

2016-08-01

Multifunctional fuel cell systems are competitive solutions aboard future generations of civil aircraft concerning energy consumption, environmental issues, and safety reasons. The present study compares low-pressure and supercharged operation of polymer electrolyte membrane fuel cells with respect to performance and efficiency criteria. This is motivated by the challenge of pressure-dependent fuel cell operation aboard aircraft with cabin pressure varying with operating altitude. Experimental investigations of low-pressure fuel cell operation use model-based design of experiments and are complemented by numerical investigations concerning supercharged fuel cell operation. It is demonstrated that a low-pressure operation is feasible with the fuel cell device under test, but that its range of stable operation changes between both operating modes. Including an external compressor, it can be shown that the power demand for supercharging the fuel cell is about the same as the loss in power output of the fuel cell due to low-pressure operation. Furthermore, the supercharged fuel cell operation appears to be more sensitive with respect to variations in the considered independent operating parameters load requirement, cathode stoichiometric ratio, and cooling temperature. The results indicate that a pressure-dependent self-humidification control might be able to exploit the potential of low-pressure fuel cell operation for aircraft applications to the best advantage.

Impact of hydrogen SAE J2601 fueling methods on fueling time of light-duty fuel cell electric vehicles

DOE PAGES

Reddi, Krishna; Elgowainy, Amgad; Rustagi, Neha; ...

2017-05-16

Hydrogen fuel cell electric vehicles (HFCEVs) are zero-emission vehicles (ZEVs) that can provide drivers a similar experience to conventional internal combustion engine vehicles (ICEVs), in terms of fueling time and performance (i.e. power and driving range). The Society of Automotive Engineers (SAE) developed fueling protocol J2601 for light-duty HFCEVs to ensure safe vehicle fills while maximizing fueling performance. This study employs a physical model that simulates and compares the fueling performance of two fueling methods, known as the “lookup table” method and the “MC formula” method, within the SAE J2601 protocol. Both the fueling methods provide fast fueling of HFCEVsmore » within minutes, but the MC formula method takes advantage of active measurement of precooling temperature to dynamically control the fueling process, and thereby provides faster vehicle fills. Here, the MC formula method greatly reduces fueling time compared to the lookup table method at higher ambient temperatures, as well as when the precooling temperature falls on the colder side of the expected temperature window for all station types. Although the SAE J2601 lookup table method is the currently implemented standard for refueling hydrogen fuel cell vehicles, the MC formula method provides significant fueling time advantages in certain conditions; these warrant its implementation in future hydrogen refueling stations for better customer satisfaction with fueling experience of HFCEVs.« less

Impact of hydrogen SAE J2601 fueling methods on fueling time of light-duty fuel cell electric vehicles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reddi, Krishna; Elgowainy, Amgad; Rustagi, Neha

Hydrogen fuel cell electric vehicles (HFCEVs) are zero-emission vehicles (ZEVs) that can provide drivers a similar experience to conventional internal combustion engine vehicles (ICEVs), in terms of fueling time and performance (i.e. power and driving range). The Society of Automotive Engineers (SAE) developed fueling protocol J2601 for light-duty HFCEVs to ensure safe vehicle fills while maximizing fueling performance. This study employs a physical model that simulates and compares the fueling performance of two fueling methods, known as the “lookup table” method and the “MC formula” method, within the SAE J2601 protocol. Both the fueling methods provide fast fueling of HFCEVsmore » within minutes, but the MC formula method takes advantage of active measurement of precooling temperature to dynamically control the fueling process, and thereby provides faster vehicle fills. Here, the MC formula method greatly reduces fueling time compared to the lookup table method at higher ambient temperatures, as well as when the precooling temperature falls on the colder side of the expected temperature window for all station types. Although the SAE J2601 lookup table method is the currently implemented standard for refueling hydrogen fuel cell vehicles, the MC formula method provides significant fueling time advantages in certain conditions; these warrant its implementation in future hydrogen refueling stations for better customer satisfaction with fueling experience of HFCEVs.« less

Meta-analysis of Microbial Fuel Cells Using Waste Substrates.

PubMed

Dowdy, F Ryan; Kawakita, Ryan; Lange, Matthew; Simmons, Christopher W

2018-05-01

Microbial fuel cell experimentation using waste streams is an increasingly popular field of study. One obstacle to comparing studies has been the lack of consistent conventions for reporting results such that meta-analysis can be used for large groups of experiments. Here, 134 unique microbial fuel cell experiments using waste substrates were compiled for analysis. Findings include that coulombic efficiency correlates positively with volumetric power density (p < 0.001), negatively with working volume (p < 0.05), and positively with percentage removal of chemical oxygen demand (p < 0.005). Power density in mW/m 2 correlates positively with chemical oxygen demand loading (p < 0.005), and positively with maximum open-circuit voltage (p < 0.05). Finally, single-chamber versus double-chamber reactor configurations differ significantly in maximum open-circuit voltage (p < 0.005). Multiple linear regression to predict either power density or maximum open-circuit voltage produced no significant models due to the amount of multicollinearity between predictor variables. Results indicate that statistically relevant conclusions can be drawn from large microbial fuel cell datasets. Recommendations for future consistency in reporting results following a MIAMFCE convention (Minimum Information About a Microbial Fuel Cell Experiment) are included.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei, Max; Smith, Sarah J.; Sohn, Michael D.

Fuel cells are both a longstanding and emerging technology for stationary and transportation applications, and their future use will likely be critical for the deep decarbonization of global energy systems. As we look into future applications, a key challenge for policy-makers and technology market forecasters who seek to track and/or accelerate their market adoption is the ability to forecast market costs of the fuel cells as technology innovations are incorporated into market products. Specifically, there is a need to estimate technology learning rates, which are rates of cost reduction versus production volume. Unfortunately, no literature exists for forecasting future learningmore » rates for fuel cells. In this paper, we look retrospectively to estimate learning rates for two fuel cell deployment programs: (1) the micro-combined heat and power (CHP) program in Japan, and (2) the Self-Generation Incentive Program (SGIP) in California. These two examples have a relatively broad set of historical market data and thus provide an informative and international comparison of distinct fuel cell technologies and government deployment programs. We develop a generalized procedure for disaggregating experience-curve cost-reductions in order to disaggregate the Japanese fuel cell micro-CHP market into its constituent components, and we derive and present a range of learning rates that may explain observed market trends. Finally, we explore the differences in the technology development ecosystem and market conditions that may have contributed to the observed differences in cost reduction and draw policy observations for the market adoption of future fuel cell technologies. The scientific and policy contributions of this paper are the first comparative experience curve analysis of past fuel cell technologies in two distinct markets, and the first quantitative comparison of a detailed cost model of fuel cell systems with actual market data. The resulting approach is applicable to analyzing other fuel cell markets and other energy-related technologies, and highlights the data needed for cost modeling and quantitative assessment of key cost reduction components.« less

Nonlinear Recurrent Neural Network Predictive Control for Energy Distribution of a Fuel Cell Powered Robot

PubMed Central

Chen, Qihong; Long, Rong; Quan, Shuhai

2014-01-01

This paper presents a neural network predictive control strategy to optimize power distribution for a fuel cell/ultracapacitor hybrid power system of a robot. We model the nonlinear power system by employing time variant auto-regressive moving average with exogenous (ARMAX), and using recurrent neural network to represent the complicated coefficients of the ARMAX model. Because the dynamic of the system is viewed as operating- state- dependent time varying local linear behavior in this frame, a linear constrained model predictive control algorithm is developed to optimize the power splitting between the fuel cell and ultracapacitor. The proposed algorithm significantly simplifies implementation of the controller and can handle multiple constraints, such as limiting substantial fluctuation of fuel cell current. Experiment and simulation results demonstrate that the control strategy can optimally split power between the fuel cell and ultracapacitor, limit the change rate of the fuel cell current, and so as to extend the lifetime of the fuel cell. PMID:24707206

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandler, K.; Eudy, L.

This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

Design of experiments with four-factors for a PEM fuel cell optimization

NASA Astrophysics Data System (ADS)

Olteanu, V.; Pǎtularu, L.; Popescu, C. L.; Popescu, M. O.; Crǎciunescu, A.

2017-07-01

Nowadays, many research efforts are allocated for the development of fuel cells, since they constitute a carbon-free electrical energy generator which can be used for stationary, mobile and portable applications. The maximum value of the delivered power of a fuel cell depends on many factors as: the height of plates' channels, the stoichiometry level of the air flow, the air pressure for the cathode, and of the actual operating electric current density. In this paper, two levels, full four-factors factorial experiment has been designed in order to obtain the appropriate response surface which approximates the maximum delivered power dependence of the above-mentioned factors. The optimum set of the fuel-cell factors which determine the maximum value of the delivered power was determined and a comparison between simulated and measured optimal Power versus Current Density characteristics is given.

Diamond nanoparticles as a support for Pt and PtRu catalysts for direct methanol fuel cells.

PubMed

La-Torre-Riveros, Lyda; Guzman-Blas, Rolando; Méndez-Torres, Adrián E; Prelas, Mark; Tryk, Donald A; Cabrera, Carlos R

2012-02-01

Diamond in nanoparticle form is a promising material that can be used as a robust and chemically stable catalyst support in fuel cells. It has been studied and characterized physically and electrochemically, in its thin film and powder forms, as reported in the literature. In the present work, the electrochemical properties of undoped and boron-doped diamond nanoparticle electrodes, fabricated using the ink-paste method, were investigated. Methanol oxidation experiments were carried out in both half-cell and full fuel cell modes. Platinum and ruthenium nanoparticles were chemically deposited on undoped and boron doped diamond nanoparticles through the use of NaBH(4) as reducing agent and sodium dodecyl benzene sulfonate (SDBS) as a surfactant. Before and after the reduction process, samples were characterized by electron microscopy and spectroscopic techniques. The ink-paste method was also used to prepare the membrane electrode assembly with Pt and Pt-Ru modified undoped and boron-doped diamond nanoparticle catalytic systems, to perform the electrochemical experiments in a direct methanol fuel cell system. The results obtained demonstrate that diamond supported catalyst nanomaterials are promising for methanol fuel cells.

Emerging Fuel Cell Technology Being Developed: Offers Many Benefits to Air Vehicles

NASA Technical Reports Server (NTRS)

Walker, James F.; Civinskas, Kestutis C.

2004-01-01

Fuel cells, which have recently received considerable attention for terrestrial applications ranging from automobiles to stationary power generation, may enable new aerospace missions as well as offer fuel savings, quiet operations, and reduced emissions for current and future aircraft. NASA has extensive experience with fuel cells, having used them on manned space flight systems over four decades. Consequently, the NASA Glenn Research Center has initiated an effort to investigate and develop fuel cell technologies for multiple aerospace applications. Two promising fuel cell types are the proton exchange membrane (PEM) and solid oxide fuel cell (SOFC). PEM technology, first used on the Gemini spacecraft in the sixties, remained unutilized thereafter until the automotive industry recently recognized the potential. PEM fuel cells are low-temperature devices offering quick startup time but requiring relatively pure hydrogen fuel. In contrast, SOFCs operate at high temperatures and tolerate higher levels of impurities. This flexibility allows SOFCs to use hydrocarbon fuels, which is an important factor considering our current liquid petroleum infrastructure. However, depending on the specific application, either PEM or SOFC can be attractive. As only NASA can, the Agency is pursuing fuel cell technology for civil uninhabited aerial vehicles (UAVs) because it offers enhanced scientific capabilities, including enabling highaltitude, long-endurance missions. The NASA Helios aircraft demonstrated altitudes approaching 100,000 ft using solar power in 2001, and future plans include the development of a regenerative PEM fuel cell to provide nighttime power. Unique to NASA's mission, the high-altitude aircraft application requires the PEM fuel cell to operate on pure oxygen, instead of the air typical of terrestrial applications.

Hickam Air Force Base Fuel Cell Vehicles : Early Implementation Experience

DOT National Transportation Integrated Search

2008-07-01

This report describes operations at Alameda-Contra Costa Transit District (AC Transit) for three prototype fuel cell buses and six diesel buses operating from the same location. This is the third evaluation report for this site, and it describes new ...

Electricity generation in microbial fuel cells using neutral red as an electronophore

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, D.H.; Zeikus, J.G.

2000-04-01

Neutral red (NR) was utilized as an electron mediator in microbial fuel cells consuming glucose to study both its efficiency during electricity generation and its role in altering anaerobic growth and metabolism of Escherichia coli and Actinobacillus succinogenes. A study of chemical fuel cells in which NADH, NR, and ferricyanide were the electron donor, the electronophore, and the electron acceptor, respectively, showed that electrical current produced from NADH was proportional to the concentration of NADH. Fourfold more current was produced from NADH in chemical fuel cells when NR was the electron mediator than when thionin was the electron mediator. Inmore » microbial fuel cells in which E. coli resting cells were used the amount of current produced from glucose when NR was the electron mediator was 10-fold more than the amount produced when thionin was the electron mediator. The amount of electrical energy generated and the amount of current produced from glucose in NR-mediated microbial fuel cells containing either E. coli or A. succinogenes were about 10- and 2-fold greater, respectively, when resting cells were used than when growing cells were used. Cell growth was inhibited substantially when these microbial fuel cells were making current, and more oxidized end products were formed under these conditions. When sewage sludge was used in the fuel cell, stable and equivalent levels of current were obtained with glucose, as observed in the pure-culture experiments. These results suggest that NR is better than other electron mediators used in microbial fuel cells and that sludge production can be decreased while electricity is produced in fuel cells. Their results are discussed in relation to factors that may improve the relatively low electrical efficiencies obtained with microbial fuel cells.« less

Three-dimensional computational fluid dynamics modelling and experimental validation of the Jülich Mark-F solid oxide fuel cell stack

NASA Astrophysics Data System (ADS)

Nishida, R. T.; Beale, S. B.; Pharoah, J. G.; de Haart, L. G. J.; Blum, L.

2018-01-01

This work is among the first where the results of an extensive experimental research programme are compared to performance calculations of a comprehensive computational fluid dynamics model for a solid oxide fuel cell stack. The model, which combines electrochemical reactions with momentum, heat, and mass transport, is used to obtain results for an established industrial-scale fuel cell stack design with complex manifolds. To validate the model, comparisons with experimentally gathered voltage and temperature data are made for the Jülich Mark-F, 18-cell stack operating in a test furnace. Good agreement is obtained between the model and experiment results for cell voltages and temperature distributions, confirming the validity of the computational methodology for stack design. The transient effects during ramp up of current in the experiment may explain a lower average voltage than model predictions for the power curve.

Modelling and validation of Proton exchange membrane fuel cell (PEMFC)

NASA Astrophysics Data System (ADS)

Mohiuddin, A. K. M.; Basran, N.; Khan, A. A.

2018-01-01

This paper is the outcome of a small scale fuel cell project. Fuel cell is an electrochemical device that converts energy from chemical reaction to electrical work. Proton Exchange Membrane Fuel Cell (PEMFC) is one of the different types of fuel cell, which is more efficient, having low operational temperature and fast start up capability results in high energy density. In this study, a mathematical model of 1.2 W PEMFC is developed and simulated using MATLAB software. This model describes the PEMFC behaviour under steady-state condition. This mathematical modeling of PEMFC determines the polarization curve, power generated, and the efficiency of the fuel cell. Simulation results were validated by comparing with experimental results obtained from the test of a single PEMFC with a 3 V motor. The performance of experimental PEMFC is little lower compared to simulated PEMFC, however both results were found in good agreement. Experiments on hydrogen flow rate also been conducted to obtain the amount of hydrogen consumed to produce electrical work on PEMFC.

National Fuel Cell Bus Program: Accelerated Testing Evaluation Report #2, Alameda-Contra Costa Transit District (AC Transit) and Appendices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eudy, L.; Chandler, K.

2010-06-01

This is an evaluation of hydrogen fuel cell transit buses operating at AC Transit in revenue service since March 20, 2006, comparing similar diesel buses operating from the same depot. It covers November 2007 through February 2010. Results include implementation experience, fueling station operation, evaluation results at AC Transit (bus usage, availability, fuel economy, maintenance costs, and road calls), and a summary of achievements and challenges encountered during the demonstration.

Hydrogen-oxygen proton-exchange membrane fuel cells and electrolyzers

NASA Technical Reports Server (NTRS)

Baldwin, R.; Pham, M.; Leonida, A.; Mcelroy, J.; Nalette, T.

1989-01-01

Hydrogen-oxygen solid polymer electrolyte (SPE) fuel cells and SPE electrolyzers (products of Hamilton Standard) both use a Proton-Exchange Membrane (PEM) as the sole electrolyte. These solid electrolyte devices have been under continuous development for over 30 years. This experience has resulted in a demonstrated ten-year SPE cell life capability under load conditions. Ultimate life of PEM fuel cells and electrolyzers is primarily related to the chemical stability of the membrane. For perfluorocarbon proton exchange membranes an accurate measure of the membrane stability is the fluoride loss rate. Millions of cell hours have contributed to establishing a relationship between fluoride loss rates and average expected ultimate cell life. This relationship is shown. Several features have been introduced into SPE fuel cells and SPE electrolyzers such that applications requiring greater than or equal to 100,000 hours of life can be considered. Equally important as the ultimate life is the voltage stability of hydrogen-oxygen fuel cells and electrolyzers. Here again the features of SPE fuel cells and SPE electrolyzers have shown a cell voltage stability in the order of 1 microvolt per hour. That level of stability has been demonstrated for tens of thousands of hours in SPE fuel cells at up to 500 amps per square foot (ASF) current density.

Differential Die-Away Instrument: Report on Fuel Assembly Mock-up Measurements with Neutron Generator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goodsell, Alison Victoria; Swinhoe, Martyn Thomas; Henzl, Vladimir

2014-09-18

Fresh fuel experiments for the differential die-away (DDA) project were performed using a DT neutron generator, a 15x15 PWR fuel assembly, and nine 3He detectors in a water tank inside of a shielded cell at Los Alamos National Laboratory (LANL). Eight different fuel enrichments were created using low enriched (LEU) and depleted uranium (DU) dioxide fuel rods. A list-mode data acquisition system recorded the time-dependent signal and analysis of the DDA signal die-away time was performed. The die-away time depended on the amount of fissile material in the fuel assembly and the position of the detector. These experiments were performedmore » in support of the spent nuclear fuel Next Generation Safeguards Initiative DDA project. Lessons learned from the fresh fuel DDA instrument experiments and simulations will provide useful information to the spent fuel project.« less

Evaluation of Cathode Air Flow Transients in a SOFC/GT Hybrid System Using Hardware in the Loop Simulation.

PubMed

Zhou, Nana; Yang, Chen; Tucker, David

2015-02-01

Thermal management in the fuel cell component of a direct fired solid oxide fuel cell gas turbine (SOFC/GT) hybrid power system can be improved by effective management and control of the cathode airflow. The disturbances of the cathode airflow were accomplished by diverting air around the fuel cell system through the manipulation of a hot-air bypass valve in open loop experiments, using a hardware-based simulation facility designed and built by the U.S. Department of Energy, National Energy Technology Laboratory (NETL). The dynamic responses of the fuel cell component and hardware component of the hybrid system were studied in this paper.

Active water management at the cathode of a planar air-breathing polymer electrolyte membrane fuel cell using an electroosmotic pump

NASA Astrophysics Data System (ADS)

Fabian, T.; O'Hayre, R.; Litster, S.; Prinz, F. B.; Santiago, J. G.

In a typical air-breathing fuel cell design, ambient air is supplied to the cathode by natural convection and dry hydrogen is supplied to a dead-ended anode. While this design is simple and attractive for portable low-power applications, the difficulty in implementing effective and robust water management presents disadvantages. In particular, excessive flooding of the open-cathode during long-term operation can lead to a dramatic reduction of fuel cell power. To overcome this limitation, we report here on a novel air-breathing fuel cell water management design based on a hydrophilic and electrically conductive wick in conjunction with an electroosmotic (EO) pump that actively pumps water out of the wick. Transient experiments demonstrate the ability of the EO-pump to "resuscitate" the fuel cell from catastrophic flooding events, while longer term galvanostatic measurements suggest that the design can completely eliminate cathode flooding using less than 2% of fuel cell power, and lead to stable operation with higher net power performance than a control design without EO-pump. This demonstrates that active EO-pump water management, which has previously only been demonstrated in forced-convection fuel cell systems, can also be applied effectively to miniaturized (<5 W) air-breathing fuel cell systems.

Serotonin (5-HT) released by activated white blood cells in a biological fuel cell provide a potential energy source for electricity generation.

PubMed

Justin, Gusphyl A; Sun, Mingui; Zhang, Yingze; Cui, X Tracy; Sclabassi, Robert

2006-01-01

Previous studies by our group have demonstrated the ability of white blood cells to generate small electrical currents, on the order of 1-3 microA/cm(2), when placed at the anode compartment of a proton exchange membrane (PEM) biological fuel cell. In this research study, an electrochemical technique is used to further investigate the electron transfer ability of activated white blood cells at interfacing electrodes in an attempt to elucidate the mechanism of electron transfer in the original biological fuel cell experiments. Cyclic voltammograms were obtained for human white blood cells using a three-electrode system. The working and counter electrodes were made from carbon felt and platinum, respectively, while the reference was a saturated calomel electrode (SCE). Oxidation peaks were observed at an average potential of 363 mV vs. SCE for the PMA/ionomycin activated white blood cells in glucose solution. However a corresponding reduction peak was not observed, suggesting irreversibility of the redox reaction. The cyclic voltammograms recorded for the white blood cells bear very close similarities to those of the neurotransmitter serotonin (5-HT). Serotonin released by white blood cells into the extracellular environment may be irreversibly oxidized at the working electrode in the cyclic voltammetry experiments and at the PEM biological fuel cell anode in our earlier electrochemical cell studies.

The Microbial Fuel Cell as an Education Tool

ERIC Educational Resources Information Center

Dewan, Alim; Van Wie, Bernard; Beyenal, Haluk; Lewandowski, Zbigniew

2010-01-01

Many chemical engineering programs offer courses from a variety of disciplines to teach their students multidisciplinary concepts, but often these courses lack appropriate tools for linking newly learned concepts to principles learned in the core courses. This paper describes our experience of incorporating a microbial fuel cell education module…

Solid oxide fuel cell anode degradation by the effect of hydrogen chloride in stack and single cell environments

NASA Astrophysics Data System (ADS)

Madi, Hossein; Lanzini, Andrea; Papurello, Davide; Diethelm, Stefan; Ludwig, Christian; Santarelli, Massimo; Van herle, Jan

2016-09-01

The poisoning effect by hydrogen chloride (HCl) on state-of-the-art Ni anode-supported solid oxide fuel cells (SOFCs) at 750 °C is evaluated in either hydrogen or syngas fuel. Experiments are performed on single cells and short stacks and HCl concentration in the fuel gas is increased from 1 ppm(v) up to 1000 ppm(v) at different current densities. Characterization methods such as cell voltage monitoring vs. time and electrochemical impedance response analysis (distribution of relaxation times (DRT), equivalent electrical circuit) are used to identify the prevailing degradation mechanism. Single cell experiments revealed that the poisoning is more severe when feeding with hydrogen than with syngas. Performance loss is attributed to the effects of HCl adsorption onto nickel surfaces, which lowered the catalyst activity. Interestingly, in syngas HCl does not affect stack performance even at concentrations up to 500 ppm(v), even when causing severe corrosion of the anode exhaust pipe. Furthermore, post-test analysis suggests that chlorine is present on the nickel particles in the form of adsorbed chlorine, rather than forming a secondary phase of nickel chlorine.

Contact behavior modelling and its size effect on proton exchange membrane fuel cell

NASA Astrophysics Data System (ADS)

Qiu, Diankai; Peng, Linfa; Yi, Peiyun; Lai, Xinmin; Janßen, Holger; Lehnert, Werner

2017-10-01

Contact behavior between the gas diffusion layer (GDL) and bipolar plate (BPP) is of significant importance for proton exchange membrane fuel cells. Most current studies on contact behavior utilize experiments and finite element modelling and focus on fuel cells with graphite BPPs, which lead to high costs and huge computational requirements. The objective of this work is to build a more effective analytical method for contact behavior in fuel cells and investigate the size effect resulting from configuration alteration of channel and rib (channel/rib). Firstly, a mathematical description of channel/rib geometry is outlined in accordance with the fabrication of metallic BPP. Based on the interface deformation characteristic and Winkler surface model, contact pressure between BPP and GDL is then calculated to predict contact resistance and GDL porosity as evaluative parameters of contact behavior. Then, experiments on BPP fabrication and contact resistance measurement are conducted to validate the model. The measured results demonstrate an obvious dependence on channel/rib size. Feasibility of the model used in graphite fuel cells is also discussed. Finally, size factor is proposed for evaluating the rule of size effect. Significant increase occurs in contact resistance and porosity for higher size factor, in which channel/rib width decrease.

Study of Plasma Behavior during ECRH Injection in the GAMMA 10 SMBI Experiments

NASA Astrophysics Data System (ADS)

Maidul Islam, Md.; Nakashima, Yousuke; Kobayashi, Shinji; Nishino, Nobuhiro; Ichimura, Kazuya; Iijima, Takaaki; Shahinul Islam, Md.; Yokodo, Takayuki; Lee, Guanyi; Yoshimoto, Tsubasa; Yamashita, Sotaro; Yoshikawa, Masayuki; Kohagura, Junko; Hirata, Mafumi; Minami, Ryutaro; Kariya, Tsuyoshi; Ikezoe, Ryuya; Ichimura, Makoto; Sakamoto, Mizuki; Imai, Tsuyoshi

2018-01-01

Establishment of fueling system is one of the critical issues for the future fusion reactors. Fueling experiment supersonic molecular beam injection (SMBI) have been carried out in the central-cell of GAMMA 10. In GAMMA 10, electron cyclotron resonance heating (ECRH) is used at plug/barrier-cells for the formation of the axial confining potential. Recently, ECRH was applied during SMBI to plug the loss particles and increased the plasma density in the central-cell compared to without ECRH. This result suggests that the particles are confined during SMBI due to the injection of ECRH at plug/barrier-cells in GAMMA 10.

Solid-state proton conductors

NASA Astrophysics Data System (ADS)

Jewulski, J. R.; Osif, T. L.; Remick, R. J.

1990-12-01

The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium temperature SSPC development, electrodes for moderate temperature (SSPC) fuel cell, basic material and measurement techniques applicable for SSPC development, modeling, and optimization studies. Correlation and optimization studies are described which include correlation studies on proton conduction and oxide cathode optimization for the SSPC fuel cell. Experiments with the SSPC fuel cells are presented which include the fabrication of the electrolyte disks, apparatus for conducting measurements, the strontium-cerium based electrolyte, the barium-cerium based electrolyte with solid foil electrodes, the barium-cerium based electrolyte with porous electrodes, and conduction mechanisms.

Study of ceria-carbonate nanocomposite electrolytes for low-temperature solid oxide fuel cells.

PubMed

Fan, L; Wang, C; Di, J; Chen, M; Zheng, J; Zhu, B

2012-06-01

Composite and nanocomposite samarium doped ceria-carbonates powders were prepared by solid-state reaction, citric acid-nitrate combustion and modified nanocomposite approaches and used as electrolytes for low temperature solid oxide fuel cells. X-ray Diffraction, Scanning Electron Microscope, low-temperature Nitrogen Adsorption/desorption Experiments, Electrochemical Impedance Spectroscopy and fuel cell performance test were employed in characterization of these materials. All powders are nano-size particles with slight aggregation and carbonates are amorphous in composites. Nanocomposite electrolyte exhibits much lower impedance resistance and higher ionic conductivity than those of the other electrolytes at lower temperature. Fuel cell using the electrolyte prepared by modified nanocomposite approach exhibits the best performance in the whole operation temperature range and achieves a maximum power density of 839 mW cm(-2) at 600 degrees C with H2 as fuel. The excellent physical and electrochemical performances of nanocomposite electrolyte make it a promising candidate for low-temperature solid oxide fuel cells.

Outward electron transfer by Saccharomyces cerevisiae monitored with a bi-cathodic microbial fuel cell-type activity sensor.

PubMed

Ducommun, Raphaël; Favre, Marie-France; Carrard, Delphine; Fischer, Fabian

2010-03-01

A Janus head-like bi-cathodic microbial fuel cell was constructed to monitor the electron transfer from Saccharomyces cerevisiae to a woven carbon anode. The experiments were conducted during an ethanol cultivation of 170 g/l glucose in the presence and absence of yeast-peptone medium. First, using a basic fuel-cell type activity sensor, it was shown that yeast-peptone medium contains electroactive compounds. For this purpose, 1% solutions of soy peptone and yeast extract were subjected to oxidative conditions, using a microbial fuel cell set-up corresponding to a typical galvanic cell, consisting of culture medium in the anodic half-cell and 0.5 M K(3)Fe(CN)(6) in the cathodic half-cell. Second, using a bi-cathodic microbial fuel cell, it was shown that electrons were transferred from yeast cells to the carbon anode. The participation of electroactive compounds in the electron transport was separated as background current. This result was verified by applying medium-free conditions, where only glucose was fed, confirming that electrons are transferred from yeast cells to the woven carbon anode. Knowledge about the electron transfer through the cell membrane is of importance in amperometric online monitoring of yeast fermentations and for electricity production with microbial fuel cells. Copyright (c) 2009 John Wiley & Sons, Ltd.

Proton dynamics of phosphoric acid in HT-PEFCs: Towards "operando" experiments

NASA Astrophysics Data System (ADS)

Khaneft, Marina; Shuai, Liu; Lin, Yu; Janßen, Holger; Lüke, Wiebke; Zorn, Reiner; Ivanova, Oxana; Radulescu, Aurel; Holderer, Olaf; Lehnert, Werner

2018-05-01

High Temperature Polymer Electrolyte Fuel Cells (HT-PEFCs) have been studied with quasielastic neutron scattering, which gives access to the proton diffusion in the fuel cell on local length- and timescales. So far, the different components such as the proton conducting membrane and the electrode layers have been studied separately. Here we show that also operating fuel cells can be investigated and the proton diffusion can be measured under real working conditions. The proton diffusion during power production is compared to that "at rest" but at elevated temperatures.

Electricity Generation in Microbial Fuel Cells Using Neutral Red as an Electronophore

PubMed Central

Park, Doo Hyun; Zeikus, J. Gregory

2000-01-01

Neutral red (NR) was utilized as an electron mediator in microbial fuel cells consuming glucose to study both its efficiency during electricity generation and its role in altering anaerobic growth and metabolism of Escherichia coli and Actinobacillus succinogenes. A study of chemical fuel cells in which NADH, NR, and ferricyanide were the electron donor, the electronophore, and the electron acceptor, respectively, showed that electrical current produced from NADH was proportional to the concentration of NADH. Fourfold more current was produced from NADH in chemical fuel cells when NR was the electron mediator than when thionin was the electron mediator. In microbial fuel cells in which E. coli resting cells were used the amount of current produced from glucose when NR was the electron mediator (3.5 mA) was 10-fold more than the amount produced when thionin was the electron mediator (0.4 mA). The amount of electrical energy generated (expressed in joules per mole of substrate) and the amount of current produced from glucose (expressed in milliamperes) in NR-mediated microbial fuel cells containing either E. coli or A. succinogenes were about 10- and 2-fold greater, respectively, when resting cells were used than when growing cells were used. Cell growth was inhibited substantially when these microbial fuel cells were making current, and more oxidized end products were formed under these conditions. When sewage sludge (i.e., a mixed culture of anaerobic bacteria) was used in the fuel cell, stable (for 120 h) and equivalent levels of current were obtained with glucose, as observed in the pure-culture experiments. These results suggest that NR is better than other electron mediators used in microbial fuel cells and that sludge production can be decreased while electricity is produced in fuel cells. Our results are discussed in relation to factors that may improve the relatively low electrical efficiencies (1.2 kJ/mol) obtained with microbial fuel cells. PMID:10742202

Energizing Engineering Students with Hydrogen Fuel Cell Project

ERIC Educational Resources Information Center

Cannell, Nori; Zavaleta, Dan

2010-01-01

At Desert Vista High School, near Phoenix, Arizona, Perkins Innovation Grant funding is being used to fund a program that is helping to prepare students for careers in engineering by giving them hands-on experience in areas like hydrogen generation and fuel cell utilization. As one enters Dan Zavaleta's automotive and engineering classroom and lab…

Dynamic modeling, experimental evaluation, optimal design and control of integrated fuel cell system and hybrid energy systems for building demands

NASA Astrophysics Data System (ADS)

Nguyen, Gia Luong Huu

Fuel cells can produce electricity with high efficiency, low pollutants, and low noise. With the advent of fuel cell technologies, fuel cell systems have since been demonstrated as reliable power generators with power outputs from a few watts to a few megawatts. With proper equipment, fuel cell systems can produce heating and cooling, thus increased its overall efficiency. To increase the acceptance from electrical utilities and building owners, fuel cell systems must operate more dynamically and integrate well with renewable energy resources. This research studies the dynamic performance of fuel cells and the integration of fuel cells with other equipment in three levels: (i) the fuel cell stack operating on hydrogen and reformate gases, (ii) the fuel cell system consisting of a fuel reformer, a fuel cell stack, and a heat recovery unit, and (iii) the hybrid energy system consisting of photovoltaic panels, fuel cell system, and energy storage. In the first part, this research studied the steady-state and dynamic performance of a high temperature PEM fuel cell stack. Collaborators at Aalborg University (Aalborg, Denmark) conducted experiments on a high temperature PEM fuel cell short stack at steady-state and transients. Along with the experimental activities, this research developed a first-principles dynamic model of a fuel cell stack. The dynamic model developed in this research was compared to the experimental results when operating on different reformate concentrations. Finally, the dynamic performance of the fuel cell stack for a rapid increase and rapid decrease in power was evaluated. The dynamic model well predicted the performance of the well-performing cells in the experimental fuel cell stack. The second part of the research studied the dynamic response of a high temperature PEM fuel cell system consisting of a fuel reformer, a fuel cell stack, and a heat recovery unit with high thermal integration. After verifying the model performance with the obtained experimental data, the research studied the control of airflow to regulate the temperature of reactors within the fuel processor. The dynamic model provided a platform to test the dynamic response for different control gains. With sufficient sensing and appropriate control, a rapid response to maintain the temperature of the reactor despite an increase in power was possible. The third part of the research studied the use of a fuel cell in conjunction with photovoltaic panels, and energy storage to provide electricity for buildings. This research developed an optimization framework to determine the size of each device in the hybrid energy system to satisfy the electrical demands of buildings and yield the lowest cost. The advantage of having the fuel cell with photovoltaic and energy storage was the ability to operate the fuel cell at baseload at night, thus reducing the need for large battery systems to shift the solar power produced in the day to the night. In addition, the dispatchability of the fuel cell provided an extra degree of freedom necessary for unforeseen disturbances. An operation framework based on model predictive control showed that the method is suitable for optimizing the dispatch of the hybrid energy system.

Analysis and optimization of solid oxide fuel cell-based auxiliary power units using a generic zero-dimensional fuel cell model

NASA Astrophysics Data System (ADS)

Göll, S.; Samsun, R. C.; Peters, R.

Fuel-cell-based auxiliary power units can help to reduce fuel consumption and emissions in transportation. For this application, the combination of solid oxide fuel cells (SOFCs) with upstream fuel processing by autothermal reforming (ATR) is seen as a highly favorable configuration. Notwithstanding the necessity to improve each single component, an optimized architecture of the fuel cell system as a whole must be achieved. To enable model-based analyses, a system-level approach is proposed in which the fuel cell system is modeled as a multi-stage thermo-chemical process using the "flowsheeting" environment PRO/II™. Therein, the SOFC stack and the ATR are characterized entirely by corresponding thermodynamic processes together with global performance parameters. The developed model is then used to achieve an optimal system layout by comparing different system architectures. A system with anode and cathode off-gas recycling was identified to have the highest electric system efficiency. Taking this system as a basis, the potential for further performance enhancement was evaluated by varying four parameters characterizing different system components. Using methods from the design and analysis of experiments, the effects of these parameters and of their interactions were quantified, leading to an overall optimized system with encouraging performance data.

Experience curve development and cost reduction disaggregation for fuel cell markets in Japan and the US

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei, Max; Smith, Sarah J.; Sohn, Michael D.

Technology learning rates can be dynamic quantities as a technology moves from early development to piloting and from low volume manufacturing to high volume manufacturing. This work describes a generalizable technology analysis approach for disaggregating observed technology cost reductions and presents results of this approach for one specific case study (micro-combined heat and power fuel cell systems in Japan). We build upon earlier reports that combine discussion of fuel cell experience curves and qualitative discussion of cost components by providing greater detail on the contributing mechanisms to observed cost reductions, which were not quantified in earlier reports. Greater standardization ismore » added to the analysis approach, which can be applied to other technologies. This paper thus provides a key linkage that has been missing from earlier literature on energy-related technologies by integrating the output of earlier manufacturing cost studies with observed learning rates to quantitatively estimate the different components of cost reduction including economies of scale and cost reductions due to product performance and product design improvements. This work also provides updated fuel cell technology price versus volume trends from the California Self-Generation Incentive Program, including extensive data for solid-oxide fuel cells (SOFC) reported here for the first time. The Japanese micro-CHP market is found to have a learning rate of 18% from 2005 to 2015, while larger SOFC fuel cell systems (200 kW and above) in the California market are found to have a flat (near-zero) learning rate, and these are attributed to a combination of exogenous, market, and policy factors.« less

Space Electrochemical Research and Technology Conference, 2nd, Cleveland, OH, Apr. 11-13, 1989, Proceedings

NASA Technical Reports Server (NTRS)

O'Donnell, Patricia M. (Editor)

1990-01-01

Attention is given to topics of advanced concepts, hydrogen-oxygen fuel cells and electrolyzers, nickel electrodes, and advanced rechargeable batteries. Papers are presented on human exploration mission studies, advanced rechargeable sodium batteries with novel cathodes, advanced double-layer capacitors, recent advances in solid-polymer electrolyte fuel cell technology with low platinum loading electrodes, electrocatalysts for oxygen electrodes in fuel cells and water electrolyzers for space applications, and the corrosion testing of candidates for the alkaline fuel cell cathode. Other papers are on a structural comparison of nickel electodes and precursor phases, the application of electrochemical impedance spectroscopy for characterizing the degradation of Ni(OH)2/NiOOH electrodes, advances in lightweight nickel electrode technology, multimission nickel-hydrogen battery cell for the 1990s, a sodium-sulfur battery flight experiment definition study, and advances in ambient-temperature secondary lithium cells.

Diesel fuel to dc power: Navy & Marine Corps Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bloomfield, D.P.

1996-12-31

During the past year Analytic Power has tested fuel cell stacks and diesel fuel processors for US Navy and Marine Corps applications. The units are 10 kW demonstration power plants. The USN power plant was built to demonstrate the feasibility of diesel fueled PEM fuel cell power plants for 250 kW and 2.5 MW shipboard power systems. We designed and tested a ten cell, 1 kW USMC substack and fuel processor. The complete 10 kW prototype power plant, which has application to both power and hydrogen generation, is now under construction. The USN and USMC fuel cell stacks have beenmore » tested on both actual and simulated reformate. Analytic Power has accumulated operating experience with autothermal reforming based fuel processors operating on sulfur bearing diesel fuel, jet fuel, propane and natural gas. We have also completed the design and fabrication of an advanced regenerative ATR for the USMC. One of the significant problems with small fuel processors is heat loss which limits its ability to operate with the high steam to carbon ratios required for coke free high efficiency operation. The new USMC unit specifically addresses these heat transfer issues. The advances in the mill programs have been incorporated into Analytic Power`s commercial units which are now under test.« less

Hydrogen Storage Experiments for an Undergraduate Laboratory Course--Clean Energy: Hydrogen/Fuel Cells

ERIC Educational Resources Information Center

Bailey, Alla; Andrews, Lisa; Khot, Ameya; Rubin, Lea; Young, Jun; Allston, Thomas D.; Takacs, Gerald A.

2015-01-01

Global interest in both renewable energies and reduction in emission levels has placed increasing attention on hydrogen-based fuel cells that avoid harm to the environment by releasing only water as a byproduct. Therefore, there is a critical need for education and workforce development in clean energy technologies. A new undergraduate laboratory…

In situ observations of water production and distribution in an operating H2/O2 PEM fuel cell assembly using 1H NMR microscopy.

PubMed

Feindel, Kirk W; LaRocque, Logan P-A; Starke, Dieter; Bergens, Steven H; Wasylishen, Roderick E

2004-09-22

Proton NMR imaging was used to investigate in situ the distribution of water in a polymer electrolyte membrane fuel cell operating on H2 and O2. In a single experiment, water was monitored in the gas flow channels, the membrane electrode assembly, and in the membrane surrounding the catalysts. Radial gradient diffusion removes water from the catalysts into the surrounding membrane. This research demonstrates the strength of 1H NMR microscopy as an aid for designing fuel cells to optimize water management.

Power conversion and control methods for renewable energy sources

NASA Astrophysics Data System (ADS)

Yu, Dachuan

2005-07-01

In recent years, there has been an increase in the use of renewable energy due to the growing concern over the pollution caused by fossil-fuel-based energy. Renewable energy sources, such as photovoltaic (PV) and fuel cell, can be used to enhance the safety, reliability, sustainability, and transmission efficiency of a power system. This dissertation focuses on the power conversion and control for two major renewable-energy sources: PV and fuel cell. Firstly, a current-based, maximum power-point tracking (MPPT) algorithm is proposed for PV energy. An economical converter system using the above scheme for converting the output from PV panels into 60 Hz AC voltage is developed and built. Secondly, a novel circuit model for the Proton Exchange Membrane (PEM) fuel-cell stack that is useful in the design and analysis of fuel-cell-based power systems is proposed. This Pspice-based model uses elements available in the Pspice library with some modifications to represent both the static and dynamic responses of a PEM fuel-cell module. The accuracy of the model is verified by comparing the simulation and experimental results. Thirdly, a DSP-controlled three-phase induction-motor drive using constant voltage over frequency is built and can be used in a fuel-cell automobile. A hydrogen sensor is used in the drive to both sound an alarm and shut down the inverter trigger pulses through the DSP. Finally, a hybrid power system consisting of PV panels and fuel cell is proposed and built. In the proposed system, PV panels can supply most of the power when the sunlight is available, and the excess power required by the load is supplied by a fuel cell. Load sharing between a fuel cell (FC) and the PV panel is investigated by both simulation and experiments.

Aluminum Hydride as a Fuel Supplement to NanoThermites

DTIC Science & Technology

2014-01-01

nanocomposite thermite based on CuO, Bi2O3, and Fe2O3. Pressure cell and burn tube experiments demonstrated enhancements in absolute pressure...pressurization rate, and burning velocity when micron-scale aluminum hydride was used as a minor fuel component in a nanoaluminum–copper-oxide thermite ...alane, AlH3) replaced nanoaluminum incrementally as a fuel in a nanocomposite thermite based on CuO, Bi2O3, and Fe2O3. Pressure cell and burn tube

Embedded system based on PWM control of hydrogen generator with SEPIC converter

NASA Astrophysics Data System (ADS)

Fall, Cheikh; Setiawan, Eko; Habibi, Muhammad Afnan; Hodaka, Ichijo

2017-09-01

The objective of this paper is to design and to produce a micro electrical plant system based on fuel cell for teaching material-embedded systems in technical vocational training center. Based on this, the student can experience generating hydrogen by fuel cells, controlling the rate of hydrogen generation by the duty ration of single-ended primary-inductor converter(SEPIC), drawing the curve rate of hydrogen to duty ratio, generating electrical power by using hydrogen, and calculating the fuel cell efficiency when it is used as electrical energy generator. This project is of great importance insofar as students will need to acquire several skills to be able to realize it such as continuous DC DC conversion and the scientific concept behind the converter, the regulation of systems with integral proportional controllers, the installation of photovoltaic cells, the use of high-tech sensors, microcontroller programming, object-oriented programming, mastery of the fuel cell syste

The critical pressure drop for the purge process in the anode of a fuel cell

NASA Astrophysics Data System (ADS)

Yu, Xiao; Pingwen, Ming; Ming, Hou; Baolian, Yi; Shao, Zhi-Gang

Purge operation is an effective way to remove the accumulated liquid water in the anode of proton exchange membrane fuel cells (PEMFCs). This paper studies the phenomenon of the two-phase flow as well as the pressure drop fluctuation inside the flow field of a single cell during the purge process. The flow patterns are identified as intermittent purge and annular purge, and the two purge processes are contrastively analyzed and discussed. The intermittent purge greatly affects the fuel cell performance and thus it is not suitable for the in situ application. The annular purge process requires a higher pressure drop, and the critical pressure drop is calculated from the annular purge model. Furthermore, this value is quantitatively analyzed and validated by experiments. The results show that the annular purge is appropriate for removing liquid water out of the anode in the fuel cell.

Robust adaptive control for a hybrid solid oxide fuel cell system

NASA Astrophysics Data System (ADS)

Snyder, Steven

2011-12-01

Solid oxide fuel cells (SOFCs) are electrochemical energy conversion devices. They offer a number of advantages beyond those of most other fuel cells due to their high operating temperature (800-1000°C), such as internal reforming, heat as a byproduct, and faster reaction kinetics without precious metal catalysts. Mitigating fuel starvation and improving load-following capabilities of SOFC systems are conflicting control objectives. However, this can be resolved by the hybridization of the system with an energy storage device, such as an ultra-capacitor. In this thesis, a steady-state property of the SOFC is combined with an input-shaping method in order to address the issue of fuel starvation. Simultaneously, an overall adaptive system control strategy is employed to manage the energy sharing between the elements as well as to maintain the state-of-charge of the energy storage device. The adaptive control method is robust to errors in the fuel cell's fuel supply system and guarantees that the fuel cell current and ultra-capacitor state-of-charge approach their target values and remain uniformly, ultimately bounded about these target values. Parameter saturation is employed to guarantee boundedness of the parameters. The controller is validated through hardware-in-the-loop experiments as well as computer simulations.

In situ liquid water visualization in polymer electrolyte membrane fuel cells with high resolution synchrotron x-ray radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chevalier, S.; Banerjee, R.; Lee, J.

In this work, we investigated the dominating properties of the porous materials that impact water dynamics in a polymer electrolyte membrane fuel cell (PEMFC). Visualizations of liquid water in an operating PEMFC were performed at the Canadian Light Source. A miniature fuel cell was specifically designed for X-ray imaging investigations, and an in-house image processing algorithm based on the Beer-Lambert law was developed to extract quantities of liquid water thicknesses (cm) from raw X-ray radiographs. The X-ray attenuation coefficient of water at 24 keV was measured with a calibration device to ensure accurate measurements of the liquid water thicknesses. Frommore » this experiment, the through plane distribution of the liquid water in the fuel cell was obtained.« less

Posttest examination of Sodium Loop Safety Facility experiments. [LMFBR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, J.W.

In-reactor, safety experiments performed in the Sodium Loop Safety Facility (SLSF) rely on comprehensive posttest examinations (PTE) to characterize the postirradiation condition of the cladding, fuel, and other test-subassembly components. PTE information and on-line instrumentation data, are analyzed to identify the sequence of events and the severity of the accident for each experiment. Following in-reactor experimentation, the SLSF loop and test assembly are transported to the Hot Fuel Examination Facility (HFEF) for initial disassembly. Goals of the HFEF-phase of the PTE are to retrieve the fuel bundle by dismantling the loop and withdrawing the test assembly, to assess the macro-conditionmore » of the fuel bundle by nondestructive examination techniques, and to prepare the fuel bundle for shipment to the Alpha-Gamma Hot Cell Facility (AGHCF) at Argonne National Laboratory.« less

Palliative effects of H2 on SOFCs operating with carbon containing fuels

NASA Astrophysics Data System (ADS)

Reeping, Kyle W.; Bohn, Jessie M.; Walker, Robert A.

2017-12-01

Chlorine can accelerate degradation of solid oxide fuel cell (SOFC) Ni-based anodes operating on carbon containing fuels through several different mechanisms. However, supplementing the fuel with a small percentage of excess molecular hydrogen effectively masks the degradation to the catalytic activity of the Ni and carbon fuel cracking reaction reactions. Experiments described in this work explore the chemistry behind the "palliative" effect of hydrogen on SOFCs operating with chlorine-contaminated, carbon-containing fuels using a suite of independent, complementary techniques. Operando Raman spectroscopy is used to monitor carbon accumulation and, by inference, Ni catalytic activity while electrochemical techniques including electrochemical impedance spectroscopy and voltammetry are used to monitor overall cell performance. Briefly, hydrogen not only completely hides degradation observed with chlorine-contaminated carbon-containing fuels, but also actively removes adsorbed chlorine from the surface of the Ni, allowing for the methane cracking reaction to continue, albeit at a slower rate. When hydrogen is removed from the fuel stream the cell fails immediately due to chlorine occupation of methane/biogas reaction sites.

Procuring Stationary Fuel Cells For CHP: A Guide for Federal Facility Decision Makers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stinton, David P; McGervey, Joseph; Curran, Scott

2011-11-01

Federal agency leaders are expressing growing interest in using innovative fuel cell combined heat and power (CHP) technology at their sites, motivated by both executive branch sustainability targets and a desire to lead by example in the transition to a clean energy economy. Fuel cell CHP can deliver reliable electricity and heat with 70% to 85% efficiency. Implementing this technology can be a high efficiency, clean energy solution for agencies striving to meet ambitious sustainability requirements with limited budgets. Fuel cell CHP systems can use natural gas or renewable fuels, such as biogas. Procuring Stationary Fuel Cells for CHP: Amore » Guide for Federal Facility Decision Makers presents an overview of the process for planning and implementing a fuel cell CHP project in a concise, step-by-step format. This guide is designed to help agency leaders turn their interest in fuel cell technology into successful installations. This guide concentrates on larger (100 kW and greater) fuel cell CHP systems and does not consider other fuel cell applications such as cars, forklifts, backup power supplies or small generators (<100 kW). Because fuel cell technologies are rapidly evolving and have high up front costs, their deployment poses unique challenges. The electrical and thermal output of the CHP system must be integrated with the building s energy systems. Innovative financing mechanisms allow agencies to make a make versus buy decision to maximize savings. This guide outlines methods that federal agencies may use to procure fuel cell CHP systems with little or no capital investment. Each agency and division, however, has its own set of procurement procedures. This guide was written as a starting point, and it defers to the reader s set of rules if differences exist. The fuel cell industry is maturing, and project developers are gaining experience in working with federal agencies. Technology improvements, cost reductions, and experienced project developers are making fuel cell projects easier to put into service. In this environment, federal decision makers can focus on being smart buyers of fuel cell energy instead of attempting to become experts in fuel cell technology. For agencies that want to pursue a fuel cell CHP this guide presents a four step process for a successful project. 1. Perform a preliminary screening of the energy needs energy costs and incentives. 2. Compare a detailed project plan. 3. Make a financing and contracting decision. 4. Execute the project plan including financing, installation, and operation. The simplest procurement method is designated funding for the outright purchase of the fuel cell CHP system, although this is usually not the most cost-effective option. This guide describes the following financing options: Power purchase agreement Energy savings performance contract Utility energy services contract Enhanced use lease Fuel cell CHP technology can help federal facility managers comply with agency objectives for reducing energy consumption and air pollution emissions. Fuel cells do not generate particulate pollutants, unburned hydrocarbons or the gases that produce acid rain. Fuel cells emit less carbon dioxide (CO2) than other, less efficient technologies and use of renewable fuels can make them carbon neutral. Fuel cell CHP technology can deliver reliable electricity and heat with high efficiency (70% to 85%) in a small physical footprint with little noise, making it a cost-effective option for federal facilities.« less

Electricity production from municipal solid waste using microbial fuel cells.

PubMed

Chiu, H Y; Pai, T Y; Liu, M H; Chang, C A; Lo, F C; Chang, T C; Lo, H M; Chiang, C F; Chao, K P; Lo, W Y; Lo, S W; Chu, Y L

2016-07-01

The organic content of municipal solid waste has long been an attractive source of renewable energy, mainly as a solid fuel in waste-to-energy plants. This study focuses on the potential to use microbial fuel cells to convert municipal solid waste organics into energy using various operational conditions. The results showed that two-chamber microbial fuel cells with carbon felt and carbon felt allocation had a higher maximal power density (20.12 and 30.47 mW m(-2) for 1.5 and 4 L, respectively) than those of other electrode plate allocations. Most two-chamber microbial fuel cells (1.5 and 4 L) had a higher maximal power density than single-chamber ones with corresponding electrode plate allocations. Municipal solid waste with alkali hydrolysis pre-treatment and K3Fe(CN)6 as an electron acceptor improved the maximal power density to 1817.88 mW m(-2) (~0.49% coulomb efficiency, from 0.05-0.49%). The maximal power density from experiments using individual 1.5 and 4 L two-chamber microbial fuel cells, and serial and parallel connections of 1.5 and 4 L two-chamber microbial fuel cells, was found to be in the order of individual 4 L (30.47 mW m(-2)) > serial connection of 1.5 and 4 L (27.75) > individual 1.5 L (20.12) > parallel connection of 1.5 and 4 L (17.04) two-chamber microbial fuel cells . The power density using municipal solid waste microbial fuel cells was compared with information in the literature and discussed. © The Author(s) 2016.

High Temperature Electrolysis using Electrode-Supported Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

J. E. O'Brien; C. M. Stoots

2010-07-01

An experimental study is under way to assess the performance of electrode-supported solid-oxide cells operating in the steam electrolysis mode for hydrogen production. The cells currently under study were developed primarily for the fuel cell mode of operation. Results presented in this paper were obtained from single cells, with an active area of 16 cm2 per cell. The electrolysis cells are electrode-supported, with yttria-stabilized zirconia (YSZ) electrolytes (~10 µm thick), nickel-YSZ steam/hydrogen electrodes (~1400 µm thick), and manganite (LSM) air-side electrodes (~90 µm thick). The purpose of the present study was to document and compare the performance and degradation ratesmore » of these cells in the fuel cell mode and in the electrolysis mode under various operating conditions. Initial performance was documented through a series of DC potential sweeps and AC impedance spectroscopy measurements. Degradation was determined through long-duration testing, first in the fuel cell mode, then in the electrolysis mode over more than 500 hours of operation. Results indicate accelerated degradation rates in the electrolysis mode compared to the fuel cell mode, possibly due to electrode delamination. The paper also includes details of the single-cell test apparatus developed specifically for these experiments.« less

Cerium migration during PEM fuel cell assembly and operation

DOE PAGES

Baker, Andrew M.; Torraco, Dennis; Judge, Elizabeth J.; ...

2015-09-14

Cerium migration between PEM fuel cell components is influenced by potential-driven mobility, ionic diffusion, and gradients in water content. These factors were investigated in ex situ experiments and in operating fuel cells. Potential-induced migration was measured ex situ in hydrated window cells. Cerium-containing MEAs were also fabricated and tested under ASTs. MEA disassembly and subsequent XRF analysis were used to observe rapid cerium migration during cell assembly and operation. During MEA hot pressing, humidification, and low RH operation at OCV, ionic diffusion causes uniform migration from the membrane into the catalyst layers. During high RH operation at OCV, in-plane ceriummore » gradients arise due to variations in water content. These gradients may diminish the scavenging efficacy of cerium by reducing its proximity to generated radicals.« less

First responder training: Supporting commercialization of hydrogen and fuel cell technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barilo, N. F.; Hamilton, J. J.; Weiner, S. C.

A properly trained first responder community is critical to the successful introduction of hydrogen fuel cell applications and their transformation in how we use energy. Providing resources with accurate information and current knowledge is essential to the delivery of effective hydrogen and fuel cell-related first responder training. Furthermore, the California Fuel Cell Partnership and the Pacific Northwest National Laboratory have over 15 years of experience in developing and delivering hydrogen safety-related first responder training materials and programs. A National Hydrogen and Fuel Cell Emergency Response Training Resource was recently released (http://h2tools.org/fr/nt/). This training resource serves the delivery of a varietymore » of training regimens. Associated materials are adaptable for different training formats, ranging from high-level overview presentations to more comprehensive classroom training. Our paper presents what has been learned from the development and delivery of hydrogen safety-related first responder training programs (online, classroom, hands-on) by the respective organizations. We discussed the collaborative strategy being developed for enhancing training materials and methods for greater accessibility based on stakeholder input.« less

First responder training: Supporting commercialization of hydrogen and fuel cell technologies

DOE PAGES

Barilo, N. F.; Hamilton, J. J.; Weiner, S. C.

2017-03-01

A properly trained first responder community is critical to the successful introduction of hydrogen fuel cell applications and their transformation in how we use energy. Providing resources with accurate information and current knowledge is essential to the delivery of effective hydrogen and fuel cell-related first responder training. Furthermore, the California Fuel Cell Partnership and the Pacific Northwest National Laboratory have over 15 years of experience in developing and delivering hydrogen safety-related first responder training materials and programs. A National Hydrogen and Fuel Cell Emergency Response Training Resource was recently released (http://h2tools.org/fr/nt/). This training resource serves the delivery of a varietymore » of training regimens. Associated materials are adaptable for different training formats, ranging from high-level overview presentations to more comprehensive classroom training. Our paper presents what has been learned from the development and delivery of hydrogen safety-related first responder training programs (online, classroom, hands-on) by the respective organizations. We discussed the collaborative strategy being developed for enhancing training materials and methods for greater accessibility based on stakeholder input.« less

Electrolysis Propulsion for Spacecraft Applications

NASA Technical Reports Server (NTRS)

deGroot, Wim A.; Arrington, Lynn A.; McElroy, James F.; Mitlitsky, Fred; Weisberg, Andrew H.; Carter, Preston H., II; Myers, Blake; Reed, Brian D.

1997-01-01

Electrolysis propulsion has been recognized over the last several decades as a viable option to meet many satellite and spacecraft propulsion requirements. This technology, however, was never used for in-space missions. In the same time frame, water based fuel cells have flown in a number of missions. These systems have many components similar to electrolysis propulsion systems. Recent advances in component technology include: lightweight tankage, water vapor feed electrolysis, fuel cell technology, and thrust chamber materials for propulsion. Taken together, these developments make propulsion and/or power using electrolysis/fuel cell technology very attractive as separate or integrated systems. A water electrolysis propulsion testbed was constructed and tested in a joint NASA/Hamilton Standard/Lawrence Livermore National Laboratories program to demonstrate these technology developments for propulsion. The results from these testbed experiments using a I-N thruster are presented. A concept to integrate a propulsion system and a fuel cell system into a unitized spacecraft propulsion and power system is outlined.

The effect of ethanol concentration on the direct ethanol fuel cell performance and products distribution: A study using a single fuel cell/attenuated total reflectance - Fourier transform infrared spectroscopy

NASA Astrophysics Data System (ADS)

Assumpção, M. H. M. T.; Nandenha, J.; Buzzo, G. S.; Silva, J. C. M.; Spinacé, E. V.; Neto, A. O.; De Souza, R. F. B.

2014-05-01

The effect of ethanol concentration on the direct ethanol fuel cell (DEFC) performance and products distribution were studied in situ using a single fuel cell/ATR-FTIR setup. The experiments were performed at 80 °C using commercial Pt3Sn/C as anodic catalyst and the concentrations of ethanol solution were varied from 0.1 to 2.0 mol L-1. An increase in power density was observed with the increase of ethanol concentration to 1.0 mol L-1, while the band intensities analysis in the FTIR spectra revealed an increase of acetic acid/acetaldehyde ratio with the increase of ethanol concentration. Also, from FTIR spectra results, it could be concluded that the acetic acid production follow parallel mechanisms; that is, it does not require the presence of acetaldehyde as an intermediate.

Installation of 200 kW UTC PC-25 Natural Gas Fuel Cell At City of Anaheim Police Station

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dina Predisik

2006-09-15

The City of Anaheim Public Utilities Department (Anaheim) has been providing electric service to Anaheim residents and businesses for over a century. As a city in a high-growth region, identifying sources of reliable energy to meet demand is a constant requirement. Additionally, as more power generation is needed, locating generating stations locally is a difficult proposition and must consider environmental and community impacts. Anaheim believes benefits can be achieved by implementing new distributed generation technologies to supplement central plants, helping keep pace with growing demand for power. If the power is clean, then it can be delivered with minimal environmentalmore » impact. Anaheim started investigating fuel cell technology in 2000 and decided a field demonstration of a fuel cell power plant would help determine how the technology can best serve Anaheim. As a result, Anaheim completed the project under this grant as a way to gain installation and operating experience about fuel cells and fuel cell capabilities. Anaheim also hopes to help others learn more about fuel cells by providing information about this project to the public. Currently, Anaheim has hosted a number of requested tours at the project site, and information about the project can be found on Anaheim Public Utilities RD&D Project website. The Anaheim project was completed in four phases including: research and investigation, purchase, design, and construction. The initial investigative phase started in 2000 and the construction of the project was completed in February 2005. Since acceptance and startup of the fuel cell, the system has operated continuously at an availability of 98.4%. The unit provides an average of about 4,725 kilowatthours a day to the Utilities' generation resources. Anaheim is tracking the operation of the fuel cell system over the five-year life expectancy of the fuel stack and will use the information to determine how fuel cells can serve Anaheim as power generators.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dever, Thomas J.

The project objective was to further assist in the commercialization of fuel cell and H2 technology by building further upon the successful fuel cell lift truck deployments that were executed by LiftOne in 2007, with longer deployments of this technology in real-world applications. We involved facilities management, operators, maintenance personnel, safety groups, and Authorities Having Jurisdiction. LiftOne strived to educate a broad group from many areas of industry and the community as to the benefits of this technology. Included were First Responders from the local areas. We conducted month long deployments with end-users to validate the value proposition and themore » market requirements for fuel cell powered lift trucks. Management, lift truck operators, Authorities Having Jurisdiction and the general public experienced 'hands on' fuel cell experience in the material handling applications. We partnered with Hydrogenics in the execution of the deployment segment of the program. Air Products supplied the compressed H2 gas and the mobile fueler. Data from the Fuel Cell Power Packs and the mobile fueler was sent to the DOE and NREL as required. Also, LiftOne conducted the H2 Education Seminars on a rotating basis at their locations for lift trucks users and for other selected segments of the community over the project's 36 month duration. Executive Summary The technology employed during the deployments program was not new, as the equipment had been used in several previous demos and early adoptions within the material handling industry. This was the case with the new HyPx Series PEM - Fuel Cell Power Packs used, which had been demo'd before during the 2007 Greater Columbia Fuel Cell Challenge. The Air Products HF-150 Fueler was used outdoors during the deployments and had similarly been used for many previous demo programs. The methods used centered on providing this technology as the power for electric sit-down lift trucks at high profile companies operating large fleets. As a long-standing lift truck dealership, LiftOne was able to introduce the fuel cells to such companies in the demanding applications. Accomplishments vs Objectives: We were successful in respect to the stated objectives. The Education Segment's H2 Education Sessions were able to introduce fuel cell technology to many companies and reached the intended broad audience. Also, demos of the lift truck at the sessions as well as the conferences; expos and area events provided great additional exposure. The Deployments were successful in allowing the 6 participating companies to test the 2 fuel cell powered lift trucks in their demanding applications. One of the 6 sites (BMW) eventually adopted over 80 fuel cells from Plug Power. LiftOne was one of the 3 fuel cell demonstrators at BMW for this trial and played a major role in helping to prove the viability and efficiency of this alternative form of energy for BMW. The other 5 companies that participated in the project's deployments were encouraged by the trials and while not converting over to fuel cell power at this time, expressed the desire to revisit acquisition scenarios in the near future as the cost of fuel cells and infrastructure continue to improve. The Education sessions began in March of 2009 at the 7 LiftOne Branches and continued throughout the duration of the project. Attendees came from a large base of lift truck users in North Carolina, South Carolina and Virginia. The sessions were free and invitations were sent out to potential users and companies with intrigue. In addition to the Education content at the sessions (which was offered in a 'H2 101' format), LiftOne was able to demonstrate a working fuel cell powered lift truck, which proved to be a big draw with the 'hands on' experience. LiftOne also demo'd the fuel cell lift trucks at many conferences, expos, professional association meetings, trade shows and 'Green' events in major cities region including Charlotte, Greenville, and Columbia. Such events allowed for H2 Education Material to be presented, and recruit attendees for future sessions. The Deployments began in May '09 and continued through August'10. While the overall results were good, there were some technical problems with the fuel cells at times during the trials. These items are detailed in the attachment provided with this submission. There were never any safety issues during the trials as design features and diagnostic capabilities allowed for quick analysis and field repairs. There were no products developed during this award, as we demo'd existing products. During the project, Tom Dever was able to speak at several panel type discussions and presentations at the NHA/ Fuel Cell & H2 Energy Annual Conference, as well as at the Promat Show in Chicago. Expertise and deployment/ education experiences were imparted during these events. The presentations are included as attachments.« less

A 40-kW fuel cell field test summary utilities activities report

NASA Astrophysics Data System (ADS)

Racine, W. C.; Londos, T. C.

1987-07-01

Forty six 40 kW fuel cell power plants were field tested by 37 host participants at 42 sites in a variety of commercial, light industrial and multifamily residential applications. The participants obtained over 300,000 hours of operating experience with the power plants covering a diverse range of applications for power plant electricity and heat utilization in both single and multiple unit installations.

Low-Pt-Content Anode Catalyst for Direct Methanol Fuel Cells

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram; Whitacre, Jay

2008-01-01

Combinatorial experiments have led to the discovery that a nanophase alloy of Pt, Ru, Ni, and Zr is effective as an anode catalyst material for direct methanol fuel cells. This discovery has practical significance in that the electronic current densities achievable by use of this alloy are comparable or larger than those obtained by use of prior Pt/Ru catalyst alloys containing greater amounts of Pt. Heretofore, the high cost of Pt has impeded the commercialization of direct methanol fuel cells. By making it possible to obtain a given level of performance at reduced Pt content (and, hence, lower cost), the discovery may lead to reduction of the economic impediment to commercialization.

The use of 1H NMR microscopy to study proton-exchange membrane fuel cells.

PubMed

Feindel, Kirk W; Bergens, Steven H; Wasylishen, Roderick E

2006-01-16

To understand proton-exchange membrane fuel cells (PEMFCs) better, researchers have used several techniques to visualize their internal operation. This Concept outlines the advantages of using 1H NMR microscopy, that is, magnetic resonance imaging, to monitor the distribution of water in a working PEMFC. We describe what a PEMFC is, how it operates, and why monitoring water distribution in a fuel cell is important. We will focus on our experience in constructing PEMFCs, and demonstrate how 1H NMR microscopy is used to observe the water distribution throughout an operating hydrogen PEMFC. Research in this area is briefly reviewed, followed by some comments regarding challenges and anticipated future developments.

European opportunities for fuel cell commercialisation

NASA Astrophysics Data System (ADS)

Gibbs, C. E.; Steel, M. C. F.

1992-01-01

The European electricity market is changing. This paper will look at the background to power generation in Europe and highlight the recent factors which have entered the market to promote change. The 1990s seem to offer great possibilities for fuel cell commercialisation. Awareness of environmental problems has never been greater and there is growing belief that fuel cell technology can contribute to solving some of these problems. Issues which have caused the power industry in Europe to re-think its methods of generation include: concern over increasing carbon dioxide emissions and their contribution to the greenhouse effect; increasing SO x and NO x emissions and the damage cause by acid rain; the possibility of adverse effects on health caused by high voltage transmission lines; environmental restrictions to the expansion of hydroelectric schemes; public disenchantment with nuclear power following the Chernobyl accident; avoidance of dependence on imported oil following the Gulf crisis and a desire for fuel flexibility. All these factors are hastening the search for clean, efficient, modular power generators which can be easily sited close to the electricity consumer and operated using a variety of fuels. It is not only the power industry which is changing. A tightening of the legislation concerning emissions from cars is encouraging European auto companies to develop electric vehicles, some of which may be powered by fuel cells. Political changes, such as the opening up of Eastern Europe will also expand the market for low-emission, efficient power plants as attempts are made to develop and clean up that region. Many Europeans organisations are re-awakening their interest, or strengthening their activities, in the area of fuel cells because of the increasing opportunities offered by the European market. While some companies have chosen to buy, test and demonstrate Japanese or American fuel cell stacks with the aim of gaining operational experience and developing European sub-systems, others have chosen to develop their own novel cell technology. This paper will survey the extent of the fuel cell activities in Europe and emphasise the particular markets which fuel cell manufacturers are targeting. Demand for fuel cells in defence and military applications will be the first sector to be commercially viable — European companies such as Siemens, Elenco and VSEL are already marketing AFC or PEM systems for naval and aerospace applications. The small-scale CHP sector is also a likely early market for fuel cell plant. Co-generation fuel cells are of great interest to gas companies like ENAGAS and British Gas looking to promote sales of gas by installing on-site gas-fired generators on their customers' premises. The market for utility scale fuel cell plants is expected to develop later in the decade. The largest demonstration planned for Europe is the 1 MW PAFC for Milan, due to come onstream in 1992. MBB GmbH is considering developing MW-scale MCFC plants with the US company ERC — a 2 MW demonstration is planned for the end of 1993. The potential market for utility fuel cells is large — installation rates could reach 500-1000 MW/year by the turn of the century. Fuel cells will probably not achieve significant use in transport applications in Europe until after the turn of the century unless very stringent emissions legislation for vehicles is introduced. The likely early markets for fuel cells in the transport sector seem to be for delivery and fleet vehicles. Examples of European projects in this area include the Amsterdam city bus project which will use Elenco's AFC technology and Siemens' fork lift truck which will incorporate a PEM fuel cell. Fuel cells also link conveniently with renewable energy systems — coupled with an electrolyser a fuel cell can store solar, wind or wave power. The electrolysis proces is used to generate hydrogen from water at times of surplus energy while the fuel cell consumes hydrogen fuel when demand for power exceeds supply. The SWB solar hydrogen project in Germany is testing PAFC and AFC stacks in this application. Several problems remain before fuel cell technology can fulfil its maximum potential market. For PAFC there is a need to reduce plant capital costs and to verify lifetimes and reliability. KTI's 25 kW demonstration at Delft and the Milan 1 MW plant will increase European knowledge and experience of PAFC plant operation. For MCFC there are materials problems to be solved and work needs to be carried out on the best way to scale up plants. Projects underway in the Netherlands, Germany, Italy and elsewhere should bring Europe to the forefront of MCFC technology. SOFC requires further study in the area of design configurations and fabrication techniques. Research on these aspects is underway in Denmark, Switzerland, Germany, the Netherlands and the UK. For PEM technology work on reducing precious metal loadings and selecting the best polymer membrane is required — an area in which Johnson Matthey is involved. For all fuel cell technologies there needs to be a greater awareness among power suppliers, consumers, legislators and environmentalists of the advantages that fuel cells can offer. The increase in activity among European organisations in developing, demonstrating, testing and optimising fuel cell systems will encourage a greater awareness of the technology and bring commercialisation closer to reality.

Prediction of SOFC Performance with or without Experiments: A Study on Minimum Requirements for Experimental Data

DOE PAGES

Yang, Tao; Sezer, Hayri; Celik, Ismail B.; ...

2015-06-02

In the present paper, a physics-based procedure combining experiments and multi-physics numerical simulations is developed for overall analysis of SOFCs operational diagnostics and performance predictions. In this procedure, essential information for the fuel cell is extracted first by utilizing empirical polarization analysis in conjunction with experiments and refined by multi-physics numerical simulations via simultaneous analysis and calibration of polarization curve and impedance behavior. The performance at different utilization cases and operating currents is also predicted to confirm the accuracy of the proposed model. It is demonstrated that, with the present electrochemical model, three air/fuel flow conditions are needed to producemore » a set of complete data for better understanding of the processes occurring within SOFCs. After calibration against button cell experiments, the methodology can be used to assess performance of planar cell without further calibration. The proposed methodology would accelerate the calibration process and improve the efficiency of design and diagnostics.« less

Analysis of DMFC/battery hybrid power system for portable applications

NASA Astrophysics Data System (ADS)

Lee, Bong-Do; Jung, Doo-Hwan; Ko, Young-Ho

This study was carried out to develop a direct methanol fuel cell (DMFC)/battery hybrid power system used in portable applications. For a portable power system, the DMFC was applied for the main power source at average load and the battery was applied for auxiliary power at overload. Load share characteristics of hybrid power source were analyzed by computational simulation. The connection apparatus between the DMFC and the battery was set and investigated in the real system. Voltages and currents of the load, the battery and the DMFC were measured according to fuel, air and load changes. The relationship between load share characteristic and battery capacity was surveyed. The relationship was also studied in abnormal operation. A DMFC stack was manufactured for this experiment. For the study of the connection characteristics to the fuel cell Pb-acid, Ni-Cd and Ni-MH batteries were tested. The results of this study can be applied to design the interface module of the fuel cell/battery hybrid system and to determine the design requirement in the fuel cell stack for portable applications.

Space processing applications payload equipment study. Volume 2D: SPA supplemental power and heat rejection kit

NASA Technical Reports Server (NTRS)

Hammel, R. L. (Editor); Smith, A. G. (Editor)

1974-01-01

The design and application of a supplementary power and heat rejection kit for the Spacelab are discussed. Two subsystems of electric power and thermal control were analyzed to define the requirements for the power and heat rejection kit (PHRK). Twelve exemplary experiments were defined and power timelines were developed. From these timeline, the experiment requirements for sustained power, peak power, and energy were determined. The electrical power subsystem of the PHRK will consist of two fuel cells, oxygen and hydrogen reactant tank assemblies, water storage tanks, plumbing, cabling, and inverters to convert the nominal 28 volt dc fuel cell output to ac power.

A Terrestrial Microbial Fuel Cell for Powering a Single-Hop Wireless Sensor Network.

PubMed

Zhang, Daxing; Zhu, Yingmin; Pedrycz, Witold; Guo, Yongxian

2016-05-18

Microbial fuel cells (MFCs) are envisioned as one of the most promising alternative renewable energy sources because they can generate electric current continuously while treating waste. Terrestrial Microbial Fuel Cells (TMFCs) can be inoculated and work on the use of soil, which further extends the application areas of MFCs. Energy supply, as a primary influential factor determining the lifetime of Wireless Sensor Network (WSN) nodes, remains an open challenge in sensor networks. In theory, sensor nodes powered by MFCs have an eternal life. However, low power density and high internal resistance of MFCs are two pronounced problems in their operation. A single-hop WSN powered by a TMFC experimental setup was designed and experimented with. Power generation performance of the proposed TMFC, the relationships between the performance of the power generation and the environment temperature, the water content of the soil by weight were measured by experiments. Results show that the TMFC can achieve good power generation performance under special environmental conditions. Furthermore, the experiments with sensor data acquisition and wireless transmission of the TMFC powering WSN were carried out. We demonstrate that the obtained experimental results validate the feasibility of TMFCs powering WSNs.

A Terrestrial Microbial Fuel Cell for Powering a Single-Hop Wireless Sensor Network

PubMed Central

Zhang, Daxing; Zhu, Yingmin; Pedrycz, Witold; Guo, Yongxian

2016-01-01

Microbial fuel cells (MFCs) are envisioned as one of the most promising alternative renewable energy sources because they can generate electric current continuously while treating waste. Terrestrial Microbial Fuel Cells (TMFCs) can be inoculated and work on the use of soil, which further extends the application areas of MFCs. Energy supply, as a primary influential factor determining the lifetime of Wireless Sensor Network (WSN) nodes, remains an open challenge in sensor networks. In theory, sensor nodes powered by MFCs have an eternal life. However, low power density and high internal resistance of MFCs are two pronounced problems in their operation. A single-hop WSN powered by a TMFC experimental setup was designed and experimented with. Power generation performance of the proposed TMFC, the relationships between the performance of the power generation and the environment temperature, the water content of the soil by weight were measured by experiments. Results show that the TMFC can achieve good power generation performance under special environmental conditions. Furthermore, the experiments with sensor data acquisition and wireless transmission of the TMFC powering WSN were carried out. We demonstrate that the obtained experimental results validate the feasibility of TMFCs powering WSNs. PMID:27213346

Hydrogen-Oxygen PEM Regenerative Fuel Cell Energy Storage System

NASA Technical Reports Server (NTRS)

Bents, David J.; Scullin, Vincent J.; Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christopher P.

2005-01-01

An introduction to the closed cycle hydrogen-oxygen polymer electrolyte membrane (PEM) regenerative fuel cell (RFC), recently constructed at NASA Glenn Research Center, is presented. Illustrated with explanatory graphics and figures, this report outlines the engineering motivations for the RFC as a solar energy storage device, the system requirements, layout and hardware detail of the RFC unit at NASA Glenn, the construction history, and test experience accumulated to date with this unit.

Electrolyser and fuel cells, key elements for energy and life support

NASA Astrophysics Data System (ADS)

Bockstahler, Klaus; Funke, Helmut; Lucas, Joachim

Both, Electrolyser and Fuel Cells are key elements for regenerative energy and life support systems. Electrolyser technology is originally intended for oxygen production in manned space habitats and in submarines, through splitting water into hydrogen and oxygen. Fuel cells serve for energy production through the reaction, triggered in the presence of an electrolyte, between a fuel and an oxidant. Now combining both technologies i.e. electrolyser and fuel cell makes it a Regenerative Fuel Cell System (RFCS). In charge mode, i.e. with energy supplied e.g. by solar cells, the electrolyser splits water into hydrogen and oxygen being stored in tanks. In discharge mode, when power is needed but no energy is available, the stored gases are converted in the fuel cell to generate electricity under the formation of water that is stored in tanks. Rerouting the water to the electrolyser makes it a closed-loop i.e. regenerative process. Different electrolyser and fuel cell technologies are being evolved. At Astrium emphasis is put on the development of an RFCS comprised of Fixed Alkaline Electrolyser (FAE) and Fuel Cell (AFC) as such technology offers a high electrical efficiency and thus reduced system weight, which is important in space applications. With increasing power demand and increasing discharge time an RFCS proves to be superior to batteries. Since the early technology development multiple design refinements were done at Astrium, funded by the European Space Agency ESA and the German National Agency DLR as well as based on company internal R and T funding. Today a complete RFCS energy system breadboard is established and the operational behavior of the system is being tested. In parallel the electrolyser itself is subject to design refinement and testing in terms of oxygen production in manned space habitats. In addition essential features and components for process monitoring and control are being developed. The present results and achievements and the dedicated experience gained from testing will be presented, complemented by an outlook on next development steps preparatory to the application of electrolyser and fuel cell technology in human and robotic exploration building blocks.

H2FIRST: A partnership to advance hydrogen fueling station technology driving an optimal consumer experience.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moen, Christopher D.; Dedrick, Daniel E.; Pratt, Joseph William

2014-03-01

The US Department of Energy (DOE) Energy Efficiency and Renewable Energy (EERE) Office of Fuel Cell Technologies Office (FCTO) is establishing the Hydrogen Fueling Infrastructure Research and Station Technology (H2FIRST) partnership, led by the National Renewable Energy Laboratory (NREL) and Sandia National Laboratories (SNL). FCTO is establishing this partnership and the associated capabilities in support of H2USA, the public/private partnership launched in 2013. The H2FIRST partnership provides the research and technology acceleration support to enable the widespread deployment of hydrogen infrastructure for the robust fueling of light-duty fuel cell electric vehicles (FCEV). H2FIRST will focus on improving private-sector economics, safety,more » availability and reliability, and consumer confidence for hydrogen fueling. This whitepaper outlines the goals, scope, activities associated with the H2FIRST partnership.« less

Development and design of experiments optimization of a high temperature proton exchange membrane fuel cell auxiliary power unit with onboard fuel processor

NASA Astrophysics Data System (ADS)

Karstedt, Jörg; Ogrzewalla, Jürgen; Severin, Christopher; Pischinger, Stefan

In this work, the concept development, system layout, component simulation and the overall DOE system optimization of a HT-PEM fuel cell APU with a net electric power output of 4.5 kW and an onboard methane fuel processor are presented. A highly integrated system layout has been developed that enables fast startup within 7.5 min, a closed system water balance and high fuel processor efficiencies of up to 85% due to the recuperation of the anode offgas burner heat. The integration of the system battery into the load management enhances the transient electric performance and the maximum electric power output of the APU system. Simulation models of the carbon monoxide influence on HT-PEM cell voltage, the concentration and temperature profiles within the autothermal reformer (ATR) and the CO conversion rates within the watergas shift stages (WGSs) have been developed. They enable the optimization of the CO concentration in the anode gas of the fuel cell in order to achieve maximum system efficiencies and an optimized dimensioning of the ATR and WGS reactors. Furthermore a DOE optimization of the global system parameters cathode stoichiometry, anode stoichiometry, air/fuel ratio and steam/carbon ratio of the fuel processing system has been performed in order to achieve maximum system efficiencies for all system operating points under given boundary conditions.

Modelling and analysis of a direct ascorbic acid fuel cell

NASA Astrophysics Data System (ADS)

Zeng, Yingzhi; Fujiwara, Naoko; Yamazaki, Shin-ichi; Tanimoto, Kazumi; Wu, Ping

L-Ascorbic acid (AA), also known as vitamin C, is an environmentally-benign and biologically-friendly compound that can be used as an alternative fuel for direct oxidation fuel cells. While direct ascorbic acid fuel cells (DAAFCs) have been studied experimentally, modelling and simulation of these devices have been overlooked. In this work, we develop a mathematical model to describe a DAAFC and validate it with experimental data. The model is formulated by integrating the mass and charge balances, and model parameters are estimated by best-fitting to experimental data of current-voltage curves. By comparing the transient voltage curves predicted by dynamic simulation and experiments, the model is further validated. Various parameters that affect the power generation are studied by simulation. The cathodic reaction is found to be the most significant determinant of power generation, followed by fuel feed concentration and the mass-transfer coefficient of ascorbic acid. These studies also reveal that the power density steadily increases with respect to the fuel feed concentration. The results may guide future development and operation of a more efficient DAAFC.

Residential Fuel Cell Demonstration Handbook

NASA Astrophysics Data System (ADS)

Torrero, E.; McClelland, R.

2002-07-01

This report is a guide for rural electric cooperatives engaged in field testing of equipment and in assessing related application and market issues. Dispersed generation and its companion fuel cell technology have attracted increased interest by rural electric cooperatives and their customers. In addition, fuel cells are a particularly interesting source because their power quality, efficiency, and environmental benefits have now been coupled with major manufacturer development efforts. The overall effort is structured to measure the performance, durability, reliability, and maintainability of these systems, to identify promising types of applications and modes of operation, and to assess the related prospect for future use. In addition, technical successes and shortcomings will be identified by demonstration participants and manufacturers using real-world experience garnered under typical operating environments.

Dynamic Response during PEM Fuel Cell Loading-up

PubMed Central

Pei, Pucheng; Yuan, Xing; Gou, Jun; Li, Pengcheng

2009-01-01

A study on the effects of controlling and operating parameters for a Proton Exchange Membrane (PEM) fuel cell on the dynamic phenomena during the loading-up process is presented. The effect of the four parameters of load-up amplitudes and rates, operating pressures and current levels on gas supply or even starvation in the flow field is analyzed based accordingly on the transient characteristics of current output and voltage. Experiments are carried out in a single fuel cell with an active area of 285 cm2. The results show that increasing the loading-up amplitude can inevitably increase the possibility of gas starvation in channels when a constant flow rate has been set for the cathode; With a higher operating pressure, the dynamic performance will be improved and gas starvations can be relieved. The transient gas supply in the flow channel during two loading-up mode has also been discussed. The experimental results will be helpful for optimizing the control and operation strategies for PEM fuel cells in vehicles.

Gas phase recovery of hydrogen sulfide contaminated polymer electrolyte membrane fuel cells

NASA Astrophysics Data System (ADS)

Kakati, Biraj Kumar; Kucernak, Anthony R. J.

2014-04-01

The effect of hydrogen sulfide (H2S) on the anode of a polymer electrolyte membrane fuel cell (PEMFC) and the gas phase recovery of the contaminated PEMFC using ozone (O3) were studied. Experiments were performed on fuel cell electrodes both in an aqueous electrolyte and within an operating fuel cell. The ex-situ analyses of a fresh electrode; a H2S contaminated electrode (23 μmolH2S cm-2); and the contaminated electrode cleaned with O3 shows that all sulfide can be removed within 900 s at room temperature. Online gas analysis of the recovery process confirms the recovery time required as around 720 s. Similarly, performance studies of an H2S contaminated PEMFC shows that complete rejuvenation occurs following 600-900 s O3 treatment at room temperature. The cleaning process involves both electrochemical oxidation (facilitated by the high equilibrium potential of the O3 reduction process) and direct chemical oxidation of the contaminant. The O3 cleaning process is more efficient than the external polarization of the single cell at 1.6 V. Application of O3 at room temperature limits the amount of carbon corrosion. Room temperature O3 treatment of poisoned fuel cell stacks may offer an efficient and quick remediation method to recover otherwise inoperable systems.

Releasing metal catalysts via phase transition: (NiO)0.05-(SrTi0.8Nb0.2O3)0.95 as a redox stable anode material for solid oxide fuel cells.

PubMed

Xiao, Guoliang; Wang, Siwei; Lin, Ye; Zhang, Yanxiang; An, Ke; Chen, Fanglin

2014-11-26

Donor-doped perovskite-type SrTiO3 experiences stoichiometric changes at high temperatures in different Po2 involving the formation of Sr or Ti-rich impurities. NiO is incorporated into the stoichiometric strontium titanate, SrTi0.8Nb0.2O3-δ (STN), to form an A-site deficient perovskite material, (NiO)0.05-(SrTi0.8Nb0.2O3)0.95 (Ni-STN), for balancing the phase transition. Metallic Ni nanoparticles can be released upon reduction instead of forming undesired secondary phases. This material design introduces a simple catalytic modification method with good compositional control of the ceramic backbones, by which transport property and durability of solid oxide fuel cell anodes are largely determined. Using Ni-STN as anodes for solid oxide fuel cells, enhanced catalytic activity and remarkable stability in redox cycling have been achieved. Electrolyte-supported cells with the cell configuration of Ni-STN-SDC anode, La0.8Sr0.2Ga0.87Mg0.13O3 (LSGM) electrolyte, and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) cathode produce peak power densities of 612, 794, and 922 mW cm(-2) at 800, 850, and 900 °C, respectively, using H2 as the fuel and air as the oxidant. Minor degradation in fuel cell performance resulted from redox cycling can be recovered upon operating the fuel cells in H2. Such property makes Ni-STN a promising regenerative anode candidate for solid oxide fuel cells.

In-situ membrane hydration measurement of proton exchange membrane fuel cells

NASA Astrophysics Data System (ADS)

Lai, Yeh-Hung; Fly, Gerald W.; Clapham, Shawn

2015-01-01

Achieving proper membrane hydration control is one of the most critical aspects of PEM fuel cell development. This article describes the development and application of a novel 50 cm2 fuel cell device to study the in-situ membrane hydration by measuring the through-thickness membrane swelling via an array of linear variable differential transducers. Using this setup either as an air/air (dummy) cell or as a hydrogen/air (operating) cell, we performed a series of hydration and dehydration experiments by cycling the RH of the inlet gas streams at 80 °C. From the linear relationship between the under-the-land swelling and the over-the-channel water content, the mechanical constraint within the fuel cell assembly can suppress the membrane water uptake by 11%-18%. The results from the air/air humidity cycling test show that the membrane can equilibrate within 120 s for all RH conditions and that membrane can reach full hydration at a RH higher than 140% in spite of the use of a liquid water impermeable Carbel MP30Z microporous layer. This result confirms that the U.S. DOE's humidity cycling mechanical durability protocol induces sufficient humidity swings to maximize hygrothermal mechanical stresses. This study shows that the novel experimental technique can provide a robust and accurate means to study the in-situ hydration of thin membranes subject to a wide range of fuel cell conditions.

Mechanical degradation of fuel cell membranes under fatigue fracture tests

NASA Astrophysics Data System (ADS)

Khorasany, Ramin M. H.; Sadeghi Alavijeh, Alireza; Kjeang, Erik; Wang, G. G.; Rajapakse, R. K. N. D.

2015-01-01

The effects of cyclic stresses on the fatigue and mechanical stability of perfluorosulfonic acid (PFSA) membranes are experimentally investigated under standard fuel cell conditions. The experiments are conducted ex-situ by subjecting membrane specimens to cyclic uniaxial tension at controlled temperature and relative humidity. The fatigue lifetime is measured in terms of the number of cycles until ultimate fracture. The results indicate that the membrane fatigue lifetime is a strong function of the applied stress, temperature, and relative humidity. The fatigue life increases exponentially with reduced stresses in all cases. The effect of temperature is found to be more significant than that of humidity, with reduced fatigue life at high temperatures. The maximum membrane strain at fracture is determined to decrease exponentially with increasing membrane lifetime. At a given fatigue life, a membrane exposed to fuel cell conditions is shown to accommodate more plastic strain before fracture than one exposed to room conditions. Overall, the proposed ex-situ membrane fatigue experiment can be utilized to benchmark the fatigue lifetime of new materials in a fraction of the time and cost associated with conventional in-situ accelerated stress testing methods.

An investigation of the typical corrosion parameters used to test polymer electrolyte fuel cell bipolar plate coatings, with titanium nitride coated stainless steel as a case study

NASA Astrophysics Data System (ADS)

Orsi, A.; Kongstein, O. E.; Hamilton, P. J.; Oedegaard, A.; Svenum, I. H.; Cooke, K.

2015-07-01

Stainless steel bipolar plates (BPP) for polymer electrolyte membrane fuel cells (PEMFCs) have good manufacturability, durability and low costs, but inadequate corrosion resistance and elevated interfacial contact resistance (ICR) in the fuel cell environment. Thin film coatings of titanium nitride (TiN) of 1 μm in thickness, were deposited by means of physical vapour deposition (PVD) process on to stainless steel (SS) 316L substrates and were evaluated, in a series of tests, for their level of corrosion protection and ICR. In the ex-situ corrosion tests, variables such as applied potential, experimental duration and pH of the sulphate electrolyte at 80 °C were altered. The ICR values were found to increase after exposure to greater applied potentials and electrolytes of a higher pH. In terms of experimental duration, the ICR increased most rapidly at the beginning of each experiment. It was also found that the oxidation of TiN was accelerated after exposure to electrolytes of a higher pH. When coated BPPs were incorporated into an accelerated fuel cell test, the degradation of the fuel cell cathode resembled the plates that were tested at the highest anodic potential (1.4 VSHE).

Three-dimensional anode engineering for the direct methanol fuel cell

NASA Astrophysics Data System (ADS)

Bauer, A.; Oloman, C. W.; Gyenge, E. L.

Catalyzed graphite felt three-dimensional anodes were investigated in direct methanol fuel cells (DMFCs) operated with sulfuric acid supporting electrolyte. With a conventional serpentine channel flow field the preferred anode thickness was 100 μm, while a novel flow-by anode showed the best performance with a thickness of 200-300 μm. The effects of altering the methanol concentration, anolyte flow rate and operating temperature on the fuel cell superficial power density were studied by full (2 3 + 1) factorial experiments on a cell with anode area of 5 cm 2 and excess oxidant O 2 at 200 kPa(abs). For operation in the flow-by mode with 2 M methanol at 2 cm 3 min -1 and 353 K the peak power density was 2380 W m -2 with a PtRuMo anode catalyst, while a PtRu catalyst yielded 2240 W m -2 under the same conditions.

Electrical start-up for diesel fuel processing in a fuel-cell-based auxiliary power unit

NASA Astrophysics Data System (ADS)

Samsun, Remzi Can; Krupp, Carsten; Tschauder, Andreas; Peters, Ralf; Stolten, Detlef

2016-01-01

As auxiliary power units in trucks and aircraft, fuel cell systems with a diesel and kerosene reforming capacity offer the dual benefit of reduced emissions and fuel consumption. In order to be commercially viable, these systems require a quick start-up time with low energy input. In pursuit of this end, this paper reports an electrical start-up strategy for diesel fuel processing. A transient computational fluid dynamics model is developed to optimize the start-up procedure of the fuel processor in the 28 kWth power class. The temperature trend observed in the experiments is reproducible to a high degree of accuracy using a dual-cell approach in ANSYS Fluent. Starting from a basic strategy, different options are considered for accelerating system start-up. The start-up time is reduced from 22 min in the basic case to 9.5 min, at an energy consumption of 0.4 kW h. Furthermore, an electrical wire is installed in the reformer to test the steam generation during start-up. The experimental results reveal that the generation of steam at 450 °C is possible within seconds after water addition to the reformer. As a result, the fuel processor can be started in autothermal reformer mode using the electrical concept developed in this work.

Ionic Liquids and New Proton Exchange Membranes for Fuel Cells

NASA Technical Reports Server (NTRS)

Belieres, Jean-Philippe

2004-01-01

There is currently a great surge of activity in fuel cell research as laboratories across the world seek to take advantage of the high energy capacity provided by &el cells relative to those of other portable electrochemical power systems. Much of this activity is aimed at high temperature fie1 cells, and a vital component of such &el cells must be the availability of a high temperature stable proton-permeable membrane. NASA Glenn Research Center is greatly involved in developing this technology. Other approaches to the high temperature fuel cell involve the use of single- component or almost-single-component electrolytes that provide a path for protons through the cell. A heavily researched case is the phosphoric acid fuel cell, in which the electrolyte is almost pure phosphoric acid and the cathode reaction produces water directly. The phosphoric acid fie1 cell delivers an open circuit voltage of 0.9 V falling to about 0.7 V under operating conditions at 170 C. The proton transport mechanism is mainly vehicular in character according to the viscosity/conductance relation. Here we describe some Proton Transfer Ionic Liquids (PTILs) with low vapor pressure and high temperature stability that have conductivities of unprecedented magnitude for non-aqueous systems. The first requirement of an ionic liquid is that, contrary to experience with most liquids consisting of ions, it must have a melting point that is not much above room temperature. The limit commonly suggested is 100 C. PTILs constitute an interesting class of non-corrosive proton-exchange electrolyte, which can serve well in high temperature (T = 100 - 250 C) fuel cell applications. We will present cell performance data showing that the open circuit voltage output, and the performance of a simple H2(g)Pt/PTIL/Pt/O2(g) fuel cell may be superior to those of the equivalent phosphoric acid electrolyte fuel cell both at ambient temperature and temperatures up to and above 200 C. My work at NASA Glenn Research Center during this summer is to develop and characterize proton exchange membranes doped with ionic liquids. The main techniques used to characterize these materials are: Impedance Spectroscopy, NMR, DSC, TGA, DMA, IR, and SEM ...

Fractal diffusion in high temperature polymer electrolyte fuel cell membranes

NASA Astrophysics Data System (ADS)

Hopfenmüller, Bernhard; Zorn, Reiner; Holderer, Olaf; Ivanova, Oxana; Lehnert, Werner; Lüke, Wiebke; Ehlers, Georg; Jalarvo, Niina; Schneider, Gerald J.; Monkenbusch, Michael; Richter, Dieter

2018-05-01

The performance of fuel cells depends largely on the proton diffusion in the proton conducting membrane, the core of a fuel cell. High temperature polymer electrolyte fuel cells are based on a polymer membrane swollen with phosphoric acid as the electrolyte, where proton conduction takes place. We studied the proton diffusion in such membranes with neutron scattering techniques which are especially sensitive to the proton contribution. Time of flight spectroscopy and backscattering spectroscopy have been combined to cover a broad dynamic range. In order to selectively observe the diffusion of protons potentially contributing to the ion conductivity, two samples were prepared, where in one of the samples the phosphoric acid was used with hydrogen replaced by deuterium. The scattering data from the two samples were subtracted in a suitable way after measurement. Thereby subdiffusive behavior of the proton diffusion has been observed and interpreted in terms of a model of fractal diffusion. For this purpose, a scattering function for fractal diffusion has been developed. The fractal diffusion dimension dw and the Hausdorff dimension df have been determined on the length scales covered in the neutron scattering experiments.

Real life testing of a Hybrid PEM Fuel Cell Bus

NASA Astrophysics Data System (ADS)

Folkesson, Anders; Andersson, Christian; Alvfors, Per; Alaküla, Mats; Overgaard, Lars

Fuel cells produce low quantities of local emissions, if any, and are therefore one of the most promising alternatives to internal combustion engines as the main power source in future vehicles. It is likely that urban buses will be among the first commercial applications for fuel cells in vehicles. This is due to the fact that urban buses are highly visible for the public, they contribute significantly to air pollution in urban areas, they have small limitations in weight and volume and fuelling is handled via a centralised infrastructure. Results and experiences from real life measurements of energy flows in a Scania Hybrid PEM Fuel Cell Concept Bus are presented in this paper. The tests consist of measurements during several standard duty cycles. The efficiency of the fuel cell system and of the complete vehicle are presented and discussed. The net efficiency of the fuel cell system was approximately 40% and the fuel consumption of the concept bus is between 42 and 48% lower compared to a standard Scania bus. Energy recovery by regenerative braking saves up 28% energy. Bus subsystems such as the pneumatic system for door opening, suspension and brakes, the hydraulic power steering, the 24 V grid, the water pump and the cooling fans consume approximately 7% of the energy in the fuel input or 17% of the net power output from the fuel cell system. The bus was built by a number of companies in a project partly financed by the European Commission's Joule programme. The comprehensive testing is partly financed by the Swedish programme "Den Gröna Bilen" (The Green Car). A 50 kW el fuel cell system is the power source and a high voltage battery pack works as an energy buffer and power booster. The fuel, compressed hydrogen, is stored in two high-pressure stainless steel vessels mounted on the roof of the bus. The bus has a series hybrid electric driveline with wheel hub motors with a maximum power of 100 kW. Hybrid Fuel Cell Buses have a big potential, but there are still many issues to consider prior to full-scale commercialisation of the technology. These are related to durability, lifetime, costs, vehicle and system optimisation and subsystem design. A very important factor is to implement an automotive design policy in the design and construction of all components, both in the propulsion system as well as in the subsystems.

Technology commercialization cost model and component case study

NASA Astrophysics Data System (ADS)

1991-12-01

Fuel cells seem poised to emerge as a clean, efficient, and cost competitive source of fossil fuel based electric power and thermal energy. Sponsors of fuel cell technology development need to determine the validity and the attractiveness of a technology to the market in terms of meeting requirements and providing value which exceeds the total cost of ownership. Sponsors of fuel cell development have addressed this issue by requiring the developers to prepare projections of the future production cost of their fuel cells in commercial quantities. These projected costs, together with performance and life projections, provide a preliminary measure of the total value and cost of the product to the customer. Booz-Allen & Hamilton Inc. and Michael A. Cobb & Company have been retained in several assignments over the years to audit these cost projections. The audits have gone well beyond a simple review of the numbers. They have probed the underlying technical and financial assumptions, the sources of data on material and equipment costs, and explored issues such as the realistic manufacturing yields which can be expected in various processes. Based on the experience gained from these audits, DOE gave Booz-Allen and Michael A. Cobb & company the task to develop a criteria to be used in the execution of future fuel cell manufacturing cost studies. It was thought that such a criteria would make it easier to execute such studies in the future as well as to cause such studies to be more understandable and comparable.

Performance Assessment of Single Electrode-Supported Solid Oxide Cells Operating in the Steam Electrolysis Mode

DOE Office of Scientific and Technical Information (OSTI.GOV)

X. Zhang; J. E. O'Brien; R. C. O'Brien

2011-11-01

An experimental study is under way to assess the performance of electrode-supported solid-oxide cells operating in the steam electrolysis mode for hydrogen production. Results presented in this paper were obtained from single cells, with an active area of 16 cm{sup 2} per cell. The electrolysis cells are electrode-supported, with yttria-stabilized zirconia (YSZ) electrolytes ({approx}10 {mu}m thick), nickel-YSZ steam/hydrogen electrodes ({approx}1400 {mu}m thick), and modified LSM or LSCF air-side electrodes ({approx}90 {mu}m thick). The purpose of the present study is to document and compare the performance and degradation rates of these cells in the fuel cell mode and in the electrolysismore » mode under various operating conditions. Initial performance was documented through a series of voltage-current (VI) sweeps and AC impedance spectroscopy measurements. Degradation was determined through long-term testing, first in the fuel cell mode, then in the electrolysis mode. Results generally indicate accelerated degradation rates in the electrolysis mode compared to the fuel cell mode, possibly due to electrode delamination. The paper also includes details of an improved single-cell test apparatus developed specifically for these experiments.« less

Fuel cell cassette with compliant seal

DOEpatents

Karl, Haltiner, Jr. J.; Anthony, Derose J.; Klotzbach, Darasack C.; Schneider, Jonathan R.

2017-11-07

A fuel cell cassette for forming a fuel cell stack along a fuel cell axis includes a cell retainer, a plate positioned axially to the cell retainer and defining a space axially with the cell retainer, and a fuel cell having an anode layer and a cathode layer separated by an electrolyte layer. The outer perimeter of the fuel cell is positioned in the space between the plate and the cell retainer, thereby retaining the fuel cell and defining a cavity between the cell retainer, the fuel cell, and the plate. The fuel cell cassette also includes a seal disposed within the cavity for sealing the edge of the fuel cell. The seal is compliant at operational temperatures of the fuel cell, thereby allowing lateral expansion and contraction of the fuel cell within the cavity while maintaining sealing at the edge of the fuel cell.

Fuel cell-fuel cell hybrid system

DOEpatents

Geisbrecht, Rodney A.; Williams, Mark C.

2003-09-23

A device for converting chemical energy to electricity is provided, the device comprising a high temperature fuel cell with the ability for partially oxidizing and completely reforming fuel, and a low temperature fuel cell juxtaposed to said high temperature fuel cell so as to utilize remaining reformed fuel from the high temperature fuel cell. Also provided is a method for producing electricity comprising directing fuel to a first fuel cell, completely oxidizing a first portion of the fuel and partially oxidizing a second portion of the fuel, directing the second fuel portion to a second fuel cell, allowing the first fuel cell to utilize the first portion of the fuel to produce electricity; and allowing the second fuel cell to utilize the second portion of the fuel to produce electricity.

Investigation of the Feasibility of Utilizing Gamma Emission Computed Tomography in Evaluating Fission Product Migration in Irradiated TRISO Fuel Experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jason M. Harp; Paul A. Demkowicz

2014-10-01

In the High Temperature Gas-Cooled Reactor (HTGR) the TRISO particle fuel serves as the primary fission product containment. However the large number of TRISO particles present in proposed HTGRs dictates that there will be a small fraction (~10 -4 to 10 -5) of as manufactured and in-pile particle failures that will lead to some fission product release. The matrix material surrounding the TRISO particles in fuel compacts and the structural graphite holding the TRISO particles in place can also serve as sinks for containing any released fission products. However data on the migration of solid fission products through these materialsmore » is lacking. One of the primary goals of the AGR-3/4 experiment is to study fission product migration from failed TRISO particles in prototypic HTGR components such as structural graphite and compact matrix material. In this work, the potential for a Gamma Emission Computed Tomography (GECT) technique to non-destructively examine the fission product distribution in AGR-3/4 components and other irradiation experiments is explored. Specifically, the feasibility of using the Idaho National Laboratory (INL) Hot Fuels Examination Facility (HFEF) Precision Gamma Scanner (PGS) system for this GECT application is considered. To test the feasibility, the response of the PGS system to idealized fission product distributions has been simulated using Monte Carlo radiation transport simulations. Previous work that applied similar techniques during the AGR-1 experiment will also be discussed as well as planned uses for the GECT technique during the post irradiation examination of the AGR-2 experiment. The GECT technique has also been applied to other irradiated nuclear fuel systems that were currently available in the HFEF hot cell including oxide fuel pins, metallic fuel pins, and monolithic plate fuel.« less

Platinum supported on titanium–ruthenium oxide is a remarkably stable electrocatayst for hydrogen fuel cell vehicles

PubMed Central

Parrondo, Javier; Han, Taehee; Niangar, Ellazar; Wang, Chunmei; Dale, Nilesh; Adjemian, Kev; Ramani, Vijay

2014-01-01

We report a unique and highly stable electrocatalyst—platinum (Pt) supported on titanium–ruthenium oxide (TRO)—for hydrogen fuel cell vehicles. The Pt/TRO electrocatalyst was exposed to stringent accelerated test protocols designed to induce degradation and failure mechanisms identical to those seen during extended normal operation of a fuel cell automobile—namely, support corrosion during vehicle startup and shutdown, and platinum dissolution during vehicle acceleration and deceleration. These experiments were performed both ex situ (on supports and catalysts deposited onto a glassy carbon rotating disk electrode) and in situ (in a membrane electrode assembly). The Pt/TRO was compared against a state-of-the-art benchmark catalyst—Pt supported on high surface-area carbon (Pt/HSAC). In ex situ tests, Pt/TRO lost only 18% of its initial oxygen reduction reaction mass activity and 3% of its oxygen reduction reaction-specific activity, whereas the corresponding losses for Pt/HSAC were 52% and 22%. In in situ-accelerated degradation tests performed on membrane electrode assemblies, the loss in cell voltage at 1 A · cm−2 at 100% RH was a negligible 15 mV for Pt/TRO, whereas the loss was too high to permit operation at 1 A · cm−2 for Pt/HSAC. We clearly show that electrocatalyst support corrosion induced during fuel cell startup and shutdown is a far more potent failure mode than platinum dissolution during fuel cell operation. Hence, we posit that the need for a highly stable support (such as TRO) is paramount. Finally, we demonstrate that the corrosion of carbon present in the gas diffusion layer of the fuel cell is only of minor concern. PMID:24367118

Platinum supported on titanium-ruthenium oxide is a remarkably stable electrocatayst for hydrogen fuel cell vehicles.

PubMed

Parrondo, Javier; Han, Taehee; Niangar, Ellazar; Wang, Chunmei; Dale, Nilesh; Adjemian, Kev; Ramani, Vijay

2014-01-07

We report a unique and highly stable electrocatalyst-platinum (Pt) supported on titanium-ruthenium oxide (TRO)-for hydrogen fuel cell vehicles. The Pt/TRO electrocatalyst was exposed to stringent accelerated test protocols designed to induce degradation and failure mechanisms identical to those seen during extended normal operation of a fuel cell automobile-namely, support corrosion during vehicle startup and shutdown, and platinum dissolution during vehicle acceleration and deceleration. These experiments were performed both ex situ (on supports and catalysts deposited onto a glassy carbon rotating disk electrode) and in situ (in a membrane electrode assembly). The Pt/TRO was compared against a state-of-the-art benchmark catalyst-Pt supported on high surface-area carbon (Pt/HSAC). In ex situ tests, Pt/TRO lost only 18% of its initial oxygen reduction reaction mass activity and 3% of its oxygen reduction reaction-specific activity, whereas the corresponding losses for Pt/HSAC were 52% and 22%. In in situ-accelerated degradation tests performed on membrane electrode assemblies, the loss in cell voltage at 1 A · cm(-2) at 100% RH was a negligible 15 mV for Pt/TRO, whereas the loss was too high to permit operation at 1 A · cm(-2) for Pt/HSAC. We clearly show that electrocatalyst support corrosion induced during fuel cell startup and shutdown is a far more potent failure mode than platinum dissolution during fuel cell operation. Hence, we posit that the need for a highly stable support (such as TRO) is paramount. Finally, we demonstrate that the corrosion of carbon present in the gas diffusion layer of the fuel cell is only of minor concern.

Small stack performance of intermediate temperature-operating solid oxide fuel cells using stainless steel interconnects and anode-supported single cell

NASA Astrophysics Data System (ADS)

Bae, Joongmyeon; Lim, Sungkwang; Jee, Hyunjin; Kim, Jung Hyun; Yoo, Young-Sung; Lee, Taehee

We are developing 1 kW class solid oxide fuel cell (SOFC) system for residential power generation (RPG) application supported by Korean Government. Anode-supported single cells with thin electrolyte layer of YSZ (yttria-stabilized zirconia) or ScSZ (scandia-stabilized zirconia) for intermediate temperature operation (650-750 °C), respectively, were fabricated and small stacks were built and evaluated. The LSCF/ScSZ/Ni-YSZ single cell showed performance of 543 mW cm -2 at 650 °C and 1680 mW cm -2 at 750 °C. The voltage of 15-cell stack based on 5 cm × 5 cm single cell (LSM/YSZ/Ni-YSZ) at 150 mW was 12.5 V in hydrogen as fuel of 120 sccm per cell at 750 °C and decreased to about 10.9 V at 500 h operation time. A 5-cell stack based on the LSCF/YSZ/FL/Ni-YSZ showed the maximum power density of 30 W, 25 W and 20 W at 750 °C, 700 °C and 650 °C, respectively. LSCF/ScSZ/Ni-YSZ-based stack showed better performance than LSCF/YSZ/Ni-YSZ stack from the experiment temperature range. I- V characteristics by using hydrogen gas and reformate gas of methane as fuel were investigated at 750 °C in LSCF/ScSZ/FL/Ni-YSZ-based 5-cell stack.

Controlled Hydrogen Fleet and Infrastructure Demonstration Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dr. Scott Staley

2010-03-31

This program was undertaken in response to the US Department of Energy Solicitation DE-PS30-03GO93010, resulting in this Cooperative Agreement with the Ford Motor Company and BP to demonstrate and evaluate hydrogen fuel cell vehicles and required fueling infrastructure. Ford initially placed 18 hydrogen fuel cell vehicles (FCV) in three geographic regions of the US (Sacramento, CA; Orlando, FL; and southeast Michigan). Subsequently, 8 advanced technology vehicles were developed and evaluated by the Ford engineering team in Michigan. BP is Ford's principal partner and co-applicant on this project and provided the hydrogen infrastructure to support the fuel cell vehicles. BP ultimatelymore » provided three new fueling stations. The Ford-BP program consists of two overlapping phases. The deliverables of this project, combined with those of other industry consortia, are to be used to provide critical input to hydrogen economy commercialization decisions by 2015. The program's goal is to support industry efforts of the US President's Hydrogen Fuel Initiative in developing a path to a hydrogen economy. This program was designed to seek complete systems solutions to address hydrogen infrastructure and vehicle development, and possible synergies between hydrogen fuel electricity generation and transportation applications. This project, in support of that national goal, was designed to gain real world experience with Hydrogen powered Fuel Cell Vehicles (H2FCV) 'on the road' used in everyday activities, and further, to begin the development of the required supporting H2 infrastructure. Implementation of a new hydrogen vehicle technology is, as expected, complex because of the need for parallel introduction of a viable, available fuel delivery system and sufficient numbers of vehicles to buy fuel to justify expansion of the fueling infrastructure. Viability of the fuel structure means widespread, affordable hydrogen which can return a reasonable profit to the fuel provider, while viability of the vehicle requires an expected level of cost, comfort, safety and operation, especially driving range, that consumers require. This presents a classic 'chicken and egg' problem, which Ford believes can be solved with thoughtful implementation plans. The eighteen Ford Focus FCV vehicles that were operated for this demonstration project provided the desired real world experience. Some things worked better than expected. Most notable was the robustness and life of the fuel cell. This is thought to be the result of the full hybrid configuration of the drive system where the battery helps to overcome the performance reduction associated with time related fuel cell degradation. In addition, customer satisfaction surveys indicated that people like the cars and the concept and operated them with little hesitation. Although the demonstrated range of the cars was near 200 miles, operators felt constrained because of the lack of a number of conveniently located fueling stations. Overcoming this major concern requires overcoming a key roadblock, fuel storage, in a manner that permits sufficient quantity of fuel without sacrificing passenger or cargo capability. Fueling infrastructure, on the other hand, has been problematic. Only three of a planned seven stations were opened. The difficulty in obtaining public approval and local government support for hydrogen fuel, based largely on the fear of hydrogen that grew from past disasters and atomic weaponry, has inhibited progress and presents a major roadblock to implementation. In addition the cost of hydrogen production, in any of the methodologies used in this program, does not show a rapid reduction to commercially viable rates. On the positive side of this issue was the demonstrated safety of the fueling station, equipment and process. In the Ford program, there were no reported safety incidents.« less

Review of Fuel Cell Technologies for Military Land Vehicles

DTIC Science & Technology

2014-09-01

fuel cell technologies for APUs are Proton Exchange Membrane Fuel Cells ( PEMFC ), direct methanol fuel cells and Solid Oxide Fuel Cells (SOFC). The...6 4.2 Proton Exchange Membrane Fuel Cells ( PEMFC ...OEM Original Equipment Manufacturer PEM Proton Exchange Membrane PEMFC Proton Exchange Membrane Fuel Cell SOFC Solid Oxide Fuel Cell TRL Technical

Analysis of Deactivation Mechanism on a Multi-Component Sulfur-Tolerant Steam Reforming Catalyst

DTIC Science & Technology

2010-08-01

Alkaline Fuel Cells (AFC) .............................................................................. 4 1.1.2. Proton Exchange Membrane Fuel Cells ( PEMFC ...temperature fuel cells. Alkaline Fuel Cell (AFC), Proton Exchange Membrane Fuel Cell ( PEMFC ), DMFC and Phosphoric Acid Fuel Cell (PAFC) are low...1960s. 1.1.2. Proton Exchange Membrane Fuel Cells ( PEMFC ) Proton exchange membrane fuel cells are said to be the best type of fuel cells to replace

Evidence for Direct Electron Transfer by a Gram-Positive Bacterium Isolated from a Microbial Fuel Cell▿†

PubMed Central

Wrighton, K. C.; Thrash, J. C.; Melnyk, R. A.; Bigi, J. P.; Byrne-Bailey, K. G.; Remis, J. P.; Schichnes, D.; Auer, M.; Chang, C. J.; Coates, J. D.

2011-01-01

Despite their importance in iron redox cycles and bioenergy production, the underlying physiological, genetic, and biochemical mechanisms of extracellular electron transfer by Gram-positive bacteria remain insufficiently understood. In this work, we investigated respiration by Thermincola potens strain JR, a Gram-positive isolate obtained from the anode surface of a microbial fuel cell, using insoluble electron acceptors. We found no evidence that soluble redox-active components were secreted into the surrounding medium on the basis of physiological experiments and cyclic voltammetry measurements. Confocal microscopy revealed highly stratified biofilms in which cells contacting the electrode surface were disproportionately viable relative to the rest of the biofilm. Furthermore, there was no correlation between biofilm thickness and power production, suggesting that cells in contact with the electrode were primarily responsible for current generation. These data, along with cryo-electron microscopy experiments, support contact-dependent electron transfer by T. potens strain JR from the cell membrane across the 37-nm cell envelope to the cell surface. Furthermore, we present physiological and genomic evidence that c-type cytochromes play a role in charge transfer across the Gram-positive bacterial cell envelope during metal reduction. PMID:21908627

Fuel economy and life-cycle cost analysis of a fuel cell hybrid vehicle

NASA Astrophysics Data System (ADS)

Jeong, Kwi Seong; Oh, Byeong Soo

The most promising vehicle engine that can overcome the problem of present internal combustion is the hydrogen fuel cell. Fuel cells are devices that change chemical energy directly into electrical energy without combustion. Pure fuel cell vehicles and fuel cell hybrid vehicles (i.e. a combination of fuel cell and battery) as energy sources are studied. Considerations of efficiency, fuel economy, and the characteristics of power output in hybridization of fuel cell vehicle are necessary. In the case of Federal Urban Driving Schedule (FUDS) cycle simulation, hybridization is more efficient than a pure fuel cell vehicle. The reason is that it is possible to capture regenerative braking energy and to operate the fuel cell system within a more efficient range by using battery. Life-cycle cost is largely affected by the fuel cell size, fuel cell cost, and hydrogen cost. When the cost of fuel cell is high, hybridization is profitable, but when the cost of fuel cell is less than 400 US$/kW, a pure fuel cell vehicle is more profitable.

Conductive polymer layers to limit transfer of fuel reactants to catalysts of fuel cells to reduce reactant crossover

DOEpatents

Stanis, Ronald J.; Lambert, Timothy N.

2016-12-06

An apparatus of an aspect includes a fuel cell catalyst layer. The fuel cell catalyst layer is operable to catalyze a reaction involving a fuel reactant. A fuel cell gas diffusion layer is coupled with the fuel cell catalyst layer. The fuel cell gas diffusion layer includes a porous electrically conductive material. The porous electrically conductive material is operable to allow the fuel reactant to transfer through the fuel cell gas diffusion layer to reach the fuel cell catalyst layer. The porous electrically conductive material is also operable to conduct electrons associated with the reaction through the fuel cell gas diffusion layer. An electrically conductive polymer material is coupled with the fuel cell gas diffusion layer. The electrically conductive polymer material is operable to limit transfer of the fuel reactant to the fuel cell catalyst layer.

A Novel Range-Extended Strategy for Fuel Cell/Battery Electric Vehicles.

PubMed

Hwang, Jenn-Jiang; Hu, Jia-Sheng; Lin, Chih-Hong

2015-01-01

The range-extended electric vehicle is proposed to improve the range anxiety drivers have of electric vehicles. Conventionally, a gasoline/diesel generator increases the range of an electric vehicle. Due to the zero-CO2 emission stipulations, utilizing fuel cells as generators raises concerns in society. This paper presents a novel charging strategy for fuel cell/battery electric vehicles. In comparison to the conventional switch control, a fuzzy control approach is employed to enhance the battery's state of charge (SOC). This approach improves the quick loss problem of the system's SOC and thus can achieve an extended driving range. Smooth steering experience and range extension are the main indexes for development of fuzzy rules, which are mainly based on the energy management in the urban driving model. Evaluation of the entire control system is performed by simulation, which demonstrates its effectiveness and feasibility.

A Novel Range-Extended Strategy for Fuel Cell/Battery Electric Vehicles

PubMed Central

Hwang, Jenn-Jiang; Lin, Chih-Hong

2015-01-01

The range-extended electric vehicle is proposed to improve the range anxiety drivers have of electric vehicles. Conventionally, a gasoline/diesel generator increases the range of an electric vehicle. Due to the zero-CO2 emission stipulations, utilizing fuel cells as generators raises concerns in society. This paper presents a novel charging strategy for fuel cell/battery electric vehicles. In comparison to the conventional switch control, a fuzzy control approach is employed to enhance the battery's state of charge (SOC). This approach improves the quick loss problem of the system's SOC and thus can achieve an extended driving range. Smooth steering experience and range extension are the main indexes for development of fuzzy rules, which are mainly based on the energy management in the urban driving model. Evaluation of the entire control system is performed by simulation, which demonstrates its effectiveness and feasibility. PMID:26236771

Validation of pore network simulations of ex-situ water distributions in a gas diffusion layer of proton exchange membrane fuel cells with X-ray tomographic images

NASA Astrophysics Data System (ADS)

Agaesse, Tristan; Lamibrac, Adrien; Büchi, Felix N.; Pauchet, Joel; Prat, Marc

2016-11-01

Understanding and modeling two-phase flows in the gas diffusion layer (GDL) of proton exchange membrane fuel cells are important in order to improve fuel cells performance. They are scientifically challenging because of the peculiarities of GDLs microstructures. In the present work, simulations on a pore network model are compared to X-ray tomographic images of water distributions during an ex-situ water invasion experiment. A method based on watershed segmentation was developed to extract a pore network from the 3D segmented image of the dry GDL. Pore network modeling and a full morphology model were then used to perform two-phase simulations and compared to the experimental data. The results show good agreement between experimental and simulated microscopic water distributions. Pore network extraction parameters were also benchmarked using the experimental data and results from full morphology simulations.

A Hybrid Approach to Tactical Vehicles

DTIC Science & Technology

2011-09-01

membrane fuel cell ( PEMFC ), molten carbonate fuel cell (MCFC), solid oxide fuel cell (SOFC), phosphoric acid fuel cell (PAFC), alkaline fuel cell (AFC...and the direct methanol fuel cell (DMFC) (Ehsani, Gao, & Emadi, 2010). Of the six major types of fuel cells; the PEMFC , SOFC, and AFC are... PEMFC (21st Century Truck Program, 2000). There are a number of advantages of using a fuel cell as the primary power source for a vehicle. All fuel

Solid oxide fuel cell generator with removable modular fuel cell stack configurations

DOEpatents

Gillett, J.E.; Dederer, J.T.; Zafred, P.R.; Collie, J.C.

1998-04-21

A high temperature solid oxide fuel cell generator produces electrical power from oxidation of hydrocarbon fuel gases such as natural gas, or conditioned fuel gases, such as carbon monoxide or hydrogen, with oxidant gases, such as air or oxygen. This electrochemical reaction occurs in a plurality of electrically connected solid oxide fuel cells bundled and arrayed in a unitary modular fuel cell stack disposed in a compartment in the generator container. The use of a unitary modular fuel cell stack in a generator is similar in concept to that of a removable battery. The fuel cell stack is provided in a pre-assembled self-supporting configuration where the fuel cells are mounted to a common structural base having surrounding side walls defining a chamber. Associated generator equipment may also be mounted to the fuel cell stack configuration to be integral therewith, such as a fuel and oxidant supply and distribution systems, fuel reformation systems, fuel cell support systems, combustion, exhaust and spent fuel recirculation systems, and the like. The pre-assembled self-supporting fuel cell stack arrangement allows for easier assembly, installation, maintenance, better structural support and longer life of the fuel cells contained in the fuel cell stack. 8 figs.

Solid oxide fuel cell generator with removable modular fuel cell stack configurations

DOEpatents

Gillett, James E.; Dederer, Jeffrey T.; Zafred, Paolo R.; Collie, Jeffrey C.

1998-01-01

A high temperature solid oxide fuel cell generator produces electrical power from oxidation of hydrocarbon fuel gases such as natural gas, or conditioned fuel gases, such as carbon monoxide or hydrogen, with oxidant gases, such as air or oxygen. This electrochemical reaction occurs in a plurality of electrically connected solid oxide fuel cells bundled and arrayed in a unitary modular fuel cell stack disposed in a compartment in the generator container. The use of a unitary modular fuel cell stack in a generator is similar in concept to that of a removable battery. The fuel cell stack is provided in a pre-assembled self-supporting configuration where the fuel cells are mounted to a common structural base having surrounding side walls defining a chamber. Associated generator equipment may also be mounted to the fuel cell stack configuration to be integral therewith, such as a fuel and oxidant supply and distribution systems, fuel reformation systems, fuel cell support systems, combustion, exhaust and spent fuel recirculation systems, and the like. The pre-assembled self-supporting fuel cell stack arrangement allows for easier assembly, installation, maintenance, better structural support and longer life of the fuel cells contained in the fuel cell stack.

Fuel Cell Development and Test Laboratory | Energy Systems Integration

Science.gov Websites

Facility | NREL Fuel Cell Development and Test Laboratory Fuel Cell Development and Test Laboratory The Energy System Integration Facility's Fuel Cell Development and Test Laboratory supports fuel a fuel cell test in the Fuel Cell Development and Test Laboratory. Capability Hubs The Fuel Cell

Hydrogen and Fuel Cell Basics | Hydrogen and Fuel Cells | NREL

Science.gov Websites

Hydrogen and Fuel Cell Basics Hydrogen and Fuel Cell Basics NREL researchers are working to unlock the potential of hydrogen as a fuel and to advance fuel cell technologies for automobiles, equipment basics of NREL's hydrogen and fuel cell research and development. Fuel cell electric vehicles (FCEVs

Fuel cell generator with fuel electrodes that control on-cell fuel reformation

DOEpatents

Ruka, Roswell J [Pittsburgh, PA; Basel, Richard A [Pittsburgh, PA; Zhang, Gong [Murrysville, PA

2011-10-25

A fuel cell for a fuel cell generator including a housing including a gas flow path for receiving a fuel from a fuel source and directing the fuel across the fuel cell. The fuel cell includes an elongate member including opposing first and second ends and defining an interior cathode portion and an exterior anode portion. The interior cathode portion includes an electrode in contact with an oxidant flow path. The exterior anode portion includes an electrode in contact with the fuel in the gas flow path. The anode portion includes a catalyst material for effecting fuel reformation along the fuel cell between the opposing ends. A fuel reformation control layer is applied over the catalyst material for reducing a rate of fuel reformation on the fuel cell. The control layer effects a variable reformation rate along the length of the fuel cell.

Fractal diffusion in high temperature polymer electrolyte fuel cell membranes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hopfenmuller, Bernhard; Zorn, Reiner; Holderer, Olaf

In this paper, the performance of fuel cells depends largely on the proton diffusion in the proton conducting membrane, the core of a fuel cell. High temperature polymer electrolyte fuel cells are based on a polymer membrane swollen with phosphoric acid as the electrolyte, where proton conduction takes place. We studied the proton diffusion in such membranes with neutron scattering techniques which are especially sensitive to the proton contribution. Time of flight spectroscopy and backscattering spectroscopy have been combined to cover a broad dynamic range. In order to selectively observe the diffusion of protons potentially contributing to the ion conductivity,more » two samples were prepared, where in one of the samples the phosphoric acid was used with hydrogen replaced by deuterium. The scattering data from the two samples were subtracted in a suitable way after measurement. Thereby subdiffusive behavior of the proton diffusion has been observed and interpreted in terms of a model of fractal diffusion. For this purpose, a scattering function for fractal diffusion has been developed. The fractal diffusion dimension d w and the Hausdorff dimension d f have been determined on the length scales covered in the neutron scattering experiments.« less

Nitrogen-doped graphdiyne as a metal-free catalyst for high-performance oxygen reduction reactions

NASA Astrophysics Data System (ADS)

Liu, Rongji; Liu, Huibiao; Li, Yuliang; Yi, Yuanping; Shang, Xinke; Zhang, Shuangshuang; Yu, Xuelian; Zhang, Suojiang; Cao, Hongbin; Zhang, Guangjin

2014-09-01

Fuel cells and metal-air batteries will only become widely available in everyday life when the expensive platinum-based electrocatalysts used for the oxygen reduction reactions are replaced by other efficient, low-cost and stable catalysts. We report here the use of nitrogen-doped graphdiyne as a metal-free electrode with a comparable electrocatalytic activity to commercial Pt/C catalysts for the oxygen reduction reaction in alkaline fuel cells. Nitrogen-doped graphdiyne has a better stability and increased tolerance to the cross-over effect than conventional Pt/C catalysts.Fuel cells and metal-air batteries will only become widely available in everyday life when the expensive platinum-based electrocatalysts used for the oxygen reduction reactions are replaced by other efficient, low-cost and stable catalysts. We report here the use of nitrogen-doped graphdiyne as a metal-free electrode with a comparable electrocatalytic activity to commercial Pt/C catalysts for the oxygen reduction reaction in alkaline fuel cells. Nitrogen-doped graphdiyne has a better stability and increased tolerance to the cross-over effect than conventional Pt/C catalysts. Electronic supplementary information (ESI) available: Detailed RDE and RRDE experiments, additional tables and figures. See DOI: 10.1039/c4nr03185g

Fractal diffusion in high temperature polymer electrolyte fuel cell membranes

DOE PAGES

Hopfenmuller, Bernhard; Zorn, Reiner; Holderer, Olaf; ...

2018-05-29

In this paper, the performance of fuel cells depends largely on the proton diffusion in the proton conducting membrane, the core of a fuel cell. High temperature polymer electrolyte fuel cells are based on a polymer membrane swollen with phosphoric acid as the electrolyte, where proton conduction takes place. We studied the proton diffusion in such membranes with neutron scattering techniques which are especially sensitive to the proton contribution. Time of flight spectroscopy and backscattering spectroscopy have been combined to cover a broad dynamic range. In order to selectively observe the diffusion of protons potentially contributing to the ion conductivity,more » two samples were prepared, where in one of the samples the phosphoric acid was used with hydrogen replaced by deuterium. The scattering data from the two samples were subtracted in a suitable way after measurement. Thereby subdiffusive behavior of the proton diffusion has been observed and interpreted in terms of a model of fractal diffusion. For this purpose, a scattering function for fractal diffusion has been developed. The fractal diffusion dimension d w and the Hausdorff dimension d f have been determined on the length scales covered in the neutron scattering experiments.« less

Fuel cell with internal flow control

DOEpatents

Haltiner, Jr., Karl J.; Venkiteswaran, Arun [Karnataka, IN

2012-06-12

A fuel cell stack is provided with a plurality of fuel cell cassettes where each fuel cell cassette has a fuel cell with an anode and cathode. The fuel cell stack includes an anode supply chimney for supplying fuel to the anode of each fuel cell cassette, an anode return chimney for removing anode exhaust from the anode of each fuel cell cassette, a cathode supply chimney for supplying oxidant to the cathode of each fuel cell cassette, and a cathode return chimney for removing cathode exhaust from the cathode of each fuel cell cassette. A first fuel cell cassette includes a flow control member disposed between the anode supply chimney and the anode return chimney or between the cathode supply chimney and the cathode return chimney such that the flow control member provides a flow restriction different from at least one other fuel cell cassettes.

Effect of System Contaminants on the Performance of a Proton Exchange Membrane Fuel Cell

DOE PAGES

Mehrabadi, Bahareh Alsadat Tavakoli; Dinh, Huyen N.; Bender, Guido; ...

2016-11-10

The performance loss and recovery of the fuel cell due to Balance of Plant (BOP) contaminants was identified via a combination of experimental data and a mathematical model. The experiments were designed to study the influence of organic contaminants (e.g. those from BOP materials) on the resistance of the catalyst, ionomer and membrane, and a mathematical model was developed that allowed us to separate these competing resistances from the data collected on an operating fuel cell. For this reason, based on the functional groups, four organic contaminants found in BOP materials, diethylene glycol monoethyl ether (DGMEE), diethylene glycol monoethyl ethermore » acetate (DGMEA), benzyl alcohol (BzOH) and 2,6-diaminotoluene (2,6-DAT) were infused separately to the cathode side of the fuel cell. The cell voltage and high frequency impedance resistance was measured as a function of time. The contaminant feed was then discontinued and voltage recovery was measured. It was determined that compounds with ion exchange properties like 2,6-DAT can cause voltage loss with non-reversible recovery, so this compound was studied in more detail. Finally, the degree of voltage loss increased with an increase in concentration, and/or infusion time, and increased with a decrease in catalyst loadings.« less

Limitations of Commercializing Fuel Cell Technologies

NASA Astrophysics Data System (ADS)

Nordin, Normayati

2010-06-01

Fuel cell is the technology that, nowadays, is deemed having a great potential to be used in supplying energy. Basically, fuel cells can be categorized particularly by the kind of employed electrolyte. Several fuel cells types which are currently identified having huge potential to be utilized, namely, Solid Oxide Fuel Cells (SOFC), Molten Carbonate Fuel Cells (MCFC), Alkaline Fuel Cells (AFC), Phosphoric Acid Fuel Cells (PAFC), Polymer Electron Membrane Fuel Cell (PEMFC), Direct Methanol Fuel Cells (DMFC) and Regenerative Fuel Cells (RFC). In general, each of these fuel cells types has their own characteristics and specifications which assign the capability and suitability of them to be utilized for any particular applications. Stationary power generations and transport applications are the two most significant applications currently aimed for the fuel cell market. It is generally accepted that there are lots of advantages if fuel cells can be excessively commercialized primarily in context of environmental concerns and energy security. Nevertheless, this is a demanding task to be accomplished, as there is some gap in fuel cells technology itself which needs a major enhancement. It can be concluded, from the previous study, cost, durability and performance are identified as the main limitations to be firstly overcome in enabling fuel cells technology become viable for the market.

Physicochemical and toxicological characteristics of particulate matter emitted from a non-road diesel engine: comparative evaluation of biodiesel-diesel and butanol-diesel blends.

PubMed

Zhang, Zhi-Hui; Balasubramanian, Rajasekhar

2014-01-15

Combustion experiments were conducted to evaluate the effects of using blends of ultralow sulfur diesel (ULSD) with biodiesel or n-butanol on physicochemical and toxicological characteristics of particulate emissions from a non-road diesel engine. The results indicated that compared to ULSD, both the blended fuels could effectively reduce the particulate mass and elemental carbon emissions, with butanol being more effective than biodiesel. The proportion of organic carbon and volatile organic compounds in particles increased for both blended fuels. However, biodiesel blended fuels showed lower total particle-phase polycyclic aromatic hydrocarbons (PAHs) emissions. The total number emissions of particles ≤560nm in diameter decreased gradually for the butanol blended fuels, but increased significantly for the biodiesel blended fuels. Both the blended fuels indicated lower soot ignition temperature and activation energy. All the particle extracts showed a decline in cell viability with the increased dose. However, the change in cell viability among test fuels is not statistically significant different with the exception of DB-4 (biodiesel-diesel blend containing 4% oxygen) used at 75% engine load. Copyright © 2013 Elsevier B.V. All rights reserved.

Internal reforming fuel cell assembly with simplified fuel feed

DOEpatents

Farooque, Mohammad; Novacco, Lawrence J.; Allen, Jeffrey P.

2001-01-01

A fuel cell assembly in which fuel cells adapted to internally reform fuel and fuel reformers for reforming fuel are arranged in a fuel cell stack. The fuel inlet ports of the fuel cells and the fuel inlet ports and reformed fuel outlet ports of the fuel reformers are arranged on one face of the fuel cell stack. A manifold sealing encloses this face of the stack and a reformer fuel delivery system is arranged entirely within the region between the manifold and the one face of the stack. The fuel reformer has a foil wrapping and a cover member forming with the foil wrapping an enclosed structure.

Thermodynamic Modeling and Dispatch of Distributed Energy Technologies including Fuel Cell -- Gas Turbine Hybrids

NASA Astrophysics Data System (ADS)

McLarty, Dustin Fogle

Distributed energy systems are a promising means by which to reduce both emissions and costs. Continuous generators must be responsive and highly efficiency to support building dynamics and intermittent on-site renewable power. Fuel cell -- gas turbine hybrids (FC/GT) are fuel-flexible generators capable of ultra-high efficiency, ultra-low emissions, and rapid power response. This work undertakes a detailed study of the electrochemistry, chemistry and mechanical dynamics governing the complex interaction between the individual systems in such a highly coupled hybrid arrangement. The mechanisms leading to the compressor stall/surge phenomena are studied for the increased risk posed to particular hybrid configurations. A novel fuel cell modeling method introduced captures various spatial resolutions, flow geometries, stack configurations and novel heat transfer pathways. Several promising hybrid configurations are analyzed throughout the work and a sensitivity analysis of seven design parameters is conducted. A simple estimating method is introduced for the combined system efficiency of a fuel cell and a turbine using component performance specifications. Existing solid oxide fuel cell technology is capable of hybrid efficiencies greater than 75% (LHV) operating on natural gas, and existing molten carbonate systems greater than 70% (LHV). A dynamic model is calibrated to accurately capture the physical coupling of a FC/GT demonstrator tested at UC Irvine. The 2900 hour experiment highlighted the sensitivity to small perturbations and a need for additional control development. Further sensitivity studies outlined the responsiveness and limits of different control approaches. The capability for substantial turn-down and load following through speed control and flow bypass with minimal impact on internal fuel cell thermal distribution is particularly promising to meet local demands or provide dispatchable support for renewable power. Advanced control and dispatch heuristics are discussed using a case study of the UCI central plant. Thermal energy storage introduces a time horizon into the dispatch optimization which requires novel solution strategies. Highly efficient and responsive generators are required to meet the increasingly dynamic loads of today's efficient buildings and intermittent local renewable wind and solar power. Fuel cell gas turbine hybrids will play an integral role in the complex and ever-changing solution to local electricity production.

Fuel cell end plate structure

DOEpatents

Guthrie, Robin J.; Katz, Murray; Schroll, Craig R.

1991-04-23

The end plates (16) of a fuel cell stack (12) are formed of a thin membrane. Pressure plates (20) exert compressive load through insulation layers (22, 26) to the membrane. Electrical contact between the end plates (16) and electrodes (50, 58) is maintained without deleterious making and breaking of electrical contacts during thermal transients. The thin end plate (16) under compressive load will not distort with a temperature difference across its thickness. Pressure plate (20) experiences a low thermal transient because it is insulated from the cell. The impact on the end plate of any slight deflection created in the pressure plate by temperature difference is minimized by the resilient pressure pad, in the form of insulation, therebetween.

Alternative Fuels Data Center: Fuel Cell Electric Vehicles

Science.gov Websites

Cell Electric Vehicles to someone by E-mail Share Alternative Fuels Data Center: Fuel Cell Electric Vehicles on Facebook Tweet about Alternative Fuels Data Center: Fuel Cell Electric Vehicles on Twitter Bookmark Alternative Fuels Data Center: Fuel Cell Electric Vehicles on Google Bookmark Alternative Fuels

1986 fuel cell seminar: Program and abstracts

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1986-10-01

Ninety nine brief papers are arranged under the following session headings: gas industry's 40 kw program, solid oxide fuel cell technology, phosphoric acid fuel cell technology, molten carbonate fuel cell technology, phosphoric acid fuel cell systems, power plants technology, fuel cell power plant designs, unconventional fuels, fuel cell application and economic assessments, and plans for commerical development. The papers are processed separately for the data base. (DLC)

Development of a new bench for puncturing of irradiated fuel rods in STAR hot laboratory

NASA Astrophysics Data System (ADS)

Petitprez, B.; Silvestre, P.; Valenza, P.; Boulore, A.; David, T.

2018-01-01

A new device for puncturing of irradiated fuel rods in commercial power plants has been designed by Fuel Research Department of CEA Cadarache in order to provide experimental data of high precision on fuel pins with various designs. It will replace the current set-up that has been used since 1998 in hot cell 2 of STAR facility with more than 200 rod puncturing experiments. Based on this consistent experimental feedback, the heavy-duty technique of rod perforation by clad punching has been preserved for the new bench. The method of double expansion of rod gases is also retained since it allows upgrading the confidence interval of volumetric results obtained from rod puncturing. Furthermore, many evolutions have been introduced in the new design in order to improve its reliability, to make the maintenance easier by remote handling and to reduce experimental uncertainties. Tightness components have been studied with Sealing Laboratory Maestral at Pierrelatte so as to make them able to work under mixed pressure conditions (from vacuum at 10-5 mbar up to pressure at 50 bars) and to lengthen their lifetime under permanent gamma irradiation in hot cell. Bench ergonomics has been optimized to make its operating by remote handling easier and to secure the critical phases of a puncturing experiment. A high pressure gas line equipped with high precision pressure sensors out of cell can be connected to the bench in cell for calibration purposes. Uncertainty analyses using Monte Carlo calculations have been performed in order to optimize capacity of the different volumes of the apparatus according to volumetric characteristics of the rod to be punctured. At last this device is composed of independent modules which allow puncturing fuel pins out of different geometries (PWR, BWR, VVER). After leak tests of the device and remote handling simulation in a mock-up cell, several punctures of calibrated specimens have been performed in 2016. The bench will be implemented soon in hot cell 2 of STAR facility for final qualification tests. PWR rod punctures are already planned for 2018.

More Than 1,000 Fuel Cell Units Deployed Through DOE ARRA Funding (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This NREL Hydrogen and Fuel Cell Technical Highlight describes how early market end users are operating 1,111 fuel cell units at 301 sites in 20 states with funding from the U.S. Department of Energy Fuel Cell Technologies Program and analysis by NREL. The American Recovery and Reinvestment Act (ARRA) funded the deployment of approximately 1,000 fuel cell systems in key early markets to accelerate the commercialization and deployment of fuel cells and fuel cell manufacturing, installation, maintenance, and support services. In support of the ARRA fuel cell deployment objectives, NREL analyzes and validates the technology in real-world applications, reports onmore » the technology status, and facilitates the development of fuel cell technologies, manufacturing, and operations in strategic markets-including material handling equipment, backup power, and stationary power-where fuel cells can compete with conventional technologies. NREL is validating hydrogen and fuel cell systems in real-world settings through data collection, analysis, and reporting. The fuel cell and infrastructure analysis provides an independent, third-party assessment that focuses on fuel cell system and hydrogen infrastructure performance, operation, maintenance, use, and safety. An objective of the ARRA fuel cell project-to deploy approximately 1,000 fuel cell systems in key early markets - has been met in two years. By the end of 2011, 504 material handling equipment (MHE) fuel cell units were operating at 8 facilities and 607 backup power fuel cell units were operating at 293 sites. MHE and backup power are two markets where fuel cells are capable of meeting the operating demands, and deployments can be leveraged to accelerate fuel cell commercialization.« less

Strong, Tough Glass Composites Developed for Solid Oxide Fuel Cell Seals

NASA Technical Reports Server (NTRS)

Bansal, Narottam P.; Choi, Sung R.

2005-01-01

A fuel cell is an electrochemical device that continuously converts the chemical energy of a fuel directly into electrical energy. It consists of an electrolyte, an anode, and a cathode. Various types of fuel cells are available, such as direct methanol fuel cells, alkaline fuel cells, proton-exchange-membrane fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, and solid oxide fuel cells (SOFCs). The salient features of an SOFC are all solid construction and high-temperature electrochemical-reaction-based operation, resulting in clean, efficient power generation from a variety of fuels. SOFCs are being developed for a broad range of applications, such as portable electronic devices, automobiles, power generation, and aeronautics.

Calculation evaluation of multiplying properties of LWR with thorium fuel

NASA Astrophysics Data System (ADS)

Shamanin, I. V.; Grachev, V. M.; Knyshev, V. V.; Bedenko, S. V.; Novikova, N. G.

2017-01-01

The results of multiplying properties design research of the unit cell and LWR fuel assembly with the high temperature gas-cooled thorium reactor fuel pellet are presented in the work. The calculation evaluation showed the possibility of using thorium in LWR effectively. In this case the amount of fissile isotope is 2.45 times smaller in comparison with the standard loading of LWR. The research and numerical experiments were carried out using the verified accounting code of the program MCU5, modern libraries of evaluated nuclear data and multigroup approximations.

Experimental results with fuel cell start-up and shut-down. Impact of type of carbon for cathode catalyst support

DOE PAGES

Lottin, Olivier; Dillet, Jerome; Maranzana, Gael; ...

2015-09-14

Separate testing protocols for fuel cell startups and shutdowns were developed to distinguish between their effects on reverse currents and CO 2 evolution. The internal currents and the local potentials were measured with different membrane-electrode assemblies (MEAs): we examined the influence of the type of carbon for cathode catalyst support as well as the mitigating effect of low anode Pt loading. In conclusion, significant differences were observed and the experiments also confirmed previous results that the evolved CO 2 accounts for less than 25% of the total exchanged charge.

Experimental results with fuel cell start-up and shut-down. Impact of type of carbon for cathode catalyst support

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lottin, Olivier; Dillet, Jerome; Maranzana, Gael

Separate testing protocols for fuel cell startups and shutdowns were developed to distinguish between their effects on reverse currents and CO 2 evolution. The internal currents and the local potentials were measured with different membrane-electrode assemblies (MEAs): we examined the influence of the type of carbon for cathode catalyst support as well as the mitigating effect of low anode Pt loading. In conclusion, significant differences were observed and the experiments also confirmed previous results that the evolved CO 2 accounts for less than 25% of the total exchanged charge.

Fuel cell power trains for road traffic

NASA Astrophysics Data System (ADS)

Höhlein, Bernd; Biedermann, Peter; Grube, Thomas; Menzer, Reinhard

Legal regulations, especially the low emission vehicle (LEV) laws in California, are the driving forces for more intensive technological developments with respect to a global automobile market. In the future, high efficient vehicles at very low emission levels will include low temperature fuel cell systems (e.g., polymer electrolyte fuel cell (PEFC)) as units of hydrogen-, methanol- or gasoline-based electric power trains. In the case of methanol or gasoline/diesel, hydrogen has to be produced on-board using heated steam or partial oxidation reformers as well as catalytic burners and gas cleaning units. Methanol could also be used for direct electricity generation inside the fuel cell (direct methanol fuel cell (DMFC)). The development potentials and the results achieved so far for these concepts differ extremely. Based on the experience gained so far, the goals for the next few years include cost and weight reductions as well as optimizations in terms of the energy management of power trains with PEFC systems. At the same time, questions of fuel specification, fuel cycle management, materials balances and environmental assessment will have to be discussed more intensively. On the basis of process engineering analyses for net electricity generation in PEFC-powered power trains as well as on assumptions for both electric power trains and vehicle configurations, overall balances have been carried out. They will lead not only to specific energy demand data and specific emission levels (CO 2, CO, VOC, NO x) for the vehicle but will also present data of its full fuel cycle (FFC) in comparison to those of FFCs including internal combustion engines (ICE) after the year 2005. Depending on the development status (today or in 2010) and the FFC benchmark results, the advantages of balances results of FFC with PEFC vehicles are small in terms of specific energy demand and CO 2 emissions, but very high with respect to local emission levels.

Control assembly for controlling a fuel cell system during shutdown and restart

DOEpatents

Venkataraman, Ramki; Berntsen, George; Carlson, Glenn L.; Farooque, Mohammad; Beachy, Dan; Peterhans, Stefan; Bischoff, Manfred

2010-06-15

A fuel cell system and method in which the fuel cell system receives and an input oxidant gas and an input fuel gas, and in which a fuel processing assembly is provided and is adapted to at least humidify the input fuel gas which is to be supplied to the anode of the fuel cell of the system whose cathode receives the oxidant input gas via an anode oxidizing assembly which is adapted to couple the output of the anode of the fuel cell to the inlet of the cathode of the fuel cell during normal operation, shutdown and restart of the fuel cell system, and in which a control assembly is further provided and is adapted to respond to shutdown of the fuel cell system during which input fuel gas and input oxidant gas cease to be received by the fuel cell system, the control assembly being further adapted to, when the fuel cell system is shut down: control the fuel cell system so as to enable a purging gas to be able to flow through the fuel processing assembly to remove humidified fuel gas from the processing assembly and to enable a purging gas to be able to flow through the anode of the fuel cell.

Fuel cells

NASA Astrophysics Data System (ADS)

Hooie, D. T.; Harrington, B. C., III; Mayfield, M. J.; Parsons, E. L.

1992-07-01

The primary objective of DOE's Fossil Energy Fuel Cell program is to fund the development of key fuel cell technologies in a manner that maximizes private sector participation and in a way that will give contractors the opportunity for a competitive posture, early market entry, and long-term market growth. This summary includes an overview of the Fuel Cell program, an elementary explanation of how fuel cells operate, and a synopsis of the three major fuel cell technologies sponsored by the DOE/Fossil Energy Phosphoric Acid Fuel Cell program, the Molten Carbonate Fuel Cell program, and the Solid Oxide Fuel Cell program.

Nanocrystalline cerium oxide materials for solid fuel cell systems

DOEpatents

Brinkman, Kyle S

2015-05-05

Disclosed are solid fuel cells, including solid oxide fuel cells and PEM fuel cells that include nanocrystalline cerium oxide materials as a component of the fuel cells. A solid oxide fuel cell can include nanocrystalline cerium oxide as a cathode component and microcrystalline cerium oxide as an electrolyte component, which can prevent mechanical failure and interdiffusion common in other fuel cells. A solid oxide fuel cell can also include nanocrystalline cerium oxide in the anode. A PEM fuel cell can include cerium oxide as a catalyst support in the cathode and optionally also in the anode.

A diesel fuel processor for fuel-cell-based auxiliary power unit applications

NASA Astrophysics Data System (ADS)

Samsun, Remzi Can; Krekel, Daniel; Pasel, Joachim; Prawitz, Matthias; Peters, Ralf; Stolten, Detlef

2017-07-01

Producing a hydrogen-rich gas from diesel fuel enables the efficient generation of electricity in a fuel-cell-based auxiliary power unit. In recent years, significant progress has been achieved in diesel reforming. One issue encountered is the stable operation of water-gas shift reactors with real reformates. A new fuel processor is developed using a commercial shift catalyst. The system is operated using optimized start-up and shut-down strategies. Experiments with diesel and kerosene fuels show slight performance drops in the shift reactor during continuous operation for 100 h. CO concentrations much lower than the target value are achieved during system operation in auxiliary power unit mode at partial loads of up to 60%. The regeneration leads to full recovery of the shift activity. Finally, a new operation strategy is developed whereby the gas hourly space velocity of the shift stages is re-designed. This strategy is validated using different diesel and kerosene fuels, showing a maximum CO concentration of 1.5% at the fuel processor outlet under extreme conditions, which can be tolerated by a high-temperature PEFC. The proposed operation strategy solves the issue of strong performance drop in the shift reactor and makes this technology available for reducing emissions in the transportation sector.

Fuel Cell and Hydrogen Technology Validation | Hydrogen and Fuel Cells |

Science.gov Websites

NREL Fuel Cell and Hydrogen Technology Validation Fuel Cell and Hydrogen Technology Validation The NREL technology validation team works on validating hydrogen fuel cell electric vehicles; hydrogen fueling infrastructure; hydrogen system components; and fuel cell use in early market applications such as

Alternative Fuels Data Center: Fuel Cell Electric Vehicle Emissions

Science.gov Websites

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Solar-induced direct biomass-to-electricity hybrid fuel cell using polyoxometalates as photocatalyst and charge carrier.

PubMed

Liu, Wei; Mu, Wei; Liu, Mengjie; Zhang, Xiaodan; Cai, Hongli; Deng, Yulin

2014-01-01

The current polymer-exchange membrane fuel cell technology cannot directly use biomass as fuel. Here we present a solar-induced hybrid fuel cell that is directly powered with natural polymeric biomasses, such as starch, cellulose, lignin, and even switchgrass and wood powders. The fuel cell uses polyoxometalates as the photocatalyst and charge carrier to generate electricity at low temperature. This solar-induced hybrid fuel cell combines some features of solar cells, fuel cells and redox flow batteries. The power density of the solar-induced hybrid fuel cell powered by cellulose reaches 0.72 mW cm(-2), which is almost 100 times higher than cellulose-based microbial fuel cells and is close to that of the best microbial fuel cells reported in literature. Unlike most cell technologies that are sensitive to impurities, the cell reported in this study is inert to most organic and inorganic contaminants present in the fuels.

Solar-induced direct biomass-to-electricity hybrid fuel cell using polyoxometalates as photocatalyst and charge carrier

NASA Astrophysics Data System (ADS)

Liu, Wei; Mu, Wei; Liu, Mengjie; Zhang, Xiaodan; Cai, Hongli; Deng, Yulin

2014-02-01

The current polymer-exchange membrane fuel cell technology cannot directly use biomass as fuel. Here we present a solar-induced hybrid fuel cell that is directly powered with natural polymeric biomasses, such as starch, cellulose, lignin, and even switchgrass and wood powders. The fuel cell uses polyoxometalates as the photocatalyst and charge carrier to generate electricity at low temperature. This solar-induced hybrid fuel cell combines some features of solar cells, fuel cells and redox flow batteries. The power density of the solar-induced hybrid fuel cell powered by cellulose reaches 0.72 mW cm-2, which is almost 100 times higher than cellulose-based microbial fuel cells and is close to that of the best microbial fuel cells reported in literature. Unlike most cell technologies that are sensitive to impurities, the cell reported in this study is inert to most organic and inorganic contaminants present in the fuels.

Indirect-fired gas turbine dual fuel cell power cycle

DOEpatents

Micheli, Paul L.; Williams, Mark C.; Sudhoff, Frederick A.

1996-01-01

A fuel cell and gas turbine combined cycle system which includes dual fuel cell cycles combined with a gas turbine cycle wherein a solid oxide fuel cell cycle operated at a pressure of between 6 to 15 atms tops the turbine cycle and is used to produce CO.sub.2 for a molten carbonate fuel cell cycle which bottoms the turbine and is operated at essentially atmospheric pressure. A high pressure combustor is used to combust the excess fuel from the topping fuel cell cycle to further heat the pressurized gas driving the turbine. A low pressure combustor is used to combust the excess fuel from the bottoming fuel cell to reheat the gas stream passing out of the turbine which is used to preheat the pressurized air stream entering the topping fuel cell before passing into the bottoming fuel cell cathode. The CO.sub.2 generated in the solid oxide fuel cell cycle cascades through the system to the molten carbonate fuel cell cycle cathode.

The Development of a Cell-Assembly for the Treatment of Irradiated Fuels on a Semi-Industrial Scale; ETUDE CONCERNANT LA REALISATION D'UN ENSEMBLE DE CELLULES DESTINEES A DES TRAITEMENTS DE COMBUSTIBLES IRRADIES A L'ECHELLE SEMI-INDUSTRIELLE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Faugeras, P.; Couture, J.; Lefort, G.

1961-01-01

The main studies and experiments involved in the development of a cell- assembly for the treatment of irradiated fuels on a semi-industrial scale are described. It must be possible to modify or transform each of these cells without interrupting the rest of the pilot. A full-scale prototype cell ( 3 x 4 x 6 m) was built with an alpha k-protection independent of the gamma - protection. It features all the main characteristics: tightness to gamma losses, dense glass lighting, and ventilation. This cell has made possible trials on transfer, remote-controls and teledismantling, as well as the development of newmore » methods of rapidly connecting hydraulic circuits. The final form is given of the cells selected for the pilot. (auth)« less

Contribution of direct electron transfer mechanisms to overall electron transfer in microbial fuel cells utilising Shewanella oneidensis as biocatalyst.

PubMed

Fapetu, Segun; Keshavarz, Taj; Clements, Mark; Kyazze, Godfrey

2016-09-01

To investigate the contribution of direct electron transfer mechanisms to electricity production in microbial fuel cells by physically retaining Shewanella oneidensis cells close to or away from the anode electrode. A maximum power output of 114 ± 6 mWm(-2) was obtained when cells were retained close to the anode using a dialysis membrane. This was 3.5 times more than when the cells were separated away from the anode. Without the membrane the maximum power output was 129 ± 6 mWm(-2). The direct mechanisms of electron transfer contributed significantly to overall electron transfer from S. oneidensis to electrodes, a result that was corroborated by another experiment where S. oneidensis cells were entrapped in alginate gels. S. oneidensis transfers electrons primarily by direct electron transfer as opposed to mediated electron transfer.

2009 Fuel Cell Market Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vincent, Bill; Gangi, Jennifer; Curtin, Sandra

Fuel cells are electrochemical devices that combine hydrogen and oxygen to produce electricity, water, and heat. Unlike batteries, fuel cells continuously generate electricity, as long as a source of fuel is supplied. Moreover, fuel cells do not burn fuel, making the process quiet, pollution-free and two to three times more efficient than combustion. Fuel cell systems can be a truly zero-emission source of electricity, if the hydrogen is produced from non-polluting sources. Global concerns about climate change, energy security, and air pollution are driving demand for fuel cell technology. More than 630 companies and laboratories in the United States aremore » investing $1 billion a year in fuel cells or fuel cell component technologies. This report provides an overview of trends in the fuel cell industry and markets, including product shipments, market development, and corporate performance. It also provides snapshots of select fuel cell companies, including general.« less

2009 Fuel Cell Market Report, November 2010

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

Fuel cells are electrochemical devices that combine hydrogen and oxygen to produce electricity, water, and heat. Unlike batteries, fuel cells continuously generate electricity, as long as a source of fuel is supplied. Moreover, fuel cells do not burn fuel, making the process quiet, pollution-free and two to three times more efficient than combustion. Fuel cell systems can be a truly zero-emission source of electricity, if the hydrogen is produced from non-polluting sources. Global concerns about climate change, energy security, and air pollution are driving demand for fuel cell technology. More than 630 companies and laboratories in the United States aremore » investing $1 billion a year in fuel cells or fuel cell component technologies. This report provides an overview of trends in the fuel cell industry and markets, including product shipments, market development, and corporate performance. It also provides snapshots of select fuel cell companies, including general.« less

The enhancement of ammonium removal from ethanolamine wastewater using air-cathode microbial fuel cells coupled to ferric reduction.

PubMed

Shin, Ja-Won; Seo, Seok-Ju; Maitlo, Hubdar Ali; Park, Joo-Yang

2015-08-01

A microbial fuel cell (MFC) with biological Fe(III) reduction was implemented for simultaneous ethanolamine (ETA) degradation and electrical energy generation. In the feasibility experiment using acetate as a substrate in a single-chamber MFC with goethite and ammonium at a ratio of 3.0(mol/mol), up to 96.1% of the ammonium was removed through the novel process related to Fe(III). In addition, the highest voltage output (0.53V) and maximum power density (0.49Wm(-2)) were obtained. However, the ammonium removal and electrical performance decreased as acetate was replaced with ETA. In the long-term experiment, the electrical performance markedly decreased where the voltage loss increased due to Fe deposition on the membranes. Copyright © 2015 Elsevier Ltd. All rights reserved.

National Fuel Cell Technology Evaluation Center | Hydrogen and Fuel Cells |

Science.gov Websites

NREL National Fuel Cell Technology Evaluation Center National Fuel Cell Technology Evaluation Center The National Fuel Cell Technology Evaluation Center (NFCTEC) at NREL's Energy Systems Integration Cell Technology Evaluation Center to process and analyze data for a variety of hydrogen and fuel cell

Status of commercial fuel cell powerplant system development

NASA Technical Reports Server (NTRS)

Warshay, Marvin

1987-01-01

The primary focus is on the development of commercial Phosphoric Acid Fuel Cell (PAFC) powerplant systems because the PAFC, which has undergone extensive development, is currently the closest fuel cell system to commercialization. Shorter discussions are included on the high temperature fuel cell systems which are not as mature in their development, such as the Molten Carbonate Fuel Cell (MCFC) and the Solid Oxide Fuel Cell (SOFC). The alkaline and the Solid Polymer Electrolyte (SPE) fuel cell systems, are also included, but their discussions are limited to their prospects for commercial development. Currently, although the alkaline fuel cell continues to be used for important space applications there are no commercial development programs of significant size in the USA and only small efforts outside. The market place for fuel cells and the status of fuel cell programs in the USA receive extensive treatment. The fuel cell efforts outside the USA, especially the large Japanese programs, are also discussed.

Fuel cell tubes and method of making same

DOEpatents

Borglum, Brian P.

1999-11-30

A method of manufacturing porous ceramic tubes for fuel cells with improved properties and higher manufacturing yield is disclosed. The method involves extruding a closed end fuel cell tube, such as an air electrode of a solid oxide fuel cell, in which the closed end also functions as the sintering support. The resultant fuel cell tube has a superior porosity distribution which allows improved diffusion of oxygen at the closed end of the tube during operation of the fuel cell. Because this region has the highest current density, performance enhancement and improved reliability of the fuel cell tube result. Furthermore, the higher manufacturing yield associated with the present method decreases the overall fuel cell cost. A method of manufacturing porous ceramic tubes for fuel cells with improved properties and higher manufacturing yield is disclosed. The method involves extruding a closed end fuel cell tube, such as an air electrode of a solid oxide fuel cell, in which the closed end also functions as the sintering support. The resultant fuel cell tube has a superior porosity distribution which allows improved diffusion of oxygen at the closed end of the tube during operation of the fuel cell. Because this region has the highest current density, performance enhancement and improved reliability of the fuel cell tube result. Furthermore, the higher manufacturing yield associated with the present method decreases the overall fuel cell cost.

Structural analysis of PrBaMn2O5+δ under SOFC anode conditions by in-situ neutron powder diffraction

NASA Astrophysics Data System (ADS)

Tomkiewicz, Alex C.; Tamimi, Mazin A.; Huq, Ashfia; McIntosh, Steven

2016-10-01

The crystal structure and oxygen stoichiometry of the proposed double perovskite solid oxide fuel cell (SOFC) anode material PrBaMn2O5+δ were determined under SOFC anode conditions via in-situ neutron diffraction. Measurements were performed in reducing atmospheres between 692 K and 984 K. The structure was fit to a tetragonal (space group P4/mmm) layered double perovskite structure with alternating Pr and Ba A-site cation layers. Under all conditions examined, the oxygen sites in the Ba and Mn layers were fully occupied, while the sites in the Pr layer were close to completely vacant. The results of the neutron diffraction experiments are compared to previous thermogravimetric analysis experiments to verify the accuracy of both experiments. PrBaMn2O5+δ was shown to be stable over a wide range of reducing atmospheres similar to anode operating conditions in solid oxide fuel cells without significant structural changes.

Fuel Cell and Hydrogen Technologies Program | Hydrogen and Fuel Cells |

Science.gov Websites

NREL Fuel Cell and Hydrogen Technologies Program Fuel Cell and Hydrogen Technologies Program Through its Fuel Cell and Hydrogen Technologies Program, NREL researches, develops, analyzes, and validates fuel cell and hydrogen production, delivery, and storage technologies for transportation

Rejuvenation of automotive fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Yu Seung; Langlois, David A.

A process for rejuvenating fuel cells has been demonstrated to improve the performance of polymer exchange membrane fuel cells with platinum/ionomer electrodes. The process involves dehydrating a fuel cell and exposing at least the cathode of the fuel cell to dry gas (nitrogen, for example) at a temperature higher than the operating temperature of the fuel cell. The process may be used to prolong the operating lifetime of an automotive fuel cell.

Development of PEM fuel cell technology at international fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wheeler, D.J.

1996-04-01

The PEM technology has not developed to the level of phosphoric acid fuel cells. Several factors have held the technology development back such as high membrane cost, sensitivity of PEM fuel cells to low level of carbon monoxide impurities, the requirement to maintain full humidification of the cell, and the need to pressurize the fuel cell in order to achieve the performance targets. International Fuel Cells has identified a hydrogen fueled PEM fuel cell concept that leverages recent research advances to overcome major economic and technical obstacles.

Open end protection for solid oxide fuel cells

DOEpatents

Zafred, Paolo R.; Dederer, Jeffrey T.; Tomlins, Gregory W.; Toms, James M.; Folser, George R.; Schmidt, Douglas S.; Singh, Prabhakar; Hager, Charles A.

2001-01-01

A solid oxide fuel cell (40) having a closed end (44) and an open end (42) operates in a fuel cell generator (10) where the fuel cell open end (42) of each fuel cell contains a sleeve (60, 64) fitted over the open end (42), where the sleeve (60, 64) extends beyond the open end (42) of the fuel cell (40) to prevent degradation of the interior air electrode of the fuel cell by fuel gas during operation of the generator (10).

World wide IFC phosphoric acid fuel cell implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

King, J.M. Jr

1996-04-01

International Fuel Cells, a subsidary of United technologies Corporation, is engaged in research and development of all types of fuel cell technologies and currently manufactures alkaline fuel cell power plants for the U.S. manned space flight program and natural gas fueled stationary power plants using phosphoric acid fuel cells. This paper describes the phosphoric acid fuel cell power plants.

Investigation of polymer electrolyte membrane fuel cell internal behaviour during long term operation and its use in prognostics

NASA Astrophysics Data System (ADS)

Mao, Lei; Jackson, Lisa; Jackson, Tom

2017-09-01

This paper investigates the polymer electrolyte membrane (PEM) fuel cell internal behaviour variation at different operating condition, with characterization test data taken at predefined inspection times, and uses the determined internal behaviour evolution to predict the future PEM fuel cell performance. For this purpose, a PEM fuel cell behaviour model is used, which can be related to various fuel cell losses. By matching the model to the collected polarization curves from the PEM fuel cell system, the variation of fuel cell internal behaviour can be obtained through the determined model parameters. From the results, the source of PEM fuel cell degradation during its lifetime at different conditions can be better understood. Moreover, with determined fuel cell internal behaviour, the future fuel cell performance can be obtained by predicting the future model parameters. By comparing with prognostic results using adaptive neuro fuzzy inference system (ANFIS), the proposed prognostic analysis can provide better predictions for PEM fuel cell performance at dynamic condition, and with the understanding of variation in PEM fuel cell internal behaviour, mitigation strategies can be designed to extend the fuel cell performance.

Carbonate fuel cell system with thermally integrated gasification

DOEpatents

Steinfeld, G.; Meyers, S.J.; Lee, A.

1996-09-10

A fuel cell system is described which employs a gasifier for generating fuel gas for the fuel cell of the fuel cell system and in which heat for the gasifier is derived from the anode exhaust gas of the fuel cell. 2 figs.

SPE (tm) regenerative hydrogen/oxygen fuel cells for extraterrestrial surface and microgravity applications

NASA Technical Reports Server (NTRS)

Mcelroy, J. F.

1990-01-01

Viewgraphs on SPE regenerative hydrogen/oxygen fuel cells for extraterrestrial surface and microgravity applications are presented. Topics covered include: hydrogen-oxygen regenerative fuel cell energy storage system; electrochemical cell reactions; SPE cell voltage stability; passive water removal SPE fuel cell; fuel cell performance; SPE water electrolyzers; hydrophobic oxygen phase separator; hydrophilic/electrochemical hydrogen phase separator; and unitized regenerative fuel cell.

Preliminary Design of an Autonomous Underwater Vehicle Using Multi-Objective Optimization

DTIC Science & Technology

2014-03-01

fuel cell PC propulsive coefficient PEMFC proton exchange membrane fuel cell PHP propulsive horsepower PO Pareto optimal PSO particle swarm...membrane fuel cell ( PEMFC ), molten carbonate fuel cell (MCFC), solid oxide fuel cell (SOFC) and direct and indirect methanol fuel cell (DMFC). Figure...of fuel cells in depth, I will note that PEMFCs are smaller and have a lower operating temperature compared to the other types. Those are the main

Solid oxide fuel cell generator

DOEpatents

Di Croce, A. Michael; Draper, Robert

1993-11-02

A solid oxide fuel cell generator has a plenum containing at least two rows of spaced apart, annular, axially elongated fuel cells. An electrical conductor extending between adjacent rows of fuel cells connects the fuel cells of one row in parallel with each other and in series with the fuel cells of the adjacent row.

Fuel Cell Vehicle Basics | NREL

Science.gov Websites

Fuel Cell Vehicle Basics Fuel Cell Vehicle Basics Researchers are developing fuel cells that can be silver four-door sedan being driven on a roadway and containing the words "hydrogen fuel cell electric" across the front and rear doors. This prototype hydrogen fuel cell electric vehicle was

Solid oxide fuel cell generator

DOEpatents

Di Croce, A.M.; Draper, R.

1993-11-02

A solid oxide fuel cell generator has a plenum containing at least two rows of spaced apart, annular, axially elongated fuel cells. An electrical conductor extending between adjacent rows of fuel cells connects the fuel cells of one row in parallel with each other and in series with the fuel cells of the adjacent row. 5 figures.

The Advantages of Non-Flow-Through Fuel Cell Power Systems for Aerospace Applications

NASA Technical Reports Server (NTRS)

Hoberecht, Mark; Burke, Kenneth; Jakupca, Ian

2011-01-01

NASA has been developing proton-exchange-membrane (PEM) fuel cell power systems for the past decade, as an upgraded technology to the alkaline fuel cells which presently provide power for the Shuttle Orbiter. All fuel cell power systems consist of one or more fuel cell stacks in combination with appropriate balance-of-plant hardware. Traditional PEM fuel cells are characterized as flow-through, in which recirculating reactant streams remove product water from the fuel cell stack. NASA recently embarked on the development of non-flow-through fuel cell systems, in which reactants are dead-ended into the fuel cell stack and product water is removed by internal wicks. This simplifies the fuel cell power system by eliminating the need for pumps to provide reactant circulation, and mechanical water separators to remove the product water from the recirculating reactant streams. By eliminating these mechanical components, the resulting fuel cell power system has lower mass, volume, and parasitic power requirements, along with higher reliability and longer life. These improved non-flow-through fuel cell power systems therefore offer significant advantages for many aerospace applications.

Reforming options for hydrogen production from fossil fuels for PEM fuel cells

NASA Astrophysics Data System (ADS)

Ersoz, Atilla; Olgun, Hayati; Ozdogan, Sibel

PEM fuel cell systems are considered as a sustainable option for the future transport sector in the future. There is great interest in converting current hydrocarbon based transportation fuels into hydrogen rich gases acceptable by PEM fuel cells on-board of vehicles. In this paper, we compare the results of our simulation studies for 100 kW PEM fuel cell systems utilizing three different major reforming technologies, namely steam reforming (SREF), partial oxidation (POX) and autothermal reforming (ATR). Natural gas, gasoline and diesel are the selected hydrocarbon fuels. It is desired to investigate the effect of the selected fuel reforming options on the overall fuel cell system efficiency, which depends on the fuel processing, PEM fuel cell and auxiliary system efficiencies. The Aspen-HYSYS 3.1 code has been used for simulation purposes. Process parameters of fuel preparation steps have been determined considering the limitations set by the catalysts and hydrocarbons involved. Results indicate that fuel properties, fuel processing system and its operation parameters, and PEM fuel cell characteristics all affect the overall system efficiencies. Steam reforming appears as the most efficient fuel preparation option for all investigated fuels. Natural gas with steam reforming shows the highest fuel cell system efficiency. Good heat integration within the fuel cell system is absolutely necessary to achieve acceptable overall system efficiencies.

2008 Fuel Cell Technologies Market Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

DOE

Fuel cells are electrochemical devices that combine hydrogen and oxygen to produce electricity, water, and heat. Unlike batteries, fuel cells continuously generate electricity, as long as a source of fuel is supplied. Moreover, fuel cells do not burn fuel, making the process quiet, pollution-free and two to three times more efficient than combustion. Fuel cell systems can be a truly zero-emission source of electricity, if the hydrogen is produced from non-polluting sources. Global concerns about climate change, energy security, and air pollution are driving demand for fuel cell technology. More than 630 companies and laboratories in the United States aremore » investing $1 billion a year in fuel cells or fuel cell component technologies. This report provides an overview of trends in the fuel cell industry and markets, including product shipments, market development, and corporate performance. It also provides snapshots of select fuel cell companies, including general business strategy and market focus, as well as, financial information for select publicly-traded companies.« less

Pt nanoparticle-reduced graphene oxide nanohybrid for proton exchange membrane fuel cells.

PubMed

Park, Dae-Hwan; Jeon, Yukwon; Ok, Jinhee; Park, Jooil; Yoon, Seong-Ho; Choy, Jin-Ho; Shul, Yong-Gun

2012-07-01

A platinum nanoparticle-reduced graphene oxide (Pt-RGO) nanohybrid for proton exchange membrane fuel cell (PEMFC) application was successfully prepared. The Pt nanoparticles (Pt NPs) were deposited onto chemically converted graphene nanosheets via ethylene glycol (EG) reduction. According to the powder X-ray diffraction (XRD) pattern and transmission electron microscopy (TEM) analysis, the face-centered cubic Pt NPs (3-5 nm in diameter) were homogeneously dispersed on the RGO nanosheets. The electrochemically active surface area and PEMFC power density of the Pt-RGO nanohybrid were determined to be 33.26 m2/g and 480 mW/cm2 (maximum values), respectively, at 75 degrees C and at a relative humidity (RH) of 100% in a single-cell test experiment.

Project Themis Supercritical Cold Flow Facility, Experiment Design and Modeling for the Study of Fluid Mixing

DTIC Science & Technology

2012-06-01

AFRL facility was well suited for the Themis cold flow experiment. A test cell was selected that contained an insulated cryogenic oxygen tank that...could be used for the LN2 supply. Adjacent to the test cell is a cryogenic storage bunker that contained a helium supply tank with existing high...venturi to the fuel bunker tank was very low (less than 25 psi) while the helium pressure drop from the cryogenic storage bunker was almost 2000 psi

Onsite 40-kilowatt fuel cell power plant manufacturing and field test program

NASA Technical Reports Server (NTRS)

1985-01-01

A joint Gas Research Institute and U.S. Department of Energy Program was initiated in 1982 to evaluate the use of fuel cell power systems for on-site energy service. Forty-six 40 kW fuel cell power plants were manufactured at the United Technologies Corporation facility in South Windsor, Connecticut, and are being delivered to host utilities and other program participants in the United States and Japan for field testing. The construction of the 46 fully-integrated power plants was completed in January 1985 within the constraints of the contract plan. The program has provided significant experience in the manufacture, acceptance testing, deployment, and support of on-site fuel cell systems. Initial field test results also show that these experimental power plants meet the performance and environmental requirements of a commercial specification. This Interim Report encompasses the design and manufacturing phases of the 40 kW Power Plant Manufacturing and Field Test program. The contract between UTC and NASA also provides UTC field engineering support to the host utilities, training programs and associated manuals for utility operating and maintenance personnel, spare parts support for a defined test period, and testing at UTC of a power plant made available from a preceding program phase. These activities are ongoing and will be reported subsequently.

Modeling Mass and Thermal Transport in Thin Porous Media of PEM Fuel Cells

NASA Astrophysics Data System (ADS)

Konduru, Vinaykumar

Water transport in the Porous Transport Layer (PTL) plays an important role in the efficient operation of polymer electrolyte membrane fuel cells (PEMFC). Excessive water content as well as dry operating conditions are unfavorable for efficient and reliable operation of the fuel cell. The effect of thermal conductivity and porosity on water management are investigated by simulating two-phase flow in the PTL of the fuel cell using a network model. In the model, the PTL consists of a pore-phase and a solid-phase. Different models of the PTLs are generated using independent Weibull distributions for the pore-phase and the solid-phase. The specific arrangement of the pores and solid elements is varied to obtain different PTL realizations for the same Weibull parameters. The properties of PTL are varied by changing the porosity and thermal conductivity. The parameters affecting operating conditions include the temperature, relative humidity in the flow channel and voltage and current density. In addition, a novel high-speed capable Surface Plasmon Resonance (SPR) microscope was built based on Kretschmann's configuration utilizing a collimated Kohler illumination. The SPR allows thin film characterization in a thickness of approximately 0-200nm by measuring the changes in the refractive index. Various independent experiments were run to measure film thickness during droplet coalescence during condensation.

40 CFR 600.304-12 - Fuel economy label-special requirements for hydrogen fuel cell vehicles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... requirements for hydrogen fuel cell vehicles. 600.304-12 Section 600.304-12 Protection of Environment... MOTOR VEHICLES Fuel Economy Labeling § 600.304-12 Fuel economy label—special requirements for hydrogen fuel cell vehicles. Fuel economy labels for hydrogen fuel cell vehicles must meet the specifications...

40 CFR 600.304-12 - Fuel economy label-special requirements for hydrogen fuel cell vehicles.

Code of Federal Regulations, 2014 CFR

2014-07-01

... requirements for hydrogen fuel cell vehicles. 600.304-12 Section 600.304-12 Protection of Environment... MOTOR VEHICLES Fuel Economy Labeling § 600.304-12 Fuel economy label—special requirements for hydrogen fuel cell vehicles. Fuel economy labels for hydrogen fuel cell vehicles must meet the specifications...

40 CFR 600.304-12 - Fuel economy label-special requirements for hydrogen fuel cell vehicles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... requirements for hydrogen fuel cell vehicles. 600.304-12 Section 600.304-12 Protection of Environment... MOTOR VEHICLES Fuel Economy Labeling § 600.304-12 Fuel economy label—special requirements for hydrogen fuel cell vehicles. Fuel economy labels for hydrogen fuel cell vehicles must meet the specifications...

Fuel Cell Technology Status Analysis | Hydrogen and Fuel Cells | NREL

Science.gov Websites

Technology Status Analysis Fuel Cell Technology Status Analysis Get Involved Fuel cell developers interested in collaborating with NREL on fuel cell technology status analysis should send an email to NREL's Technology Validation Team at techval@nrel.gov. NREL's analysis of fuel cell technology provides objective

Multi-stage fuel cell system method and apparatus

DOEpatents

George, Thomas J.; Smith, William C.

2000-01-01

A high efficiency, multi-stage fuel cell system method and apparatus is provided. The fuel cell system is comprised of multiple fuel cell stages, whereby the temperatures of the fuel and oxidant gas streams and the percentage of fuel consumed in each stage are controlled to optimize fuel cell system efficiency. The stages are connected in a serial, flow-through arrangement such that the oxidant gas and fuel gas flowing through an upstream stage is conducted directly into the next adjacent downstream stage. The fuel cell stages are further arranged such that unspent fuel and oxidant laden gases too hot to continue within an upstream stage because of material constraints are conducted into a subsequent downstream stage which comprises a similar cell configuration, however, which is constructed from materials having a higher heat tolerance and designed to meet higher thermal demands. In addition, fuel is underutilized in each stage, resulting in a higher overall fuel cell system efficiency.

What utility companies should known about fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirschenhofer, J.H.; Weinstein, R.E.

1996-11-01

Fuel cells are warming up. A world that ten years ago was unaware of the concept now can witness approximately 200 fuel cell units operating in 15 countries. An increasing number of utility company planners and decision makers have begun to ask whether fuel cells might fit into their future. While the fuel cell concept is simple, determining which type of fuel cell to consider may prove taxing. The multiplicity of fuel cells and their development programs, coupled with the amount of subject material and claims-versus-reality, may seem complex. Also to be reckoned with is the changing utility environment thatmore » might portend well for distributed generation with technologies such as fuel cells. This paper provides a road map of major fuel cell development in the US. It offers some views about the impact of the changing utility environment on fuel cells.« less

Multi-mode energy management strategy for fuel cell electric vehicles based on driving pattern identification using learning vector quantization neural network algorithm

NASA Astrophysics Data System (ADS)

Song, Ke; Li, Feiqiang; Hu, Xiao; He, Lin; Niu, Wenxu; Lu, Sihao; Zhang, Tong

2018-06-01

The development of fuel cell electric vehicles can to a certain extent alleviate worldwide energy and environmental issues. While a single energy management strategy cannot meet the complex road conditions of an actual vehicle, this article proposes a multi-mode energy management strategy for electric vehicles with a fuel cell range extender based on driving condition recognition technology, which contains a patterns recognizer and a multi-mode energy management controller. This paper introduces a learning vector quantization (LVQ) neural network to design the driving patterns recognizer according to a vehicle's driving information. This multi-mode strategy can automatically switch to the genetic algorithm optimized thermostat strategy under specific driving conditions in the light of the differences in condition recognition results. Simulation experiments were carried out based on the model's validity verification using a dynamometer test bench. Simulation results show that the proposed strategy can obtain better economic performance than the single-mode thermostat strategy under dynamic driving conditions.

Catalyst supports for polymer electrolyte fuel cells.

PubMed

Subban, Chinmayee; Zhou, Qin; Leonard, Brian; Ranjan, Chinmoy; Edvenson, Heather M; Disalvo, F J; Munie, Semeret; Hunting, Janet

2010-07-28

A major challenge in obtaining long-term durability in fuel cells is to discover catalyst supports that do not corrode, or corrode much more slowly than the current carbon blacks used in today's polymer electrolyte membrane fuel cells. Such materials must be sufficiently stable at low pH (acidic conditions) and high potential, in contact with the polymer membrane and under exposure to hydrogen gas and oxygen at temperatures up to perhaps 120 degrees C. Here, we report the initial discovery of a promising class of doped oxide materials for this purpose: Ti(1-x)M(x)O(2), where M=a variety of transition metals. Specifically, we show that Ti(0.7)W(0.3)O(2) is electrochemically inert over the appropriate potential range. Although the process is not yet optimized, when Pt nanoparticles are deposited on this oxide, electrochemical experiments show that hydrogen is oxidized and oxygen reduced at rates comparable to those seen using a commercial Pt on carbon black support.

Nanophase Nickel-Zirconium Alloys for Fuel Cells

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram; Whitacre, jay; Valdez, Thomas

2008-01-01

Nanophase nickel-zirconium alloys have been investigated for use as electrically conductive coatings and catalyst supports in fuel cells. Heretofore, noble metals have been used because they resist corrosion in the harsh, acidic fuel cell interior environments. However, the high cost of noble metals has prompted a search for less-costly substitutes. Nickel-zirconium alloys belong to a class of base metal alloys formed from transition elements of widely different d-electron configurations. These alloys generally exhibit unique physical, chemical, and metallurgical properties that can include corrosion resistance. Inasmuch as corrosion is accelerated by free-energy differences between bulk material and grain boundaries, it was conjectured that amorphous (glassy) and nanophase forms of these alloys could offer the desired corrosion resistance. For experiments to test the conjecture, thin alloy films containing various proportions of nickel and zirconium were deposited by magnetron and radiofrequency co-sputtering of nickel and zirconium. The results of x-ray diffraction studies of the deposited films suggested that the films had a nanophase and nearly amorphous character.

Fuzzy-based failure mode and effect analysis (FMEA) of a hybrid molten carbonate fuel cell (MCFC) and gas turbine system for marine propulsion

NASA Astrophysics Data System (ADS)

Ahn, Junkeon; Noh, Yeelyong; Park, Sung Ho; Choi, Byung Il; Chang, Daejun

2017-10-01

This study proposes a fuzzy-based FMEA (failure mode and effect analysis) for a hybrid molten carbonate fuel cell and gas turbine system for liquefied hydrogen tankers. An FMEA-based regulatory framework is adopted to analyze the non-conventional propulsion system and to understand the risk picture of the system. Since the participants of the FMEA rely on their subjective and qualitative experiences, the conventional FMEA used for identifying failures that affect system performance inevitably involves inherent uncertainties. A fuzzy-based FMEA is introduced to express such uncertainties appropriately and to provide flexible access to a risk picture for a new system using fuzzy modeling. The hybrid system has 35 components and has 70 potential failure modes, respectively. Significant failure modes occur in the fuel cell stack and rotary machine. The fuzzy risk priority number is used to validate the crisp risk priority number in the FMEA.

Efficiency measurement and uncertainty discussion of an electric engine powered by a ``self-breathing'' and ``self-humidified'' proton exchange membrane fuel cell

NASA Astrophysics Data System (ADS)

Schiavetti, Pierluigi; Del Prete, Zaccaria

2007-08-01

The efficiency of an automotive engine based on a "self-breathing" and "self-humidified" proton exchange membrane fuel cell stack (PEM FC) connected to a dc brushless electrical motor was measured under variable power load conditions. Experiments have been carried out on a small scale 150W engine model. After determining the fuel cell static polarization curve and the time response to power steps, the system was driven to copy on the test bench a "standard urban load cycle" and its instantaneous efficiencies were measured at an acquisition rate of 5Hz. The integral system efficiency over the entire urban load cycle, comprising the losses of the unavoidable auxiliary components of the engine, was then calculated. The fuel cell stack was operated mainly in "partial" dead-end mode, with a periodic anode flow channel purging, and one test was carried out in "pure" dead-end mode, with no anode channel purging. An uncertainty analysis of the efficiencies was carried out, taking into account either type A and type B evaluation methods, strengthening the discussion about the outcomes obtained for a system based on this novel simplified FC type. For our small scale engine we measured over the standard urban cycle, on the basis of the H2 high heating value (HHV), a tank-to-wheel integral efficiency of (18.2±0.8)%, when the fuel cell was operated with periodic flow channel purging, and of (21.5±1.3)% in complete dead-end operation mode.

Center for Fuel Cell Research and Applications development phase. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-12-01

The deployment and operation of clean power generation is becoming critical as the energy and transportation sectors seek ways to comply with clean air standards and the national deregulation of the utility industry. However, for strategic business decisions, considerable analysis is required over the next few years to evaluate the appropriate application and value added from this emerging technology. To this end the Houston Advanced Research Center (HARC) is proposing a three-year industry-driven project that centers on the creation of ``The Center for Fuel Cell Research and Applications.`` A collaborative laboratory housed at and managed by HARC, the Center willmore » enable a core group of six diverse participating companies--industry participants--to investigate the economic and operational feasibility of proton-exchange-membrane (PEM) fuel cells in a variety of applications (the core project). This document describes the unique benefits of a collaborative approach to PEM applied research, among them a shared laboratory concept leading to cost savings and shared risks as well as access to outstanding research talent and lab facilities. It also describes the benefits provided by implementing the project at HARC, with particular emphasis on HARC`s history of managing successful long-term research projects as well as its experience in dealing with industry consortia projects. The Center is also unique in that it will not duplicate the traditional university role of basic research or that of the fuel cell industry in developing commercial products. Instead, the Center will focus on applications, testing, and demonstration of fuel cell technology.« less

Efficiency measurement and uncertainty discussion of an electric engine powered by a "self-breathing" and "self-humidified" proton exchange membrane fuel cell.

PubMed

Schiavetti, Pierluigi; Del Prete, Zaccaria

2007-08-01

The efficiency of an automotive engine based on a "self-breathing" and "self-humidified" proton exchange membrane fuel cell stack (PEM FC) connected to a dc brushless electrical motor was measured under variable power load conditions. Experiments have been carried out on a small scale 150 W engine model. After determining the fuel cell static polarization curve and the time response to power steps, the system was driven to copy on the test bench a "standard urban load cycle" and its instantaneous efficiencies were measured at an acquisition rate of 5 Hz. The integral system efficiency over the entire urban load cycle, comprising the losses of the unavoidable auxiliary components of the engine, was then calculated. The fuel cell stack was operated mainly in "partial" dead-end mode, with a periodic anode flow channel purging, and one test was carried out in "pure" dead-end mode, with no anode channel purging. An uncertainty analysis of the efficiencies was carried out, taking into account either type A and type B evaluation methods, strengthening the discussion about the outcomes obtained for a system based on this novel simplified FC type. For our small scale engine we measured over the standard urban cycle, on the basis of the H(2) high heating value (HHV), a tank-to-wheel integral efficiency of (18.2+/-0.8)%, when the fuel cell was operated with periodic flow channel purging, and of (21.5+/-1.3)% in complete dead-end operation mode.

Comprehensive characterization and understanding of micro-fuel cells operating at high methanol concentrations.

PubMed

Gago, Aldo S; Esquivel, Juan-Pablo; Sabaté, Neus; Santander, Joaquín; Alonso-Vante, Nicolas

2015-01-01

We report on the analysis of the performance of each electrode of an air-breathing passive micro-direct methanol fuel cell (µDMFC) during polarization, stabilization and discharge, with CH3OH (2-20 M). A reference electrode with a microcapillary was used for separately measuring the anode the cathode potential. Information about the open circuit potential (OCP), the voltage and the mass transport related phenomena are available. Using 2 M CH3OH, the anode showed mass transport problems. With 4 and 6 M CH3OH both electrodes experience this situation, whereas with 10 and 20 M CH3OH the issue is attributed to the cathode. The stabilization and fuel consumption time depends mainly on the cathode performance, which is very sensitive to fuel crossover. The exposure to 20 M CH3OH produced a loss in performance of more than 75% of the highest power density (16.3 mW·cm(-2)).

Method of improving fuel cell performance by removing at least one metal oxide contaminant from a fuel cell electrode

DOEpatents

Kim, Yu Seung [Los Alamos, NM; Choi, Jong-Ho [Los Alamos, NM; Zelenay, Piotr [Los Alamos, NM

2009-08-18

A method of removing contaminants from a fuel cell catalyst electrode. The method includes providing a getter electrode and a fuel cell catalyst electrode having at least one contaminant to a bath and applying a voltage sufficient to drive the contaminant from the fuel cell catalyst electrode to the getter electrode. Methods of removing contaminants from a membrane electrode assembly of a fuel cell and of improving performance of a fuel cell are also provided.

Air Breathing Direct Methanol Fuel Cell

DOEpatents

Ren; Xiaoming

2003-07-22

A method for activating a membrane electrode assembly for a direct methanol fuel cell is disclosed. The method comprises operating the fuel cell with humidified hydrogen as the fuel followed by running the fuel cell with methanol as the fuel.

Using Polymer Electrolyte Membrane Fuel Cells in a Hybrid Surface Ship Propulsion Plant to Increase Fuel Efficiency

DTIC Science & Technology

2010-06-01

cell ( PEMFC ), and the phosphoric acid fuel cell (PAFC). 2.3.1 Solid Oxide Fuel Cells (SOFC) The first type of fuel cell considered is the SOFC. This...durability issues for use within a given application. 2.3.2 Polymer Electrolyte Membrane Fuel Cells ( PEMFC ) The PEMFC operates by passing hydrogen that has...cells. Some advantages of PEMFC operating at such low temperatures is that the fuel cell doesn’t require as meticulous of a support system infrastructure

Investigation of the degradation of different nickel anode types for alkaline fuel cells (AFCs)

NASA Astrophysics Data System (ADS)

Gülzow, E.; Schulze, M.; Steinhilber, G.

Alkaline fuel cells (AFCs) have the opportunity of becoming important for mobile energy systems as, in contrast to other low temperature fuel cells, the alkaline type requires neither noble metal catalysts nor an expensive polymer electrolyte. In AFCs, nickel is used as anode catalyst in gas diffusion electrodes. The metal catalyst was mixed with polytetraflourethylene (PTFE) as organic binder in a knife mile and rolled onto a metal web in a calendar to prepare the electrode. After an activation process with hydrogen evolution at 5 mA/cm 2 for 18 h, the electrodes were stressed at constant loading in a half cell equipment. During the fuel cell operation, the electrochemical performance decreased due to changes of the polymer (PTFE) and of the metal particles in the electrode, which is described in detail in another paper. In this study, three types of electrodes were investigated. The first type of electrode is composed of pure Raney-nickel and PTFE powder, the nickel particles in the second electrode type were selected according to particle size and in the third electrode copper powder was added to the nickel powder not selected by size. The size selected nickel particles show a better electrochemical performance related to the non-selected catalyst, but due to the electrochemically induced disintegration of the nickel particles the electrochemical performance decreases stronger. The copper powder in the third electrode is added to improve the electronic conductivity of the nickel catalyst, but the copper is not stable under the electrochemical conditions in fuel cell operation. With all three anode types long-term experiments have been performed. The electrodes have been characterized after the electrochemical stressing to investigate the degradation processes.

Hydrogen production from bio-fuels using precious metal catalysts

NASA Astrophysics Data System (ADS)

Pasel, Joachim; Wohlrab, Sebastian; Rotov, Mikhail; Löhken, Katrin; Peters, Ralf; Stolten, Detlef

2017-11-01

Fuel cell systems with integrated autothermal reforming unit require active and robust catalysts for H2 production. Thus, an experimental screening of catalysts for autothermal reforming of commercial biodiesel fuel was performed. Catalysts consisted of a monolithic cordierite substrate, an oxide support (γ-Al2O3) and Pt, Ru, Ni, PtRh and PtRu as active phase. Experiments were run by widely varying the O2/C and H2O/C molar ratios at different gas hourly space velocities. Fresh and aged catalysts were characterized by temperature programmed methods and thermogravimetry to find correlations with catalytic activity and stability.

Alternative Fuels Data Center: Hydrogen Fuel Cell Electric Vehicle

Science.gov Websites

Data Center: Hydrogen Fuel Cell Electric Vehicle Availability to someone by E-mail Share Alternative Fuels Data Center: Hydrogen Fuel Cell Electric Vehicle Availability on Facebook Tweet about Alternative Fuels Data Center: Hydrogen Fuel Cell Electric Vehicle Availability on Twitter Bookmark Alternative

Highly durable, coking and sulfur tolerant, fuel-flexible protonic ceramic fuel cells.

PubMed

Duan, Chuancheng; Kee, Robert J; Zhu, Huayang; Karakaya, Canan; Chen, Yachao; Ricote, Sandrine; Jarry, Angelique; Crumlin, Ethan J; Hook, David; Braun, Robert; Sullivan, Neal P; O'Hayre, Ryan

2018-05-01

Protonic ceramic fuel cells, like their higher-temperature solid-oxide fuel cell counterparts, can directly use both hydrogen and hydrocarbon fuels to produce electricity at potentially more than 50 per cent efficiency 1,2 . Most previous direct-hydrocarbon fuel cell research has focused on solid-oxide fuel cells based on oxygen-ion-conducting electrolytes, but carbon deposition (coking) and sulfur poisoning typically occur when such fuel cells are directly operated on hydrocarbon- and/or sulfur-containing fuels, resulting in severe performance degradation over time 3-6 . Despite studies suggesting good performance and anti-coking resistance in hydrocarbon-fuelled protonic ceramic fuel cells 2,7,8 , there have been no systematic studies of long-term durability. Here we present results from long-term testing of protonic ceramic fuel cells using a total of 11 different fuels (hydrogen, methane, domestic natural gas (with and without hydrogen sulfide), propane, n-butane, i-butane, iso-octane, methanol, ethanol and ammonia) at temperatures between 500 and 600 degrees Celsius. Several cells have been tested for over 6,000 hours, and we demonstrate excellent performance and exceptional durability (less than 1.5 per cent degradation per 1,000 hours in most cases) across all fuels without any modifications in the cell composition or architecture. Large fluctuations in temperature are tolerated, and coking is not observed even after thousands of hours of continuous operation. Finally, sulfur, a notorious poison for both low-temperature and high-temperature fuel cells, does not seem to affect the performance of protonic ceramic fuel cells when supplied at levels consistent with commercial fuels. The fuel flexibility and long-term durability demonstrated by the protonic ceramic fuel cell devices highlight the promise of this technology and its potential for commercial application.

Annular feed air breathing fuel cell stack

DOEpatents

Wilson, Mahlon S.; Neutzler, Jay K.

1997-01-01

A stack of polymer electrolyte fuel cells is formed from a plurality of unit cells where each unit cell includes fuel cell components defining a periphery and distributed along a common axis, where the fuel cell components include a polymer electrolyte membrane, an anode and a cathode contacting opposite sides of the membrane, and fuel and oxygen flow fields contacting the anode and the cathode, respectively, wherein the components define an annular region therethrough along the axis. A fuel distribution manifold within the annular region is connected to deliver fuel to the fuel flow field in each of the unit cells. The fuel distribution manifold is formed from a hydrophilic-like material to redistribute water produced by fuel and oxygen reacting at the cathode. In a particular embodiment, a single bolt through the annular region clamps the unit cells together. In another embodiment, separator plates between individual unit cells have an extended radial dimension to function as cooling fins for maintaining the operating temperature of the fuel cell stack.

CERDEC Fuel Cell Team: Military Transitions for Soldier Fuel Cells

DTIC Science & Technology

2008-10-27

Fuel Cell (DMFC) (PEO Soldier) Samsung: 20W DMFC (CRADA) General Atomics & Jadoo: 50W Ammonia Borane Fueled PEMFC Current Fuel Cell Team Efforts...Continued Ardica: 20W Wearable PEMFC operating on Chemical Hydrides Spectrum Brands w/ Rayovac: Hydrogen Generators and Alkaline Fuel Cells for AA...100W Ammonia Borane fueled PEMFC Ultralife: 150W sodium borohydride fueled PEMFC Protonex: 250W RMFC and Power Manager (ARO) NanoDynamics: 250W SOFC

Methods for continuous direct carbon fuel cell operation with a circulating electrolyte slurry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harjes, Daniel I.; Dineen, Jr., D. Andrew; Guo, Liang

The present invention relates to methods and systems related to fuel cells, and in particular, to direct carbon fuel cells. The methods and systems relate to cleaning and removal of components utilized and produced during operation of the fuel cell, regeneration of components utilized during operation of the fuel cell, and generating power using the fuel cell.

Fuel cells for commercial energy

NASA Astrophysics Data System (ADS)

Huppmann, Gerhard; Weisse, Eckart; Bischoff, Manfred

1990-04-01

The development of various types of fuel cells is described. Advantges and drawbacks are considered for alkaline fuel cells, phosphoric acid fuel cells, and molten carbonate fuel cells. It is shown that their modular construction is particularly adapted to power heat systems. A comparison which is largely in favor of fuel cells, is made between coal, oil, natural gas power stations, and fuel cells. Safety risks in operation are also compared with those of conventional power stations. Fuel cells are particularly suited for dwellings, shopping centers, swimming pools, other sporting installations, and research facilities, whose high current and heat requirements can be covered by power heat coupling.

Chitosan biopolymer for fuel cell applications.

PubMed

Ma, Jia; Sahai, Yogeshwar

2013-02-15

Fuel cell is an electrochemical device which converts chemical energy stored in a fuel into electrical energy. Fuel cells have been receiving attention due to its potential applicability as a good alternative power source. Recently, cost-effective and eco-friendly biopolymer chitosan has been extensively studied as a material for membrane electrolytes and electrodes in low to intermediate temperature hydrogen polymer electrolyte fuel cell, direct methanol fuel cell, alkaline fuel cell, and biofuel cell. This paper reviews structure and property of chitosan with respect to its applications in fuel cells. Recent achievements and prospect of its applications have also been included. Copyright © 2012 Elsevier Ltd. All rights reserved.

Fuel Cells for Space Science Applications

NASA Technical Reports Server (NTRS)

Burke, Kenneth A.

2003-01-01

Fuel cell technology has been receiving more attention recently as a possible alternative to the internal combustion engine for our automobile. Improvements in fuel cell designs as well as improvements in lightweight high-pressure gas storage tank technology make fuel cell technology worth a look to see if fuel cells can play a more expanded role in space missions. This study looks at the specific weight density and specific volume density of potential fuel cell systems as an alternative to primary and secondary batteries that have traditionally been used for space missions. This preliminary study indicates that fuel cell systems have the potential for energy densities of greater than 500 W-hr/kg, greater than 500W/kg and greater than 400 W-hr/liter, greater than 200 W/liter. This level of performance makes fuel cells attractive as high-power density, high-energy density sources for space science probes, planetary rovers and other payloads. The power requirements for these space missions are, in general, much lower than the power levels where fuel cells have been used in the past. Adaptation of fuel cells for space science missions will require down-sizing the fuel cell stack and making the fuel cell operate without significant amounts of ancillary equipment.

Bootstrapping a Sustainable North American PEM Fuel Cell Industry: Could a Federal Acquisition Program Make a Difference?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greene, David L; Duleep, Dr. K. G.

2008-10-01

The North American Proton Exchange Membrane (PEM) fuel cell industry may be at a critical juncture. A large-scale market for automotive fuel cells appears to be several years away and in any case will require a long-term, coordinated commitment by government and industry to insure the co-evolution of hydrogen infrastructure and fuel cell vehicles (Greene et al., 2008). The market for non-automotive PEM fuel cells, on the other hand, may be much closer to commercial viability (Stone, 2006). Cost targets are less demanding and manufacturers appear to be close, perhaps within a factor of two, of meeting them. Hydrogen supplymore » is a significant obstacle to market acceptance but may not be as great a barrier as it is for hydrogen-powered vehicles due to the smaller quantities of hydrogen required. PEM fuel cells appear to be potentially competitive in two markets: (1) Backup power (BuP) supply, and (2) electrically-powered MHE (Mahadevan et al., 2007a, 2007b). There are several Original Equipment Manufacturers (OEMs) of PEM fuel cell systems for these applications but production levels have been quite low (on the order of 100-200 per year) and cumulative production experience is also limited (on the order of 1,000 units to date). As a consequence, costs remain above target levels and PEM fuel cell OEMs are not yet competitive in these markets. If cost targets can be reached and acceptable solutions to hydrogen supply found, a sustainable North American PEM fuel cell industry could be established. If not, the industry and its North American supply chain could disappear within a year or two. The Hydrogen Fuel Cell and Infrastructure Technologies (HFCIT) program of the U.S. Department of Energy (DOE) requested a rapid assessment of the potential for a government acquisition program to bootstrap the market for non-automotive PEM fuel cells by driving down costs via economies of scale and learning-by-doing. The six week study included in-depth interviews of three manufacturers, visits to two production facilities, review of the literature on potential markets in North America and potential federal government procurements, development of a cost model reflecting economies of scale and learning-by-doing, and estimation of the impact of federal PEM fuel cell procurements on fuel cell system costs and the evolution of private market demand. This report presents the findings of that study. Section 2 outlines the status of the industry and describes potential markets based on interviews of manufacturers and the existing literature. Section 3 describes the modeling methodology including key premises and assumptions, and presents estimates of market evolution under four scenarios: (1) Base Case with no federal government procurement program, (2) Scenario 1, an aggressive program beginning with less than 200 units procured in 2008 ramping up to more than 2,000 units in 2012, (3) Scenario 2 which is identical to Scenario 1 except that the private market is assumed to be twice as sensitive to price, and (4) Scenario 3, a delayed, smaller federal procurement program beginning in 2011 increasing to a maximum of just over 1,000 units per year in 2012. The analysis suggests that the aggressive program of Scenario 1 would likely stimulate a sustainable, competitive North American non-automotive PEM fuel cell industry. Given plausible assumptions about learning rates and scale economies, the procurements assumed in Scenario 1 appear to be sufficient to drive down costs to target levels. These findings are conditional on the evolution of acceptable hydrogen supply strategies, which were not explicitly analyzed in this study. Success is less certain under Scenarios 2 and 3, and there appears to be a strong probability that existing OEMs would not survive until 2011. In the Base Case, no program, a viable North American industry does not emerge before 2020.« less

Massachusetts Fuel Cell Bus Project: Demonstrating a Total Transit Solution for Fuel Cell Electric Buses in Boston

DOE Office of Scientific and Technical Information (OSTI.GOV)

The Federal Transit Administration's National Fuel Cell Bus Program focuses on developing commercially viable fuel cell bus technologies. Nuvera is leading the Massachusetts Fuel Cell Bus project to demonstrate a complete transit solution for fuel cell electric buses that includes one bus and an on-site hydrogen generation station for the Massachusetts Bay Transportation Authority (MBTA). A team consisting of ElDorado National, BAE Systems, and Ballard Power Systems built the fuel cell electric bus, and Nuvera is providing its PowerTap on-site hydrogen generator to provide fuel for the bus.

Interconnection of bundled solid oxide fuel cells

DOEpatents

Brown, Michael; Bessette, II, Norman F; Litka, Anthony F; Schmidt, Douglas S

2014-01-14

A system and method for electrically interconnecting a plurality of fuel cells to provide dense packing of the fuel cells. Each one of the plurality of fuel cells has a plurality of discrete electrical connection points along an outer surface. Electrical connections are made directly between the discrete electrical connection points of adjacent fuel cells so that the fuel cells can be packed more densely. Fuel cells have at least one outer electrode and at least one discrete interconnection to an inner electrode, wherein the outer electrode is one of a cathode and and anode and wherein the inner electrode is the other of the cathode and the anode. In tubular solid oxide fuel cells the discrete electrical connection points are spaced along the length of the fuel cell.

Nonhumidified High-Temperature Membranes Developed for Proton Exchange Membrane Fuel Cells

NASA Technical Reports Server (NTRS)

Kinder, James D.

2005-01-01

Fuel cells are being considered for a wide variety of aerospace applications. One of the most versatile types of fuel cells is the proton-exchange-membrane (PEM) fuel cell. PEM fuel cells can be easily scaled to meet the power and space requirements of a specific application. For example, small 100-W PEM fuel cells are being considered for personal power for extravehicular activity suit applications, whereas larger PEM fuel cells are being designed for primary power in airplanes and in uninhabited air vehicles. Typically, PEM fuel cells operate at temperatures up to 80 C. To increase the efficiency and power density of the fuel cell system, researchers are pursuing methods to extend the operating temperature of the PEM fuel cell to 180 C. The most widely used membranes in PEM fuel cells are Nafion 112 and Nafion 117--sulfonated perfluorinated polyethers that were developed by DuPont. In addition to their relatively high cost, the properties of these membranes limit their use in a PEM fuel cell to around 80 C. The proton conductivity of Nafion membranes significantly decreases above 80 C because the membrane dehydrates. The useful operating range of Nafion-based PEM fuel cells can be extended to over 100 C if ancillary equipment, such as compressors and humidifiers, is added to maintain moisture levels within the membrane. However, the addition of these components reduces the power density and increases the complexity of the fuel cell system.

Develop and test fuel cell powered on-site integrated total energy systems. Phase 3: Full-scale power plant development

NASA Technical Reports Server (NTRS)

Feigenbaum, H.; Kaufman, A.; Wang, C. L.; Werth, J.; Whelan, J. A.

1983-01-01

Operating experience with a 5kW methanol-air integrated system is described. On-going test results for a 24-cell, two-sq ft (4kW) stack are reported. The main activity for this stack is currently the evaluation of developmental non-metalic cooling plates. Single-cell test results are presented for a promising developmental cathode catalyst.

Microfluidic fuel cell systems

NASA Astrophysics Data System (ADS)

Ho, Bernard; Kjeang, Erik

2011-06-01

A microfluidic fuel cell is a microfabricated device that produces electrical power through electrochemical reactions involving a fuel and an oxidant. Microfluidic fuel cell systems exploit co-laminar flow on the microscale to separate the fuel and oxidant species, in contrast to conventional fuel cells employing an ion exchange membrane for this function. Since 2002 when the first microfluidic fuel cell was invented, many different fuels, oxidants, and architectures have been investigated conceptually and experimentally. In this mini-review article, recent advancements in the field of microfluidic fuel cell systems are documented, with particular emphasis on design, operation, and performance. The present microfluidic fuel cell systems are categorized by the fluidic phases of the fuel and oxidant streams, featuring gaseous/gaseous, liquid/gaseous, and liquid/liquid systems. The typical cell configurations and recent contributions in each category are analyzed. Key research challenges and opportunities are highlighted and recommendations for further work are provided.

Fundamentals of fuel cell system integration

NASA Astrophysics Data System (ADS)

Krumpelt, Michael; Kumar, Romesh; Myles, Kevin M.

1994-04-01

Fuel cells are theoretically very efficient energy conversion devices that have the potential of becoming a commercial product for numerous uses in the civilian economy. We have analyzed several fuel cell system designs with regard to thermal and chemical integration of the fuel cell stack into the rest of the system. Thermal integration permits the use of the stack waste heat for the endothermic steps of fuel reforming. Chemical integration provides the steam needed for fuel reforming from the water produced by the electrochemical cell reaction. High-temperature fuel cells, such as the molten carbonate and the solid oxide fuel cells, permit this system integration in a relatively simple manner. Lower temperature fuel cells, such as the polymer electrolyte and phosphoric acid systems, require added system complexity to achieve such integration. The system economics are affected by capital and fuel costs and technical parameters, such as electrochemical fuel utilization, current density, and system complexity. At today's low fuel prices and the high fuel cell costs (in part, because of the low rates of production of the early prototypes), fuel cell systems are not cost competitive with conventional power generation. With the manufacture and sale of larger numbers of fuel cell systems, the total costs will decrease from the current several thousand dollars per kW, to perhaps less than $100 per kW as production volumes approa ch a million units per year.

Molten Carbonate Fuel Cell Operation With Dual Fuel Flexibility

DTIC Science & Technology

2007-10-01

electrolyte membrane fuel cell ( PEMFC ). At the higher operating temperature, fuel reforming of natural gas can occur internally, eliminating the need...oxygen PAFC Phosphoric Acid Fuel Cell PEMFC Polymer Electrolyte Membrane Fuel Cell PDS Propane Desulfurization System ppm parts per million psig

The TMI regenerable solid oxide fuel cell

NASA Technical Reports Server (NTRS)

Cable, Thomas L.

1995-01-01

Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. These systems generally consist of photovoltaic solar arrays which operate during sunlight cycles to provide system power and regenerate fuel (hydrogen) via water electrolysis; during dark cycles, hydrogen is converted by the fuel cell into system. The currently preferred configuration uses two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Fuel cell/electrolyzer system simplicity, reliability, and power-to-weight and power-to-volume ratios could be greatly improved if both power production (fuel cell) and power storage (electrolysis) functions can be integrated into a single unit. The Technology Management, Inc. (TMI), solid oxide fuel cell-based system offers the opportunity to both integrate fuel cell and electrolyzer functions into one unit and potentially simplify system requirements. Based an the TMI solid oxide fuel cell (SOPC) technology, the TMI integrated fuel cell/electrolyzer utilizes innovative gas storage and operational concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H2O electrode (SOFC anode/electrolyzer cathode) materials for solid oxide, regenerative fuel cells. Improved H2/H2O electrode materials showed improved cell performance in both fuel cell and electrolysis modes in reversible cell tests. ln reversible fuel cell/electrolyzer mode, regenerative fuel cell efficiencies (ratio of power out (fuel cell mode) to power in (electrolyzer model)) improved from 50 percent (using conventional electrode materials) to over 80 percent. The new materials will allow the TMI SOFC system to operate as both the electrolyzer and fuel cell in a single unit. Preliminary system designs have also been developed which indicate the technical feasibility of using the TMI SOFC technology for space applications with high energy storage efficiencies and high specific energy. Development of small space systems would also have potential dual-use, terrestrial applications.

The TMI regenerable solid oxide fuel cell

NASA Astrophysics Data System (ADS)

Cable, Thomas L.

1995-04-01

Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. These systems generally consist of photovoltaic solar arrays which operate during sunlight cycles to provide system power and regenerate fuel (hydrogen) via water electrolysis; during dark cycles, hydrogen is converted by the fuel cell into system. The currently preferred configuration uses two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Fuel cell/electrolyzer system simplicity, reliability, and power-to-weight and power-to-volume ratios could be greatly improved if both power production (fuel cell) and power storage (electrolysis) functions can be integrated into a single unit. The Technology Management, Inc. (TMI), solid oxide fuel cell-based system offers the opportunity to both integrate fuel cell and electrolyzer functions into one unit and potentially simplify system requirements. Based an the TMI solid oxide fuel cell (SOPC) technology, the TMI integrated fuel cell/electrolyzer utilizes innovative gas storage and operational concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H2O electrode (SOFC anode/electrolyzer cathode) materials for solid oxide, regenerative fuel cells. Improved H2/H2O electrode materials showed improved cell performance in both fuel cell and electrolysis modes in reversible cell tests. ln reversible fuel cell/electrolyzer mode, regenerative fuel cell efficiencies (ratio of power out (fuel cell mode) to power in (electrolyzer model)) improved from 50 percent (using conventional electrode materials) to over 80 percent. The new materials will allow the TMI SOFC system to operate as both the electrolyzer and fuel cell in a single unit. Preliminary system designs have also been developed which indicate the technical feasibility of using the TMI SOFC technology for space applications with high energy storage efficiencies and high specific energy. Development of small space systems would also have potential dual-use, terrestrial applications.

Fuel Cell Propulsion Systems for an All-electric Personal Air Vehicle

NASA Technical Reports Server (NTRS)

Kohout, Lisa L.; Schmitz, Paul C.

2003-01-01

There is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane and solid oxide fuel cells, alternative fuels and fuel processing, and fuel storage. This paper summarizes the results of a first-order feasibility study for an all-electric personal air vehicle utilizing a fuel cell-powered propulsion system. A representative aircraft with an internal combustion engine was chosen as a baseline to provide key parameters to the study, including engine power and subsystem mass, fuel storage volume and mass, and aircraft range. The engine, fuel tank, and associated ancillaries were then replaced with a fuel cell subsystem. Various configurations were considered including: a proton exchange membrane (PEM) fuel cell with liquid hydrogen storage; a direct methanol PEM fuel cell; and a direct internal reforming solid oxide fuel cell (SOFC)/turbine hybrid system using liquid methane fuel. Each configuration was compared to the baseline case on a mass and range basis.

Fuel Cell Propulsion Systems for an All-Electric Personal Air Vehicle

NASA Technical Reports Server (NTRS)

Kohout, Lisa L.

2003-01-01

There is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane and solid oxide fuel cells, alternative fuels and fuel processing, and fuel storage. This paper summarizes the results of a first-order feasibility study for an all-electric personal air vehicle utilizing a fuel cell-powered propulsion system. A representative aircraft with an internal combustion engine was chosen as a baseline to provide key parameters to the study, including engine power and subsystem mass, fuel storage volume and mass, and aircraft range. The engine, fuel tank, and associated ancillaries were then replaced with a fuel cell subsystem. Various configurations were considered including: a proton exchange membrane (PEM) fuel cell with liquid hydrogen storage; a direct methanol PEM fuel cell; and a direct internal reforming solid oxide fuel cell (SOFC)/turbine hybrid system using liquid methane fuel. Each configuration was compared to the baseline case on a mass and range basis.

Florida Hydrogen Initiative

DOE Office of Scientific and Technical Information (OSTI.GOV)

Block, David L

2013-06-30

The Florida Hydrogen Initiative (FHI) was a research, development and demonstration hydrogen and fuel cell program. The FHI program objectives were to develop Florida?s hydrogen and fuel cell infrastructure and to assist DOE in its hydrogen and fuel cell activities The FHI program funded 12 RD&D projects as follows: Hydrogen Refueling Infrastructure and Rental Car Strategies -- L. Lines, Rollins College This project analyzes strategies for Florida's early stage adaptation of hydrogen-powered public transportation. In particular, the report investigates urban and statewide network of refueling stations and the feasibility of establishing a hydrogen rental-car fleet based in Orlando. Methanol Fuelmore » Cell Vehicle Charging Station at Florida Atlantic University ? M. Fuchs, EnerFuel, Inc. The project objectives were to design, and demonstrate a 10 kWnet proton exchange membrane fuel cell stationary power plant operating on methanol, to achieve an electrical energy efficiency of 32% and to demonstrate transient response time of less than 3 milliseconds. Assessment of Public Understanding of the Hydrogen Economy Through Science Center Exhibits, J. Newman, Orlando Science Center The project objective was to design and build an interactive Science Center exhibit called: ?H2Now: the Great Hydrogen Xchange?. On-site Reformation of Diesel Fuel for Hydrogen Fueling Station Applications ? A. Raissi, Florida Solar Energy Center This project developed an on-demand forecourt hydrogen production technology by catalytically converting high-sulfur hydrocarbon fuels to an essentially sulfur-free gas. The removal of sulfur from reformate is critical since most catalysts used for the steam reformation have limited sulfur tolerance. Chemochromic Hydrogen Leak Detectors for Safety Monitoring ? N. Mohajeri and N. Muradov, Florida Solar Energy Center This project developed and demonstrated a cost-effective and highly selective chemochromic (visual) hydrogen leak detector for safety monitoring at any facility engaged in transport, handling and use of hydrogen. Development of High Efficiency Low Cost Electrocatalysts for Hydrogen Production and PEM Fuel Cell Applications ? M. Rodgers, Florida Solar Energy Center The objective of this project was to decrease platinum usage in fuel cells by conducting experiments to improve catalyst activity while lowering platinum loading through pulse electrodeposition. Optimum values of several variables during electrodeposition were selected to achieve the highest electrode performance, which was related to catalyst morphology. Understanding Mechanical and Chemical Durability of Fuel Cell Membrane Electrode Assemblies ? D. Slattery, Florida Solar Energy Center The objective of this project was to increase the knowledge base of the degradation mechanisms for membranes used in proton exchange membrane fuel cells. The results show the addition of ceria (cerium oxide) has given durability improvements by reducing fluoride emissions by an order of magnitude during an accelerated durability test. Production of Low-Cost Hydrogen from Biowaste (HyBrTec?) ? R. Parker, SRT Group, Inc., Miami, FL This project developed a hydrogen bromide (HyBrTec?) process which produces hydrogen bromide from wet-cellulosic waste and co-produces carbon dioxide. Eelectrolysis dissociates hydrogen bromide producing recyclable bromine and hydrogen. A demonstration reactor and electrolysis vessel was designed, built and operated. Development of a Low-Cost and High-Efficiency 500 W Portable PEMFC System ? J. Zheng, Florida State University, H. Chen, Bing Energy, Inc. The objectives of this project were to develop a new catalyst structures comprised of highly conductive buckypaper and Pt catalyst nanoparticles coated on its surface and to demonstrate fuel cell efficiency improvement and durability and cell cost reductions in the buckypaper based electrodes. Development of an Interdisciplinary Hydrogen and Fuel Cell Technology Academic Program ? J. Politano, Florida Institute of Technology, Melbourne, FL This project developed a hydrogen and fuel cell technology academic program at Florida Institute of Technology in Melbourne, Florida. Design and Development of an Advanced Hydrogen Storage System using Novel Materials ? E. Stefanakos, University of South Florida The goal of this project was to design and develop novel conducting polymeric nanomaterials for on-board hydrogen storage. The project approach was to examine synthesis of polyaniline solid state hydrogen storage materials. Advanced HiFoil ? Bipolar Plates ? J. Braun, M. Fuchs, EnerFuel, Inc. The goal of this project was to provide a durable, low cost bipolar plate for high temperature proton exchange membrane fuel cells. The project results produced a durable, low cost bipolar plate with very high in-plane thermal conductivity.« less

NASA PEMFC Development Background and History

NASA Technical Reports Server (NTRS)

Hoberecht, Mark

2011-01-01

NASA has been developing proton-exchange-membrane (PEM) fuel cell power systems for the past decade, as an upgraded technology to the alkaline fuel cells which presently provide power for the Shuttle Orbiter. All fuel cell power systems consist of one or more fuel cell stacks in combination with appropriate balance-of-plant hardware. Traditional PEM fuel cells are characterized as flow-through, in which recirculating reactant streams remove product water from the fuel cell stack. NASA recently embarked on the development of non-flow-through fuel cell systems, in which reactants are dead-ended into the fuel cell stack and product water is removed by internal wicks. This simplifies the fuel cell power system by eliminating the need for pumps to provide reactant circulation, and mechanical water separators to remove the product water from the recirculating reactant streams. By eliminating these mechanical components, the resulting fuel cell power system has lower mass, volume, and parasitic power requirements, along with higher reliability and longer life. Four vendors have designed and fabricated non-flow-through fuel cell stacks under NASA funding. One of these vendors is considered the "baseline" vendor, and the remaining three vendors are competing for the "alternate" role. Each has undergone testing of their stack hardware integrated with a NASA balance-of-plant. Future Exploration applications for this hardware include primary fuel cells for a Lunar Lander and regenerative fuel cells for Surface Systems.

Miniaturized biological and electrochemical fuel cells: challenges and applications.

PubMed

Yang, Jie; Ghobadian, Sasan; Goodrich, Payton J; Montazami, Reza; Hashemi, Nastaran

2013-09-14

This paper discusses the fundamentals and developments of miniaturized fuel cells, both biological and electrochemical. An overview of microfluidic fuel cells, miniaturized microbial fuel cells, enzymatic biofuel cells, and implanted biofuel cells in an attempt to provide green energy and to power implanted microdevices is provided. Also, the challenges and applications of each type of fuel cell are discussed in detail. Most recent developments in fuel cell technologies such as novel catalysts, compact designs, and fabrication methods are reviewed.

Cationic Polymers Developed for Alkaline Fuel Cell Applications

DTIC Science & Technology

2015-01-20

into five categories: proton exchange membrane fuel cell ( PEMFC ), alkaline fuel cell (AFC), molten carbonate fuel cell (MCFC), solid oxide fuel...SOFC and PAFC belong to high temperature fuel cell, which can be applied in stationary power generation. PEMFC and AFC belong to low temperature fuel...function of the polymer electrolyte is to serve as electrolyte to transport ions between electrodes. PEMFC uses a polymer as electrolyte and works

Reforming of fuel inside fuel cell generator

DOEpatents

Grimble, Ralph E.

1988-01-01

Disclosed is an improved method of reforming a gaseous reformable fuel within a solid oxide fuel cell generator, wherein the solid oxide fuel cell generator has a plurality of individual fuel cells in a refractory container, the fuel cells generating a partially spent fuel stream and a partially spent oxidant stream. The partially spent fuel stream is divided into two streams, spent fuel stream I and spent fuel stream II. Spent fuel stream I is burned with the partially spent oxidant stream inside the refractory container to produce an exhaust stream. The exhaust stream is divided into two streams, exhaust stream I and exhaust stream II, and exhaust stream I is vented. Exhaust stream II is mixed with spent fuel stream II to form a recycle stream. The recycle stream is mixed with the gaseous reformable fuel within the refractory container to form a fuel stream which is supplied to the fuel cells. Also disclosed is an improved apparatus which permits the reforming of a reformable gaseous fuel within such a solid oxide fuel cell generator. The apparatus comprises a mixing chamber within the refractory container, means for diverting a portion of the partially spent fuel stream to the mixing chamber, means for diverting a portion of exhaust gas to the mixing chamber where it is mixed with the portion of the partially spent fuel stream to form a recycle stream, means for injecting the reformable gaseous fuel into the recycle stream, and means for circulating the recycle stream back to the fuel cells.

Reforming of fuel inside fuel cell generator

DOEpatents

Grimble, R.E.

1988-03-08

Disclosed is an improved method of reforming a gaseous reformable fuel within a solid oxide fuel cell generator, wherein the solid oxide fuel cell generator has a plurality of individual fuel cells in a refractory container, the fuel cells generating a partially spent fuel stream and a partially spent oxidant stream. The partially spent fuel stream is divided into two streams, spent fuel stream 1 and spent fuel stream 2. Spent fuel stream 1 is burned with the partially spent oxidant stream inside the refractory container to produce an exhaust stream. The exhaust stream is divided into two streams, exhaust stream 1 and exhaust stream 2, and exhaust stream 1 is vented. Exhaust stream 2 is mixed with spent fuel stream 2 to form a recycle stream. The recycle stream is mixed with the gaseous reformable fuel within the refractory container to form a fuel stream which is supplied to the fuel cells. Also disclosed is an improved apparatus which permits the reforming of a reformable gaseous fuel within such a solid oxide fuel cell generator. The apparatus comprises a mixing chamber within the refractory container, means for diverting a portion of the partially spent fuel stream to the mixing chamber, means for diverting a portion of exhaust gas to the mixing chamber where it is mixed with the portion of the partially spent fuel stream to form a recycle stream, means for injecting the reformable gaseous fuel into the recycle stream, and means for circulating the recycle stream back to the fuel cells. 1 fig.

Alkaline fuel cells for the regenerative fuel cell energy storage system

NASA Technical Reports Server (NTRS)

Martin, R. E.

1983-01-01

The development of the alkaline Regenerative Fuel Cell System, whose fuel cell module would be a derivative of the 12-kW fuel cell power plant currently being produced for the Space Shuttle Orbiter, is reviewed. Long-term endurance testing of full-size fuel cell modules has demonstrated: (1) the extended endurance capability of potassium titanate matrix cells, (2) the long-term performance stability of the anode catalyst, and (3) the suitability of a lightweight graphite structure for use at the anode. These approaches, developed in the NASA-sponsored fuel cell technology advancement program, would also reduce cell weight by nearly one half.

Annular feed air breathing fuel cell stack

DOEpatents

Wilson, Mahlon S.

1996-01-01

A stack of polymer electrolyte fuel cells is formed from a plurality of unit cells where each unit cell includes fuel cell components defining a periphery and distributed along a common axis, where the fuel cell components include a polymer electrolyte membrane, an anode and a cathode contacting opposite sides of the membrane, and fuel and oxygen flow fields contacting the anode and the cathode, respectively, wherein the components define an annular region therethrough along the axis. A fuel distribution manifold within the annular region is connected to deliver fuel to the fuel flow field in each of the unit cells. In a particular embodiment, a single bolt through the annular region clamps the unit cells together. In another embodiment, separator plates between individual unit cells have an extended radial dimension to function as cooling fins for maintaining the operating temperature of the fuel cell stack.

Hydrogen and Fuel Cells | NREL

Science.gov Websites

Cells A hydrogen-powered fuel cell electric vehicle driving past NREL's hydrogen fueling station NREL's hydrogen and fuel cell research and development (R&D) focuses on developing, integrating, and demonstrating hydrogen production and delivery, hydrogen storage, and fuel cell technologies for transportation

Molten carbonate fuel cell separator

DOEpatents

Nickols, Richard C.

1986-09-02

In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.

Molten carbonate fuel cell separator

DOEpatents

Nickols, R.C.

1984-10-17

In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.

High specific power, direct methanol fuel cell stack

DOEpatents

Ramsey, John C [Los Alamos, NM; Wilson, Mahlon S [Los Alamos, NM

2007-05-08

The present invention is a fuel cell stack including at least one direct methanol fuel cell. A cathode manifold is used to convey ambient air to each fuel cell, and an anode manifold is used to convey liquid methanol fuel to each fuel cell. Tie-bolt penetrations and tie-bolts are spaced evenly around the perimeter to hold the fuel cell stack together. Each fuel cell uses two graphite-based plates. One plate includes a cathode active area that is defined by serpentine channels connecting the inlet manifold with an integral flow restrictor to the outlet manifold. The other plate includes an anode active area defined by serpentine channels connecting the inlet and outlet of the anode manifold. Located between the two plates is the fuel cell active region.

INTEGRATED GASIFICATION COMBINED CYCLE PROJECT 2 MW FUEL CELL DEMONSTRATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

FuelCell Energy

2005-05-16

With about 50% of power generation in the United States derived from coal and projections indicating that coal will continue to be the primary fuel for power generation in the next two decades, the Department of Energy (DOE) Clean Coal Technology Demonstration Program (CCTDP) has been conducted since 1985 to develop innovative, environmentally friendly processes for the world energy market place. The 2 MW Fuel Cell Demonstration was part of the Kentucky Pioneer Energy (KPE) Integrated Gasification Combined Cycle (IGCC) project selected by DOE under Round Five of the Clean Coal Technology Demonstration Program. The participant in the CCTDP Vmore » Project was Kentucky Pioneer Energy for the IGCC plant. FuelCell Energy, Inc. (FCE), under subcontract to KPE, was responsible for the design, construction and operation of the 2 MW fuel cell power plant. Duke Fluor Daniel provided engineering design and procurement support for the balance-of-plant skids. Colt Engineering Corporation provided engineering design, fabrication and procurement of the syngas processing skids. Jacobs Applied Technology provided the fabrication of the fuel cell module vessels. Wabash River Energy Ltd (WREL) provided the test site. The 2 MW fuel cell power plant utilizes FuelCell Energy's Direct Fuel Cell (DFC) technology, which is based on the internally reforming carbonate fuel cell. This plant is capable of operating on coal-derived syngas as well as natural gas. Prior testing (1992) of a subscale 20 kW carbonate fuel cell stack at the Louisiana Gasification Technology Inc. (LGTI) site using the Dow/Destec gasification plant indicated that operation on coal derived gas provided normal performance and stable operation. Duke Fluor Daniel and FuelCell Energy developed a commercial plant design for the 2 MW fuel cell. The plant was designed to be modular, factory assembled and truck shippable to the site. Five balance-of-plant skids incorporating fuel processing, anode gas oxidation, heat recovery, water treatment/instrument air, and power conditioning/controls were built and shipped to the site. The two fuel cell modules, each rated at 1 MW on natural gas, were fabricated by FuelCell Energy in its Torrington, CT manufacturing facility. The fuel cell modules were conditioned and tested at FuelCell Energy in Danbury and shipped to the site. Installation of the power plant and connection to all required utilities and syngas was completed. Pre-operation checkout of the entire power plant was conducted and the plant was ready to operate in July 2004. However, fuel gas (natural gas or syngas) was not available at the WREL site due to technical difficulties with the gasifier and other issues. The fuel cell power plant was therefore not operated, and subsequently removed by October of 2005. The WREL fuel cell site was restored to the satisfaction of WREL. FuelCell Energy continues to market carbonate fuel cells for natural gas and digester gas applications. A fuel cell/turbine hybrid is being developed and tested that provides higher efficiency with potential to reach the DOE goal of 60% HHV on coal gas. A system study was conducted for a 40 MW direct fuel cell/turbine hybrid (DFC/T) with potential for future coal gas applications. In addition, FCE is developing Solid Oxide Fuel Cell (SOFC) power plants with Versa Power Systems (VPS) as part of the Solid State Energy Conversion Alliance (SECA) program and has an on-going program for co-production of hydrogen. Future development in these technologies can lead to future coal gas fuel cell applications.« less

Fuel Cell Research and Development for Future NASA Missions

NASA Technical Reports Server (NTRS)

Manzo, Michelle A.; Hoberecht, Mark; Loyselle, Patricia; Burke, Kenneth; Bents, David; Farmer, Serene; Kohout, Lisa

2006-01-01

NASA has been using fuel cell systems since the early days of space flight. Polymer Exchange Membrane Fuel cells provided the primary power for the Gemini and Apollo missions and more recently, alkaline fuel cells serve as the primary power source for the Space Shuttle. NASA's current investments in fuel cell technology support both Exploration and Aeronautics programs. This presentation provides an overview of NASA's fuel cell development programs.

The TMI Regenerative Solid Oxide Fuel Cell

NASA Technical Reports Server (NTRS)

Cable, Thomas L.; Ruhl, Robert C.; Petrik, Michael

1996-01-01

Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. Systems generally consist of photovoltaic solar arrays which operate (during sunlight cycles) to provide system power and regenerate fuel (hydrogen) via water electrolysis and (during dark cycles) fuel cells convert hydrogen into electricity. Common configurations use two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Reliability, power to weight and power to volume ratios could be greatly improved if both power production (fuel cells) and power storage (electrolysis) functions can be integrated into a single unit. The solid oxide fuel cell (SOFC) based design integrates fuel cell and electrolyzer functions and potentially simplifies system requirements. The integrated fuel cell/electrolyzer design also utilizes innovative gas storage concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H20 electrode (SOFC anode/electrolyzer cathode) materials for regenerative fuel cells. Tests have shown improved cell performance in both fuel and electrolysis modes in reversible fuel cell tests. Regenerative fuel cell efficiencies, ratio of power out (fuel cell mode) to power in (electrolyzer mode), improved from 50 percent using conventional electrode materials to over 80 percent. The new materials will allow a single SOFC system to operate as both the electolyzer and fuel cell. Preliminary system designs have also been developed to show the technical feasibility of using the design for space applications requiring high energy storage efficiencies and high specific energy. Small space systems also have potential for dual-use, terrestrial applications.

Hydrogen Fuel Cell Electric Vehicle Learning Demonstration | Hydrogen and

Science.gov Websites

Fuel Cells | NREL Fuel Cell Electric Vehicle Learning Demonstration Hydrogen Fuel Cell Electric Vehicle Learning Demonstration Initiated in 2004, DOE's Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project-later dubbed the Fuel Cell Electric Vehicle (FCEV) Learning Demonstration

Fuel cells: principles, types, fuels, and applications.

PubMed

Carrette, L; Friedrich, K A; Stimming, U

2000-12-15

During the last decade, fuel cells have received enormous attention from research institutions and companies as novel electrical energy conversion systems. In the near future, they will see application in automotive propulsion, distributed power generation, and in low power portable devices (battery replacement). This review gives an introduction into the fundamentals and applications of fuel cells: Firstly, the environmental and social factors promoting fuel cell development are discussed, with an emphasis on the advantages of fuel cells compared to the conventional techniques. Then, the main reactions, which are responsible for the conversion of chemical into electrical energy in fuel cells, are given and the thermodynamic and kinetic fundamentals are stated. The theoretical and real efficiencies of fuel cells are also compared to that of internal combustion engines. Next, the different types of fuel cells and their main components are explained and the related material issues are presented. A section is devoted to fuel generation and storage, which is of paramount importance for the practical aspects of fuel cell use. Finally, attention is given to the integration of the fuel cells into complete systems. © 2000 WILEY-VCH Verlag GmbH, Weinheim, Fed. Rep. of Germany.

Prolonging fuel cell stack lifetime based on Pontryagin's Minimum Principle in fuel cell hybrid vehicles and its economic influence evaluation

NASA Astrophysics Data System (ADS)

Zheng, C. H.; Xu, G. Q.; Park, Y. I.; Lim, W. S.; Cha, S. W.

2014-02-01

The lifetime of fuel cell stacks is a major issue currently, especially for automotive applications. In order to take into account the lifetime of fuel cell stacks while considering the fuel consumption minimization in fuel cell hybrid vehicles (FCHVs), a Pontryagin's Minimum Principle (PMP)-based power management strategy is proposed in this research. This strategy has the effect of prolonging the lifetime of fuel cell stacks. However, there is a tradeoff between the fuel cell stack lifetime and the fuel consumption when this strategy is applied to an FCHV. Verifying the positive economic influence of this strategy is necessary in order to demonstrate its superiority. In this research, the economic influence of the proposed strategy is assessed according to an evaluating cost which is dependent on the fuel cell stack cost, the hydrogen cost, the fuel cell stack lifetime, and the lifetime prolonging impact on the fuel cell stack. Simulation results derived from the proposed power management strategy are also used to evaluate the economic influence. As a result, the positive economic influence of the proposed PMP-based power management strategy is proved for both current and future FCHVs.

Method of forming a package for MEMS-based fuel cell

DOEpatents

Morse, Jeffrey D; Jankowski, Alan F

2013-05-21

A MEMS-based fuel cell package and method thereof is disclosed. The fuel cell package comprises seven layers: (1) a sub-package fuel reservoir interface layer, (2) an anode manifold support layer, (3) a fuel/anode manifold and resistive heater layer, (4) a Thick Film Microporous Flow Host Structure layer containing a fuel cell, (5) an air manifold layer, (6) a cathode manifold support structure layer, and (7) a cap. Fuel cell packages with more than one fuel cell are formed by positioning stacks of these layers in series and/or parallel. The fuel cell package materials such as a molded plastic or a ceramic green tape material can be patterned, aligned and stacked to form three dimensional microfluidic channels that provide electrical feedthroughs from various layers which are bonded together and mechanically support a MEMS-based miniature fuel cell. The package incorporates resistive heating elements to control the temperature of the fuel cell stack. The package is fired to form a bond between the layers and one or more microporous flow host structures containing fuel cells are inserted within the Thick Film Microporous Flow Host Structure layer of the package.

Method of forming a package for mems-based fuel cell

DOEpatents

Morse, Jeffrey D.; Jankowski, Alan F.

2004-11-23

A MEMS-based fuel cell package and method thereof is disclosed. The fuel cell package comprises seven layers: (1) a sub-package fuel reservoir interface layer, (2) an anode manifold support layer, (3) a fuel/anode manifold and resistive heater layer, (4) a Thick Film Microporous Flow Host Structure layer containing a fuel cell, (5) an air manifold layer, (6) a cathode manifold support structure layer, and (7) a cap. Fuel cell packages with more than one fuel cell are formed by positioning stacks of these layers in series and/or parallel. The fuel cell package materials such as a molded plastic or a ceramic green tape material can be patterned, aligned and stacked to form three dimensional microfluidic channels that provide electrical feedthroughs from various layers which are bonded together and mechanically support a MEMOS-based miniature fuel cell. The package incorporates resistive heating elements to control the temperature of the fuel cell stack. The package is fired to form a bond between the layers and one or more microporous flow host structures containing fuel cells are inserted within the Thick Film Microporous Flow Host Structure layer of the package.

Fuel Cells: Reshaping the Future

ERIC Educational Resources Information Center

Toay, Leo

2004-01-01

In conjunction with the FreedomCAR (Cooperative Automotive Research) and Fuel Initiative, President George W. Bush has pledged nearly two billion dollars for fuel cell research. Chrysler, Ford, and General Motors have unveiled fuel cell demonstration vehicles, and all three of these companies have invested heavily in fuel cell research. Fuel cell…

Nicholas J. Grundl | NREL

Science.gov Websites

-3228 Research Interests Application of numerical methods to process problems Fuel and chemical biochemistry and numerical methods), University of Wisconsin at Madison, 2009-2014 Professional Experience Stem Cells Under Defined Conditions," Tissue Engineering Part C Methods (2013)

NREL Fuel Cell Bus Analysis Finds Fuel Economy to be 1.4 Times Higher than

Science.gov Websites

Diesel | News | NREL Fuel Cell Bus Analysis Finds Fuel Economy to be 1.4 Times Higher than Diesel NREL Fuel Cell Bus Analysis Finds Fuel Economy to be 1.4 Times Higher than Diesel December 2, 2016 NREL has published a new report showing that the average fuel economy of fuel cell electric buses from

Water reactive hydrogen fuel cell power system

DOEpatents

Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

2014-01-21

A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

Water reactive hydrogen fuel cell power system

DOEpatents

Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

2014-11-25

A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into the fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

Connections for solid oxide fuel cells

DOEpatents

Collie, Jeffrey C.

1999-01-01

A connection for fuel cell assemblies is disclosed. The connection includes compliant members connected to individual fuel cells and a rigid member connected to the compliant members. Adjacent bundles or modules of fuel cells are connected together by mechanically joining their rigid members. The compliant/rigid connection permits construction of generator fuel cell stacks from basic modular groups of cells of any desired size. The connections can be made prior to installation of the fuel cells in a generator, thereby eliminating the need for in-situ completion of the connections. In addition to allowing pre-fabrication, the compliant/rigid connections also simplify removal and replacement of sections of a generator fuel cell stack.

The fuel cell in space: Yesterday, today and tomorrow

NASA Technical Reports Server (NTRS)

Warshay, Marvin; Prokopius, Paul R.

1989-01-01

The past, present, and future of space fuel cell power systems is reviewed, starting with the first practical fuel cell by F.T. Bacon which led to the 1.5 kW Apollo alkaline fuel cell. However, the first fuel cell to be used for space power was the Gemini 1.0 kW Acid IEM fuel cell. The successor to the Apollo fuel cell is today's 12 kW Orbiter alkaline fuel cell whose technology is considerably different and considerably better than that of its ancestor, the Bacon cell. And in terms of specific weight there has been a steady improvement from the past to the present, from the close to 200 lb/kW of Apollo to the 20 lb/kW of the orbiter. For NASA future Lunar and Martian surface power requirements the regenerative fuel cell (RFC) energy storage system is enabling technology, with the alkaline and the PEM the leading RFC candidate systems. The U.S. Air Force continues to support fuel cell high power density technology development for its future short duration applications.

Impacts | Hydrogen and Fuel Cells | NREL

Science.gov Websites

Impacts Impacts Read about NREL's impacts on innovations in hydrogen and fuel cell research and -Splitting Electrodes NREL Shows How Cyanobacteria Build Hydrogen-Producing Enzyme Fuel Cell Systems R&D -Speed Scanner to Monitor Fuel Cell Material Defects Making Fuel Cells Cleaner, Better, and Cheaper GM

49 CFR 173.230 - Fuel cell cartridges containing hazardous material.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Fuel cell cartridges containing hazardous material... Than Class 1 and Class 7 § 173.230 Fuel cell cartridges containing hazardous material. (a) Requirements for Fuel Cell Cartridges. Fuel cell cartridges, including when contained in or packed with equipment...

Economics of Direct Hydrogen Polymer Electrolyte Membrane Fuel Cell Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahadevan, Kathyayani

Battelle's Economic Analysis of PEM Fuel Cell Systems project was initiated in 2003 to evaluate the technology and markets that are near-term and potentially could support the transition to fuel cells in automotive markets. The objective of Battelle?s project was to assist the DOE in developing fuel cell systems for pre-automotive applications by analyzing the technical, economic, and market drivers of direct hydrogen PEM fuel cell adoption. The project was executed over a 6-year period (2003 to 2010) and a variety of analyses were completed in that period. The analyses presented in the final report include: Commercialization scenarios for stationarymore » generation through 2015 (2004); Stakeholder feedback on technology status and performance status of fuel cell systems (2004); Development of manufacturing costs of stationary PEM fuel cell systems for backup power markets (2004); Identification of near-term and mid-term markets for PEM fuel cells (2006); Development of the value proposition and market opportunity of PEM fuel cells in near-term markets by assessing the lifecycle cost of PEM fuel cells as compared to conventional alternatives used in the marketplace and modeling market penetration (2006); Development of the value proposition of PEM fuel cells in government markets (2007); Development of the value proposition and opportunity for large fuel cell system application at data centers and wastewater treatment plants (2008); Update of the manufacturing costs of PEM fuel cells for backup power applications (2009).« less

Novel carbon-ion fuel cells. Quarterly technical report No. 10, January 1, 1996--March 31, 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cocks, F.H.

1996-08-01

This report presents research to develop an entirely new, fundamentally different class of fuel cell using a solid electrolyte that transports carbon ions. This fuel cell would use solid carbon dissolved in molten metal as a fuel reservoir and anode; expensive gaseous or liquid fuel would not be required. A high temperature fuel cell based on a carbon ion membrane/electrolyte would operate in a way like yttria-doped zirconia solid oxide fuel cells; however, the fuel cell would transport the C ion from a fuel source to O{sub 2} in the atmosphere. Such fuel cells, operating above 1000 C, would producemore » an exhaust gas that could be fed directly into existing boilers, and could thus act as ``topping cycles`` to existing power plant steam cycles.« less

Ambient pressure fuel cell system

DOEpatents

Wilson, Mahlon S.

2000-01-01

An ambient pressure fuel cell system is provided with a fuel cell stack formed from a plurality of fuel cells having membrane/electrode assemblies (MEAs) that are hydrated with liquid water and bipolar plates with anode and cathode sides for distributing hydrogen fuel gas and water to a first side of each one of the MEAs and air with reactant oxygen gas to a second side of each one of the MEAs. A pump supplies liquid water to the fuel cells. A recirculating system may be used to return unused hydrogen fuel gas to the stack. A near-ambient pressure blower blows air through the fuel cell stack in excess of reaction stoichiometric amounts to react with the hydrogen fuel gas.

Enhanced methanol utilization in direct methanol fuel cell

DOEpatents

Ren, Xiaoming; Gottesfeld, Shimshon

2001-10-02

The fuel utilization of a direct methanol fuel cell is enhanced for improved cell efficiency. Distribution plates at the anode and cathode of the fuel cell are configured to distribute reactants vertically and laterally uniformly over a catalyzed membrane surface of the fuel cell. A conductive sheet between the anode distribution plate and the anodic membrane surface forms a mass transport barrier to the methanol fuel that is large relative to a mass transport barrier for a gaseous hydrogen fuel cell. In a preferred embodiment, the distribution plate is a perforated corrugated sheet. The mass transport barrier may be conveniently increased by increasing the thickness of an anode conductive sheet adjacent the membrane surface of the fuel cell.

Inorganic salt mixtures as electrolyte media in fuel cells

NASA Technical Reports Server (NTRS)

Angell, Charles Austen (Inventor); Francis-Gervasio, Dominic (Inventor); Belieres, Jean-Philippe (Inventor)

2012-01-01

Fuel cell designs and techniques for converting chemical energy into electrical energy uses a fuel cell are disclosed. The designs and techniques include an anode to receive fuel, a cathode to receive oxygen, and an electrolyte chamber in the fuel cell, including an electrolyte medium, where the electrolyte medium includes an inorganic salt mixture in the fuel cell. The salt mixture includes pre-determined quantities of at least two salts chosen from a group consisting of ammonium trifluoromethanesulfonate, ammonium trifluoroacetate, and ammonium nitrate, to conduct charge from the anode to the cathode. The fuel cell includes an electrical circuit operatively coupled to the fuel cell to transport electrons from the cathode.

Direct methanol feed fuel cell and system

NASA Technical Reports Server (NTRS)

Surampudi, Subbarao (Inventor); Kindler, Andrew (Inventor); Halpert, Gerald (Inventor); Frank, Harvey A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Jeffries-Nakamura, Barbara (Inventor)

2009-01-01

Improvements to non acid methanol fuel cells include new formulations for materials. The platinum and ruthenium are more exactly mixed together. Different materials are substituted for these materials. The backing material for the fuel cell electrode is specially treated to improve its characteristics. A special sputtered electrode is formed which is extremely porous. The fuel cell system also comprises a fuel supplying part including a meter which meters an amount of fuel which is used by the fuel cell, and controls the supply of fuel based on said metering.

Fuel cell generator energy dissipator

DOEpatents

Veyo, Stephen Emery; Dederer, Jeffrey Todd; Gordon, John Thomas; Shockling, Larry Anthony

2000-01-01

An apparatus and method are disclosed for eliminating the chemical energy of fuel remaining in a fuel cell generator when the electrical power output of the fuel cell generator is terminated. During a generator shut down condition, electrically resistive elements are automatically connected across the fuel cell generator terminals in order to draw current, thereby depleting the fuel

Active Polar Gels: a Paradigm for Cytoskeletal Dynamics

NASA Astrophysics Data System (ADS)

Julicher, Frank

2006-03-01

The cytoskeleton of eucaryotic cells is an intrinsically dynamic network of rod-like filaments. Active processes on the molecular scale such as the action of motor proteins and the polymerization and depolymerization of filaments drive active dynamic behaviors while consuming chemical energy in the form of a fuel. Such emergent dynamics is regulated by the cell and is important for many cellular processes such as cell locomotion and cell division. From a general point of view the cytoskeleton represents an active gel-like material with interesting material properties. We present a general theory of active viscoelastic materials made of polar filaments which is motivated by the the cytoskeleton. The continuous consumption of a fuel generates a non- equilibrium state characterized by the generation of flows and stresses. Our theory can be applied to experiments in which cytoskeletal patterns are set in motion by active processes such as those which are at work in cells. It can also capture generic aspects of the flows and stress profiles which occur during cell locomotion.

Fuel processors for fuel cell APU applications

NASA Astrophysics Data System (ADS)

Aicher, T.; Lenz, B.; Gschnell, F.; Groos, U.; Federici, F.; Caprile, L.; Parodi, L.

The conversion of liquid hydrocarbons to a hydrogen rich product gas is a central process step in fuel processors for auxiliary power units (APUs) for vehicles of all kinds. The selection of the reforming process depends on the fuel and the type of the fuel cell. For vehicle power trains, liquid hydrocarbons like gasoline, kerosene, and diesel are utilized and, therefore, they will also be the fuel for the respective APU systems. The fuel cells commonly envisioned for mobile APU applications are molten carbonate fuel cells (MCFC), solid oxide fuel cells (SOFC), and proton exchange membrane fuel cells (PEMFC). Since high-temperature fuel cells, e.g. MCFCs or SOFCs, can be supplied with a feed gas that contains carbon monoxide (CO) their fuel processor does not require reactors for CO reduction and removal. For PEMFCs on the other hand, CO concentrations in the feed gas must not exceed 50 ppm, better 20 ppm, which requires additional reactors downstream of the reforming reactor. This paper gives an overview of the current state of the fuel processor development for APU applications and APU system developments. Furthermore, it will present the latest developments at Fraunhofer ISE regarding fuel processors for high-temperature fuel cell APU systems on board of ships and aircrafts.

1990 fuel cell seminar: Program and abstracts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1990-12-31

This volume contains author prepared short resumes of the presentations at the 1990 Fuel Cell Seminar held November 25-28, 1990 in Phoenix, Arizona. Contained herein are 134 short descriptions organized into topic areas entitled An Environmental Overview, Transportation Applications, Technology Advancements for Molten Carbonate Fuel Cells, Technology Advancements for Solid Fuel Cells, Component Technologies and Systems Analysis, Stationary Power Applications, Marine and Space Applications, Technology Advancements for Acid Type Fuel Cells, and Technology Advancement for Solid Oxide Fuel Cells.

Castellated structures for ITER: Differences of impurity deposition and fuel accumulation in the toroidal and poloidal gaps

NASA Astrophysics Data System (ADS)

Litnovsky, A.; Philipps, V.; Wienhold, P.; Krieger, K.; Kirschner, A.; Borodin, D.; Sergienko, G.; Schmitz, O.; Kreter, A.; Samm, U.; Richter, S.; Breuer, U.; Textor Team

2009-04-01

Castellation is foreseen for the first wall and divertor area in ITER. The concern of the fuel accumulation and impurity deposition in the gaps of castellated structures calls for dedicated studies. Recently, a tungsten castellated limiter with rectangular and roof-like shaped cells was exposed to the SOL plasmas in TEXTOR. After exposure, roughly two times less fuel was found in the gaps between the shaped cells whereas the difference in carbon deposition was less pronounced. Up to 70 at.% of tungsten was found intermixed in the deposited layers in the gaps. The metal fraction in the deposit decreases rapidly with a depth of the gap. Modeling of carbon deposition in poloidal gaps has provided a qualitative agreement with an experiment. The significant anisotropy of C and D distributions in the toroidal gaps was measured.

Use of multi-functional flexible micro-sensors for in situ measurement of temperature, voltage and fuel flow in a proton exchange membrane fuel cell.

PubMed

Lee, Chi-Yuan; Chan, Pin-Cheng; Lee, Chung-Ju

2010-01-01

Temperature, voltage and fuel flow distribution all contribute considerably to fuel cell performance. Conventional methods cannot accurately determine parameter changes inside a fuel cell. This investigation developed flexible and multi-functional micro sensors on a 40 μm-thick stainless steel foil substrate by using micro-electro-mechanical systems (MEMS) and embedded them in a proton exchange membrane fuel cell (PEMFC) to measure the temperature, voltage and flow. Users can monitor and control in situ the temperature, voltage and fuel flow distribution in the cell. Thereby, both fuel cell performance and lifetime can be increased.

U.S. Department of Energy-Funded Performance Validation of Fuel Cell Material Handling Equipment (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, J.; Sprik, S.; Ramsden, T.

2013-11-01

This webinar presentation to the UK Hydrogen and Fuel Cell Association summarizes how the U.S. Department of Energy is enabling early fuel cell markets; describes objectives of the National Fuel Cell Technology Evaluation Center; and presents performance status of fuel cell material handling equipment.

Fuel Cell Electric Vehicle Evaluations | Hydrogen and Fuel Cells | NREL

Science.gov Websites

Electric Vehicle Evaluations Fuel Cell Electric Vehicle Evaluations NREL's technology validation include commercial FCEVs for the first time. Current fuel cell electric vehicle evaluations build on the seven-year FCEV Learning Demonstration and focus on fuel cell stack durability and efficiency, vehicle

14 CFR 31.45 - Fuel cells.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel cells. 31.45 Section 31.45 Aeronautics... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.45 Fuel cells. If fuel cells are used, the fuel cells, their attachments, and related supporting structure must be shown by tests to be capable of...

14 CFR 31.45 - Fuel cells.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Fuel cells. 31.45 Section 31.45 Aeronautics... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.45 Fuel cells. If fuel cells are used, the fuel cells, their attachments, and related supporting structure must be shown by tests to be capable of...

14 CFR 31.45 - Fuel cells.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Fuel cells. 31.45 Section 31.45 Aeronautics... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.45 Fuel cells. If fuel cells are used, the fuel cells, their attachments, and related supporting structure must be shown by tests to be capable of...

14 CFR 31.45 - Fuel cells.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Fuel cells. 31.45 Section 31.45 Aeronautics... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.45 Fuel cells. If fuel cells are used, the fuel cells, their attachments, and related supporting structure must be shown by tests to be capable of...

14 CFR 31.45 - Fuel cells.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Fuel cells. 31.45 Section 31.45 Aeronautics... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.45 Fuel cells. If fuel cells are used, the fuel cells, their attachments, and related supporting structure must be shown by tests to be capable of...

An operationally flexible fuel cell based on quaternary ammonium-biphosphate ion pairs

DOE PAGES

Lee, Kwan -Soo; Spendelow, Jacob Schatz; Choe, Yoong -Kee; ...

2016-08-22

Here, fuel cells are promising devices for clean power generation in a variety of economically and environmentally significant applications. Low-temperature proton exchange membrane (PEM) fuel cells utilizing Nafion require a high level of hydration, which limits the operating temperature to less than 100°C. In contrast, high-temperature PEM fuel cells utilizing phosphoric acid-doped polybenzimidazole can operate effectively up to 180°C; however, these devices degrade when exposed to water below 140°C. Here we present a different class of PEM fuel cells based on quaternary ammonium-biphosphate ion pairs that can operate under conditions unattainable with existing fuel cell technologies. These fuel cells exhibitmore » stable performance at 80–160°C with a conductivity decay rate more than three orders of magnitude lower than that of a commercial high-temperature PEM fuel cell. By increasing the operational flexibility, this class of fuel cell can simplify the requirements for heat and water management, and potentially reduce the costs associated with the existing fully functional fuel cell systems.« less

An operationally flexible fuel cell based on quaternary ammonium-biphosphate ion pairs

NASA Astrophysics Data System (ADS)

Lee, Kwan-Soo; Spendelow, Jacob S.; Choe, Yoong-Kee; Fujimoto, Cy; Kim, Yu Seung

2016-09-01

Fuel cells are promising devices for clean power generation in a variety of economically and environmentally significant applications. Low-temperature proton exchange membrane (PEM) fuel cells utilizing Nafion require a high level of hydration, which limits the operating temperature to less than 100 ∘C. In contrast, high-temperature PEM fuel cells utilizing phosphoric acid-doped polybenzimidazole can operate effectively up to 180 ∘C however, these devices degrade when exposed to water below 140 ∘C. Here we present a different class of PEM fuel cells based on quaternary ammonium-biphosphate ion pairs that can operate under conditions unattainable with existing fuel cell technologies. These fuel cells exhibit stable performance at 80-160 ∘C with a conductivity decay rate more than three orders of magnitude lower than that of a commercial high-temperature PEM fuel cell. By increasing the operational flexibility, this class of fuel cell can simplify the requirements for heat and water management, and potentially reduce the costs associated with the existing fully functional fuel cell systems.

Fuel cell stack monitoring and system control

DOEpatents

Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

2005-01-25

A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell. Other polarization curves may be generated and used for fuel cell stack monitoring based on different operating pressures, temperatures, hydrogen quantities.

Effective sulfur and energy recovery from hydrogen sulfide through incorporating an air-cathode fuel cell into chelated-iron process.

PubMed

Sun, Min; Song, Wei; Zhai, Lin-Feng; Cui, Yu-Zhi

2013-12-15

The chelated-iron process is among the most promising techniques for the hydrogen sulfide (H2S) removal due to its double advantage of waste minimization and resource recovery. However, this technology has encountered the problem of chelate degradation which made it difficult to ensure reliable and economical operation. This work aims to develop a novel fuel-cell-assisted chelated-iron process which employs an air-cathode fuel cell for the catalyst regeneration. By using such a process, sulfur and electricity were effectively recovered from H2S and the problem of chelate degradation was well controlled. Experiment on a synthetic sulfide solution showed the fuel-cell-assisted chelated-iron process could maintain high sulfur recovery efficiencies generally above 90.0%. The EDTA was preferable to NTA as the chelating agent for electricity generation, given the Coulombic efficiencies (CEs) of 17.8 ± 0.5% to 75.1 ± 0.5% for the EDTA-chelated process versus 9.6 ± 0.8% to 51.1 ± 2.7% for the NTA-chelated process in the pH range of 4.0-10.0. The Fe (III)/S(2-) ratio exhibited notable influence on the electricity generation, with the CEs improved by more than 25% as the Fe (III)/S(2-) molar ratio increased from 2.5:1 to 3.5:1. Application of this novel process in treating a H2S-containing biogas stream achieved 99% of H2S removal efficiency, 78% of sulfur recovery efficiency, and 78.6% of energy recovery efficiency, suggesting the fuel-cell-assisted chelated-iron process was effective to remove the H2S from gas streams with favorable sulfur and energy recovery efficiencies. Copyright © 2013 Elsevier B.V. All rights reserved.

Fuel Exhaling Fuel Cell.

PubMed

Manzoor Bhat, Zahid; Thimmappa, Ravikumar; Devendrachari, Mruthyunjayachari Chattanahalli; Kottaichamy, Alagar Raja; Shafi, Shahid Pottachola; Varhade, Swapnil; Gautam, Manu; Thotiyl, Musthafa Ottakam

2018-01-18

State-of-the-art proton exchange membrane fuel cells (PEMFCs) anodically inhale H 2 fuel and cathodically expel water molecules. We show an unprecedented fuel cell concept exhibiting cathodic fuel exhalation capability of anodically inhaled fuel, driven by the neutralization energy on decoupling the direct acid-base chemistry. The fuel exhaling fuel cell delivered a peak power density of 70 mW/cm 2 at a peak current density of 160 mA/cm 2 with a cathodic H 2 output of ∼80 mL in 1 h. We illustrate that the energy benefits from the same fuel stream can at least be doubled by directing it through proposed neutralization electrochemical cell prior to PEMFC in a tandem configuration.

Sodium Borohydride/Hydrogen Peroxide Fuel Cells For Space Application

NASA Technical Reports Server (NTRS)

Valdez, T. I.; Deelo, M. E.; Narayanan, S. R.

2006-01-01

This viewgraph presentation examines Sodium Borohydride and Hydrogen Peroxide Fuel Cells as they are applied to space applications. The topics include: 1) Motivation; 2) The Sodium Borohydride Fuel Cell; 3) Sodium Borohydride Fuel Cell Test Stands; 4) Fuel Cell Comparisons; 5) MEA Performance; 6) Anode Polarization; and 7) Electrode Analysis. The benefits of hydrogen peroxide as an oxidant and benefits of sodium borohydride as a fuel are also addressed.

Fuel cell stack monitoring and system control

DOEpatents

Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

2004-02-17

A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell.

Multi-fuel reformers for fuel cells used in transportation. Phase 1: Multi-fuel reformers

NASA Astrophysics Data System (ADS)

1994-05-01

DOE has established the goal, through the Fuel Cells in Transportation Program, of fostering the rapid development and commercialization of fuel cells as economic competitors for the internal combustion engine. Central to this goal is a safe feasible means of supplying hydrogen of the required purity to the vehicular fuel cell system. Two basic strategies are being considered: (1) on-board fuel processing whereby alternative fuels such as methanol, ethanol or natural gas stored on the vehicle undergo reformation and subsequent processing to produce hydrogen, and (2) on-board storage of pure hydrogen provided by stationary fuel processing plants. This report analyzes fuel processor technologies, types of fuel and fuel cell options for on-board reformation. As the Phase 1 of a multi-phased program to develop a prototype multi-fuel reformer system for a fuel cell powered vehicle, the objective of this program was to evaluate the feasibility of a multi-fuel reformer concept and to select a reforming technology for further development in the Phase 2 program, with the ultimate goal of integration with a DOE-designated fuel cell and vehicle configuration. The basic reformer processes examined in this study included catalytic steam reforming (SR), non-catalytic partial oxidation (POX) and catalytic partial oxidation (also known as Autothermal Reforming, or ATR). Fuels under consideration in this study included methanol, ethanol, and natural gas. A systematic evaluation of reforming technologies, fuels, and transportation fuel cell applications was conducted for the purpose of selecting a suitable multi-fuel processor for further development and demonstration in a transportation application.

Carbon deposition thresholds on nickel-based solid oxide fuel cell anodes II. Steam:carbon ratio and current density

NASA Astrophysics Data System (ADS)

Kuhn, J.; Kesler, O.

2015-03-01

For the second part of a two part publication, coking thresholds with respect to molar steam:carbon ratio (SC) and current density in nickel-based solid oxide fuel cells were determined. Anode-supported button cell samples were exposed to 2-component and 5-component gas mixtures with 1 ≤ SC ≤ 2 and zero fuel utilization for 10 h, followed by measurement of the resulting carbon mass. The effect of current density was explored by measuring carbon mass under conditions known to be prone to coking while increasing the current density until the cell was carbon-free. The SC coking thresholds were measured to be ∼1.04 and ∼1.18 at 600 and 700 °C, respectively. Current density experiments validated the thresholds measured with respect to fuel utilization and steam:carbon ratio. Coking thresholds at 600 °C could be predicted with thermodynamic equilibrium calculations when the Gibbs free energy of carbon was appropriately modified. Here, the Gibbs free energy of carbon on nickel-based anode support cermets was measured to be -6.91 ± 0.08 kJ mol-1. The results of this two part publication show that thermodynamic equilibrium calculations with appropriate modification to the Gibbs free energy of solid-phase carbon can be used to predict coking thresholds on nickel-based anodes at 600-700 °C.

Thermally regenerative hydrogen/oxygen fuel cell power cycles

NASA Technical Reports Server (NTRS)

Morehouse, J. H.

1986-01-01

Two innovative thermodynamic power cycles are analytically examined for future engineering feasibility. The power cycles use a hydrogen-oxygen fuel cell for electrical energy production and use the thermal dissociation of water for regeneration of the hydrogen and oxygen. The TDS (thermal dissociation system) uses a thermal energy input at over 2000 K to thermally dissociate the water. The other cycle, the HTE (high temperature electrolyzer) system, dissociates the water using an electrolyzer operating at high temperature (1300 K) which receives its electrical energy from the fuel cell. The primary advantages of these cycles is that they are basically a no moving parts system, thus having the potential for long life and high reliability, and they have the potential for high thermal efficiency. Both cycles are shown to be classical heat engines with ideal efficiency close to Carnot cycle efficiency. The feasibility of constructing actual cycles is investigated by examining process irreversibilities and device efficiencies for the two types of cycles. The results show that while the processes and devices of the 2000 K TDS exceed current technology limits, the high temperature electrolyzer system appears to be a state-of-the-art technology development. The requirements for very high electrolyzer and fuel cell efficiencies are seen as determining the feasbility of the HTE system, and these high efficiency devices are currently being developed. It is concluded that a proof-of-concept HTE system experiment can and should be conducted.

Nondestructive cell evaluation techniques in SOFC stack manufacturing

NASA Astrophysics Data System (ADS)

Wunderlich, C.

2016-04-01

Independent from the specifics of the application, a cost efficient manufacturing of solid oxide fuel cells (SOFC), its electrolyte membranes and other stack components, leading to reliable long-life stacks is the key for the commercial viability of this fuel cell technology. Tensile and shear stresses are most critical for ceramic components and especially for thin electrolyte membranes as used in SOFC cells. Although stack developers try to reduce tensile stresses acting on the electrolyte by either matching CTE of interconnects and electrolytes or by putting SOFC cells under some pressure - at least during transient operation of SOFC stacks ceramic cells will experience some tensile stresses. Electrolytes are required to have a high Weibull characteristic fracture strength. Practical experiences in stack manufacturing have shown that statistical fracture strength data generated by tests of electrolyte samples give limited information on electrolyte or cell quality. In addition, the cutting process of SOFC electrolytes has a major influence on crack initiation. Typically, any single crack in one the 30 to 80 cells in series connection will lead to a premature stack failure drastically reducing stack service life. Thus, for statistical reasons only 100% defect free SOFC cells must be assembled in stacks. This underlines the need for an automated inspection. So far, only manual processes of visual or mechanical electrolyte inspection are established. Fraunhofer IKTS has qualified the method of optical coherence tomography for an automated high throughput inspection. Alternatives like laser speckle photometry and acoustical methods are still under investigation.

Fuels processing for transportation fuel cell systems

NASA Astrophysics Data System (ADS)

Kumar, R.; Ahmed, S.

Fuel cells primarily use hydrogen as the fuel. This hydrogen must be produced from other fuels such as natural gas or methanol. The fuel processor requirements are affected by the fuel to be converted, the type of fuel cell to be supplied, and the fuel cell application. The conventional fuel processing technology has been reexamined to determine how it must be adapted for use in demanding applications such as transportation. The two major fuel conversion processes are steam reforming and partial oxidation reforming. The former is established practice for stationary applications; the latter offers certain advantages for mobile systems and is presently in various stages of development. This paper discusses these fuel processing technologies and the more recent developments for fuel cell systems used in transportation. The need for new materials in fuels processing, particularly in the area of reforming catalysis and hydrogen purification, is discussed.

Preparation of Carbon-Platinum-Ceria and Carbon-Platinum-Cerium catalysts and its application in Polymer Electrolyte Fuel Cell: Hydrogen, Methanol, and Ethanol

NASA Astrophysics Data System (ADS)

Guzman Blas, Rolando Pedro

This thesis is focused on fuel cells using hydrogen, methanol and ethanol as fuel. Also, in the method of preparation of catalytic material for the anode: Supercritical Fluid Deposition (SFD) and impregnation method using ethylenediaminetetraacetic acid (EDTA) as a chelating agent. The first part of the thesis describes the general knowledge about Hydrogen Polymer Exchange Membrane Fuel Cell (HPEMFC),Direct Methanol Fuel Cell (DMFC) and Direct Ethanol Fuel Cell (DEFC), as well as the properties of Cerium and CeO2 (Ceria). The second part of the thesis describes the preparation of catalytic material by Supercritical Fluid Deposition (SFD). SFD was utilized to deposit Pt and ceria simultaneously onto gas diffusion layers. The Pt-ceria catalyst deposited by SFD exhibited higher methanol oxidation activity compared to the platinum catalyst alone. The linear sweep traces of the cathode made for the methanol cross over study indicate that Pt-Ceria/C as the anode catalyst, due to its better activity for methanol, improves the fuel utilization, minimizing the methanol permeation from anode to cathode compartment. The third and fourth parts of the thesis describe the preparation of material catalytic material Carbon-Platinum-Cerium by a simple and cheap impregnation method using EDTA as a chelating agent to form a complex with cerium (III). This preparation method allows the mass production of the material catalysts without additional significant cost. Fuel cell polarization and power curves experiments showed that the Carbon-Platinum-Cerium anode materials exhibited better catalytic activity than the only Vulcan-Pt catalysts for DMFC, DEFC and HPEMFC. In the case of Vulcan-20%Pt-5%w Cerium, this material exhibits better catalytic activity than the Vulcan-20%Pt in DMFC. In the case of Vulcan-40% Pt-doped Cerium, this material exhibits better catalytic activity than the Vulcan-40% Pt in DMFC, DEFC and HPEMFC. Finally, I propose a theory that explains the reason why the carbon-platinum-cerium has better catalytic activity than platinum-carbon. Due to the hybridization behavior of C and Ce could arise charge transfer, both carbon and cerium to the Platinum. Ce-C→Pt charge transfer could occur at the Ce-C/Pt interface. Thus, results in an increase in the catalytic activity of platinum-cerium-carbon when compared with carbon-platinum.

Analysis, operation and maintenance of a fuel cell/battery series-hybrid bus for urban transit applications

NASA Astrophysics Data System (ADS)

Bubna, Piyush; Brunner, Doug; Gangloff, John J.; Advani, Suresh G.; Prasad, Ajay K.

The fuel cell hybrid bus (FCHB) program was initiated at the University of Delaware in 2005 to demonstrate the viability of fuel cell vehicles for transit applications and to conduct research and development to facilitate the path towards their eventual commercialization. Unlike other fuel cell bus programs, the University of Delaware's FCHB design features a battery-heavy hybrid which offers multiple advantages in terms of cost, performance and durability. The current fuel cell hybrid bus is driven on a regular transit route at the University of Delaware. The paper describes the baseline specifications of the bus with a focus on the fuel cell and the balance of plant. The fuel cell/battery series-hybrid design is well suited for urban transit routes and provides key operational advantages such as hydrogen fuel economy, efficient use of the fuel cell for battery recharging, and regenerative braking. The bus is equipped with a variety of sensors including a custom-designed cell voltage monitoring system which provide a good understanding of bus performance under normal operation. Real-time data collection and analysis have yielded key insights for fuel cell bus design optimization. Results presented here illustrate the complex flow of energy within the various subsystems of the fuel cell hybrid bus. A description of maintenance events has been included to highlight the issues that arise during general operation. The paper also describes several modifications that will facilitate design improvements in future versions of the bus. Overall, the fuel cell hybrid bus demonstrates the viability of fuel cells for urban transit applications in real world conditions.

Low contaminant formic acid fuel for direct liquid fuel cell

DOEpatents

Masel, Richard I [Champaign, IL; Zhu, Yimin [Urbana, IL; Kahn, Zakia [Palatine, IL; Man, Malcolm [Vancouver, CA

2009-11-17

A low contaminant formic acid fuel is especially suited toward use in a direct organic liquid fuel cell. A fuel of the invention provides high power output that is maintained for a substantial time and the fuel is substantially non-flammable. Specific contaminants and contaminant levels have been identified as being deleterious to the performance of a formic acid fuel in a fuel cell, and embodiments of the invention provide low contaminant fuels that have improved performance compared to known commercial bulk grade and commercial purified grade formic acid fuels. Preferred embodiment fuels (and fuel cells containing such fuels) including low levels of a combination of key contaminants, including acetic acid, methyl formate, and methanol.

Evolution of Gas Cell Targets for Magnetized Liner Inertial Fusion Experiments at the Sandia National Laboratories PECOS Test Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paguio, R. R.; Smith, G. E.; Taylor, J. L.

Z-Beamlet (ZBL) experiments conducted at the PECOS test facility at Sandia National Laboratories (SNL) investigated the nonlinear processes in laser plasma interaction (or laserplasma instabilities LPI) that complicate the deposition of laser energy by enhanced absorption, backscatter, filamentation and beam-spray that can occur in large-scale laser-heated gas cell targets. These targets and experiments were designed to provide better insight into the physics of the laser preheat stage of the Magnetized Liner Inertial Fusion (MagLIF) scheme being tested on the SNL Z-machine. The experiments aim to understand the tradeoffs between laser spot size, laser pulse shape, laser entrance hole (LEH) windowmore » thickness, and fuel density for laser preheat. Gas cell target design evolution and fabrication adaptations to accommodate the evolving experiment and scientific requirements are also described in this paper.« less

Evolution of Gas Cell Targets for Magnetized Liner Inertial Fusion Experiments at the Sandia National Laboratories PECOS Test Facility

DOE PAGES

Paguio, R. R.; Smith, G. E.; Taylor, J. L.; ...

2017-12-04

Z-Beamlet (ZBL) experiments conducted at the PECOS test facility at Sandia National Laboratories (SNL) investigated the nonlinear processes in laser plasma interaction (or laserplasma instabilities LPI) that complicate the deposition of laser energy by enhanced absorption, backscatter, filamentation and beam-spray that can occur in large-scale laser-heated gas cell targets. These targets and experiments were designed to provide better insight into the physics of the laser preheat stage of the Magnetized Liner Inertial Fusion (MagLIF) scheme being tested on the SNL Z-machine. The experiments aim to understand the tradeoffs between laser spot size, laser pulse shape, laser entrance hole (LEH) windowmore » thickness, and fuel density for laser preheat. Gas cell target design evolution and fabrication adaptations to accommodate the evolving experiment and scientific requirements are also described in this paper.« less

Fuel cells for vehicle applications in cars - bringing the future closer

NASA Astrophysics Data System (ADS)

Panik, Ferdinand

Among all alternative drive systems, the fuel cell electric propulsion system has the highest potential to compete with the internal combustion engine. For this reason, Daimler-Benz AG has entered into a co-operative alliance with Ballard Power Systems, with the objectives of bringing fuel cell vehicles to the market. Apart from the fuel cell itself, fuel cell vehicles require comprehensive system technology to provide fuel and air supply, cooling, energy management, electric and electronic functions. The system technology determines to a large extent the cost, weight, efficiency, performance and overall customer benefit of fuel cell vehicles. Hence, Daimler-Benz and Ballard are pooling their expertise in fuel cell system technology in a joint company, with the aim of bringing their fuel cell vehicular systems to the stage of maturity required for market entry as early as possible. Hydrogen-fuelled zero-emission fuel cell transit `buses' will be the first market segment addressed, with an emphasis on the North American and European markets. The first buses are already scheduled for delivery to customers in late 1997. Since a liquid fuel like methanol is easier to handle in passenger cars, fuel reforming technologies are developed and will shortly be demonstrated in a prototype, as well. The presentation will cover concepts of fuel cell vehicles with an emphasis on system technology, the related testing procedures and results as well as an outline of market entry strategies.

Hybrid fuel cell/diesel generation total energy system, part 2

NASA Astrophysics Data System (ADS)

Blazek, C. F.

1982-11-01

Meeting the Goldstone Deep Space Communications Complex (DGSCC) electrical and thermal requirements with the existing system was compared with using fuel cells. Fuel cell technology selection was based on a 1985 time frame for installation. The most cost-effective fuel feedstock for fuel cell application was identified. Fuels considered included diesel oil, natural gas, methanol and coal. These fuel feedstocks were considered not only on the cost and efficiency of the fuel conversion process, but also on complexity and integration of the fuel processor on system operation and thermal energy availability. After a review of fuel processor technology, catalytic steam reformer technology was selected based on the ease of integration and the economics of hydrogen production. The phosphoric acid fuel cell was selected for application at the GDSCC due to its commercial readiness for near term application. Fuel cell systems were analyzed for both natural gas and methanol feedstock. The subsequent economic analysis indicated that a natural gas fueled system was the most cost effective of the cases analyzed.

Hybrid fuel cell/diesel generation total energy system, part 2

NASA Technical Reports Server (NTRS)

Blazek, C. F.

1982-01-01

Meeting the Goldstone Deep Space Communications Complex (DGSCC) electrical and thermal requirements with the existing system was compared with using fuel cells. Fuel cell technology selection was based on a 1985 time frame for installation. The most cost-effective fuel feedstock for fuel cell application was identified. Fuels considered included diesel oil, natural gas, methanol and coal. These fuel feedstocks were considered not only on the cost and efficiency of the fuel conversion process, but also on complexity and integration of the fuel processor on system operation and thermal energy availability. After a review of fuel processor technology, catalytic steam reformer technology was selected based on the ease of integration and the economics of hydrogen production. The phosphoric acid fuel cell was selected for application at the GDSCC due to its commercial readiness for near term application. Fuel cell systems were analyzed for both natural gas and methanol feedstock. The subsequent economic analysis indicated that a natural gas fueled system was the most cost effective of the cases analyzed.

Titanium dioxide in fuel cell technology: An overview

NASA Astrophysics Data System (ADS)

Abdullah, N.; Kamarudin, S. K.

2015-03-01

Fuel cell technology is one of the alternative energy sources for the next generation. Although this technology has proven to be one of the main methods for producing new energy sources, fuel cell technology still has some problems that hinder fuel cell commercialization. Recently, new ideas on titanium dioxide are introduced as potential solution in several applications in fuel cell technology. Thus, this article presents an overview on the applications of titanium dioxide and highlights the unique properties and benefits of titanium dioxide in fuel cell technology.

Thin Film Catalyst Layers for Direct Methanol Fuel Cells

NASA Technical Reports Server (NTRS)

Witham, C. K.; Chun, W.; Ruiz, R.; Valdez, T. I.; Narayanan, S. R.

2000-01-01

One of the primary obstacles to the widespread use of the direct methanol fuel cell (DMFC) is the high cost of the catalyst. Therefore, reducing the catalyst loading well below the current level of 8-12 mg/cm 2 would be important to commercialization. The current methods for preparation of catalyst layers consisting of catalyst, ionomer and sometimes a hydrophobic additive are applied by either painting, spraying, decal transfer or screen printing processes. Sputter deposition is a coating technique widely used in manufacturing and therefore particularly attractive. In this study we have begun to explore sputtering as a method for catalyst deposition. Present experiments focus on Pt-Ru catalyst layers for the anode.

Organic fuel cells and fuel cell conducting sheets

DOEpatents

Masel, Richard I.; Ha, Su; Adams, Brian

2007-10-16

A passive direct organic fuel cell includes an organic fuel solution and is operative to produce at least 15 mW/cm.sup.2 when operating at room temperature. In additional aspects of the invention, fuel cells can include a gas remover configured to promote circulation of an organic fuel solution when gas passes through the solution, a modified carbon cloth, one or more sealants, and a replaceable fuel cartridge.

Fuzzy control based engine sizing optimization for a fuel cell/battery hybrid mini-bus

NASA Astrophysics Data System (ADS)

Kim, Minjin; Sohn, Young-Jun; Lee, Won-Yong; Kim, Chang-Soo

The fuel cell/battery hybrid vehicle has been focused for the alternative engine of the existing internal-combustion engine due to the following advantages of the fuel cell and the battery. Firstly, the fuel cell is highly efficient and eco-friendly. Secondly, the battery has the fast response for the changeable power demand. However, the competitive efficiency of the hybrid fuel cell vehicle is necessary to successfully alternate the conventional vehicles with the fuel cell hybrid vehicle. The most relevant factor which affects the overall efficiency of the hybrid fuel cell vehicle is the relative engine sizing between the fuel cell and the battery. Therefore the design method to optimize the engine sizing of the fuel cell hybrid vehicle has been proposed. The target system is the fuel cell/battery hybrid mini-bus and its power distribution is controlled based on the fuzzy logic. The optimal engine sizes are determined based on the simulator developed in this paper. The simulator includes the several models for the fuel cell, the battery, and the major balance of plants. After the engine sizing, the system efficiency and the stability of the power distribution are verified based on the well-known driving schedule. Consequently, the optimally designed mini-bus shows good performance.

Effect of in vivo jet fuel exposure on subsequent in vitro dermal absorption of individual aromatic and aliphatic hydrocarbon fuel constituents.

PubMed

Muhammad, F; Monteiro-Riviere, N A; Baynes, R E; Riviere, J E

2005-05-14

The percutaneous absorption of topically applied jet fuel hydrocarbons (HC) through skin previously exposed to jet fuel has not been investigated, although this exposure scenario is the occupational norm. Pigs were exposed to JP-8 jet fuel-soaked cotton fabrics for 1 and 4 d with repeated daily exposures. Preexposed and unexposed skin was then dermatomed and placed in flow-through in vitro diffusion cells. Five cells with exposed skin and four cells with unexposed skin were dosed with a mixture of 14 different HC consisting of nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, ethyl benzene, o-xylene, trimethyl benzene (TMB), cyclohexyl benzene (CHB), naphthalene, and dimethyl naphthalene (DMN) in water + ethanol (50:50) as diluent. Another five cells containing only JP-8-exposed skin were dosed solely with diluent in order to determine the skin retention of jet fuel HC. The absorption parameters of flux, diffusivity, and permeability were calculated for the studied HC. The data indicated that there was a two-fold and four-fold increase in absorption of specific aromatic HC like ethyl benzene, o-xylene, and TMB through 1- and 4-dJP-8 preexposed skin, respectively. Similarly, dodecane and tridecane were absorbed more in 4-d than 1-dJP-8 preexposed skin experiments. The absorption of naphthalene and DMN was 1.5 times greater than the controls in both 1- and 4-d preexposures. CHB, naphthalene, and DMN had significant persistent skin retention in 4-d preexposures as compared to 1-d exposures that might leave skin capable of further absorption several days postexposure. The possible mechanism of an increase in HC absorption in fuel preexposed skin may be via lipid extraction from the stratum corneum as indicated by Fourier transform infrared (FTIR) spectroscopy. This study suggests that the preexposure of skin to jet fuel enhances the subsequent in vitro percutaneous absorption of HC, so single-dose absorption data for jet fuel HC from naive skin may not be optimal to predict the toxic potential for repeated exposures. For certain compounds, persistent absorption may occur days after the initial exposure.

Regenerative Fuel Cells for Space Power and Energy Conversion (NaBH4/H2O2 Fuel Cell Development)

NASA Technical Reports Server (NTRS)

Valdez, Thomas I.; Miley, George H.; Luo, Nie; Burton, Rodney; Mather, Joseph; Hawkins, Glenn; Byrd, Ethan; Gu, Lifeng; Shrestha, Prajakti Joshi

2006-01-01

A viewgraph presentation describing hydrogen peroxide and sodium borohydride development is shown. The topics include: 1) Motivation; 2) The Sodium Borohydride Fuel Cell; 3) Fuel Cell Comparisons; 4) MEA Optimization; 5) 500-Watt Stack Testing; 6) System Modeling: Fuel Cell Power Source for Lunar Rovers; and 7) Conclusions

Nanofluidic fuel cell

NASA Astrophysics Data System (ADS)

Lee, Jin Wook; Kjeang, Erik

2013-11-01

Fuel cells are gaining momentum as a critical component in the renewable energy mix for stationary, transportation, and portable power applications. State-of-the-art fuel cell technology benefits greatly from nanotechnology applied to nanostructured membranes, catalysts, and electrodes. However, the potential of utilizing nanofluidics for fuel cells has not yet been explored, despite the significant opportunity of harnessing rapid nanoscale reactant transport in close proximity to the reactive sites. In the present article, a nanofluidic fuel cell that utilizes fluid flow through nanoporous media is conceptualized and demonstrated for the first time. This transformative concept captures the advantages of recently developed membraneless and catalyst-free fuel cell architectures paired with the enhanced interfacial contact area enabled by nanofluidics. When compared to previously reported microfluidic fuel cells, the prototype nanofluidic fuel cell demonstrates increased surface area, reduced activation overpotential, superior kinetic characteristics, and moderately enhanced fuel cell performance in the high cell voltage regime with up to 14% higher power density. However, the expected mass transport benefits in the high current density regime were constrained by high ohmic cell resistance, which could likely be resolved through future optimization studies.

Fuel cell arrangement

DOEpatents

Isenberg, A.O.

1987-05-12

A fuel cell arrangement is provided wherein cylindrical cells of the solid oxide electrolyte type are arranged in planar arrays where the cells within a plane are parallel. Planes of cells are stacked with cells of adjacent planes perpendicular to one another. Air is provided to the interior of the cells through feed tubes which pass through a preheat chamber. Fuel is provided to the fuel cells through a channel in the center of the cell stack; the fuel then passes the exterior of the cells and combines with the oxygen-depleted air in the preheat chamber. 3 figs.

Fuel cell arrangement

DOEpatents

Isenberg, Arnold O.

1987-05-12

A fuel cell arrangement is provided wherein cylindrical cells of the solid oxide electrolyte type are arranged in planar arrays where the cells within a plane are parallel. Planes of cells are stacked with cells of adjacent planes perpendicular to one another. Air is provided to the interior of the cells through feed tubes which pass through a preheat chamber. Fuel is provided to the fuel cells through a channel in the center of the cell stack; the fuel then passes the exterior of the cells and combines with the oxygen-depleted air in the preheat chamber.

Lowering the temperature of solid oxide fuel cells.

PubMed

Wachsman, Eric D; Lee, Kang Taek

2011-11-18

Fuel cells are uniquely capable of overcoming combustion efficiency limitations (e.g., the Carnot cycle). However, the linking of fuel cells (an energy conversion device) and hydrogen (an energy carrier) has emphasized investment in proton-exchange membrane fuel cells as part of a larger hydrogen economy and thus relegated fuel cells to a future technology. In contrast, solid oxide fuel cells are capable of operating on conventional fuels (as well as hydrogen) today. The main issue for solid oxide fuel cells is high operating temperature (about 800°C) and the resulting materials and cost limitations and operating complexities (e.g., thermal cycling). Recent solid oxide fuel cells results have demonstrated extremely high power densities of about 2 watts per square centimeter at 650°C along with flexible fueling, thus enabling higher efficiency within the current fuel infrastructure. Newly developed, high-conductivity electrolytes and nanostructured electrode designs provide a path for further performance improvement at much lower temperatures, down to ~350°C, thus providing opportunity to transform the way we convert and store energy.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Kwan -Soo; Spendelow, Jacob Schatz; Choe, Yoong -Kee

Here, fuel cells are promising devices for clean power generation in a variety of economically and environmentally significant applications. Low-temperature proton exchange membrane (PEM) fuel cells utilizing Nafion require a high level of hydration, which limits the operating temperature to less than 100°C. In contrast, high-temperature PEM fuel cells utilizing phosphoric acid-doped polybenzimidazole can operate effectively up to 180°C; however, these devices degrade when exposed to water below 140°C. Here we present a different class of PEM fuel cells based on quaternary ammonium-biphosphate ion pairs that can operate under conditions unattainable with existing fuel cell technologies. These fuel cells exhibitmore » stable performance at 80–160°C with a conductivity decay rate more than three orders of magnitude lower than that of a commercial high-temperature PEM fuel cell. By increasing the operational flexibility, this class of fuel cell can simplify the requirements for heat and water management, and potentially reduce the costs associated with the existing fully functional fuel cell systems.« less

Organic fuel cell methods and apparatus

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram R. (Inventor); Frank, Harvey A. (Inventor); Halpert, Gerald (Inventor); Surampudi, Subbarao (Inventor); Prakash, G. K. Surya (Inventor); Vamos, Eugene (Inventor); Olah, George A. (Inventor)

2001-01-01

A liquid organic fuel cell is provided which employs a solid electrolyte membrane. An organic fuel, such as a methanol/water mixture, is circulated past an anode of a cell while oxygen or air is circulated past a cathode of the cell. The cell solid electrolyte membrane is preferably fabricated from Nafion.TM.. Additionally, a method for improving the performance of carbon electrode structures for use in organic fuel cells is provided wherein a high surface-area carbon particle/Teflon.TM.-binder structure is immersed within a Nafion.TM./methanol bath to impregnate the electrode with Nafion.TM.. A method for fabricating an anode for use in a organic fuel cell is described wherein metal alloys are deposited onto the electrode in an electro-deposition solution containing perfluorooctanesulfonic acid. A fuel additive containing perfluorooctanesulfonic acid for use with fuel cells employing a sulfuric acid electrolyte is also disclosed. New organic fuels, namely, trimethoxymethane, dimethoxymethane, and trioxane are also described for use with either conventional or improved fuel cells.

Organic fuel cell methods and apparatus

NASA Technical Reports Server (NTRS)

Surampudi, Subbarao (Inventor); Narayanan, Sekharipuram R. (Inventor); Vamos, Eugene (Inventor); Halpert, Gerald (Inventor); Olah, George A. (Inventor); Frank, Harvey A. (Inventor); Prakash, G. K. Surya (Inventor)

2004-01-01

A liquid organic, fuel cell is provided which employs a solid electrolyte membrane. An organic fuel, such as a methanol/water mixture, is circulated past an anode of a cell while oxygen or air is circulated past a cathode of the cell. The cell solid electrolyte membrane is preferably fabricated from Nafion.TM.. Additionally, a method for improving the performance of carbon electrode structures for use in organic fuel cells is provided wherein a high surface-area carbon particle/Teflon.TM.-binder structure is immersed within a Nafion.TM./methanol bath to impregnate the electrode with Nafion.TM.. A method for fabricating an anode for use in a organic fuel cell is described wherein metal alloys are deposited onto the electrode in an electro-deposition solution containing perfluorooctanesulfonic acid. A fuel additive containing perfluorooctanesulfonic acid for use with fuel cells employing a sulfuric acid electrolyte is also disclosed. New organic fuels, namely, trimethoxymethane, dimethoxymethane, and trioxane are also described for use with either conventional or improved fuel cells.

Organic fuel cell methods and apparatus

NASA Technical Reports Server (NTRS)

Frank, Harvey A. (Inventor); Halpert, Gerald (Inventor); Surampudi, Subbarao (Inventor); Olah, George A. (Inventor); Vamos, Eugene (Inventor); Narayanan, Sekharipuram R. (Inventor); Prakash, G. K. Surya (Inventor)

2008-01-01

A liquid organic, fuel cell is provided which employs a solid electrolyte membrane. An organic fuel, such as a methanol/water mixture, is circulated past an anode of a cell while oxygen or air is circulated past a cathode of the cell. The cell solid electrolyte membrane is preferably fabricated from Nafion.TM.. Additionally, a method for improving the performance of carbon electrode structures for use in organic fuel cells is provided wherein a high surface-area carbon particle/Teflon.TM.-binder structure is immersed within a Nafion.TM./methanol bath to impregnate the electrode with Nafion.TM.. A method for fabricating an anode for use in a organic fuel cell is described wherein metal alloys are deposited onto the electrode in an electro-deposition solution containing perfluorooctanesulfonic acid. A fuel additive containing perfluorooctanesulfonic acid for use with fuel cells employing a sulfuric acid electrolyte is also disclosed. New organic fuels, namely, trimethoxymethane, dimethoxymethane, and trioxane are also described for use with either conventional or improved fuel cells.

Aqueous liquid feed organic fuel cell using solid polymer electrolyte membrane

NASA Technical Reports Server (NTRS)

Olah, George A. (Inventor); Surampudi, Subbarao (Inventor); Vamos, Eugene (Inventor); Halpert, Gerald (Inventor); Narayanan, Sekharipuram R. (Inventor); Frank, Harvey A. (Inventor); Prakash, G. K. Surya (Inventor)

1997-01-01

A liquid organic fuel cell is provided which employs a solid electrolyte membrane. An organic fuel, such as a methanol/water mixture, is circulated past an anode of a cell while oxygen or air is circulated past a cathode of the cell. The cell solid electrolyte membrane is preferably fabricated from Nafion.TM.. Additionally, a method for improving the performance of carbon electrode structures for use in organic fuel cells is provided wherein a high surface-area carbon particle/Teflon.TM.-binder structure is immersed within a Nafion.TM./methanol bath to impregnate the electrode with Nafion.TM.. A method for fabricating an anode for use in a organic fuel cell is described wherein metal alloys are deposited onto the electrode in an electro-deposition solution containing perfluorooctanesulfonic acid. A fuel additive containing perfluorooctanesulfonic acid for use with fuel cells employing a sulfuric acid electrolyte is also disclosed. New organic fuels, namely, trimethoxymethane, dimethoxymethane, and trioxane are also described for use with either conventional or improved fuel cells.

Fuel-cell engine stream conditioning system

DOEpatents

DuBose, Ronald Arthur

2002-01-01

A stream conditioning system for a fuel cell gas management system or fuel cell engine. The stream conditioning system manages species potential in at least one fuel cell reactant stream. A species transfer device is located in the path of at least one reactant stream of a fuel cell's inlet or outlet, which transfer device conditions that stream to improve the efficiency of the fuel cell. The species transfer device incorporates an exchange media and a sorbent. The fuel cell gas management system can include a cathode loop with the stream conditioning system transferring latent and sensible heat from an exhaust stream to the cathode inlet stream of the fuel cell; an anode humidity retention system for maintaining the total enthalpy of the anode stream exiting the fuel cell related to the total enthalpy of the anode inlet stream; and a cooling water management system having segregated deionized water and cooling water loops interconnected by means of a brazed plate heat exchanger.

Heat recovery subsystem and overall system integration of fuel cell on-site integrated energy systems

NASA Technical Reports Server (NTRS)

Mougin, L. J.

1983-01-01

The best HVAC (heating, ventilating and air conditioning) subsystem to interface with the Engelhard fuel cell system for application in commercial buildings was determined. To accomplish this objective, the effects of several system and site specific parameters on the economic feasibility of fuel cell/HVAC systems were investigated. An energy flow diagram of a fuel cell/HVAC system is shown. The fuel cell system provides electricity for an electric water chiller and for domestic electric needs. Supplemental electricity is purchased from the utility if needed. An excess of electricity generated by the fuel cell system can be sold to the utility. The fuel cell system also provides thermal energy which can be used for absorption cooling, space heating and domestic hot water. Thermal storage can be incorporated into the system. Thermal energy is also provided by an auxiliary boiler if needed to supplement the fuel cell system output. Fuel cell/HVAC systems were analyzed with the TRACE computer program.

Hydrogen Fuel Cell Engines and Related Technologies

NASA Astrophysics Data System (ADS)

2001-12-01

The Hydrogen Fuel Cell Engines and Related Technologies report documents the first training course ever developed and made available to the transportation community and general public on the use hydrogen fuel cells in transportation. The course is designed to train a new generation of technicians in gaining a more complete understanding of the concepts, procedures, and technologies involved with hydrogen fuel cell use in transportation purposes. The manual contains 11 modules (chapters). The first eight modules cover (1) hydrogen properties, use and safety; and (2) fuel cell technology and its systems, fuel cell engine design and safety, and design and maintenance of a heavy duty fuel cell bus engine. The different types of fuel cells and hybrid electric vehicles are presented, however, the system descriptions and maintenance procedures focus on proton-exchange-membrane (PEM) fuel cells with respect to heavy duty transit applications. Modules 9 and 10 are intended to provide a better understanding of the acts, codes, regulations and guidelines concerning the use of hydrogen, as well as the safety guidelines for both hydrogen maintenance and fueling facilities. Module 11 presents a glossary and conversions.

Use of Multi-Functional Flexible Micro-Sensors for in situ Measurement of Temperature, Voltage and Fuel Flow in a Proton Exchange Membrane Fuel Cell

PubMed Central

Lee, Chi-Yuan; Chan, Pin-Cheng; Lee, Chung-Ju

2010-01-01

Temperature, voltage and fuel flow distribution all contribute considerably to fuel cell performance. Conventional methods cannot accurately determine parameter changes inside a fuel cell. This investigation developed flexible and multi-functional micro sensors on a 40 μm-thick stainless steel foil substrate by using micro-electro-mechanical systems (MEMS) and embedded them in a proton exchange membrane fuel cell (PEMFC) to measure the temperature, voltage and flow. Users can monitor and control in situ the temperature, voltage and fuel flow distribution in the cell. Thereby, both fuel cell performance and lifetime can be increased. PMID:22163545

Metabolic Profiling as Well as Stable Isotope Assisted Metabolic and Proteomic Analysis of RAW 264.7 Macrophages Exposed to Ship Engine Aerosol Emissions: Different Effects of Heavy Fuel Oil and Refined Diesel Fuel

PubMed Central

Sapcariu, Sean C.; Kanashova, Tamara; Dilger, Marco; Diabaté, Silvia; Oeder, Sebastian; Passig, Johannes; Radischat, Christian; Buters, Jeroen; Sippula, Olli; Streibel, Thorsten; Paur, Hanns-Rudolf; Schlager, Christoph; Mülhopt, Sonja; Stengel, Benjamin; Rabe, Rom; Harndorf, Horst; Krebs, Tobias; Karg, Erwin; Gröger, Thomas; Weiss, Carsten; Dittmar, Gunnar; Hiller, Karsten; Zimmermann, Ralf

2016-01-01

Exposure to air pollution resulting from fossil fuel combustion has been linked to multiple short-term and long term health effects. In a previous study, exposure of lung epithelial cells to engine exhaust from heavy fuel oil (HFO) and diesel fuel (DF), two of the main fuels used in marine engines, led to an increased regulation of several pathways associated with adverse cellular effects, including pro-inflammatory pathways. In addition, DF exhaust exposure was shown to have a wider response on multiple cellular regulatory levels compared to HFO emissions, suggesting a potentially higher toxicity of DF emissions over HFO. In order to further understand these effects, as well as to validate these findings in another cell line, we investigated macrophages under the same conditions as a more inflammation-relevant model. An air-liquid interface aerosol exposure system was used to provide a more biologically relevant exposure system compared to submerged experiments, with cells exposed to either the complete aerosol (particle and gas phase), or the gas phase only (with particles filtered out). Data from cytotoxicity assays were integrated with metabolomics and proteomics analyses, including stable isotope-assisted metabolomics, in order to uncover pathways affected by combustion aerosol exposure in macrophages. Through this approach, we determined differing phenotypic effects associated with the different components of aerosol. The particle phase of diluted combustion aerosols was found to induce increased cell death in macrophages, while the gas phase was found more to affect the metabolic profile. In particular, a higher cytotoxicity of DF aerosol emission was observed in relation to the HFO aerosol. Furthermore, macrophage exposure to the gas phase of HFO leads to an induction of a pro-inflammatory metabolic and proteomic phenotype. These results validate the effects found in lung epithelial cells, confirming the role of inflammation and cellular stress in the response to combustion aerosols. PMID:27348622

Aircraft Fuel Cell Power Systems

NASA Technical Reports Server (NTRS)

Needham, Robert

2004-01-01

In recent years, fuel cells have been explored for use in aircraft. While the weight and size of fuel cells allows only the smallest of aircraft to use fuel cells for their primary engines, fuel cells have showed promise for use as auxiliary power units (APUs), which power aircraft accessories and serve as an electrical backup in case of an engine failure. Fuel cell MUS are both more efficient and emit fewer pollutants. However, sea-level fuel cells need modifications to be properly used in aircraft applications. At high altitudes, the ambient air has a much lower pressure than at sea level, which makes it much more difficult to get air into the fuel cell to react and produce electricity. Compressors can be used to pressurize the air, but this leads to added weight, volume, and power usage, all of which are undesirable things. Another problem is that fuel cells require hydrogen to create electricity, and ever since the Hindenburg burst into flames, aircraft carrying large quantities of hydrogen have not been in high demand. However, jet fuel is a hydrocarbon, so it is possible to reform it into hydrogen. Since jet fuel is already used to power conventional APUs, it is very convenient to use this to generate the hydrogen for fuel-cell-based APUs. Fuel cells also tend to get large and heavy when used for applications that require a large amount of power. Reducing the size and weight becomes especially beneficial when it comes to fuel cells for aircraft. My goal this summer is to work on several aspects of Aircraft Fuel Cell Power System project. My first goal is to perform checks on a newly built injector rig designed to test different catalysts to determine the best setup for reforming Jet-A fuel into hydrogen. These checks include testing various thermocouples, transmitters, and transducers, as well making sure that the rig was actually built to the design specifications. These checks will help to ensure that the rig will operate properly and give correct results when it is finally ready for testing. Another of my goals is to test new membranes for use in proton-exchange membrane fuel cells, in the hope that these membranes can increase the electricity that is produced by he1 cells. Producing more electricity means that fewer fuel cells are needed, thus reducing the weight and volume of an APU based on fuel cells, making such an APU much more viable.

Evaluation of logistic and economic impacts of hybrid vehicle propulsion/microgrid concepts: Demonstration of LOCSS applied to HE HMMWV in future unit of action

NASA Astrophysics Data System (ADS)

Farrell, Michael; Tiberi, Lisa; Burns, Joseph; Udvare, Thomas B.

2006-05-01

Computer models have been developed and used to predict the performance of vehicles equipped with advanced fuel and power train technologies such as hybrid electric or fuel cells. However, simulations that describe the interaction of the vehicle with the rest of the vehicle fleet and infrastructure are just emerging. This paper documents the results of an experiment to demonstrate the utility of these types of simulations. The experiment examined the business case of fielding hybrid electric, high-mobility multipurpose wheeled vehicles (HE HMMWVs) in a future Army organization. The hypothesis was that fielding HE vehicles would significantly reduce fuel consumption due to the economy offered by the HE technology and reducing the number of generators as a result of using the vehicles to generate electrical power. The Logistical and Combat Systems Simulation (LOCSS) was used to estimate differences in fuel consumption and associated equipment during a 72-hour operation with and without HE HMMWVs. There was a 25 percent reduction in fuel consumption over the systems examined. However, due to the relatively low density of the HE vehicles in the organization, the total difference in fuel consumption was not operationally significant; and the savings in fuel costs did not overcome the additional procurement costs over a twenty-year life cycle.

Ocean Microbial Fuel Cell: Power Source and Research Tool for Studying Marine Biogeochemistry

NASA Astrophysics Data System (ADS)

Reimers, C. E.; Girguis, P.; Westall, J. C.; Nielsen, M. E.

2007-05-01

Ocean microbial fuel cells (OMFCs) are devices capable of producing modest levels of electrical power. The cells are ultimately driven by the oxidation of marine organic matter at the anode and reduction of dissolved oxygen at the cathode, but microbial transformations and electrochemically active intermediates play important roles in the overall process of electricity generation. By separating the factors that affect the performance of OMFCs into components of an equivalent circuit and manipulating these factors in laboratory and field experiments, we are gaining new insight into how specific redox reactions, sources of organic matter, and mass transport at small and intermediate scales may enrich environments with certain groups of microorganisms that in turn regulate anaerobic organic matter degradation. This talk will illustrate these relationships with the results from at least four experiments in which either fresh plankton, or substrates within continental margin sediments, fuelled the OMFCs. In each example, reduced sulfur compounds were found to be major electron carriers to the fuel cell anode. These intermediates came from a variety of sources including sulfide generated from sulfate reduction in mixed solutions surrounding the electrode, sulfide generated distally but transported by pore-water diffusion and advection, iron monosulfides and pyrite present is a sediment matrix centimeters from the electrode, and sulfide or polysulfide produced within an electrode biofilm. To illustrate a practical application of an OMFC, we are currently constructing a benthic cell that will power a sonic receiver in a network of underwater sensors. The form of this OMFC resembles a benthic chamber with a footprint of one square meter. It should be capable of supplying electrical power and regulating its output for years to decades.

Design, fabrication and performance evaluation of an integrated reformed methanol fuel cell for portable use

NASA Astrophysics Data System (ADS)

Zhang, Shubin; Zhang, Yufeng; Chen, Junyu; Yin, Congwen; Liu, Xiaowei

2018-06-01

In this paper, an integrated reformed methanol fuel cell (RMFC) as a portable power source is designed, fabricated and tested. The RMFC consists of a methanol steam reformer (MSR), a high temperature proton exchange membrane fuel cell (HT-PEMFC) stack, a microcontroller unit (MCU) and other auxiliaries. First, a system model based on Matlab/Simulink is established to investigate the mass and energy transport characteristics within the whole system. The simulation results suggest a hydrogen flow rate of at least 670 sccm is needed for the system to output 30 W and simultaneously maintain thermal equilibrium. Second, a metallic MSR and an HT-PEMFC stack with 12 cells are fabricated and tested. The tests show that the RMFC system is able to function normally when the performances of all the components meet the minimum requirements. At last, in the experiment of successfully powering a laptop, the RMFC system exhibits a stable performance during the complete work flow of all the phases, namely start-up, output and shutdown. Moreover, with a conservative design of 20 W power rating, maximum energy conversion efficiency of the RMFC system can be achieved (36%), and good stability in long-term operation is shown.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mehrabadi, Bahareh Alsadat Tavakoli; Dinh, Huyen N.; Bender, Guido

The performance loss and recovery of the fuel cell due to Balance of Plant (BOP) contaminants was identified via a combination of experimental data and a mathematical model. The experiments were designed to study the influence of organic contaminants (e.g. those from BOP materials) on the resistance of the catalyst, ionomer and membrane, and a mathematical model was developed that allowed us to separate these competing resistances from the data collected on an operating fuel cell. For this reason, based on the functional groups, four organic contaminants found in BOP materials, diethylene glycol monoethyl ether (DGMEE), diethylene glycol monoethyl ethermore » acetate (DGMEA), benzyl alcohol (BzOH) and 2,6-diaminotoluene (2,6-DAT) were infused separately to the cathode side of the fuel cell. The cell voltage and high frequency impedance resistance was measured as a function of time. The contaminant feed was then discontinued and voltage recovery was measured. It was determined that compounds with ion exchange properties like 2,6-DAT can cause voltage loss with non-reversible recovery, so this compound was studied in more detail. Finally, the degree of voltage loss increased with an increase in concentration, and/or infusion time, and increased with a decrease in catalyst loadings.« less

Using Fuel Cells to Increase the Range of Battery Electric Vehicles | News

Science.gov Websites

| NREL Using Fuel Cells to Increase the Range of Battery Electric Vehicles Using Fuel Cells to potential cost-effective scenarios for using small fuel cell power units to increase the range of medium fuel for range extension when necessary. By using hydrogen as a range-extending fuel, the BEV can

Sustainable and Renewable Energy Resources — Alternative Forms of Energy

NASA Astrophysics Data System (ADS)

Rao, M. C.

In order to move towards a sustainable existence in our critically energy dependent society there is a continuing need to adopt environmentally sustainable methods for energy production, storage and conversion. A fuel cell is an energy conversion device that generates electricity and heat by electrochemically combining a gaseous fuel and an oxidant gas through electrodes and across an ion conducting electrolyte. The use of fuel cells in both stationary and mobile power applications can offer significant advantages for the sustainable conversion of energy. Currently the cost of fuel cell systems is greater than that of similar, already available products, mainly because of small scale production and the lack of economies of scale. The best fuel for fuel cells is hydrogen and another barrier is fuel flexibility. Benefits arising from the use of fuel cells include efficiency and reliability, as well as economy, unique operating characteristics and planning flexibility and future development potential. By integrating the application of fuel cells, in series with renewable energy storage and production methods, sustainable energy requirements may be realized. As fuel cell application increases and improved fuel storage methods and handlings are developed, it is expected that the costs associated with fuel cell systems will fall dramatically in the future.

Proton exchange membrane fuel cell technology for transportation applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swathirajan, S.

1996-04-01

Proton Exchange Membrane (PEM) fuel cells are extremely promising as future power plants in the transportation sector to achieve an increase in energy efficiency and eliminate environmental pollution due to vehicles. GM is currently involved in a multiphase program with the US Department of Energy for developing a proof-of-concept hybrid vehicle based on a PEM fuel cell power plant and a methanol fuel processor. Other participants in the program are Los Alamos National Labs, Dow Chemical Co., Ballard Power Systems and DuPont Co., In the just completed phase 1 of the program, a 10 kW PEM fuel cell power plantmore » was built and tested to demonstrate the feasibility of integrating a methanol fuel processor with a PEM fuel cell stack. However, the fuel cell power plant must overcome stiff technical and economic challenges before it can be commercialized for light duty vehicle applications. Progress achieved in phase I on the use of monolithic catalyst reactors in the fuel processor, managing CO impurity in the fuel cell stack, low-cost electrode-membrane assembles, and on the integration of the fuel processor with a Ballard PEM fuel cell stack will be presented.« less

Fuel cell system with combustor-heated reformer

DOEpatents

Pettit, William Henry

2000-01-01

A fuel cell system including a fuel reformer heated by a catalytic combustor fired by anode effluent and/or fuel from a liquid fuel supply providing fuel for the fuel cell. The combustor includes a vaporizer section heated by the combustor exhaust gases for vaporizing the fuel before feeding it into the combustor. Cathode effluent is used as the principle oxidant for the combustor.

Single module pressurized fuel cell turbine generator system

DOEpatents

George, Raymond A.; Veyo, Stephen E.; Dederer, Jeffrey T.

2001-01-01

A pressurized fuel cell system (10), operates within a common pressure vessel (12) where the system contains fuel cells (22), a turbine (26) and a generator (98) where preferably, associated oxidant inlet valve (52), fuel inlet valve (56) and fuel cell exhaust valve (42) are outside the pressure vessel.

Fuel Cells: Power System Option for Space Research

NASA Astrophysics Data System (ADS)

Shaneeth, M.; Mohanty, Surajeet

2012-07-01

Fuel Cells are direct energy conversion devices and, thereby, they deliver electrical energy at very high efficiency levels. Hydrogen and Oxygen gases are electrochemically processed, producing clean electric power with water as the only by product. A typical, Fuel Cell based power system involve a Electrochemical power converter, gas storage and management systems, thermal management systems and relevant control units. While there exists different types of Fuel cells, Proton Exchange Membrane (PEM) Fuel Cells are considered as the most suitable one for portable applications. Generally, Fuel Cells are considered as the primary power system option in space missions requiring high power ( > 5kW) and long durations and also where water is a consumable, such as manned missions. This is primarily due to the advantage that fuel cell based power systems offer, in terms of specific energy. Fuel cells have the potential to attain specific energy > 500Wh/kg, specific power >500W/kg, energy density > 400Whr/L and also power density > 200 W/L. This apart, a fuel cell system operate totally independent of sun light, whereas as battery based system is fully dependent on the same. This uniqueness provides added flexibility and capabilities to the missions and modularity for power system. High power requiring missions involving reusable launch vehicles, manned missions etc are expected to be richly benefited from this. Another potential application of Fuel Cell would be interplanetary exploration. Unpredictable and dusty atmospheres of heavenly bodies limits sun light significantly and there fuel cells of different types, eg, Bio-Fuel Cells, PEMFC, DMFCs would be able to work effectively. Manned or unmanned lunar out post would require continuous power even during extra long lunar nights and high power levels are expected. Regenerative Fuel Cells, a combination of Fuel Cells and Electrolysers, are identified as strong candidate. While application of Fuel Cells in high power requiring missions is well established, as exemplified in Apollo and Space Shuttles, use in low power missions for science probes/rovers form a relatively newer area. Low power small fuel cells of this class are expected to bring in lot of operational convenience and freedom on onboard / extra terrestrial environment. Technological improvisations in the area, especially with regard to miniaturisation, and extra capabilities that the system offers, make it a strong candidate. The paper outlines features of fuel cells power systems, different types and their potential application scenarios, in the present context. It elucidates the extra capabilities and advantages, due to fuel cells, for different missions. Specific case analyses are also included.

Fuel Cell Seminar, 1992: Program and abstracts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-12-31

This year`s theme, ``Fuel Cells: Realizing the Potential,`` focuses on progress being made toward commercial manufacture and use of fuel cell products. Fuel cell power plants are competing for market share in some applications and demonstrations of market entry power plants are proceeding for additional applications. Development activity on fuel cells for transportation is also increasing; fuel cell products have potential in energy and transportation industries, with very favorable environmental impacts. This Seminar has the purpose of fostering communication by providing a forum for the international community interested in development, application, and business opportunities related fuel cells. Over 190 technicalmore » papers are included, the majority being processed for the data base.« less

Recent Progress in Nanostructured Electrocatalysts for PEM Fuel Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Sheng; Shao, Yuyan; Yin, Geping

2013-03-30

Polymer electrolyte membrane (PEM) fuel cells are attracting much attention as promising clean power sources and an alternative to conventional internal combustion engines, secondary batteries, and other power sources. Much effort from government laboratories, industry, and academia has been devoted to developing PEM fuel cells, and great advances have been achieved. Although prototype cars powered by fuel cells have been delivered, successful commercialization requires fuel cell electrocatalysts, which are crucial components at the heart of fuel cells, meet exacting performance targets. In this review, we present a brief overview of the recent progress in fuel cell electrocatalysts, which involves catalystmore » supports, Pt and Pt-based electrocatalysts, and non-Pt electrocatalysts.« less

The Business Case for Fuel Cells 2012. America's Partner in Power

DOE Office of Scientific and Technical Information (OSTI.GOV)

Curtin, Sandra; Gangi, Jennifer; Skukowski, Ryan

2012-12-01

This report, compiled by Fuel Cells 2000 with support from the Fuel Cell Technologies Program, profiles a select group of nationally recognizable companies and corporations that are deploying or demonstrating fuel cells. These businesses are taking advantage of a fuel cell's unique benefits, especially for powering lift trucks and providing combined heat and power to their stores and administrative offices.

Small Business Innovation Research Award Success Story: FuelCell Energy Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2011-08-31

This success story describes FuelCell Energy Inc., a small business that manufactures stationary fuel cells. In collaboration with Sustainable Innovations LLC, and with support from a Small Business Innovation Research (SBIR) Award from the U.S. Department of Energy's Fuel Cell Technologies Program, FuelCell Energy Inc. has developed a highly efficient solid state electrochemical hydrogen compressor.

Fuel cell added value for early market applications

NASA Astrophysics Data System (ADS)

Hardman, Scott; Chandan, Amrit; Steinberger-Wilckens, Robert

2015-08-01

Fuel Cells are often considered in the market place as just power providers. Whilst fuel cells do provide power, there are additional beneficial characteristics that should be highlighted to consumers. Due to the high price premiums associated with fuel cells, added value features need to be exploited in order to make them more appealing and increase unit sales and market penetration. This paper looks at the approach taken by two companies to sell high value fuel cells to niche markets. The first, SFC Energy, has a proven track record selling fuel cell power providers. The second, Bloom Energy, is making significant progress in the US by having sold its Energy Server to more than 40 corporations including Wal-Mart, Staples, Google, eBay and Apple. Further to these current markets, two prospective added value applications for fuel cells are discussed. These are fuel cells for aircraft APUs and fuel cells for fire prevention. These two existing markets and two future markets highlight that fuel cells are not just power providers. Rather, they can be used as solutions to many needs, thus being more cost effective by replacing a number of incumbent systems at the same time.

ECAS Phase I fuel cell results. [Energy Conservation Alternatives Study

NASA Technical Reports Server (NTRS)

Warshay, M.

1978-01-01

This paper summarizes and discusses the fuel cell system results of Phase I of the Energy Conversion Alternatives Study (ECAS). Ten advanced electric powerplant systems for central-station baseload generation using coal were studied by NASA in ECAS. Three types of low-temperature fuel cells (solid polymer electrolyte, SPE, aqueous alkaline, and phosphoric acid) and two types of high-temperature fuel cells (molten carbonate, MC, and zirconia solid electrolyte, SE) were studied. The results indicate that (1) overall efficiency increases with fuel cell temperature, and (2) scale-up in powerplant size can produce a significant reduction in cost of electricity (COE) only when it is accompanied by utilization of waste fuel cell heat through a steam bottoming cycle and/or integration with a gasifier. For low-temperature fuel cell systems, the use of hydrogen results in the highest efficiency and lowest COE. In spite of higher efficiencies, because of higher fuel cell replacement costs integrated SE systems have higher projected COEs than do integrated MC systems. Present data indicate that life can be projected to over 30,000 hr for MC fuel cells, but data are not yet sufficient for similarly projecting SE fuel cell life expectancy.

Fuel cells: A survey

NASA Technical Reports Server (NTRS)

Crowe, B. J.

1973-01-01

A survey of fuel cell technology and applications is presented. The operating principles, performance capabilities, and limitations of fuel cells are discussed. Diagrams of fuel cell construction and operating characteristics are provided. Photographs of typical installations are included.

Tubular screen electrical connection support for solid oxide fuel cells

DOEpatents

Tomlins, Gregory W.; Jaszcar, Michael P.

2002-01-01

A solid oxide fuel assembly is made of fuel cells (16, 16', 18, 24, 24', 26), each having an outer interconnection layer (36) and an outer electrode (28), which are disposed next to each other with rolled, porous, hollow, electrically conducting metal mesh conductors (20, 20') between the fuel cells, connecting the fuel cells at least in series along columns (15, 15') and where there are no metal felt connections between any fuel cells.

Carbon deposition and sulfur poisoning during CO2 electrolysis in nickel-based solid oxide cell electrodes

NASA Astrophysics Data System (ADS)

Skafte, Theis Løye; Blennow, Peter; Hjelm, Johan; Graves, Christopher

2018-01-01

Reduction of CO2 to CO and O2 in the solid oxide electrolysis cell (SOEC) has the potential to play a crucial role in closing the CO2 loop. Carbon deposition in nickel-based cells is however fatal and must be considered during CO2 electrolysis. Here, the effect of operating parameters is investigated systematically using simple current-potential experiments. Due to variations of local conditions, it is shown that higher current density and lower fuel electrode porosity will cause local carbon formation at the electrochemical reaction sites despite operating with a CO outlet concentration outside the thermodynamic carbon formation region. Attempts at mitigating the issue by coating the composite nickel/yttria-stabilized zirconia electrode with carbon-inhibiting nanoparticles and by sulfur passivation proved unsuccessful. Increasing the fuel electrode porosity is shown to mitigate the problem, but only to a certain extent. This work shows that a typical SOEC stack converting CO2 to CO and O2 is limited to as little as 15-45% conversion due to risk of carbon formation. Furthermore, cells operated in CO2-electrolysis mode are poisoned by reactant gases containing ppb-levels of sulfur, in contrast to ppm-levels for operation in fuel cell mode.

Electrochemical separation of hydrogen from reformate using PEM fuel cell technology

NASA Astrophysics Data System (ADS)

Gardner, C. L.; Ternan, M.

This article is an examination of the feasibility of electrochemically separating hydrogen obtained by steam reforming a hydrocarbon or alcohol source. A potential advantage of this process is that the carbon dioxide rich exhaust stream should be able to be captured and stored thereby reducing greenhouse gas emissions. Results are presented for the performance of the anode of proton exchange membrane (PEM) electrochemical cell for the separation of hydrogen from a H 2-CO 2 gas mixture and from a H 2-CO 2-CO gas mixture. Experiments were carried out using a single cell state-of-the-art PEM fuel cell. The anode was fed with either a H 2-CO 2 gas mixture or a H 2-CO 2-CO gas mixture and hydrogen was evolved at the cathode. All experiments were performed at room temperature and atmospheric pressure. With the H 2-CO 2 gas mixture the hydrogen extraction efficiency is quite high. When the gas mixture included CO, however, the hydrogen extraction efficiency is relatively poor. To improve the efficiency for the separation of the gas mixture containing CO, the effect of periodic pulsing on the anode potential was examined. Results show that pulsing can substantially reduce the anode potential thereby improving the overall efficiency of the separation process although the anode potential of the CO poisoned and pulsed cell still lies above that of an unpoisoned cell.

Simulation of a 250 kW diesel fuel processor/PEM fuel cell system

NASA Astrophysics Data System (ADS)

Amphlett, J. C.; Mann, R. F.; Peppley, B. A.; Roberge, P. R.; Rodrigues, A.; Salvador, J. P.

Polymer-electrolyte membrane (PEM) fuel cell systems offer a potential power source for utility and mobile applications. Practical fuel cell systems use fuel processors for the production of hydrogen-rich gas. Liquid fuels, such as diesel or other related fuels, are attractive options as feeds to a fuel processor. The generation of hydrogen gas for fuel cells, in most cases, becomes the crucial design issue with respect to weight and volume in these applications. Furthermore, these systems will require a gas clean-up system to insure that the fuel quality meets the demands of the cell anode. The endothermic nature of the reformer will have a significant affect on the overall system efficiency. The gas clean-up system may also significantly effect the overall heat balance. To optimize the performance of this integrated system, therefore, waste heat must be used effectively. Previously, we have concentrated on catalytic methanol-steam reforming. A model of a methanol steam reformer has been previously developed and has been used as the basis for a new, higher temperature model for liquid hydrocarbon fuels. Similarly, our fuel cell evaluation program previously led to the development of a steady-state electrochemical fuel cell model (SSEM). The hydrocarbon fuel processor model and the SSEM have now been incorporated in the development of a process simulation of a 250 kW diesel-fueled reformer/fuel cell system using a process simulator. The performance of this system has been investigated for a variety of operating conditions and a preliminary assessment of thermal integration issues has been carried out. This study demonstrates the application of a process simulation model as a design analysis tool for the development of a 250 kW fuel cell system.

In situ fluorescence spectroscopy correlates ionomer degradation to reactive oxygen species generation in an operating fuel cell.

PubMed

Prabhakaran, Venkateshkumar; Arges, Christopher G; Ramani, Vijay

2013-11-21

The rate of generation of reactive oxygen species (ROS) within the polymer electrolyte membrane (PEM) of an operating proton exchange member fuel cell (PEMFC) was monitored using in situ fluorescence spectroscopy. A modified barrier layer was introduced between the PEM and the electrocatalyst layer to eliminate metal-dye interactions and fluorescence resonance energy transfer (FRET) effects during measurements. Standard fuel cell operating parameters (temperature, relative humidity, and electrode potential) were systematically varied to evaluate their influence on the rate of ROS generation during PEMFC operation. Independently, the macroscopic rate of PEM degradation was measured by monitoring the fluoride ion emission rate (FER) in the effluent stream at each operating condition. The ROS generation reaction rate constant (estimated from the in situ fluorescence experiments) correlated perfectly with the measured FER across all conditions, demonstrating unequivocally for the first time that a direct correlation exists between in situ ROS generation and PEM macroscopic degradation. The activation energy for ROS generation within the PEM was estimated to be 12.5 kJ mol(-1).

Effect of temperature on a miniaturized microbial fuel cell (MFC)

NASA Astrophysics Data System (ADS)

Ren, Hao; Jiang, Chenming; Chae, Junseok

2017-12-01

A microbial fuel cell (MFC) is a bioinspired energy converter which directly converts biomass into electricity through the catalytic activity of a specific species of bacteria. The effect of temperature on a miniaturized microbial fuel cell with Geobacter sulfurreducens dominated mixed inoculum is investigated in this paper for the first time. The miniaturized MFC warrants investigation due to its small thermal mass, and a customized setup is built for the temperature effect characterization. The experiment demonstrates that the optimal temperature for the miniaturized MFC is 322-326 K (49-53 °C). When the temperature is increased from 294 to 322 K, a remarkable current density improvement of 282% is observed, from 2.2 to 6.2 Am-2. Furthermore, we perform in depth analysis on the effect of temperature on the miniaturized MFC, and found that the activation energy for the current limiting mechanism of the MFC is approximately between 0.132 and 0.146 eV, and the result suggest that the electron transfer between cytochrome c is the limiting process for the miniaturized MFC.

Fuel cell having dual electrode anode or cathode

DOEpatents

Findl, Eugene

1985-01-01

A fuel cell that is characterized by including a dual electrode anode that is operable to simultaneously electro-oxidize a gaseous fuel and a liquid fuel. In alternative embodiments, a fuel cell having a single electrode anode is provided with a dual electrode cathode that is operable to simultaneously reduce a gaseous oxidant and a liquid oxidant to electro-oxidize a fuel supplied to the cell.

Fuel cell having dual electrode anode or cathode

DOEpatents

Findl, E.

1984-04-10

A fuel cell that is characterized by including a dual electrode anode that is operable to simultaneously electro-oxidize a gaseous fuel and a liquid fuel. In alternative embodiments, a fuel cell having a single electrode anode is provided with a dual electrode cathode that is operable to simultaneously reduce a gaseous oxidant and a liquid oxidant to electro-oxidize a fuel supplied to the cell.

Low hydrostatic head electrolyte addition to fuel cell stacks

DOEpatents

Kothmann, Richard E.

1983-01-01

A fuel cell and system for supply electrolyte, as well as fuel and an oxidant to a fuel cell stack having at least two fuel cells, each of the cells having a pair of spaced electrodes and a matrix sandwiched therebetween, fuel and oxidant paths associated with a bipolar plate separating each pair of adjacent fuel cells and an electrolyte fill path for adding electrolyte to the cells and wetting said matrices. Electrolyte is flowed through the fuel cell stack in a back and forth fashion in a path in each cell substantially parallel to one face of opposite faces of the bipolar plate exposed to one of the electrodes and the matrices to produce an overall head uniformly between cells due to frictional pressure drop in the path for each cell free of a large hydrostatic head to thereby avoid flooding of the electrodes. The bipolar plate is provided with channels forming paths for the flow of the fuel and oxidant on opposite faces thereof, and the fuel and the oxidant are flowed along a first side of the bipolar plate and a second side of the bipolar plate through channels formed into the opposite faces of the bipolar plate, the fuel flowing through channels formed into one of the opposite faces and the oxidant flowing through channels formed into the other of the opposite faces.

Solid polymer electrolyte (SPE) fuel cell technology program, phase 1/1A. [design and fabrication

NASA Technical Reports Server (NTRS)

1975-01-01

A solid polymer electrolyte fuel cell was studied for the purpose of improving the characteristics of the technology. Several facets were evaluated, namely: (1) reduced fuel cell costs; (2) reduced fuel cell weight; (3) improved fuel cell efficiency; and (4) increased systems compatibility. Demonstrated advances were incorporated into a full scale hardware design. A single cell unit was fabricated. A substantial degree of success was demonstrated.

Hydrogen fuel cell engines and related technologies

DOT National Transportation Integrated Search

2001-12-01

The manual documents the first training course developed on the use of hydrogen fuel cells in transportation. The manual contains eleven modules covering hydrogen properties, use and safety; fuel cell technology and its systems, fuel cell engine desi...

Fuel cell sub-assembly

DOEpatents

Chi, Chang V.

1983-01-01

A fuel cell sub-assembly comprising a plurality of fuel cells, a first section of a cooling means disposed at an end of the assembly and means for connecting the fuel cells and first section together to form a unitary structure.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wheeler, Douglas; Ulsh, Michael

The results of two Manufacturing Readiness Assessments of PEM fuel cell stacks and material handling equipment (MHE) and backup power (BUP) PEM fuel cell systems are given. Design modifications of fuel cell systems were made because the initial, 2008 designs did not fully meet the operational requirements of the markets. This situation indicates the 2008 risk elements were overstated.For 2010 BUP and MHE fuel cell systems, manufacturers had not reached the Low Rate Initial Production (LRIP) defined in the 2008 MRA Report at 1,000 units per year per manufacturer.For fuel cell stacks, LRIP was demonstrated by more than one manufacturer.Themore » federal tax incentive program has compensated for the initial high cost of fuel cell systems.The Balance-of-Plant (BOP) has not evolved as rapidly as the PEM fuel cell stack manufacturing readiness.The BOP in 2014 is as costly as the fuel cell stack for MHE applications.« less

PEM Fuel Cells Redesign Using Biomimetic and TRIZ Design Methodologies

NASA Astrophysics Data System (ADS)

Fung, Keith Kin Kei

Two formal design methodologies, biomimetic design and the Theory of Inventive Problem Solving, TRIZ, were applied to the redesign of a Proton Exchange Membrane (PEM) fuel cell. Proof of concept prototyping was performed on two of the concepts for water management. The liquid water collection with strategically placed wicks concept demonstrated the potential benefits for a fuel cell. Conversely, the periodic flow direction reversal concepts might cause a potential reduction water removal from a fuel cell. The causes of this water removal reduction remain unclear. In additional, three of the concepts generated with biomimetic design were further studied and demonstrated to stimulate more creative ideas in the thermal and water management of fuel cells. The biomimetic design and the TRIZ methodologies were successfully applied to fuel cells and provided different perspectives to the redesign of fuel cells. The methodologies should continue to be used to improve fuel cells.

Alkaline RFC Space Station prototype - 'Next step Space Station'. [Regenerative Fuel Cells

NASA Technical Reports Server (NTRS)

Hackler, I. M.

1986-01-01

The regenerative fuel cell, a candidate technology for the Space Station's energy storage system, is described. An advanced development program was initiated to design, manufacture, and integrate a regenerative fuel cell Space Station prototype (RFC SSP). The RFC SSP incorporates long-life fuel cell technology, increased cell area for the fuel cells, and high voltage cell stacks for both units. The RFC SSP's potential for integration with the Space Station's life support and propulsion systems is discussed.

Investigation of Micro- and Macro-Scale Transport Processes for Improved Fuel Cell Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gu, Wenbin

2014-08-29

This report documents the work performed by General Motors (GM) under the Cooperative agreement No. DE-EE0000470, “Investigation of Micro- and Macro-Scale Transport Processes for Improved Fuel Cell Performance,” in collaboration with the Penn State University (PSU), University of Tennessee Knoxville (UTK), Rochester Institute of Technology (RIT), and University of Rochester (UR) via subcontracts. The overall objectives of the project are to investigate and synthesize fundamental understanding of transport phenomena at both the macro- and micro-scales for the development of a down-the-channel model that accounts for all transport domains in a broad operating space. GM as a prime contractor focused onmore » cell level experiments and modeling, and the Universities as subcontractors worked toward fundamental understanding of each component and associated interface.« less

3-Dimensional Computational Fluid Dynamics Modeling of Solid Oxide Fuel Cell Using Different Fuels

DTIC Science & Technology

2011-01-01

major types of fuel cells in practice are listed below: Polymer Electrolyte Membrane Fuel Cell ( PEMFC ) Alkaline Fuel cell (AFC) Phosphoric Acid...Material Operating Temperature (oC) Efficiency (%) PEMFC H2, Methanol, Formic Acid Hydrated Organic Polymer < 90 40-50 AFC Pure H2 Aqueous

Transport Phenomena and Interfacial Kinetics in Planar Microfluidic Membraneless Fuel Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abruna, Hector Daniel

2013-08-01

Our work is focused on membraneless laminar flow fuel cells, an unconventional fuel cell technology, intended to create a system that not only avoids most typical fuel cell drawbacks, but also achieves the highest power density yet recorded for a non-H{sub 2} fuel cell. We have employed rigorous electrochemistry to characterize the high-energy- density fuel BH4-, providing important mechanistic insight for anode catalyst choice and avoiding deleterious side reactions. Numerous fuel cell oxidants, used in place of O{sub 2}, are compared in a detailed, uniform manner, and a powerful new oxidant, cerium ammonium nitrate (CAN), is described. The high-voltage BH{submore » 4}{sup -}/CAN fuel/oxidant combination is employed in a membraneless, room temperature, laminar-flow fuel cell, with herringbone micromixers which provide chaotic-convective flow which, in turn, enhances both the power output and efficiency of the device. We have also been involved in the design of a scaled-up version of the membraneless laminar flow fuel cell intended to provide a 10W output.« less

Fuel cells feasibility

NASA Technical Reports Server (NTRS)

Schonfeld, D.; Charng, T.

1981-01-01

The technical and economic status of fuel cells is assessed with emphasis on their potential benefits to the Deep Space Network. The fuel cell, what it is, how it operates, and what its outputs are, is reviewed. Major technical problems of the fuel cell and its components are highlighted. Due to these problems and economic considerations it is concluded that fuel cells will not become commercially viable until the early 1990s.

Improved Round Trip Efficiency for Regenerative Fuel Cell Systems

DTIC Science & Technology

2012-05-11

advanced components that enable closed-loop, zero emission, low signature energy storage. The system utilizes proton exchange membrane ( PEM ) fuel cell ...regenerative fuel cell (RFC) systems based on proton exchange membrane ( PEM ) technology. An RFC consists of a fuel cell powerplant, an electrolysis...based on an air independent, hydrogen-oxygen, PEM RFC is feasible within the near term if development efforts proceed forward. Fuel Cell

Flexible ceramic gasket for SOFC generator

DOEpatents

Zafred, Paolo [Murrysville, PA; Prevish, Thomas [Trafford, PA

2009-02-03

A solid oxide fuel cell generator (10) contains stacks of hollow axially elongated fuel cells (36) having an open top end (37), an oxidant inlet plenum (52), a feed fuel plenum (11), a combustion chamber (94) for combusting reacted oxidant/spent fuel; and, optionally, a fuel recirculation chamber (106) below the combustion chamber (94), where the fuel recirculation chamber (94) is in part defined by semi-porous fuel cell positioning gasket (108), all within an outer generator enclosure (8), wherein the fuel cell gasket (108) has a laminate structure comprising at least a compliant fibrous mat support layer and a strong, yet flexible woven layer, which may contain catalytic particles facing the combustion chamber, where the catalyst, if used, is effective to further oxidize exhaust fuel and protect the open top end (37) of the fuel cells.

75 FR 11873 - Notice of Fuel Cell Pre-Solicitation Workshop

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-12

... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Notice of Fuel Cell Pre... Cell Pre-Solicitation Workshop. SUMMARY: The Fuel Cell Technologies Program, under the DOE Office of Energy Efficiency and Renewable Energy, is inviting the fuel cell research community and other...

An Assessment of the Challenges Associated with Individual Battlefield Power: Addressing the Power Budget Burdens of the Warfighter and Squad

DTIC Science & Technology

2014-05-01

Fuel Cells —JP8 Fuel Cells Aerial ResupplyBATMAN Advanced Battery Technologies Conformal Battery Nett Warrior Carried C-IED N at ic k O E C...Advanced Solar Inductive Charging Kinetic Harvesting Fuel Cells JP8 Fuel Cells Aerial ResupplyBATMAN Advanced Battery Technologies Conformal...90 lbs. of some from of energy during the mission  Ideally, this would be some expendable fuel , perhaps for fuel cells  Otherwise it creates

Methanol Fuel Cell

NASA Technical Reports Server (NTRS)

Voecks, G. E.

1985-01-01

In proposed fuel-cell system, methanol converted to hydrogen in two places. External fuel processor converts only part of methanol. Remaining methanol converted in fuel cell itself, in reaction at anode. As result, size of fuel processor reduced, system efficiency increased, and cost lowered.

A direct borohydride fuel cell with a polymer fiber membrane and non-noble metal catalysts.

PubMed

Yang, Xiaodong; Liu, Yongning; Li, Sai; Wei, Xiaozhu; Wang, Li; Chen, Yuanzhen

2012-01-01

Polymer electrolyte membranes (PEM) and Pt-based catalysts are two crucial components which determine the properties and price of fuel cells. Even though, PEM faces problem of fuel crossover in liquid fuel cells such as direct methanol fuel cell (DMFC) and direct borohydride fuel cell (DBFC), which lowers power output greatly. Here, we report a DBFC in which a polymer fiber membrane (PFM) was used, and metal oxides, such as LaNiO₃ and MnO₂, were used as cathode catalysts, meanwhile CoO was used as anode catalyst. Peak power density of 663 mW·cm⁻² has been achieved at 65°C, which increases by a factor of 1.7-3.7 compared with classic DBFCs. This fuel cell structure can also be extended to other liquid fuel cells, such as DMFC.

On-site fuel cell field test support program

NASA Astrophysics Data System (ADS)

Staniunas, J. W.; Merten, G. P.

1982-01-01

In order to assess the impact of grid connection on the potential market for fuel cell service, applications studies were conducted to identify the fuel cell operating modes and corresponding fuel cell sizing criteria which offer the most potential for initial commercial service. The market for grid-connected fuel cell service was quantified using United's market analysis program and computerized building data base. Electric and gas consumption data for 268 buildings was added to our surveyed building data file, bringing the total to 407 buildings. These buildings were analyzed for grid-isolated and grid-connected fuel cell service. The results of the analyses indicated that the nursing home, restaurant and health club building sectors offer significant potential for fuel cell service.

Fuel-Cell-Powered Electric Motor Drive Analyzed for a Large Airplane

NASA Technical Reports Server (NTRS)

Brown, Gerald V.; Choi, Benjamin B.

2005-01-01

Because of its high efficiency, fuel cell technology may be used to launch a new generation of more-electric aeropropulsion and power systems for future aircraft. Electric-motor-driven airplanes using fuel-cell powerplants would be beneficial to the environment because of fuel savings, low noise, and zero carbon-dioxide emissions. In spite of the fuel cell s efficiency benefit, to produce the same shaft drive power, a fuel cell- powered electric-drive system must be definitely heavier than a turbine-drive system. However, the fuel-cell system s overall efficiency from fuel-to-shaft power is higher than for a turbine-drive system. This means that the fuel consumption rate could be lower than for a conventional system. For heavier, fuel-laden planes for longer flights, we might achieve substantial fuel savings. In the airplane industry, in fact, an efficiency gain of even a few percentage points can make a major economic difference in operating costs.

Planar solid oxide fuel cell with staged indirect-internal air and fuel preheating and reformation

DOEpatents

Geisbrecht, Rodney A; Williams, Mark C

2003-10-21

A solid oxide fuel cell arrangement and method of use that provides internal preheating of both fuel and air in order to maintain the optimum operating temperature for the production of energy. The internal preheat passes are created by the addition of two plates, one on either side of the bipolar plate, such that these plates create additional passes through the fuel cell. This internal preheat fuel cell configuration and method reduce the requirements for external heat exchanger units and air compressors. Air or fuel may be added to the fuel cell as required to maintain the optimum operating temperature through a cathode control valve or an anode control valve, respectively. A control loop comprises a temperature sensing means within the preheat air and fuel passes, a means to compare the measured temperature to a set point temperature and a determination based on the comparison as to whether the control valves should allow additional air or fuel into the preheat or bypass manifolds of the fuel cell.

Variable area fuel cell process channels

DOEpatents

Kothmann, Richard E.

1981-01-01

A fuel cell arrangement having a non-uniform distribution of fuel and oxidant flow paths, on opposite sides of an electrolyte matrix, sized and positioned to provide approximately uniform fuel and oxidant utilization rates, and cell conditions, across the entire cell.

Molten Carbonate and Phosphoric Acid Stationary Fuel Cells: Overview and Gap Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Remick, R.; Wheeler, D.

2010-09-01

This report describes the technical and cost gap analysis performed to identify pathways for reducing the costs of molten carbonate fuel cell (MCFC) and phosphoric acid fuel cell (PAFC) stationary fuel cell power plants.

Demonstrating a Total Transit Solution for Fuel Cell Electric Buses in Boston

DOT National Transportation Integrated Search

2017-05-01

The Federal Transit Administrations (FTA) National Fuel Cell Bus Program (NFCBP) focuses on developing commercially viable fuel cell bus technologies. Nuvera is leading the Massachusetts Fuel Cell Bus project to demonstrate a complete transit solu...

Micro-tubular flame-assisted fuel cells for micro-combined heat and power systems

NASA Astrophysics Data System (ADS)

Milcarek, Ryan J.; Wang, Kang; Falkenstein-Smith, Ryan L.; Ahn, Jeongmin

2016-02-01

Currently the role of fuel cells in future power generation is being examined, tested and discussed. However, implementing systems is more difficult because of sealing challenges, slow start-up and complex thermal management and fuel processing. A novel furnace system with a flame-assisted fuel cell is proposed that combines the thermal management and fuel processing systems by utilizing fuel-rich combustion. In addition, the flame-assisted fuel cell furnace is a micro-combined heat and power system, which can produce electricity for homes or businesses, providing resilience during power disruption while still providing heat. A micro-tubular solid oxide fuel cell achieves a significant performance of 430 mW cm-2 operating in a model fuel-rich exhaust stream.

Fuel cell on-site integrated energy system parametric analysis of a residential complex

NASA Technical Reports Server (NTRS)

Simons, S. N.

1977-01-01

A parametric energy-use analysis was performed for a large apartment complex served by a fuel cell on-site integrated energy system (OS/IES). The variables parameterized include operating characteristics for four phosphoric acid fuel cells, eight OS/IES energy recovery systems, and four climatic locations. The annual fuel consumption for selected parametric combinations are presented and a breakeven economic analysis is presented for one parametric combination. The results show fuel cell electrical efficiency and system component choice have the greatest effect on annual fuel consumption; fuel cell thermal efficiency and geographic location have less of an effect.

Magnetic resonance imaging of water content across the Nafion membrane in an operational PEM fuel cell.

PubMed

Zhang, Ziheng; Martin, Jonathan; Wu, Jinfeng; Wang, Haijiang; Promislow, Keith; Balcom, Bruce J

2008-08-01

Water management is critical to optimize the operation of polymer electrolyte membrane fuel cells. At present, numerical models are employed to guide water management in such fuel cells. Accurate measurements of water content variation in polymer electrolyte membrane fuel cells are required to validate these models and to optimize fuel cell behavior. We report a direct water content measurement across the Nafion membrane in an operational polymer electrolyte membrane fuel cell, employing double half k-space spin echo single point imaging techniques. The MRI measurements with T2 mapping were undertaken with a parallel plate resonator to avoid the effects of RF screening. The parallel plate resonator employs the electrodes inherent to the fuel cell to create a resonant circuit at RF frequencies for MR excitation and detection, while still operating as a conventional fuel cell at DC. Three stages of fuel cell operation were investigated: activation, operation and dehydration. Each profile was acquired in 6 min, with 6 microm nominal resolution and a SNR of better than 15.

Carbon fuel particles used in direct carbon conversion fuel cells

DOEpatents

Cooper, John F.; Cherepy, Nerine

2012-10-09

A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

Carbon Fuel Particles Used in Direct Carbon Conversion Fuel Cells

DOEpatents

Cooper, John F.; Cherepy, Nerine

2008-10-21

A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

Carbon fuel particles used in direct carbon conversion fuel cells

DOEpatents

Cooper, John F [Oakland, CA; Cherepy, Nerine [Oakland, CA

2011-08-16

A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

Carbon fuel particles used in direct carbon conversion fuel cells

DOEpatents

Cooper, John F [Oakland, CA; Cherepy, Nerine [Oakland, CA

2012-01-24

A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

Thermodynamic analysis of biofuels as fuels for high temperature fuel cells

NASA Astrophysics Data System (ADS)

Milewski, Jarosław; Bujalski, Wojciech; Lewandowski, Janusz

2011-11-01

Based on mathematical modeling and numerical simulations, applicativity of various biofuels on high temperature fuel cell performance are presented. Governing equations of high temperature fuel cell modeling are given. Adequate simulators of both solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC) have been done and described. Performance of these fuel cells with different biofuels is shown. Some characteristics are given and described. Advantages and disadvantages of various biofuels from the system performance point of view are pointed out. An analysis of various biofuels as potential fuels for SOFC and MCFC is presented. The results are compared with both methane and hydrogen as the reference fuels. The biofuels are characterized by both lower efficiency and lower fuel utilization factors compared with methane. The presented results are based on a 0D mathematical model in the design point calculation. The governing equations of the model are also presented. Technical and financial analysis of high temperature fuel cells (SOFC and MCFC) are shown. High temperature fuel cells can be fed by biofuels like: biogas, bioethanol, and biomethanol. Operational costs and possible incomes of those installation types were estimated and analyzed. A comparison against classic power generation units is shown. A basic indicator net present value (NPV) for projects was estimated and commented.

Thermodynamic analysis of biofuels as fuels for high temperature fuel cells

NASA Astrophysics Data System (ADS)

Milewski, Jarosław; Bujalski, Wojciech; Lewandowski, Janusz

2013-02-01

Based on mathematical modeling and numerical simulations, applicativity of various biofuels on high temperature fuel cell performance are presented. Governing equations of high temperature fuel cell modeling are given. Adequate simulators of both solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC) have been done and described. Performance of these fuel cells with different biofuels is shown. Some characteristics are given and described. Advantages and disadvantages of various biofuels from the system performance point of view are pointed out. An analysis of various biofuels as potential fuels for SOFC and MCFC is presented. The results are compared with both methane and hydrogen as the reference fuels. The biofuels are characterized by both lower efficiency and lower fuel utilization factors compared with methane. The presented results are based on a 0D mathematical model in the design point calculation. The governing equations of the model are also presented. Technical and financial analysis of high temperature fuel cells (SOFC and MCFC) are shown. High temperature fuel cells can be fed by biofuels like: biogas, bioethanol, and biomethanol. Operational costs and possible incomes of those installation types were estimated and analyzed. A comparison against classic power generation units is shown. A basic indicator net present value (NPV) for projects was estimated and commented.

Liquid-fueled SOFC power sources for transportation

NASA Astrophysics Data System (ADS)

Myles, K. M.; Doshi, R.; Kumar, R.; Krumpelt, M.

Traditionally, fuel cells have been developed for space or stationary terrestrial applications. As the first commercial 200-kW systems were being introduced by ONSI and Fuji Electric, the potentially much larger, but also more challenging, application in transportation was beginning to be addressed. As a result, fuel cell-powered buses have been designed and built, and R&D programs for fuel cell-powered passenger cars have been initiated. The engineering challenge of eventually replacing the internal combustion engine in buses, trucks, and passenger cars with fuel cell systems is to achieve much higher power densities and much lower costs than obtainable in systems designed for stationary applications. At present, the leading fuel cell candidate for transportation applications is, without question, the polymer electrolyte fuel cell (PEFC). Offering ambient temperature start-up and the potential for a relatively high power density, the polymer technology has attracted the interest of automotive manufacturers worldwide. But the difficulties of fuel handling for the PEFC have led to a growing interest in exploring the prospects for solid oxide fuel cells (SOFCs) operating on liquid fuels for transportation applications. Solid oxide fuel cells are much more compatible with liquid fuels (methanol or other hydrocarbons) and are potentially capable of power densities high enough for vehicular use. Two SOFC options for such use are discussed in this report.

A preliminary study of a miniature planar 6-cell PEMFC stack combined with a small hydrogen storage canister

NASA Astrophysics Data System (ADS)

Zhang, Xigui; Zheng, Dan; Wang, Tao; Chen, Cong; Cao, Jianyu; Yan, Jian; Wang, Wenming; Liu, Juanying; Liu, Haohan; Tian, Juan; Li, Xinxin; Yang, Hui; Xia, Baojia

The fabrication and performance evaluation of a miniature 6-cell PEMFC stack based on Micro-Electronic-Mechanical-System (MEMS) technology is presented in this paper. The stack with a planar configuration consists of 6-cells in serial interconnection by spot welding one cell anode with another cell cathode. Each cell was made by sandwiching a membrane-electrode-assembly (MEA) between two flow field plates fabricated by a classical MEMS wet etching method using silicon wafer as the original material. The plates were made electrically conductive by sputtering a Ti/Pt/Au composite metal layer on their surfaces. The 6-cells lie in the same plane with a fuel buffer/distributor as their support, which was fabricated by the MEMS silicon-glass bonding technology. A small hydrogen storage canister was used as fuel source. Operating on dry H 2 at a 40 ml min -1 flow rate and air-breathing conditions at room temperature and atmospheric pressure, the linear polarization experiment gave a measured peak power of 0.9 W at 250 mA cm -2 for the stack and average power density of 104 mW cm -2 for each cell. The results suggested that the stack has reasonable performance benefiting from an even fuel supply. But its performance tended to deteriorate with power increase, which became obvious at 600 mW. This suggests that the stack may need some power assistance, from say supercapacitors to maintain its stability when operated at higher power.

A distributed real-time model of degradation in a solid oxide fuel cell, part II: Analysis of fuel cell performance and potential failures

NASA Astrophysics Data System (ADS)

Zaccaria, V.; Tucker, D.; Traverso, A.

2016-09-01

Solid oxide fuel cells are characterized by very high efficiency, low emissions level, and large fuel flexibility. Unfortunately, their elevated costs and relatively short lifetimes reduce the economic feasibility of these technologies at the present time. Several mechanisms contribute to degrade fuel cell performance during time, and the study of these degradation modes and potential mitigation actions is critical to ensure the durability of the fuel cell and their long-term stability. In this work, localized degradation of a solid oxide fuel cell is modeled in real-time and its effects on various cell parameters are analyzed. Profile distributions of overpotential, temperature, heat generation, and temperature gradients in the stack are investigated during degradation. Several causes of failure could occur in the fuel cell if no proper control actions are applied. A local analysis of critical parameters conducted shows where the issues are and how they could be mitigated in order to extend the life of the cell.

MEMS-based thin-film fuel cells

DOEpatents

Jankowksi, Alan F.; Morse, Jeffrey D.

2003-10-28

A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

Status of solid polymer electrolyte fuel cell technology and potential for transportation applications

NASA Astrophysics Data System (ADS)

McElroy, J. F.; Nuttall, L. J.

The solid polymer electrolyte (SPE) fuel cell represents the first fuel cell technology known to be used operationally. Current activities are mainly related to the development of a space regenerative fuel cell system for energy storage on board space stations, or other large orbiting vehicles and platforms. During 1981, a study was performed to determine the feasibility of using SPE fuel cells for automotive or other vehicular applications, using methanol as the fuel. The results of this study were very encouraging. Details concerning a conceptual automotive fuel cell power plant study are discussed, taking into account also a layout of major components for compact passenger car installation.

FUEL CELL ENERGY RECOVERY FROM LANDFILL GAS

EPA Science Inventory

International Fuel Cells Corporation is conducting a US Environmental Protection Agency (EPA) sponsored program to demonstrate energy recovery from landfill gas using a commercial phosphoric acid fuel cell power plant. The US EPA is interested in fuel cells for this application b...

Low cost, lightweight fuel cell elements

NASA Technical Reports Server (NTRS)

Kindler, Andrew (Inventor)

2001-01-01

New fuel cell elements for use in liquid feed fuel cells are provided. The elements including biplates and endplates are low in cost, light in weight, and allow high efficiency operation. Electrically conductive elements are also a part of the fuel cell elements.

Block Copolymers for Alkaline Fuel Cell Membrane Materials

DTIC Science & Technology

2014-07-30

temperature fuel cells including proton exchange membrane fuel cell ( PEMFC ) and alkaline fuel cell (AFC) with operation temperature usually lower than 120...advantages over proton exchange membrane fuel cells ( PEMFCs ) resulting in the popularity of AFCs in the US space program.[8-11] The primary benefit AFC...offered over PEMFC is better electrochemical kinetics on the anode and cathode under the alkaline environment, which results in the ability to use

Compact Fuel-Cell System Would Consume Neat Methanol

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram; Kindler, Andrew; Valdez, Thomas

2007-01-01

In a proposed direct methanol fuel-cell electric-power-generating system, the fuel cells would consume neat methanol, in contradistinction to the dilute aqueous methanol solutions consumed in prior direct methanol fuel-cell systems. The design concept of the proposed fuel-cell system takes advantage of (1) electro-osmotic drag and diffusion processes to manage the flows of hydrogen and water between the anode and the cathode and (2) evaporative cooling for regulating temperature. The design concept provides for supplying enough water to the anodes to enable the use of neat methanol while ensuring conservation of water for the whole fuel-cell system.

Fuel cell power plant economic and operational considerations

NASA Technical Reports Server (NTRS)

Lance, J. R.

1984-01-01

Fuel cell power plants intended for electric utility and cogeneration applications are now in the design and construction stage. This paper describes economic and operational considerations being used in the development and design of plants utilizing air cooled phosphoric acid fuel cells. Fuel cell power plants have some unique characteristics relative to other types of power plants. As a result it was necessary to develop specific definitions of the fuel cell power plant characteristics in order to perform cost of electricity calculations. This paper describes these characteristics and describes the economic analyses used in the Westinghouse fuel cell power plant program.

Development of inexpensive metal macrocyclic complexes for use in fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doddapaneni, N.; Ingersoll, D.; Kosek, J.A.

Several metal macrocyclic complexes were synthesized for use as catalysts in fuel cells. An initial evaluation of their ability to catalyze the fuel cell reactions were completed. Based on this initial evaluation, one metal macrocyclic catalyst was selected and long-term stability testing in a fuel cell was initiated. The fuel cell employing this catalyst was operated continuously for one year with little signs of catalyst degradation. The effect of synthetic reformates on the performance of the catalyst in the fuel cell environment also demonstrated high tolerance of this catalyst for common contaminants and poisons.

Hydrogen Research for Spaceport and Space-Based Applications: Fuel Cell Projects

NASA Technical Reports Server (NTRS)

Anderson, Tim; Balaban, Canan

2008-01-01

The activities presented are a broad based approach to advancing key hydrogen related technologies in areas such as fuel cells, hydrogen production, and distributed sensors for hydrogen-leak detection, laser instrumentation for hydrogen-leak detection, and cryogenic transport and storage. Presented are the results from research projects, education and outreach activities, system and trade studies. The work will aid in advancing the state-of-the-art for several critical technologies related to the implementation of a hydrogen infrastructure. Activities conducted are relevant to a number of propulsion and power systems for terrestrial, aeronautics and aerospace applications. Fuel cell research focused on proton exchange membranes (PEM), solid oxide fuel cells (SOFC). Specific technologies included aircraft fuel cell reformers, new and improved electrodes, electrolytes, interconnect, and seals, modeling of fuel cells including CFD coupled with impedance spectroscopy. Research was conducted on new materials and designs for fuel cells, along with using embedded sensors with power management electronics to improve the power density delivered by fuel cells. Fuel cell applications considered were in-space operations, aviation, and ground-based fuel cells such as; powering auxiliary power units (APUs) in aircraft; high power density, long duration power supplies for interplanetary missions (space science probes and planetary rovers); regenerative capabilities for high altitude aircraft; and power supplies for reusable launch vehicles.

Aerosol feed direct methanol fuel cell

NASA Technical Reports Server (NTRS)

Kindler, Andrew (Inventor); Narayanan, Sekharipuram R. (Inventor); Valdez, Thomas I. (Inventor)

2002-01-01

Improvements to fuel cells include introduction of the fuel as an aerosol of liquid fuel droplets suspended in a gas. The particle size of the liquid fuel droplets may be controlled for optimal fuel cell performance by selection of different aerosol generators or by separating droplets based upon size using a particle size conditioner.

Study on Improving Partial Load by Connecting Geo-thermal Heat Pump System to Fuel Cell Network

NASA Astrophysics Data System (ADS)

Obara, Shinya; Kudo, Kazuhiko

Hydrogen piping, the electric power line, and exhaust heat recovery piping of the distributed fuel cells are connected with network, and operational planning is carried out. Reduction of the efficiency in partial load is improved by operation of the geo-thermal heat pump linked to the fuel cell network. The energy demand pattern of the individual houses in Sapporo was introduced. And the analysis method aiming at minimization of the fuel rate by the genetic algorithm was described. The fuel cell network system of an analysis example assumed connecting the fuel cell co-generation of five houses. When geo-thermal heat pump was introduced into fuel cell network system stated in this paper, fuel consumption was reduced 6% rather than the conventional method

Power management systems for sediment microbial fuel cells in high power and continuous power applications

NASA Astrophysics Data System (ADS)

Donovan, Conrad Koble

The objective of this dissertation was to develop power management systems (PMS) for sediment microbial fuel cells (SFMCs) for high power and continuous applications. The first part of this dissertation covers a new method for testing the performance of SMFCs. This device called the microbial fuel cell tester was developed to automatically test power generation of PMS. The second part focuses on a PMS capable of delivering high power in burst mode. This means that for a small amount of time a large amount of power up to 2.5 Watts can be delivered from a SMFC only generating mW level power. The third part is aimed at developing a multi-potentiostat laboratory tool that measures the performance at fixed cell potentials of microbial fuel cells so that I can optimize them for use with the PMS. This tool is capable of controlling the anode potential or cathode potential and measuring current of six separate SMFCs simultaneously. By operating multiple potentiostats, I was able to run experiments that find ideal operating conditions for the sediment microbial fuel cells, and also I can optimize the power management system for these conditions. The fourth part of the dissertation is targeting a PMS that was able to operate a sensor continuously which was powered by an SMFC. In pervious applications involving SMFCs, the PMS operated in batch mode. In this PMS, the firmware on the submersible ultrasonic receiver (SUR) was modified for use with my PMS. This integration of PMS and SUR allowed for the continuous operation of the SUR without using a battery. Finally, the last part of the dissertation recommends a scale-up power management system to overcome the linearity scale up issue of SMFCs as future work. Concluding remarks are also added to summarize the goal and focus of this dissertation.

Primary and secondary electrical space power based on advanced PEM systems

NASA Technical Reports Server (NTRS)

Vanderborgh, N. E.; Hedstrom, J. C.; Stroh, K. R.; Huff, J. R.

1993-01-01

For new space ventures, power continues to be a pacing function for mission planning and experiment endurance. Although electrochemical power is a well demonstrated space power technology, current hardware limitations impact future mission viability. In order to document and augment electrochemical technology, a series of experiments for the National Aeronautics and Space Administration Lewis Research Center (NASA LeRC) are underway at the Los Alamos National Laboratory that define operational parameters on contemporary proton exchange membrane (PEM) hardware operating with hydrogen and oxygen reactants. Because of the high efficiency possible for water electrolysis, this hardware is also thought part of a secondary battery design built around stored reactants - the so-called regenerative fuel cell. An overview of stack testing at Los Alamos and of analyses related to regenerative fuel cell systems are provided in this paper. Finally, this paper describes work looking at innovative concepts that remove complexity from stack hardware with the specific intent of higher system reliability. This new concept offers the potential for unprecedented electrochemical power system energy densities.

Mass Spectrometry of Polymer Electrolyte Membrane Fuel Cells.

PubMed

Johánek, Viktor; Ostroverkh, Anna; Fiala, Roman; Rednyk, Andrii; Matolín, Vladimír

2016-01-01

The chemical analysis of processes inside fuel cells under operating conditions in either direct or inverted (electrolysis) mode and their correlation with potentiostatic measurements is a crucial part of understanding fuel cell electrochemistry. We present a relatively simple yet powerful experimental setup for online monitoring of the fuel cell exhaust (of either cathode or anode side) downstream by mass spectrometry. The influence of a variety of parameters (composition of the catalyst, fuel type or its concentration, cell temperature, level of humidification, mass flow rate, power load, cell potential, etc.) on the fuel cell operation can be easily investigated separately or in a combined fashion. We demonstrate the application of this technique on a few examples of low-temperature (70°C herein) polymer electrolyte membrane fuel cells (both alcohol- and hydrogen-fed) subjected to a wide range of conditions.

Mass Spectrometry of Polymer Electrolyte Membrane Fuel Cells

PubMed Central

Ostroverkh, Anna; Fiala, Roman; Rednyk, Andrii; Matolín, Vladimír

2016-01-01

The chemical analysis of processes inside fuel cells under operating conditions in either direct or inverted (electrolysis) mode and their correlation with potentiostatic measurements is a crucial part of understanding fuel cell electrochemistry. We present a relatively simple yet powerful experimental setup for online monitoring of the fuel cell exhaust (of either cathode or anode side) downstream by mass spectrometry. The influence of a variety of parameters (composition of the catalyst, fuel type or its concentration, cell temperature, level of humidification, mass flow rate, power load, cell potential, etc.) on the fuel cell operation can be easily investigated separately or in a combined fashion. We demonstrate the application of this technique on a few examples of low-temperature (70°C herein) polymer electrolyte membrane fuel cells (both alcohol- and hydrogen-fed) subjected to a wide range of conditions. PMID:28042492

Development Status of PEM Non-Flow-Through Fuel Cell System Technology for NASA Applications

NASA Technical Reports Server (NTRS)

Hoberecht, Mark A.; Jakupca, Ian J.

2011-01-01

Today s widespread development of proton-exchange-membrane (PEM) fuel cell technology for commercial users owes its existence to NASA, where fuel cell technology saw its first applications. Beginning with the early Gemini and Apollo programs, and continuing to this day with the Shuttle Orbiter program, fuel cells have been a primary source of electrical power for many NASA missions. This is particularly true for manned missions, where astronauts are able to make use of the by-product of the fuel cell reaction, potable water. But fuel cells also offer advantages for unmanned missions, specifically when power requirements exceed several hundred watts and primary batteries are not a viable alternative. In recent years, NASA s Exploration Technology Development Program (ETDP) funded the development of fuel cell technology for applications that provide both primary power and regenerative fuel cell energy storage for planned Exploration missions that involved a return to the moon. Under this program, the Altair Lunar Lander was a mission requiring fuel cell primary power. There were also various Lunar Surface System applications requiring regenerative fuel cell energy storage, in which a fuel cell and electrolyzer combine to form an energy storage system with hydrogen, oxygen, and water as common reactants. Examples of these systems include habitat modules and large rovers. In FY11, the ETDP has been replaced by the Enabling Technology Development and Demonstration Program (ETDDP), with many of the same technology goals and requirements applied against NASA s revised Exploration portfolio.

Fuel Cells: Status and Technical/Economic Needs

NASA Technical Reports Server (NTRS)

Rambach, Glenn

1996-01-01

The need for fuel cell and alternative fuels has become increasingly important in that the U.S. spends 1 billion dollars per week to import oil, and is expected to import 80-100 billion per year in oil by the year 2010. These imports account for half of our oil supply. If 20% of the U.S. vehicle fleet were powered by fuel cells there would be: an offset 1.1 million barrels of oil per day; and a reduction of 2 million tons per year of regulated air pollutants. Fueling fuel cells with hydrogen from reformed natural gas results in more than 90% reduction in regulated emissions, and a 70% reduction in CO2, a greenhouse gas. And fueling fuel cells with hydrogen from renewables (wind, solar geothermal, hydro) results in total elimination of all emissions. When fuel cells become commercialized: they will improve America's economic competitiveness; and the regions where they are produced will benefit economically.

Proton Exchange Membrane Fuel Cells for Electrical Power Generation On-Board Commercial Airplanes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pratt, Joesph W.; Klebanoff, Leonard E.; Munoz-Ramos, Karina

2011-05-01

Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today’s technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-didmore » the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.« less

Proton exchange membrane fuel cells for electrical power generation on-board commercial airplanes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Curgus, Dita Brigitte; Munoz-Ramos, Karina; Pratt, Joseph William

2011-05-01

Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today's technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-didmore » the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.« less

Development of a lightweight fuel cell vehicle

NASA Astrophysics Data System (ADS)

Hwang, J. J.; Wang, D. Y.; Shih, N. C.

This paper described the development of a fuel cell system and its integration into the lightweight vehicle known as the Mingdao hydrogen vehicle (MHV). The fuel cell system consists of a 5-kW proton exchange membrane fuel cell (PEMFC), a microcontroller and other supported components like a compressed hydrogen cylinder, blower, solenoid valve, pressure regulator, water pump, heat exchanger and sensors. The fuel cell not only propels the vehicle but also powers the supporting components. The MHV performs satisfactorily over a hundred-kilometer drive thus validating the concept of a fuel cell powered zero-emission vehicle. Measurements further show that the fuel cell system has an efficiency of over 30% at the power consumption for vehicle cruise, which is higher than that of a typical internal combustion engine. Tests to improve performance such as speed enhancement, acceleration and fuel efficiency will be conducted in the future work. Such tests will consist of hybridizing with a battery pack.

Fuel cell electrode interconnect contact material encapsulation and method

DOEpatents

Derose, Anthony J.; Haltiner, Jr., Karl J.; Gudyka, Russell A.; Bonadies, Joseph V.; Silvis, Thomas W.

2016-05-31

A fuel cell stack includes a plurality of fuel cell cassettes each including a fuel cell with an anode and a cathode. Each fuel cell cassette also includes an electrode interconnect adjacent to the anode or the cathode for providing electrical communication between an adjacent fuel cell cassette and the anode or the cathode. The interconnect includes a plurality of electrode interconnect protrusions defining a flow passage along the anode or the cathode for communicating oxidant or fuel to the anode or the cathode. An electrically conductive material is disposed between at least one of the electrode interconnect protrusions and the anode or the cathode in order to provide a stable electrical contact between the electrode interconnect and the anode or cathode. An encapsulating arrangement segregates the electrically conductive material from the flow passage thereby, preventing volatilization of the electrically conductive material in use of the fuel cell stack.

A direct borohydride fuel cell with a polymer fiber membrane and non-noble metal catalysts

PubMed Central

Yang, Xiaodong; Liu, Yongning; Li, Sai; Wei, Xiaozhu; Wang, Li; Chen, Yuanzhen

2012-01-01

Polymer electrolyte membranes (PEM) and Pt-based catalysts are two crucial components which determine the properties and price of fuel cells. Even though, PEM faces problem of fuel crossover in liquid fuel cells such as direct methanol fuel cell (DMFC) and direct borohydride fuel cell (DBFC), which lowers power output greatly. Here, we report a DBFC in which a polymer fiber membrane (PFM) was used, and metal oxides, such as LaNiO3 and MnO2, were used as cathode catalysts, meanwhile CoO was used as anode catalyst. Peak power density of 663 mW·cm−2 has been achieved at 65°C, which increases by a factor of 1.7–3.7 compared with classic DBFCs. This fuel cell structure can also be extended to other liquid fuel cells, such as DMFC. PMID:22880160

State of the states : fuel cells in America, 2010.

DOT National Transportation Integrated Search

2010-01-01

There is no doubt that there will be fuel cells in our future. In fact, fuel cells are here today, : available for purchase and already taking off in early markets: : Telecommunication companies are purchasing fuel cells to provide back-up or pri...

Connecticut Nutmeg Fuel Cell Bus Project : Demonstrating Advanced-Design Hybrid Fuel Cell Buses in Connecticut

DOT National Transportation Integrated Search

2011-07-01

The Federal Transit Administrations (FTA) National Fuel Cell Bus Program (NFCBP) focuses on developing commercially viable fuel cell bus technologies. The Northeast Advanced Vehicle Consortium (NAVC) is one of three non-profit consortia chosen to ...

Effect of vegetation type on treatment performance and bioelectric production of constructed wetland modules combined with microbial fuel cell (CW-MFC) treating synthetic wastewater.

PubMed

Saz, Çağdaş; Türe, Cengiz; Türker, Onur Can; Yakar, Anıl

2018-03-01

An operation of microcosm-constructed wetland modules combined with microbial fuel cell device (CW-MFC) was assessed for wastewater treatment and bioelectric generation. One of the crucial aims of the present experiment is also to determine effect of vegetation on wastewater treatment process and bioelectric production in wetland matrix with microbial fuel cell. Accordingly, CW-MFC modules with vegetation had higher treatment efficiency compared to unplanted wetland module, and average COD, NH 4 + , and TP removal efficiency in vegetated wetland modules were ranged from 85 to 88%, 95 to 97%, and 95 to 97%, respectively. However, the highest NO 3 - removal (63%) was achieved by unplanted control module during the experiment period. The maximum average output voltage, power density, and Coulombic efficiency were obtained in wetland module vegetated with Typha angustifolia for 1.01 ± 0.14 V, 7.47 ± 13.7 mWatt/m 2 , and 8.28 ± 10.4%, respectively. The results suggest that the presence of Typha angustifolia vegetation in the CW-MFC matrix provides the benefits for treatment efficiency and bioelectric production; thus, it increases microbial activities which are responsible for biodegradation of organic compounds and catalyzed to electron flow from anode to cathode. Consequently, we suggest that engineers can use vegetated wetland matrix with Typha angustifolia in CW-MFC module in order to maximize treatment efficiency and bioelectric production.

Fuel cell status -- 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirschenhofer, J.H.

1995-12-31

Fuel cells are finally coming into their own. A world that 10 years ago was unaware of the concept can now witness approximately 200 of the units in operation in 15 countries. As a result, an increasing number of utility planners and decision makers are asking how do fuel cells fit into their future. While the fuel cell concept is simple, determining which type of fuel cell to use for stationary power generation may prove taxing. Admittedly, the complexity of fuel cell development coupled with the amount of subject material and claims-versus-reality may seem overwhelming. This paper is intended tomore » provide a road map of major fuel cell development in the United States, focusing on what has been done recently and what is expected in the near future.« less

Expanded nickel screen electrical connection supports for solid oxide fuel cells

DOEpatents

Draper, Robert; Antol, Ronald F.; Zafred, Paolo R.

2002-01-01

A solid oxide fuel assembly is made, wherein rows (14, 24) of fuel cells (16, 18, 20, 26, 28, 30), each having an outer interconnection (36) and an outer electrode (32), are disposed next to each other with corrugated, electrically conducting expanded metal mesh (22) between each row of cells, the corrugated mesh (22) having top crown portions (40) and bottom shoulder portions (42), where the top crown portion (40) contacts outer interconnections (36) of the fuel cells (16, 18, 20) in a first row (14), and the bottom shoulder portions (42) contacts outer electrodes (32) of the fuel cells in a second row (24), said mesh electrically connecting each row of fuel cells, and where there are no metal felt connections between any fuel cells.

Hydrogen Fuel Cell Performance as Telecommunications Backup Power in the United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurtz, Jennifer; Saur, Genevieve; Sprik, Sam

2015-03-01

Working in collaboration with the U.S. Department of Energy (DOE) and industry project partners, the National Renewable Energy Laboratory (NREL) acts as the central data repository for the data collected from real-world operation of fuel cell backup power systems. With American Recovery and Reinvestment Act of 2009 (ARRA) co-funding awarded through DOE's Fuel Cell Technologies Office, more than 1,300 fuel cell units were deployed over a three-plus-year period in stationary, material handling equipment, auxiliary power, and backup power applications. This surpassed a Fuel Cell Technologies Office ARRA objective to spur commercialization of an early market technology by installing 1,000 fuelmore » cell units across several different applications, including backup power. By December 2013, 852 backup power units out of 1,330 fuel cell units deployed were providing backup service, mainly for telecommunications towers. For 136 of the fuel cell backup units, project participants provided detailed operational data to the National Fuel Cell Technology Evaluation Center for analysis by NREL's technology validation team. NREL analyzed operational data collected from these government co-funded demonstration projects to characterize key fuel cell backup power performance metrics, including reliability and operation trends, and to highlight the business case for using fuel cells in these early market applications. NREL's analyses include these critical metrics, along with deployment, U.S. grid outage statistics, and infrastructure operation.« less

Techno-Economic Analysis of Scalable Coal-Based Fuel Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chuang, Steven S. C.

Researchers at The University of Akron (UA) have demonstrated the technical feasibility of a laboratory coal fuel cell that can economically convert high sulfur coal into electricity with near zero negative environmental impact. Scaling up this coal fuel cell technology to the megawatt scale for the nation’s electric power supply requires two key elements: (i) developing the manufacturing technology for the components of the coal-based fuel cell, and (ii) long term testing of a kW scale fuel cell pilot plant. This project was expected to develop a scalable coal fuel cell manufacturing process through testing, demonstrating the feasibility of buildingmore » a large-scale coal fuel cell power plant. We have developed a reproducible tape casting technique for the mass production of the planner fuel cells. Low cost interconnect and cathode current collector material was identified and current collection was improved. In addition, this study has demonstrated that electrochemical oxidation of carbon can take place on the Ni anode surface and the CO and CO 2 product produced can further react with carbon to initiate the secondary reactions. One important secondary reaction is the reaction of carbon with CO 2 to produce CO. We found CO and carbon can be electrochemically oxidized simultaneously inside of the anode porous structure and on the surface of anode for producing electricity. Since CH 4 produced from coal during high temperature injection of coal into the anode chamber can cause severe deactivation of Ni-anode, we have studied how CH 4 can interact with CO 2 to produce in the anode chamber. CO produced was found able to inhibit coking and allow the rate of anode deactivation to be decreased. An injection system was developed to inject the solid carbon and coal fuels without bringing air into the anode chamber. Five planner fuel cells connected in a series configuration and tested. Extensive studies on the planner fuels and stack revealed that the planner fuel cell stack is not suitable for operation with carbon and coal fuels due to lack of mechanical strength and difficulty in sealing. We have developed scalable processes for manufacturing of process for planner and tubular cells. Our studies suggested that tubular cell stack could be the only option for scaling up the coal-based fuel cell. Although the direct feeding of coal into fuel cell can significantly simplify the fuel cell system, the durability of the fuel cell needs to be further improved before scaling up. We are developing a tubular fuel cell stack with a coal injection and a CO 2 recycling unit.« less

Lightweight Stacks of Direct Methanol Fuel Cells

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram; Valdez, Thomas

2004-01-01

An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

Catalysis in high-temperature fuel cells.

PubMed

Föger, K; Ahmed, K

2005-02-17

Catalysis plays a critical role in solid oxide fuel cell systems. The electrochemical reactions within the cell--oxygen dissociation on the cathode and electrochemical fuel combustion on the anode--are catalytic reactions. The fuels used in high-temperature fuel cells, for example, natural gas, propane, or liquid hydrocarbons, need to be preprocessed to a form suitable for conversion on the anode-sulfur removal and pre-reforming. The unconverted fuel (economic fuel utilization around 85%) is commonly combusted using a catalytic burner. Ceramic Fuel Cells Ltd. has developed anodes that in addition to having electrochemical activity also are reactive for internal steam reforming of methane. This can simplify fuel preprocessing, but its main advantage is thermal management of the fuel cell stack by endothermic heat removal. Using this approach, the objective of fuel preprocessing is to produce a methane-rich fuel stream but with all higher hydrocarbons removed. Sulfur removal can be achieved by absorption or hydro-desulfurization (HDS). Depending on the system configuration, hydrogen is also required for start-up and shutdown. Reactor operating parameters are strongly tied to fuel cell operational regimes, thus often limiting optimization of the catalytic reactors. In this paper we discuss operation of an authothermal reforming reactor for hydrogen generation for HDS and start-up/shutdown, and development of a pre-reformer for converting propane to a methane-rich fuel stream.

Investigation into the Implications of Fuel Cell Shipboard Integration into the T-AGOS 19 Class

DTIC Science & Technology

2012-02-01

with each defined by its fundamental electrolyte: i. Alkali Fuel Cells (AFC) ii. Polymer Exchange Membrane ( PEM ) iii. Phosphoric Acid Fuel Cells ...of the PEM family (High Temperature – HTPEM and Direct Methanol Fuel Cells – DMFC) were assessed against a range of basic ship requirements...of Stationary PEM Fuel Cell Systems”, DOE hydrogen program 2010 annual report. [11] US Energy Information Administration, “EIA - Weekly Retail

Space power systems technology

NASA Technical Reports Server (NTRS)

Coulman, George A.

1994-01-01

Reported here is a series of studies which examine several potential catalysts and electrodes for some fuel cell systems, some materials for space applications, and mathematical modeling and performance predictions for some solid oxide fuel cells and electrolyzers. The fuel cell systems have a potential for terrestrial applications in addition to solar energy conversion in space applications. Catalysts and electrodes for phosphoric acid fuel cell systems and for polymer electrolyte membrane (PEM) fuel cell and electrolyzer systems were examined.

Fuel from Algae in Space? NREL Helps Colorado Students with Out-of-this-World Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

An unusual project undertaken by students at Chatfield High School in Colorado might be just what America’s space program needs. The students want to see if we can create fuel from algae in space. To do so, they're sending two strains of algae supplied by the National Renewable Energy Laboratory into orbit aboard the International Space Station. Earth-bound experiments have already shown one strain produces hydrogen, which can be used to power fuel cells, while the end result for the other is a biofuel. If all goes well, these science-minded students could wind up making it easier for long-duration spacemore » voyages.« less

Defect Detection in Fuel Cell Gas Diffusion Electrodes Using Infrared Thermography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ulsh, Michael; Porter, Jason M.; Bittinat, Daniel C.

2016-04-01

Polymer electrolyte membrane fuel cells are energy conversion devices that offer high power densities and high efficiencies for mobile and other applications. Successful introduction into the marketplace requires addressing cost barriers such as production volumes and platinum loading. For cost reduction, it is vital to minimize waste and maximize quality during the manufacturing of platinum-containing electrodes, including gas diffusion electrodes (GDEs). In this work, we report on developing a quality control diagnostic for GDEs, involving creating an ex situ exothermic reaction on the electrode surface and using infrared thermography to measure the resulting temperature profile. Experiments with a moving GDEmore » containing created defects were conducted to demonstrate the applicability of the diagnostic for real-time web-line inspection.« less

Power enhancement of a μl-scale microbial fuel cells by surface roughness

NASA Astrophysics Data System (ADS)

Kim, Jihoon; Hwan Ko, Jin; Lee, Jaehyun; Jun Kim, Min; Byun, Doyoung

2014-06-01

In recent years, microbial fuel cells (MFCs) have gained much attention due to their potential to generate energy in a sustainable manner from living microorganisms. Research has shown that electrode design is a critical factor for MFCs power enhancement. In this study, we designed and fabricated MFCs energy-harvesting devices with living bacteria, and we investigated the effect of the surface roughness of the electrodes on power generation. In batch experiments of our MFCs, we found that the total power delivered could be enhanced using electrodes having rough surfaces with protruded micro-structures relative to that of electrodes with a flat surface. This was due to the delayed acidification resulting from the changes in bio-film formation between them.

Micro-Tubular Fuel Cells

NASA Technical Reports Server (NTRS)

Kimble, Michael C.; Anderson, Everett B.; Jayne, Karen D.; Woodman, Alan S.

2004-01-01

Micro-tubular fuel cells that would operate at power levels on the order of hundreds of watts or less are under development as alternatives to batteries in numerous products - portable power tools, cellular telephones, laptop computers, portable television receivers, and small robotic vehicles, to name a few examples. Micro-tubular fuel cells exploit advances in the art of proton-exchange-membrane fuel cells. The main advantage of the micro-tubular fuel cells over the plate-and-frame fuel cells would be higher power densities: Whereas the mass and volume power densities of low-pressure hydrogen-and-oxygen-fuel plate-and-frame fuel cells designed to operate in the targeted power range are typically less than 0.1 W/g and 0.1 kW/L, micro-tubular fuel cells are expected to reach power densities much greater than 1 W/g and 1 kW/L. Because of their higher power densities, micro-tubular fuel cells would be better for powering portable equipment, and would be better suited to applications in which there are requirements for modularity to simplify maintenance or to facilitate scaling to higher power levels. The development of PEMFCs has conventionally focused on producing large stacks of cells that operate at typical power levels >5 kW. The usual approach taken to developing lower-power PEMFCs for applications like those listed above has been to simply shrink the basic plate-and-frame configuration to smaller dimensions. A conventional plate-and-frame fuel cell contains a membrane/electrode assembly in the form of a flat membrane with electrodes of the same active area bonded to both faces. In order to provide reactants to both electrodes, bipolar plates that contain flow passages are placed on both electrodes. The mass and volume overhead of the bipolar plates amounts to about 75 percent of the total mass and volume of a fuel-cell stack. Removing these bipolar plates in the micro-tubular fuel cell significantly increases the power density.

Combination nickel foam expanded nickel screen electrical connection supports for solid oxide fuel cells

DOEpatents

Draper, Robert; Prevish, Thomas; Bronson, Angela; George, Raymond A.

2007-01-02

A solid oxide fuel assembly is made, wherein rows (14, 25) of fuel cells (17, 19, 21, 27, 29, 31), each having an outer interconnection (20) and an outer electrode (32), are disposed next to each other with corrugated, electrically conducting expanded metal mesh member (22) between each row of cells, the corrugated mesh (22) having top crown portions and bottom portions, where the top crown portion (40) have a top bonded open cell nickel foam (51) which contacts outer interconnections (20) of the fuel cells, said mesh and nickel foam electrically connecting each row of fuel cells, and where there are no more metal felt connections between any fuel cells.

76 FR 4645 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-26

... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Department...: This notice announces a meeting of the Hydrogen and Fuel Cell Technical Advisory Committee (HTAC). HTAC... Presentations HTAC Subcommittee Overviews HTAC Annual Report Development Stationary Fuel Cell Industry Analysis...

Regional Technical Exchange Centers Connect Fuel Cell Technology Suppliers,

Science.gov Websites

Manufacturers | News | NREL Regional Technical Exchange Centers Connect Fuel Cell Technology Suppliers, Manufacturers Regional Technical Exchange Centers Connect Fuel Cell Technology Suppliers fuel cell and hydrogen components and systems and improve U.S. manufacturing competitiveness. The

Evaluation of Fuel Cell Operation and Degradation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, Mark; Gemmen, Randall; Richards, George

The concepts of area specific resistance (ASR) and degradation are developed for different fuel cell operating modes. The concepts of exergetic efficiency and entropy production were applied to ASR and degradation. It is shown that exergetic efficiency is a time-dependent function useful describing the thermal efficiency of a fuel cell and the change in thermal efficiency of a degrading fuel cell. Entropy production was evaluated for the cases of constant voltage operation and constant current operation of the fuel cell for a fuel cell undergoing ohmic degradation. It was discovered that the Gaussian hypergeometric function describes the cumulative entropy andmore » electrical work produced by fuel cells operating at constant voltage. The Gaussian hypergeometric function is found in many applications in modern physics. This paper builds from and is an extension of several papers recently published by the authors in the Journal of The Electrochemical Society (ECS), ECS Transactions, Journal of Power Sources, and the Journal of Fuel Cell Science and Technology.« less

Characterization Testing of the Teledyne Passive Breadboard Fuel Cell Powerplant

NASA Technical Reports Server (NTRS)

Loyselle, Patricia; Prokopius, Kevin

2011-01-01

NASA's Exploration Technology Development Program (ETDP) is tasked with the development of enabling and enhancing technologies for NASA's exploration missions. As part of that initiative, the return to the Moon requires a reliable, efficient, and lightweight fuel cell powerplant system to provide power to the Altair Lunar Lander and for lunar surface systems. Fuel cell powerplants are made up of two basic parts; the fuel cell itself and the supporting ancillary subsystem. This subsystem is designed to deliver reactants to the fuel cell and remove product water and waste heat from the fuel cell. Typically, fuel cell powerplant ancillary subsystems rely upon pumps and active water separation techniques to accomplish these tasks for closed hydrogen/oxygen systems. In a typical system, these components are the largest contributors to the overall parasitic power load of the fuel cell powerplant. A potential step towards the development of an efficient lightweight power system is to maximize the use of "passive" or low-power ancillary components as a replacement to these high-power load components

Electrochemical fuel cell generator having an internal and leak tight hydrocarbon fuel reformer

DOEpatents

Dederer, J.T.; Hager, C.A.

1998-03-31

An electrochemical fuel cell generator configuration is made having a generator section which contains a plurality of axially elongated fuel cells, each cell containing a fuel electrode, air electrode, and solid oxide electrolyte between the electrodes, in which axially elongated dividers separate portions of the fuel cells from each other, and where at least one divider also reforms a reformable fuel gas mixture prior to electricity generation reactions, the at least one reformer-divider is hollow having a closed end and an open end entrance for a reformable fuel mixture to pass to the closed end of the divider and then reverse flow and pass back along the hollowed walls to be reformed, and then finally to pass as reformed fuel out of the open end of the divider to contact the fuel cells, and further where the reformer-divider is a composite structure having a gas diffusion barrier of metallic foil surrounding the external walls of the reformer-divider except at the entrance to prevent diffusion of the reformable gas mixture through the divider, and further housed in an outer insulating jacket except at the entrance to prevent short-circuiting of the fuel cells by the gas diffusion barrier. 10 figs.

Electrochemical fuel cell generator having an internal and leak tight hydrocarbon fuel reformer

DOEpatents

Dederer, Jeffrey T.; Hager, Charles A.

1998-01-01

An electrochemical fuel cell generator configuration is made having a generator section which contains a plurality of axially elongated fuel cells, each cell containing a fuel electrode, air electrode, and solid oxide electrolyte between the electrodes, in which axially elongated dividers separate portions of the fuel cells from each other, and where at least one divider also reforms a reformable fuel gas mixture prior to electricity generation reactions, the at least one reformer-divider is hollow having a closed end and an open end entrance for a reformable fuel mixture to pass to the closed end of the divider and then reverse flow and pass back along the hollowed walls to be reformed, and then finally to pass as reformed fuel out of the open end of the divider to contact the fuel cells, and further where the reformer-divider is a composite structure having a gas diffusion barrier of metallic foil surrounding the external walls of the reformer-divider except at the entrance to prevent diffusion of the reformable gas mixture through the divider, and further housed in an outer insulating jacket except at the entrance to prevent short-circuiting of the fuel cells by the gas diffusion barrier.

Performance of miniaturized direct methanol fuel cell (DMFC) devices using micropump for fuel delivery

NASA Astrophysics Data System (ADS)

Zhang, Tao; Wang, Qing-Ming

A fuel cell is a device that can convert chemical energy into electricity directly. Among various types of fuel cells, both polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs) can work at low temperature (<80 °C). Therefore, they can be used to supply power for commercial portable electronics such as laptop computers, digital cameras, PDAs and cell phones. The focus of this paper is to investigate the performance of a miniaturized DMFC device using a micropump to deliver fuel. The core of this micropump is a piezoelectric ring-type bending actuator and the associated nozzle/diffuser for directing fuel flow. Based on the experimental measurements, it is found that the performance of the fuel cell can be significantly improved if enough fuel flow is induced by the micropump at anode. Three factors may contribute to the performance enhancement including replenishment of methanol, decrease of diffusion resistance and removal of carbon dioxide. In comparison with conventional mini pumps, the size of the piezoelectric micropump is much smaller and the energy consumption is much lower. Thus, it is very viable and effective to use a piezoelectric valveless micropump for fuel delivery in miniaturized DMFC power systems.

Hugoniot and Properties of Diesel Fuel Used in ANFO

NASA Astrophysics Data System (ADS)

Robbins, David L.; Sheffield, Stephen A.; Dattelbaum, Dana M.; Stahl, David B.; Shock; Detonation Physics Team

2011-06-01

One of the more common ammonium nitrate (AN) based explosive is called ANFO, which is a mixture of AN prills and diesel fuel oil (FO) in a 94:6 ratio by weight. Since there is no available shock data on FO, a series of shock compression experiments have been completed on a two-stage light gas gun with a sealed liquid target cell. We have chosen a representative grade of fuel oil (diesel) for our experiments. Knowing that all FO is not the same, we decided to study this material, assuming it is representative. Density and sound speed data were measured, and used to predict the unreacted Hugoniot. The data were found to compare well with a universal liquid Hugoniot. In-situ magnetic gauges in the target cell were used to measure the particle velocity, shock velocity, and shock wave profiles. Impact velocities ranged from 1.5 to 3.2 km/s generating shocked pressures between 3 and 17 GPa, depending on the impactor material being used. The FO Hugoniot is being used in conjunction with ongoing ammonium nitrate (AN) shock compression measurements to further understand the unreacted Hugoniot of the ANFO mixture. Additionally, wave profiles and the Hugoniot are analyzed to determine if shock-induced reaction occurs, within the pressure range studied.

Modeling cascading diffusion of new energy technologies: case study of residential solid oxide fuel cells in the US and internationally.

PubMed

Herron, Seth; Williams, Eric

2013-08-06

Subsidy programs for new energy technologies are motivated by the experience curve: increased adoption of a technology leads to learning and economies of scale that lower costs. Geographic differences in fuel prices and climate lead to large variability in the economic performance of energy technologies. The notion of cascading diffusion is that regions with favorable economic conditions serve as the basis to build scale and reduce costs so that the technology becomes attractive in new regions. We develop a model of cascading diffusion and implement via a case study of residential solid oxide fuel cells (SOFCs) for combined heating and power. We consider diffusion paths within the U.S. and internationally. We construct market willingness-to-pay curves and estimate future manufacturing costs via an experience curve. Combining market and cost results, we find that for rapid cost reductions (learning rate = 25%), a modest public subsidy can make SOFC investment profitable for 20-160 million households. If cost reductions are slow however (learning rate = 15%), residential SOFCs may not become economically competitive. Due to higher energy prices in some countries, international diffusion is more favorable than domestic, mitigating much of the uncertainty in the learning rate.

Heat exchanger for fuel cell power plant reformer

DOEpatents

Misage, Robert; Scheffler, Glenn W.; Setzer, Herbert J.; Margiott, Paul R.; Parenti, Jr., Edmund K.

1988-01-01

A heat exchanger uses the heat from processed fuel gas from a reformer for a fuel cell to superheat steam, to preheat raw fuel prior to entering the reformer and to heat a water-steam coolant mixture from the fuel cells. The processed fuel gas temperature is thus lowered to a level useful in the fuel cell reaction. The four temperature adjustments are accomplished in a single heat exchanger with only three heat transfer cores. The heat exchanger is preheated by circulating coolant and purge steam from the power section during startup of the latter.

Solid oxide fuel cell simulation and design optimization with numerical adjoint techniques

NASA Astrophysics Data System (ADS)

Elliott, Louie C.

This dissertation reports on the application of numerical optimization techniques as applied to fuel cell simulation and design. Due to the "multi-physics" inherent in a fuel cell, which results in a highly coupled and non-linear behavior, an experimental program to analyze and improve the performance of fuel cells is extremely difficult. This program applies new optimization techniques with computational methods from the field of aerospace engineering to the fuel cell design problem. After an overview of fuel cell history, importance, and classification, a mathematical model of solid oxide fuel cells (SOFC) is presented. The governing equations are discretized and solved with computational fluid dynamics (CFD) techniques including unstructured meshes, non-linear solution methods, numerical derivatives with complex variables, and sensitivity analysis with adjoint methods. Following the validation of the fuel cell model in 2-D and 3-D, the results of the sensitivity analysis are presented. The sensitivity derivative for a cost function with respect to a design variable is found with three increasingly sophisticated techniques: finite difference, direct differentiation, and adjoint. A design cycle is performed using a simple optimization method to improve the value of the implemented cost function. The results from this program could improve fuel cell performance and lessen the world's dependence on fossil fuels.

Fuel cell development for transportation: Catalyst development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doddapaneni, N.

1996-04-01

Fuel cells are being considered as alternate power sources for transportation and stationary applications. With proton exchange membrane (PEM) fuel cells the fuel crossover to cathodes causes severe thermal management and cell voltage drop due to oxidation of fuel at the platinized cathodes. The main goal of this project was to design, synthesize, and evaluate stable and inexpensive transition metal macrocyclic catalysts for the reduction of oxygen and be electrochemically inert towards anode fuels such as hydrogen and methanol.

Estimation of electrode ionomer oxygen permeability and ionomer-phase oxygen transport resistance in polymer electrolyte fuel cells.

PubMed

Sambandam, Satheesh; Parrondo, Javier; Ramani, Vijay

2013-09-28

The oxygen permeability of perfluorinated and hydrocarbon polymer electrolyte membranes (PEMs; Nafion®, SPEEK and SPSU), which are used as electrolytes and electrode ionomers in polymer electrolyte fuel cells (PEFCs), was estimated using chronoamperometry using a modified fuel cell set-up. A thin, cylindrical microelectrode was embedded into the PEM and used as the working electrode. The PEM was sandwiched between 2 gas diffusion electrodes, one of which was catalyzed and served as the counter and pseudo-reference electrode. Independently, from fuel cell experiments, the oxygen transport resistance arising due to transport through the ionomer film covering the catalyst active sites was estimated at the limiting current and decoupled from the overall mass transport resistance. The in situ oxygen permeability measured at 80 °C and 75% RH of perfluorinated ionomers such as Nafion® (3.85 × 10(12) mol cm(-1) s(-1)) was observed to be an order of magnitude higher than that of hydrocarbon-based PEMs such as SPEEK (0.27 × 10(12) mol cm(-1) s(-1)) and SPSU (0.15 × 10(12) mol cm(-1) s(-1)). The obtained oxygen transport (through ionomer film) resistance values (Nafion® - 1.6 s cm(-1), SPEEK - 2.2 s cm(-1) and SPSU - 3.0 s cm(-1); at 80 °C and 75% RH) correlated well with the measured oxygen permeabilities in these ion-containing polymers.

A direct ascorbate fuel cell with an anion exchange membrane

NASA Astrophysics Data System (ADS)

Muneeb, Omar; Do, Emily; Tran, Timothy; Boyd, Desiree; Huynh, Michelle; Ghosn, Gregory; Haan, John L.

2017-05-01

Ascorbic Acid (Vitamin C) is investigated as a renewable alternative fuel for alkaline direct liquid fuel cells (DLFCs). The environmentally- and biologically-friendly compound, L-ascorbic acid (AA) has been modeled and studied experimentally under acidic fuel cell conditions. In this work, we demonstrate that ascorbic acid is a more efficient fuel in alkaline media than in acidic media. An operating direct ascorbate fuel cell is constructed with the combination of L-ascorbic acid and KOH as the anode fuel, air or oxygen as the oxidant, a polymer anion exchange membrane, metal or carbon black anode materials and metal cathode catalyst. Operation of the fuel cell at 60 °C using 1 M AA and 1 M KOH as the anode fuel and electrolyte, respectively, and oxygen gas at the cathode, produces a maximum power density of 73 mW cm-2, maximum current density of 497 mA cm-2 and an open circuit voltage of 0.90 V. This performance is significantly greater than that of an ascorbic acid fuel cell with a cation exchange membrane, and it is competitive with alkaline DLFCs fueled by alcohols.

Fuel economy of hybrid fuel-cell vehicles

NASA Astrophysics Data System (ADS)

Ahluwalia, Rajesh K.; Wang, X.; Rousseau, A.

The potential improvement in fuel economy of a mid-size fuel-cell vehicle by combining it with an energy storage system has been assessed. An energy management strategy is developed and used to operate the direct hydrogen, pressurized fuel-cell system in a load-following mode and the energy storage system in a charge-sustaining mode. The strategy places highest priority on maintaining the energy storage system in a state where it can supply unanticipated boost power when the fuel-cell system alone cannot meet the power demand. It is found that downsizing a fuel-cell system decreases its efficiency on a drive cycle which is compensated by partial regenerative capture of braking energy. On a highway cycle with limited braking energy the increase in fuel economy with hybridization is small but on the stop-and-go urban cycle the fuel economy can improve by 27%. On the combined highway and urban drive cycles the fuel economy of the fuel-cell vehicle is estimated to increase by up to 15% by hybridizing it with an energy storage system.

Hydrogen storage with trilithium aluminum hexahydride

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nathaniel, T.A.

1998-05-14

Fuel cells have good potential to replace batteries for many applications requiring moderate, portable electric power. Applications being researched can range from cellular telephones and radios to power generators for large camps. The primary advantages of fuel cells include high power density, low temperature operation, silent operation, no poisonous exhausts, high electric efficiency, and fast start-up capability. While many commercial industries are just beginning to look at the opportunities fuel cells present, the space program has driven the development of fuel cell technology. The paper discusses the status of the fuel cell and in particular, the technology for hydrogen storagemore » for fuel cell use.« less

Fuel cell system for transportation applications

DOEpatents

Kumar, Romesh; Ahmed, Shabbir; Krumpelt, Michael; Myles, Kevin M.

1993-01-01

A propulsion system for a vehicle having pairs of front and rear wheels and a fuel tank. An electrically driven motor having an output shaft operatively connected to at least one of said pair of wheels is connected to a fuel cell having a positive electrode and a negative electrode separated by an electrolyte for producing dc power to operate the motor. A partial oxidation reformer is connected both to the fuel tank and to the fuel cell receives hydrogen-containing fuel from the fuel tank and water and air and for partially oxidizing and reforming the fuel with water and air in the presence of an oxidizing catalyst and a reforming catalyst to produce a hydrogen-containing gas. The hydrogen-containing gas is sent from the partial oxidation reformer to the fuel cell negative electrode while air is transported to the fuel cell positive electrode to produce dc power for operating the electric motor.

Fuel cell system for transportation applications

DOEpatents

Kumar, R.; Ahmed, S.; Krumpelt, M.; Myles, K.M.

1993-09-28

A propulsion system is described for a vehicle having pairs of front and rear wheels and a fuel tank. An electrically driven motor having an output shaft operatively connected to at least one of said pair of wheels is connected to a fuel cell having a positive electrode and a negative electrode separated by an electrolyte for producing dc power to operate the motor. A partial oxidation reformer is connected both to the fuel tank and to the fuel cell and receives hydrogen-containing fuel from the fuel tank and uses water and air for partially oxidizing and reforming the fuel in the presence of an oxidizing catalyst and a reforming catalyst to produce a hydrogen-containing gas. The hydrogen-containing gas is sent from the partial oxidation reformer to the fuel cell negative electrode while air is transported to the fuel cell positive electrode to produce dc power for operating the electric motor. 3 figures.

Modeling, analysis and control of fuel cell hybrid power systems

NASA Astrophysics Data System (ADS)

Suh, Kyung Won

Transient performance is a key characteristic of fuel cells, that is sometimes more critical than efficiency, due to the importance of accepting unpredictable electric loads. To fulfill the transient requirement in vehicle propulsion and portable fuel cell applications, a fuel cell stack is typically coupled with a battery through a DC/DC converter to form a hybrid power system. Although many power management strategies already exist, they all rely on low level controllers that realize the power split. In this dissertation we design controllers that realize various power split strategies by directly manipulating physical actuators (low level commands). We maintain the causality of the electric dynamics (voltage and current) and investigate how the electric architecture affects the hybridization level and the power management. We first establish the performance limitations associated with a stand-alone and power-autonomous fuel cell system that is not supplemented by an additional energy storage and powers all its auxiliary components by itself. Specifically, we examine the transient performance in fuel cell power delivery as it is limited by the air supplied by a compressor driven by the fuel cell itself. The performance limitations arise from the intrinsic coupling in the fluid and electrical domain between the compressor and the fuel cell stack. Feedforward and feedback control strategies are used to demonstrate these limitations analytically and with simulations. Experimental tests on a small commercial fuel cell auxiliary power unit (APU) confirm the dynamics and the identified limitations. The dynamics associated with the integration of a fuel cell system and a DC/DC converter is then investigated. Decentralized and fully centralized (using linear quadratic techniques) controllers are designed to regulate the power system voltage and to prevent fuel cell oxygen starvation. Regulating these two performance variables is a difficult task and requires a compromise due to the conflicting objectives. The compromise can be mitigated by augmenting the fuel cell power system with an energy buffer such as a battery. We consider two different and popular ways of connecting the battery and the fuel cell to the load and we refer to them as electric architectures. Various controller gains are used to span the fuel cell operation from load-following to load-leveling, and hence, to determine adequate fuel cell-battery sizing (hybridization level) and the associated trends in the system efficiency.

DOE perspective on fuel cells in transportation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kost, R.

1996-04-01

Fuel cells are one of the most promising technologies for meeting the rapidly growing demand for transportation services while minimizing adverse energy and environmental impacts. This paper reviews the benefits of introducing fuel cells into the transportation sector; in addition to dramatically reduced vehicle emissions, fuel cells offer the flexibility than use petroleum-based or alternative fuels, have significantly greater energy efficiency than internal combustion engines, and greatly reduce noise levels during operation. The rationale leading to the emphasis on proton-exchange-membrane fuel cells for transportation applications is reviewed as are the development issues requiring resolution to achieve adequate performance, packaging, andmore » cost for use in automobiles. Technical targets for power density, specific power, platinum loading on the electrodes, cost, and other factors that become increasingly more demanding over time have been established. Fuel choice issues and pathways to reduced costs and to a renewable energy future are explored. One such path initially introduces fuel cell vehicles using reformed gasoline while-on-board hydrogen storage technology is developed to the point of allowing adequate range (350 miles) and refueling convenience. This scenario also allows time for renewable hydrogen production technologies and the required supply infrastructure to develop. Finally, the DOE Fuel Cells in Transportation program is described. The program, whose goal is to establish the technology for fuel cell vehicles as rapidly as possible, is being implemented by means of the United States Fuel Cell Alliance, a Government-industry alliance that includes Detroit`s Big Three automakers, fuel cell and other component suppliers, the national laboratories, and universities.« less

Properties and degradation of the gasket component of a proton exchange membrane fuel cell--a review.

PubMed

Basuli, Utpal; Jose, Jobin; Lee, Ran Hee; Yoo, Yong Hwan; Jeong, Kwang-Un; Ahn, Jou-Hyeon; Nah, Changwoon

2012-10-01

Proton exchange membrane (PEM) fuel cell stack requires gaskets and seals in each cell to keep the reactant gases within their respective regions. Gasket performance is integral to the successful long-term operation of a fuel cell stack. This review focuses on properties, performance and degradation mechanisms of the different polymer gasket materials used in PEM fuel cell under normal operating conditions. The different degradation mechanisms and their corresponding representative mitigation strategies are also presented here. Summary of various properties of elastomers and their advantages and disadvantages in fuel cell'environment are presented. By considering the level of chemical degradation, mechanical properties and cost effectiveness, it can be proposed that EPDM is one of the best choices for gasket material in PEM fuel cell. Finally, the challenges that remain in using rubber component as in PEM fuel cell, as well as the prospects for exploiting them in the future are discussed.

A comparison of sodium borohydride as a fuel for proton exchange membrane fuel cells and for direct borohydride fuel cells

NASA Astrophysics Data System (ADS)

Wee, Jung-Ho

Two types of fuel cell systems using NaBH 4 aqueous solution as a fuel are possible: the hydrogen/air proton exchange membrane fuel cell (PEMFC) which uses onsite H 2 generated via the NaBH 4 hydrolysis reaction (B-PEMFC) at the anode and the direct borohydride fuel cell (DBFC) system which directly uses NaBH 4 aqueous solution at the anode and air at the cathode. Recently, research on these two types of fuel cells has begun to attract interest due to the various benefits of this liquid fuel for fuel cell systems for portable applications. It might therefore be relevant at this stage to evaluate the relative competitiveness of the two fuel cells. Considering their current technologies and the high price of NaBH 4, this paper evaluated and analyzed the factors influencing the relative favorability of each type of fuel cell. Their relative competitiveness was strongly dependent on the extent of the NaBH 4 crossover. When considering the crossover in DBFC systems, the total costs of the B-PEMFC system were the most competitive among the fuel cell systems. On the other hand, if the crossover problem were to be completely overcome, the total cost of the DBFC system generating six electrons (6e-DBFC) would be very similar to that of the B-PEMFC system. The DBFC system generating eight electrons (8e-DBFC) became even more competitive if the problem of crossover can be overcome. However, in this case, the volume of NaBH 4 aqueous solution consumed by the DBFC was larger than that consumed by the B-PEMFC.

Fuel cell elements with improved water handling capacity

NASA Technical Reports Server (NTRS)

Kindler, Andrew (Inventor); Lee, Albany (Inventor)

2001-01-01

New fuel cell components for use in liquid feed fuel cell systems are provided. The components include biplates and endplates, having a hydrophilic surface and allow high efficiency operation. Conductive elements and a wicking device also form a part of the fuel cell components of the invention.

77 FR 65542 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-29

... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Hydrogen and Fuel Cell... Energy. ACTION: Notice of Open Meeting. SUMMARY: The Hydrogen and Fuel Cell Technical Advisory Committee... Updates Congressional Fuel Cell Caucuses NREL Reports on Hydrogen in Natural Gas Pipelines and...

76 FR 60478 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-29

... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Department...: The Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) was established under section 807 of... Gas Supply on Fuel Cell and Hydrogen Market. Industry Presentations. Status Cost and Performance of...

Biodegradation of diesel/biodiesel blends by a consortium of hydrocarbon degraders: effect of the type of blend and the addition of biosurfactants.

PubMed

Owsianiak, Mikołaj; Chrzanowski, Łukasz; Szulc, Alicja; Staniewski, Jacek; Olszanowski, Andrzej; Olejnik-Schmidt, Agnieszka K; Heipieper, Hermann J

2009-02-01

Biodegradation experiments for diesel/biodiesel blends in liquid cultures by-petroleum degrading microbial consortium showed that for low amendments of biodiesel (10%) the overall biodegradation efficiency of the mixture after seven days was lower than for petroleum diesel fuel. Preferential usage of methyl esters in the broad biodiesel concentration range and diminished biodegradation of petroleum hydrocarbons for 10% biodiesel blend was confirmed. Rhamnolipids improved biodegradation efficiency only for blends with low content of biodiesel. Emulsion formation experiments showed that biodiesel amendments significantly affected dispersion of fuel mixtures in water. The presence of rhamnolipids biosurfactant affected stability of such emulsions and altered cell surface properties of tested consortium.

Bench-Scale Monolith Autothermal Reformer Catalyst Screening Evaluations in a Micro-Reactor With Jet-A Fuel

NASA Technical Reports Server (NTRS)

Tomsik, Thomas M.; Yen, Judy C.H.; Budge, John R.

2006-01-01

Solid oxide fuel cell systems used in the aerospace or commercial aviation environment require a compact, light-weight and highly durable catalytic fuel processor. The fuel processing method considered here is an autothermal reforming (ATR) step. The ATR converts Jet-A fuel by a reaction with steam and air forming hydrogen (H2) and carbon monoxide (CO) to be used for production of electrical power in the fuel cell. This paper addresses the first phase of an experimental catalyst screening study, looking at the relative effectiveness of several monolith catalyst types when operating with untreated Jet-A fuel. Six monolith catalyst materials were selected for preliminary evaluation and experimental bench-scale screening in a small 0.05 kWe micro-reactor test apparatus. These tests were conducted to assess relative catalyst performance under atmospheric pressure ATR conditions and processing Jet-A fuel at a steam-to-carbon ratio of 3.5, a value higher than anticipated to be run in an optimized system. The average reformer efficiencies for the six catalysts tested ranged from 75 to 83 percent at a constant gas-hourly space velocity of 12,000 hr 1. The corresponding hydrocarbon conversion efficiency varied from 86 to 95 percent during experiments run at reaction temperatures between 750 to 830 C. Based on the results of the short-duration 100 hr tests reported herein, two of the highest performing catalysts were selected for further evaluation in a follow-on 1000 hr life durability study in Phase II.

Analytic Methods for Benchmarking Hydrogen and Fuel Cell Technologies; NREL (National Renewable Energy Laboratory)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melaina, Marc; Saur, Genevieve; Ramsden, Todd

2015-05-28

This presentation summarizes NREL's hydrogen and fuel cell analysis work in three areas: resource potential, greenhouse gas emissions and cost of delivered energy, and influence of auxiliary revenue streams. NREL's hydrogen and fuel cell analysis projects focus on low-­carbon and economic transportation and stationary fuel cell applications. Analysis tools developed by the lab provide insight into the degree to which bridging markets can strengthen the business case for fuel cell applications.

Conceptual Design Tool for Fuel-Cell Powered Micro Air Vehicles

DTIC Science & Technology

2010-03-01

Electrolyte Membrane PEMFC PEM Fuel Cell RAM Rapid Aircraft Modeler R/C Radio Controlled RMFC Reformed Methanol Fuel Cell SBIR Small Business...of rechargeable batteries, the Proton Exchange Membrane Fuel Cell ( PEMFC ) is only limited by the amount of hydrogen it can store, and can be...of fuel cells within MAVs through the creation of the Hornet. This slightly heavier, 380 g MAV integrated a 10 W PEMFC into the wing surface for a

Investigation into the Implications of Fuel Cell Shipboard Integration into the T-AGOS 19 Class

DTIC Science & Technology

2012-02-01

with each defined by its fundamental electrolyte: i. Alkali Fuel Cells (AFC) ii. Polymer Exchange Membrane ( PEM ) iii. Phosphoric Acid Fuel Cells ...of the PEM family (High Temperature – HTPEM and Direct Methanol Fuel Cells – DMFC) were assessed against a range of basic ship requirements...of fuel cell stacks in 100+kW power range for realistic marine applications, two technologies can be quickly discounted, namely – AFC, DMFC. PEM

Effect of Lanthanum-Strontium Cathode Current-Collecting Layer on the Performance of Anode Supported Type Planar Solid Oxide Fuel Cells

NASA Astrophysics Data System (ADS)

Park, Sun-Young; Ji, Ho-Il; Kim, Hae-Ryoung; Yoon, Kyung Joong; Son, Ji-Won; Lee, Hae-Weon; Lee, Jong-Ho

2013-07-01

We applied screen-printed (La,Sr)CoO3 as a current-collecting layer of planar type unit-cell for lower temperature operation of SOFCs. In this study the effects of the cathode current-collecting layer on the performance of unit cell and symmetric half cell were investigated via AC and DC polarization experiments. According to our investigation, appropriately controlled current collecting layer was very effective to enhance the unit cell performance by reducing not only the ohmic resistance but also the polarization losses of SOFC cathode.

Final Report - Stationary and Emerging Market Fuel Cell System Cost Assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Contini, Vince; Heinrichs, Mike; George, Paul

The U.S. Department of Energy (DOE) is focused on providing a portfolio of technology solutions to meet energy security challenges of the future. Fuel cells are a part of this portfolio of technology offerings. To help meet these challenges and supplement the understanding of the current research, Battelle has executed a five-year program that evaluated the total system costs and total ownership costs of two technologies: (1) an ~80 °C polymer electrolyte membrane fuel cell (PEMFC) technology and (2) a solid oxide fuel cell (SOFC) technology, operating with hydrogen or reformate for different applications. Previous research conducted by Battelle, andmore » more recently by other research institutes, suggests that fuel cells can offer customers significant fuel and emission savings along with other benefits compared to incumbent alternatives. For this project, Battelle has applied a proven cost assessment approach to assist the DOE Fuel Cell Technologies Program in making decisions regarding research and development, scale-up, and deployment of fuel cell technology. The cost studies and subsequent reports provide accurate projections of current system costs and the cost impact of state-of-the-art technologies in manufacturing, increases in production volume, and changes to system design on system cost and life cycle cost for several near-term and emerging fuel cell markets. The studies also provide information on types of manufacturing processes that must be developed to commercialize fuel cells and also provide insights into the optimization needed for use of off-the-shelf components in fuel cell systems. Battelle’s analysis is intended to help DOE prioritize investments in research and development of components to reduce the costs of fuel cell systems while considering systems optimization.« less

Scott Mauger | NREL

Science.gov Websites

into fuel cell electrodes. He also has extensive experience researching solution-processed organic , 2016, Honolulu, HI. MA2016-02 2447 "Doped interlayers for improved selectivity in organic . Boé, D.P. Ostrowski, D.C. Olson, S.R. Hammond, Organic Electronics, 2016, 31: 63-70. "Printed

Solid oxide MEMS-based fuel cells

DOEpatents

Jankowksi, Alan F.; Morse, Jeffrey D.

2007-03-13

A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. The electrolyte layer can consist of either a solid oxide or solid polymer material, or proton exchange membrane electrolyte materials may be used. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

Solid polymer MEMS-based fuel cells

DOEpatents

Jankowski, Alan F [Livermore, CA; Morse, Jeffrey D [Pleasant Hill, CA

2008-04-22

A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. The electrolyte layer can consist of either a solid oxide or solid polymer material, or proton exchange membrane electrolyte materials may be used. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

Proton exchange membrane fuel cell system diagnosis based on the signed directed graph method

NASA Astrophysics Data System (ADS)

Hua, Jianfeng; Lu, Languang; Ouyang, Minggao; Li, Jianqiu; Xu, Liangfei

The fuel-cell powered bus is becoming the favored choice for electric vehicles because of its extended driving range, zero emissions, and high energy conversion efficiency when compared with battery-operated electric vehicles. In China, a demonstration program for the fuel cell bus fleet operated at the Beijing Olympics in 2008 and the Shanghai Expo in 2010. It is necessary to develop comprehensive proton exchange membrane fuel cell (PEMFC) diagnostic tools to increase the reliability of these systems. It is especially critical for fuel-cell city buses serving large numbers of passengers using public transportation. This paper presents a diagnostic analysis and implementation study based on the signed directed graph (SDG) method for the fuel-cell system. This diagnostic system was successfully implemented in the fuel-cell bus fleet at the Shanghai Expo in 2010.

Transport phenomena in alkaline direct ethanol fuel cells for sustainable energy production

NASA Astrophysics Data System (ADS)

An, L.; Zhao, T. S.

2017-02-01

Alkaline direct ethanol fuel cells (DEFC), which convert the chemical energy stored in ethanol directly into electricity, are one of the most promising energy-conversion devices for portable, mobile and stationary power applications, primarily because this type of fuel cell runs on a carbon-neutral, sustainable fuel and the electrocatalytic and membrane materials that constitute the cell are relatively inexpensive. As a result, the alkaline DEFC technology has undergone a rapid progress over the last decade. This article provides a comprehensive review of transport phenomena of various species in this fuel cell system. The past investigations into how the design and structural parameters of membrane electrode assemblies and the operating parameters affect the fuel cell performance are discussed. In addition, future perspectives and challenges with regard to transport phenomena in this fuel cell system are also highlighted.

Direct hydrocarbon fuel cells

DOEpatents

Barnett, Scott A.; Lai, Tammy; Liu, Jiang

2010-05-04

The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

Integrated Fuel Cell/Coal Gasifier

NASA Technical Reports Server (NTRS)

Ferrall, J. F.

1985-01-01

Powerplant design with low-temperature coal gasifier coupled to highly-exothermic fuel cell for efficient production of dc power eliminates need for oxygen in gasifier and achieves high fuel efficiency with recycling of waste heat from fuel cell.

Catalysts compositions for use in fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chuang, Steven S.C.

2015-12-01

The present invention generally relates to the generation of electrical energy from a solid-state fuel. In one embodiment, the present invention relates to a solid-oxide fuel cell for generating electrical energy from a carbon-based fuel, and to catalysts for use in a solid-oxide fuel cell.

Bringing fuel cell vehicles to market : scenarios and challenges with fuel alternatives : consultant study report [version 1.1

DOT National Transportation Integrated Search

2001-10-01

The California Fuel Cell Partnership (CaFCP) commissioned a study on bringing fuel cell vehicles to market and the scenarios and challenges with fuel alternatives. The study's overall goal was to identify challenges and solutions for four different f...

Three-wheel air turbocompressor for PEM fuel cell systems

DOEpatents

Rehg, Tim; Gee, Mark; Emerson, Terence P.; Ferrall, Joe; Sokolov, Pavel

2003-08-19

A fuel cell system comprises a compressor and a fuel processor downstream of the compressor. A fuel cell stack is in communication with the fuel processor and compressor. A combustor is downstream of the fuel cell stack. First and second turbines are downstream of the fuel processor and in parallel flow communication with one another. A distribution valve is in communication with the first and second turbines. The first and second turbines are mechanically engaged to the compressor. A bypass valve is intermediate the compressor and the second turbine, with the bypass valve enabling a compressed gas from the compressor to bypass the fuel processor.

Advances in fuel cell vehicle design

NASA Astrophysics Data System (ADS)

Bauman, Jennifer

Factors such as global warming, dwindling fossil fuel reserves, and energy security concerns combine to indicate that a replacement for the internal combustion engine (ICE) vehicle is needed. Fuel cell vehicles have the potential to address the problems surrounding the ICE vehicle without imposing any significant restrictions on vehicle performance, driving range, or refuelling time. Though there are currently some obstacles to overcome before attaining the widespread commercialization of fuel cell vehicles, such as improvements in fuel cell and battery durability, development of a hydrogen infrastructure, and reduction of high costs, the fundamental concept of the fuel cell vehicle is strong: it is efficient, emits zero harmful emissions, and the hydrogen fuel can be produced from various renewable sources. Therefore, research on fuel cell vehicle design is imperative in order to improve vehicle performance and durability, increase efficiency, and reduce costs. This thesis makes a number of key contributions to the advancement of fuel cell vehicle design within two main research areas: powertrain design and DC/DC converters. With regards to powertrain design, this research first analyzes various powertrain topologies and energy storage system types. Then, a novel fuel cell-battery-ultracapacitor topology is presented which shows reduced mass and cost, and increased efficiency, over other promising topologies found in the literature. A detailed vehicle simulator is created in MATLAB/Simulink in order to simulate and compare the novel topology with other fuel cell vehicle powertrain options. A parametric study is performed to optimize each powertrain and general conclusions for optimal topologies, as well as component types and sizes, for fuel cell vehicles are presented. Next, an analytical method to optimize the novel battery-ultracapacitor energy storage system based on maximizing efficiency, and minimizing cost and mass, is developed. This method can be applied to any system utilizing the novel battery-ultracapacitor energy storage system and is not limited in application to only fuel cell vehicles. With regards to DC/DC converters, it is important to design efficient and light-weight converters for use in fuel cell and other electric vehicles to improve overall vehicle fuel economy. Thus, this research presents a novel soft-switching method, the capacitor-switched regenerative snubber, for the high-power DC/DC boost converters commonly used in fuel cell vehicles. This circuit is shown to increase the efficiency and reduce the overall mass of the DC/DC boost converter.

A Novel Unitized Regenerative Proton Exchange Membrane Fuel Cell

NASA Technical Reports Server (NTRS)

Murphy, O. J.; Cisar, A. J.; Gonzalez-Martin, A.; Salinas, C. E.; Simpson, S. F.

1996-01-01

A difficulty encountered in designing a unitized regenerative proton exchange membrane (PEM) fuel cell lies in the incompatibility of electrode structures and electrocatalyst materials optimized for either of the two functions (fuel cell or electrolyzer) with the needs of the other function. This difficulty is compounded in previous regenerative fuel cell designs by the fact that water, which is needed for proton conduction in the PEM during both modes of operation, is the reactant supplied to the anode in the electrolyzer mode of operation and the product formed at the cathode in the fuel cell mode. Drawbacks associated with existing regenerative fuel cells have been addressed. In a first innovation, electrodes function either as oxidation electrodes (hydrogen ionization or oxygen evolution) or as reduction electrodes (oxygen reduction or hydrogen evolution) in the fuel cell and electrolyzer modes, respectively. Control of liquid water within the regenerative fuel cell has been brought about by a second innovation. A novel PEM has been developed with internal channels that permit the direct access of water along the length of the membrane. Lateral diffusion of water along the polymer chains of the PEM provides the water needed at electrode/PEM interfaces. Fabrication of the novel single cell unitized regenerative fuel cell and results obtained on testing it are presented.

Fuel cell energy storage for Space Station enhancement

NASA Technical Reports Server (NTRS)

Stedman, J. K.

1990-01-01

Viewgraphs on fuel cell energy storage for space station enhancement are presented. Topics covered include: power profile; solar dynamic power system; photovoltaic battery; space station energy demands; orbiter fuel cell power plant; space station energy storage; fuel cell system modularity; energy storage system development; and survival power supply.

Chemical compositions, methods of making the chemical compositions, and structures made from the chemical compositions

DOEpatents

Yang, Lei; Cheng, Zhe; Liu, Ze; Liu, Meilin

2015-01-13

Embodiments of the present disclosure include chemical compositions, structures, anodes, cathodes, electrolytes for solid oxide fuel cells, solid oxide fuel cells, fuel cells, fuel cell membranes, separation membranes, catalytic membranes, sensors, coatings for electrolytes, electrodes, membranes, and catalysts, and the like, are disclosed.

USING LANDFILL GAS IN FUEL CELLS - A STEP CLOSER TO COMMERICAL REALITY

EPA Science Inventory

The article discusses Phase II and Phase III results of a U.S. EPA program underway at International Fuel Cells Corporation. The program involves controlling methane emissions from landfills using a fuel cell. The fuel cell would reduce air emissions affecting global warming, aci...

Simplified Load-Following Control for a Fuel Cell System

NASA Technical Reports Server (NTRS)

Vasquez, Arturo

2010-01-01

A simplified load-following control scheme has been proposed for a fuel cell power system. The scheme could be used to control devices that are important parts of a fuel cell system but are sometimes characterized as parasitic because they consume some of the power generated by the fuel cells.

SEWAGE OFF-GAS-DRIVEN FUEL CELLS TO STIMULATE RURAL ELECTRIFICATION

EPA Science Inventory

Literature reviews confirmed the feasibility of the system relying on methane to supply the fuel cell and the waste heat from the subsequent fuel cell operation driving the decomposition process. A batch bioreactor and a proton exchange fuel cell at the lab scale are used to c...

Creep resistant, metal-coated LiFeO.sub.2 anodes for molten carbonated fuel cells

DOEpatents

Khandkar, Ashok C.

1994-01-01

A porous, creep-resistant, metal-coated, LiFeO.sub.2 ceramic electrode for fuel cells is disclosed. The electrode is particularly useful for molten carbonate fuel cells (MCFC) although it may have utilities in solid oxide fuel cells (SOFC) as well.

Creep resistant, metal-coated LiFeO[sub 2] anodes for molten carbonated fuel cells

DOEpatents

Khandkar, A.C.

1994-08-23

A porous, creep-resistant, metal-coated, LiFeO[sub 2] ceramic electrode for fuel cells is disclosed. The electrode is particularly useful for molten carbonate fuel cells (MCFC) although it may have utilities in solid oxide fuel cells (SOFC) as well. 11 figs.

78 FR 60866 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-02

... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Office of...: This notice announces an open meeting of the Hydrogen and Fuel Cell Technical Advisory Committee (HTAC... Committee: The Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) was established under section 807...

Fuel Cells: A Real Option for Unmanned Aerial Vehicles Propulsion

PubMed Central

2014-01-01

The possibility of implementing fuel cell technology in Unmanned Aerial Vehicle (UAV) propulsion systems is considered. Potential advantages of the Proton Exchange Membrane or Polymer Electrolyte Membrane (PEMFC) and Direct Methanol Fuel Cells (DMFC), their fuels (hydrogen and methanol), and their storage systems are revised from technical and environmental standpoints. Some operating commercial applications are described. Main constraints for these kinds of fuel cells are analyzed in order to elucidate the viability of future developments. Since the low power density is the main problem of fuel cells, hybridization with electric batteries, necessary in most cases, is also explored. PMID:24600326

Fuel Cell Power Plant Initiative. Volume 2; Preliminary Design of a Fixed-Base LFP/SOFC Power System

NASA Technical Reports Server (NTRS)

Veyo, S.E.

1997-01-01

This report documents the preliminary design for a military fixed-base power system of 3 MWe nominal capacity using Westinghouse's tubular Solid Oxide Fuel Cell [SOFC] and Haldor Topsoe's logistic fuels processor [LFP]. The LFP provides to the fuel cell a methane rich sulfur free fuel stream derived from either DF-2 diesel fuel, or JP-8 turbine fuel. Fuel cells are electrochemical devices that directly convert the chemical energy contained in fuels such as hydrogen, natural gas, or coal gas into electricity at high efficiency with no intermediate heat engine or dynamo. The SOFC is distinguished from other fuel cell types by its solid state ceramic structure and its high operating temperature, nominally 1000'C. The SOFC pioneered by Westinghouse has a tubular geometry closed at one end. A power generation stack is formed by aggregating many cells in an ordered array. The Westinghouse stack design is distinguished from other fuel cell stacks by the complete absence of high integrity seals between cell elements, cells, and between stack and manifolds. Further, the reformer for natural gas [predominantly methane] and the stack are thermally and hydraulically integrated with no requirement for process water. The technical viability of combining the tubular SOFC and a logistic fuels processor was demonstrated at 27 kWe scale in a test program sponsored by the Advanced Research Projects Agency [ARPA) and carried out at the Southern California Edison's [SCE] Highgrove generating station near San Bernardino, California in 1994/95. The LFP was a breadboard design supplied by Haldor Topsoe, Inc. under subcontract to Westinghouse. The test program was completely successful. The LFP fueled the SOFC for 766 hours on JP-8 and 1555 hours of DF-2. In addition, the fuel cell operated for 3261 hours on pipeline natural gas. Over the 5582 hours of operation, the SOFC generated 118 MVVH of electricity with no perceptible degradation in performance. The LFP processed military specification JP-8 and DF-2 removing the sulfur and reforming these liquid fuels to a methane rich gaseous fuel. Results of this program are documented in a companion report titled 'Final Report-Solid Oxide Fuel Cell/ Logistic Fuels Processor 27 kWe Power System'.

Fuel cell technology for lunar surface operations

NASA Technical Reports Server (NTRS)

Deronck, Henry J.

1992-01-01

Hydrogen-oxygen fuel cells have been shown, in several NASA and contractor studies, to be an enabling technology for providing electrical power for lunar bases, outposts, and vehicles. The fuel cell, in conjunction with similar electrolysis cells, comprises a closed regenerative energy storage system, commonly referred to as a regenerative fuel cell (RFC). For stationary applications, energy densities of 1,000 watt-hours per kilograms an order of magnitude over the best rechargeable batteries, have been projected. In this RFC, the coupled fuel cell and electrolyzer act as an ultra-light battery. Electrical energy from solar arrays 'charges' the system by electrolyzing water into hydrogen and oxygen. When an electrical load is applied, the fuel cell reacts the hydrogen and oxygen to 'discharge' usable power. Several concepts for utilizing RFC's, with varying degrees of integration, have been proposed, including both primary and backup roles. For mobile power needs, such as rovers, an effective configuration may be to have only the fuel cell located on the vehicle, and to use a central electrolysis 'gas station'. Two fuel cell technologies are prime candidates for lunar power system concepts: alkaline electrolyte and proton exchange membrane. Alkaline fuel cells have been developed to a mature production power unit in NASA's Space Shuttle Orbiter. Recent advances in materials offer to significantly improve durability to the level needed for extended lunar operations. Proton exchange membrane fuel cells are receiving considerable support for hydrospace and terrestrial transportation applications. This technology promises durability, simplicity, and flexibility.

Fuel cell technology for lunar surface operations

NASA Astrophysics Data System (ADS)

Deronck, Henry J.

1992-02-01

Hydrogen-oxygen fuel cells have been shown, in several NASA and contractor studies, to be an enabling technology for providing electrical power for lunar bases, outposts, and vehicles. The fuel cell, in conjunction with similar electrolysis cells, comprises a closed regenerative energy storage system, commonly referred to as a regenerative fuel cell (RFC). For stationary applications, energy densities of 1,000 watt-hours per kilograms an order of magnitude over the best rechargeable batteries, have been projected. In this RFC, the coupled fuel cell and electrolyzer act as an ultra-light battery. Electrical energy from solar arrays 'charges' the system by electrolyzing water into hydrogen and oxygen. When an electrical load is applied, the fuel cell reacts the hydrogen and oxygen to 'discharge' usable power. Several concepts for utilizing RFC's, with varying degrees of integration, have been proposed, including both primary and backup roles. For mobile power needs, such as rovers, an effective configuration may be to have only the fuel cell located on the vehicle, and to use a central electrolysis 'gas station'. Two fuel cell technologies are prime candidates for lunar power system concepts: alkaline electrolyte and proton exchange membrane. Alkaline fuel cells have been developed to a mature production power unit in NASA's Space Shuttle Orbiter. Recent advances in materials offer to significantly improve durability to the level needed for extended lunar operations. Proton exchange membrane fuel cells are receiving considerable support for hydrospace and terrestrial transportation applications. This technology promises durability, simplicity, and flexibility.

Electrocatalytic activity of ZnS nanoparticles in direct ethanol fuel cells

NASA Astrophysics Data System (ADS)

Bredol, Michael; Kaczmarek, Michał; Wiemhöfer, Hans-Dieter

2014-06-01

Low temperature fuel cells consuming ethanol without reformation would be a major step toward the use of renewable energy sources from biomass. However, the necessary electrodes and electrocatalysts still are far from being perfect and suffer from various poisoning and deactivation processes. This work describes investigations on systems using carbon/ZnS-based electrocatalysts for ethanol oxidation in complete membrane electrode assemblies (MEAs). MEAs were built on Nafion membranes with active masses prepared from ZnS nanoparticles and Vulcan carbon support. Under operation, acetic acid and acetaldehyde were identified and quantified as soluble oxidation products, whereas the amount of CO2 generated could not be quantified directly. Overall conversion efficiencies of up to 25% were estimated from cells operated over prolonged time. From polarization curves, interrupt experiments and analysis of reaction products, mass transport problems (concentration polarization) and breakthrough losses were found to be the main deficiencies of the ethanol oxidation electrodes fabricated so far.

Non-Flow-Through Fuel Cell System Test Results and Demonstration on the SCARAB Rover

NASA Technical Reports Server (NTRS)

Scheidegger, Brianne; Burke, Kenneth; Jakupca, Ian

2012-01-01

This presentation describes the results of the demonstration of a non-flow-through PEM fuel cell as part of a power system on the SCARAB rover at the NASA Glenn Research Center. A 16-cell non-flow-through fuel cell stack from Infinity Fuel Cell and Hydrogen, Inc. was incorporated into a power system designed to act as a range extender by providing power to the SCARAB rover s hotel loads. The power system, including the non-flow-through fuel cell technology, successfully demonstrated its goal as a range extender by powering hotel loads on the SCARAB rover, making this demonstration the first to use the non-flow-through fuel cell technology on a mobile platform.

Fuel Cell Power Plants Renewable and Waste Fuels

DTIC Science & Technology

2011-01-13

of FuelCell Energy, Inc. Fuels Resources for DFC • Natural Gas and LNG • Propane • Biogas (by Anaerobicnaerobic Digestion) - Municipal Waste...FUEL RESOURCES z NATURAL GAS z PROPANE z DFC H2 (50-60%) z ETHANOL zWASTE METHANE z BIOGAS z COAL GAS Diversity of Fuels plus High Efficiency...trademarks (®) of FuelCell Energy, Inc. DFC Advantages for Biogas • More power for given amount of biogas : Higher efficiency than

Performance Analysis of Air Breathing Proton Exchange Membrane Fuel Cell Stack (PEMFCS) At Different Operating Condition

NASA Astrophysics Data System (ADS)

Sunil, V.; Venkata siva, G.; Yoganjaneyulu, G.; Ravikumar, V. V.

2017-08-01

The answer for an emission free power source in future is in the form of fuel cells which combine hydrogen and oxygen producing electricity and a harmless by product-water. A proton exchange membrane (PEM) fuel cell is ideal for automotive applications. A single cell cannot supply the essential power for any application. Hence PEM fuel cell stacks are used. The effect of different operating parameters namely: type of convection, type of draught, hydrogen flow rate, hydrogen inlet pressure, ambient temperature and humidity, hydrogen humidity, cell orientation on the performance of air breathing PEM fuel cell stack was analyzed using a computerized fuel cell test station. Then, the fuel cell stack was subjected to different load conditions. It was found that the stack performs very poorly at full capacity (runs only for 30 min. but runs for 3 hours at 50% capacity). Hence, a detailed study was undertaken to maximize the duration of the stack’s performance at peak load.

Fuel Cell Backup Power System for Grid Service and Micro-Grid in Telecommunication Applications: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Zhiwen; Eichman, Joshua D; Kurtz, Jennifer M

This paper presents the feasibility and economics of using fuel cell backup power systems in telecommunication cell towers to provide grid services (e.g., ancillary services, demand response). The fuel cells are able to provide power for the cell tower during emergency conditions. This study evaluates the strategic integration of clean, efficient, and reliable fuel cell systems with the grid for improved economic benefits. The backup systems have potential as enhanced capability through information exchanges with the power grid to add value as grid services that depend on location and time. The economic analysis has been focused on the potential revenuemore » for distributed telecommunications fuel cell backup units to provide value-added power supply. This paper shows case studies on current fuel cell backup power locations and regional grid service programs. The grid service benefits and system configurations for different operation modes provide opportunities for expanding backup fuel cell applications responsive to grid needs.« less

Electrolytes for solid oxide fuel cells

NASA Astrophysics Data System (ADS)

Fergus, Jeffrey W.

The high operating temperature of solid oxide fuel cells (SOFCs), as compared to polymer electrolyte membrane fuel cells (PEMFCs), improves tolerance to impurities in the fuel, but also creates challenges in the development of suitable materials for the various fuel cell components. In response to these challenges, intermediate temperature solid oxide fuel cells (IT-SOFCs) are being developed to reduce high-temperature material requirements, which will extend useful lifetime, improve durability and reduce cost, while maintaining good fuel flexibility. A major challenge in reducing the operating temperature of SOFCs is the development of solid electrolyte materials with sufficient conductivity to maintain acceptably low ohmic losses during operation. In this paper, solid electrolytes being developed for solid oxide fuel cells, including zirconia-, ceria- and lanthanum gallate-based materials, are reviewed and compared. The focus is on the conductivity, but other issues, such as compatibility with electrode materials, are also discussed.

Solid Polymer Electrolyte (SPE) fuel cell technology program

NASA Technical Reports Server (NTRS)

1978-01-01

Many previously demonstrated improved fuel cell features were consolidated to (1) obtain a better understanding of the observed characteristics of the operating laboratory-sized cells; (2) evaluate appropriate improved fuel cell features in 0.7 sq ft cell hardware; and (3) study the resultant fuel cell capability and determine its impact on various potential fuel cell space missions. The observed performance characteristics of the fuel cell at high temperatures and high current densities were matched with a theoretical model based on the change in Gibbs free energy voltage with respect to temperature and internal resistance change with current density. Excellent agreement between the observed and model performance was obtained. The observed performance decay with operational time on cells with very low noble metal loadings (0.05 mg/sq cm) were shown to be related to loss in surface area. Cells with the baseline amount of noble catalyst electrode loading demonstrated over 40,000 hours of stable performance.

Novel carbon-ion fuel cells. Quarterly technical report No. 9, October 1, 1995--December 31, 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cocks, F.H.

1995-12-31

This report presents research to develop an entirely new, fundamentally different class of fuel cell using a solid electrolyte that transports carbon ions. This fuel cell would use solid carbon dissolved in molten metal as a fuel reservoir and anode; expensive gaseous or liquid fuel would not be required. Thermodynamic factors favor a carbon-ion fuel cell over other fuel cell designs: a combination of enthalpy, entropy, and Gibbs free energy makes the reaction of solid carbon and oxygen very efficient, and the entropy change allows this efficiency to slightly increase at high temperatures. The high temperature exhaust of the fuelmore » cell would make it useful as a ``topping cycle``, to be followed by conventional steam turbine systems.« less

Flexible interconnects for fuel cell stacks

DOEpatents

Lenz, David J.; Chung, Brandon W.; Pham, Ai Quoc

2004-11-09

An interconnect that facilitates electrical connection and mechanical support with minimal mechanical stress for fuel cell stacks. The interconnects are flexible and provide mechanically robust fuel cell stacks with higher stack performance at lower cost. The flexible interconnects replace the prior rigid rib interconnects with flexible "fingers" or contact pads which will accommodate the imperfect flatness of the ceramic fuel cells. Also, the mechanical stress of stacked fuel cells will be smaller due to the flexibility of the fingers. The interconnects can be one-sided or double-sided.

NASA Non-Flow-Through PEM Fuel Cell System for Aerospace Applications

NASA Technical Reports Server (NTRS)

Araghi, Koorosh R.

2011-01-01

NASA is researching passive NFT Proton Exchange Membrane (PEM) fuel cell technologies for primary fuel cell power plants in air-independent applications. NFT fuel cell power systems have a higher power density than flow through systems due to both reduced parasitic loads and lower system mass and volume. Reactant storage still dominates system mass/volume considerations. NFT fuel cell stack testing has demonstrated equivalent short term performance to flow through stacks. More testing is required to evaluate long-term performance.

Marine applications for fuel cell technology: A technical memorandum

NASA Astrophysics Data System (ADS)

1986-02-01

To date, almost no attention was given to the potential marine applications for fuel cell technologies. Some of the benefits that fuel cells may offer to the utility industry may also apply to marine use. At a 1 day workshop the Office of Technology Assessment found fuel cells to offer advantages in applications requiring quiet operations, applications where throttle settings are constantly changed, and for small submarines. Fuel cells are not expected to penetrate marine markets until they become firmly established in the commercial utility section.

Method for in situ carbon deposition measurement for solid oxide fuel cells

NASA Astrophysics Data System (ADS)

Kuhn, J.; Kesler, O.

2014-01-01

Previous methods to measure carbon deposition in solid oxide fuel cell (SOFC) anodes do not permit simultaneous electrochemical measurements. Electrochemical measurements supplemented with carbon deposition quantities create the opportunity to further understand how carbon affects SOFC performance and electrochemical impedance spectra (EIS). In this work, a method for measuring carbon in situ, named here as the quantification of gasified carbon (QGC), was developed. TGA experiments showed that carbon with a 100 h residence time in the SOFC was >99.8% gasified. Comparison of carbon mass measurements between the TGA and QGC show good agreement. In situ measurements of carbon deposition in SOFCs at varying molar steam/carbon ratios were performed to further validate the QGC method, and suppression of carbon deposition with increasing steam concentration was observed, in agreement with previous studies. The technique can be used to investigate in situ carbon deposition and gasification behavior simultaneously with electrochemical measurements for a variety of fuels and operating conditions, such as determining conditions under which incipient carbon deposition is reversible.

Preparation and evaluation of advanced catalysts for phosphoric acid fuel cells

NASA Technical Reports Server (NTRS)

Stonehart, P.; Baris, J.; Hockmuth, J.; Pagliaro, P.

1984-01-01

The platinum electrocatalysts were characterized for their crystallite sizes and the degree of dispersion on the carbon supports. One application of these electrocatalysts was for anodic oxidation of hydrogen in hot phosphoric acid fuel cells, coupled with the influence of low concentrations of carbon monoxide in the fuel gas stream. In a similar way, these platinum on carbon electrocatalysts were evaluated for oxygen reduction in hot phosphoric acid. Binary noble metal alloys were prepared for anodic oxidation of hydrogen and noble metal-refractory metal mixtures were prepared for oxygen reduction. An exemplar alloy of platinum and palladium (50/50 atom %) was discovered for anodic oxidation of hydrogen in the presence of carbon monoxide, and patent disclosures were submitted. For the cathode, platinum-vanadium alloys were prepared showing improved performance over pure platinum. Preliminary experiments on electrocatalyst utilization in electrode structures showed low utilization of the noble metal when the electrocatalyst loading exceeded one weight percent on the carbon.

Purge gas protected transportable pressurized fuel cell modules and their operation in a power plant

DOEpatents

Zafred, Paolo R.; Dederer, Jeffrey T.; Gillett, James E.; Basel, Richard A.; Antenucci, Annette B.

1996-01-01

A fuel cell generator apparatus and method of its operation involves: passing pressurized oxidant gas, (O) and pressurized fuel gas, (F), into fuel cell modules, (10 and 12), containing fuel cells, where the modules are each enclosed by a module housing (18), surrounded by an axially elongated pressure vessel (64), where there is a purge gas volume, (62), between the module housing and pressure vessel; passing pressurized purge gas, (P), through the purge gas volume, (62), to dilute any unreacted fuel gas from the modules; and passing exhaust gas, (82), and circulated purge gas and any unreacted fuel gas out of the pressure vessel; where the fuel cell generator apparatus is transpatable when the pressure vessel (64) is horizontally disposed, providing a low center of gravity.

Scientific Aspects of Polymer Electrolyte Fuel Cell Durability and Degradation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borup, Rodney; Meyers, Jeremy; Pivovar, Bryan

Rod Borup is a Team Leader in the fuel cell program at Los Alamos National Lab in Los Alamos, New Mexico. He received his B.S.E. in Chemical Engineering from the University of Iowa in 1988 and his Ph.D. from the University of Washington in 1993. He has worked on fuel cell technology since 1994, working in the areas of hydrogen production and PEM fuel cell stack components. He has been awarded 12 U.S. patents, authored over 40 papers related to fuel cell technology, and presented over 50 oral papers at national meetings. His current main research area is related tomore » water transport in PEM fuel cells and PEM fuel cell durability. Recently, he was awarded the 2005 DOE Hydrogen Program R&D Award for the most significant R&D contribution of the year for his team's work in fuel cell durability and was the Principal Investigator for the 2004 Fuel Cell Seminar (San Antonio, TX, USA) Best Poster Award. Jeremy Meyers is an Assistant Professor of materials science and engineering and mechanical engineering at the University of Texas at Austin, where his research focuses on the development of electrochemical energy systems and materials. Prior to joining the faculty at Texas, Jeremy worked as manager of the advanced transportation technology group at UTC Power, where he was responsible for developing new system designs and components for automotive PEM fuel cell power plants. While at UTC Power, Jeremy led several customer development projects and a DOE-sponsored investigation into novel catalysts and membranes for PEM fuel cells. Jeremy has coauthored several papers on key mechanisms of fuel cell degradation and is a co-inventor of several patents. In 2006, Jeremy and several colleagues received the George Mead Medal, UTC's highest award for engineering achievement, and he served as the co-chair of the Gordon Research Conference on fuel cells. Jeremy received his Ph.D. in Chemical Engineering from the University of California at Berkeley and holds a Bachelor's Degree in Chemical Engineering from Stanford University. Bryan Pivovar received his B.S. in Chemical Engineering from the University of Wisconsin in 1994. He completed his Ph.D. in Chemical Engineering at the University of Minnesota in 2000 under the direction of Profs. Ed Cussler and Bill Smyrl, studying transport properties in fuel cell electrolytes. He continued working in the area of polymer electrolyte fuel cells at Los Alamos National Laboratory as a post-doc (2000-2001), as a technical staff member (2001-2005), and in his current position as a team leader (2005-present). In this time, Bryan's research has expanded to include further aspects of fuel cell operation, including electrodes, subfreezing effects, alternative polymers, hydroxide conductors, fuel cell interfaces, impurities, water transport, and high-temperature membranes. Bryan has served at various levels in national and international conferences and workshops, including organizing a DOE sponsored workshop on freezing effects in fuel cells and an ARO sponsored workshop on alkaline membrane fuel cells, and he was co-chair of the 2007 Gordon Research Conference on Fuel Cells. Minoru Inaba is a Professor at the Department of Molecular Science and Technology, Faculty of Engineering, Doshisha University, Japan. He received his B.Sc. from the Faculty of Engineering, Kyoto University, in 1984 and his M.Sc. in 1986 and his Dr. Eng. in 1995 from the Graduate School of Engineering, Kyoto University. He has worked on electrochemical energy conversion systems including fuel cells and lithium-ion batteries at Kyoto University (1992-2002) and at Doshisha University (2002-present). His primary research interest is the durability of polymer electrolyte fuel cells (PEFCs), in particular, membrane degradation, and he has been involved in NEDO R&D research projects on PEFC durability since 2001. He has authored over 140 technical papers and 30 review articles. Kenichiro Ota is a Professor of the Chemical Energy Laboratory at the Graduate School of Engineering, Yokohama National University, Japan. He received his B.S.E. in Applied Chemistry from the University of Tokyo in 1968 and his Ph.D. from the University of Tokyo in 1973. He has worked on hydrogen energy and fuel cells since 1974, working on materials science for fuel cells and water electrolysis. He has published more than 150 original papers, 70 review papers, and 50 scientific books. He is now the president of the Hydrogen Energy Systems Society of Japan, the chairman of the Fuel Cell Research Group of the Electrochemical Society of Japan, and the chairman of the National Committee for the Standardization of the Stationary Fuel Cells. ABSTRACT TRUNCATED« less

Generator module architecture for a large solid oxide fuel cell power plant

DOEpatents

Gillett, James E.; Zafred, Paolo R.; Riggle, Matthew W.; Litzinger, Kevin P.

2013-06-11

A solid oxide fuel cell module contains a plurality of integral bundle assemblies, the module containing a top portion with an inlet fuel plenum and a bottom portion receiving air inlet feed and containing a base support, the base supports dense, ceramic exhaust manifolds which are below and connect to air feed tubes located in a recuperator zone, the air feed tubes passing into the center of inverted, tubular, elongated, hollow electrically connected solid oxide fuel cells having an open end above a combustion zone into which the air feed tubes pass and a closed end near the inlet fuel plenum, where the fuel cells comprise a fuel cell stack bundle all surrounded within an outer module enclosure having top power leads to provide electrical output from the stack bundle, where the fuel cells operate in the fuel cell mode and where the base support and bottom ceramic air exhaust manifolds carry from 85% to all 100% of the weight of the stack, and each bundle assembly has its own control for vertical and horizontal thermal expansion control.

Pt/Pd electrocatalyst electrons for fuel cells

DOEpatents

Stonehart, P.

1981-11-03

This invention relates to improved electrochemical cells and to novel electrodes for use therein. In particular, the present invention comprises a fuel cell used primarily for the consumption of impure hydrogen fuels containing carbon monoxide or carbonaceous fuels where the electrode in contact with the fuel is not substantially poisoned by carbon monoxide. The anode of the fuel cell comprises a Pd/Pt alloy supported on a graphitized or partially graphitized carbon material. Fuel cells which comprise as essential elements a fuel electrode, an oxidizing electrode, and an electrolyte between said electrodes are devices for the direct production of electricity through the electrochemical combustion of a fuel and oxidant. These devices are recognized for their high efficiency as energy conversion units, since unlike conventional combustion engines, they are not subject to the limitations of the Carnot heat cycle. It is the primary object of the present invention to provide an electrode having high electrochemical activity for an electrochemical cell. It is another object of the present invention to provide an electrode having an electro-catalyst which is highly resistant to the corrosive environment of an electrochemical cell.

Transient deformational properties of high temperature alloys used in solid oxide fuel cell stacks

NASA Astrophysics Data System (ADS)

Molla, Tesfaye Tadesse; Kwok, Kawai; Frandsen, Henrik Lund

2017-05-01

Stresses and probability of failure during operation of solid oxide fuel cells (SOFCs) is affected by the deformational properties of the different components of the SOFC stack. Though the overall stress relaxes with time during steady state operation, large stresses would normally appear through transients in operation including temporary shut downs. These stresses are highly affected by the transient creep behavior of metallic components in the SOFC stack. This study investigates whether a variation of the so-called Chaboche's unified power law together with isotropic hardening can represent the transient behavior of Crofer 22 APU, a typical iron-chromium alloy used in SOFC stacks. The material parameters for the model are determined by measurements involving relaxation and constant strain rate experiments. The constitutive law is implemented into commercial finite element software using a user-defined material model. This is used to validate the developed constitutive law to experiments with constant strain rate, cyclic and creep experiments. The predictions from the developed model are found to agree well with experimental data. It is therefore concluded that Chaboche's unified power law can be applied to describe the high temperature inelastic deformational behaviors of Crofer 22 APU used for metallic interconnects in SOFC stacks.

Cover and startup gas supply system for solid oxide fuel cell generator

DOEpatents

Singh, P.; George, R.A.

1999-07-27

A cover and startup gas supply system for a solid oxide fuel cell power generator is disclosed. Hydrocarbon fuel, such as natural gas or diesel fuel, and oxygen-containing gas are supplied to a burner. Combustion gas exiting the burner is cooled prior to delivery to the solid oxide fuel cell. The system mixes the combusted hydrocarbon fuel constituents with hydrogen which is preferably stored in solid form to obtain a non-explosive gas mixture. The system may be used to provide both non-explosive cover gas and hydrogen-rich startup gas to the fuel cell. 4 figs.

Cover and startup gas supply system for solid oxide fuel cell generator

DOEpatents

Singh, Prabhakar; George, Raymond A.

1999-01-01

A cover and startup gas supply system for a solid oxide fuel cell power generator is disclosed. Hydrocarbon fuel, such as natural gas or diesel fuel, and oxygen-containing gas are supplied to a burner. Combustion gas exiting the burner is cooled prior to delivery to the solid oxide fuel cell. The system mixes the combusted hydrocarbon fuel constituents with hydrogen which is preferably stored in solid form to obtain a non-explosive gas mixture. The system may be used to provide both non-explosive cover gas and hydrogen-rich startup gas to the fuel cell.

Preventing CO poisoning in fuel cells

DOEpatents

Gottesfeld, Shimshon

1990-01-01

Proton exchange membrane (PEM) fuel cell performance with CO contamination of the H.sub.2 fuel stream is substantially improved by injecting O.sub.2 into the fuel stream ahead of the fuel cell. It is found that a surface reaction occurs even at PEM operating temperatures below about 100.degree. C. to oxidatively remove the CO and restore electrode surface area for the H.sub.2 reaction to generate current. Using an O.sub.2 injection, a suitable fuel stream for a PEM fuel cell can be formed from a methanol source using conventional reforming processes for producing H.sub.2.

Equation of state, initiation, and detonation of pure ammonium nitrate

NASA Astrophysics Data System (ADS)

Robbins, D. L.; Sheffield, S. A.; Dattelbaum, D. M.; Velisavljevic, N.; Stahl, D. B.

2009-06-01

Ammonium nitrate (AN) is a widely used fertilizer and mining explosive throughout the world. One of the more common explosives using AN is called ANFO, a mixture of AN prills and fuel oil in a 94:6 ratio by weight. The AN prills are specially made to absorb the fuel oil, forming a mixture that reacts under shock loading through a diffusion-controlled process, resulting in a non-ideal explosive with detonation velocities around 4 km/s. While there are a number of studies on ANFO, there are only a few studies relating to the equation of state (EOS) and detonation properties of pure AN - resulting mainly from studies of accidents that have occurred during transportation of large quantities of AN. We present the results of a series of gas gun-driven plate impact experiments on pressed AN ranging in density from 1.72 to 0.9 g/cm^3. Several of the high density experiments were performed in front surface impact geometry, in which pressed AN disks were built into the projectile front and impacted onto LiF windows. Additional experiments at low density have been done in ``half cell'' multiple magnetic gauge gun experiments. From this work a complete unreacted EOS has been developed, as well as some initiation and detonation information. Additional high pressure x-ray diffraction experiments in diamond anvil cells have provided a static isotherm for AN.

Fuel cells for low power applications

NASA Astrophysics Data System (ADS)

Heinzel, A.; Hebling, C.; Müller, M.; Zedda, M.; Müller, C.

Electronic devices show an ever-increasing power demand and thus, require innovative concepts for power supply. For a wide range of power and energy capacity, membrane fuel cells are an attractive alternative to conventional batteries. The main advantages are the flexibility with respect to power and capacity achievable with different devices for energy conversion and energy storage, the long lifetime and long service life, the good ecological balance, very low self-discharge. Therefore, the development of fuel cell systems for portable electronic devices is an attractive, although also a challenging, goal. The fuel for a membrane fuel cell might be hydrogen from a hydride storage system or methanol/water as a liquid alternative. The main differences between the two systems are the much higher power density for hydrogen fuel cells, the higher energy density per weight for the liquid fuel, safety aspects and infrastructure for fuel supply for hydride materials. For different applications, different system designs are required. High power cells are required for portable computers, low power methanol fuel cells required for mobile phones in hybrid systems with batteries and micro-fuel cells are required, e.g. for hand held PCs in the sub-Watt range. All these technologies are currently under development. Performance data and results of simulations and experimental investigations will be presented.

An Overview of Stationary Fuel Cell Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

DR Brown; R Jones

1999-03-23

Technology developments occurring in the past few years have resulted in the initial commercialization of phosphoric acid (PA) fuel cells. Ongoing research and development (R and D) promises further improvement in PA fuel cell technology, as well as the development of proton exchange membrane (PEM), molten carbonate (MC), and solid oxide (SO) fuel cell technologies. In the long run, this collection of fuel cell options will be able to serve a wide range of electric power and cogeneration applications. A fuel cell converts the chemical energy of a fuel into electrical energy without the use of a thermal cycle ormore » rotating equipment. In contrast, most electrical generating devices (e.g., steam and gas turbine cycles, reciprocating engines) first convert chemical energy into thermal energy and then mechanical energy before finally generating electricity. Like a battery, a fuel cell is an electrochemical device, but there are important differences. Batteries store chemical energy and convert it into electrical energy on demand, until the chemical energy has been depleted. Depleted secondary batteries may be recharged by applying an external power source, while depleted primary batteries must be replaced. Fuel cells, on the other hand, will operate continuously, as long as they are externally supplied with a fuel and an oxidant.« less

The Business Case for Fuel Cells: Delivering Sustainable Value

DOE Office of Scientific and Technical Information (OSTI.GOV)

Curtin, Sandra; Gangi, Jennifer

This report, written and compiled by Argonne National Laboratory and the Fuel Cell and Hydrogen Energy Association with support from the Fuel Cell Technologies Office, provides an overview of private sector fuel cell installations at U.S. businesses as of December 31, 2016. Over the past few decades, hundreds of thousands of fuel cells have been installed around the world, for primary or backup power, as well as in various other applications including portable and emergency backup power. Fuel cells have also been deployed in other applications such as heat and electricity for homes and apartments, material handling, passenger vehicles, buses,more » and remote, off-grid sites.« less

The US Army Foreign Comparative Test fuel cell program

NASA Astrophysics Data System (ADS)

Bostic, Elizabeth; Sifer, Nicholas; Bolton, Christopher; Ritter, Uli; Dubois, Terry

The US Army RDECOM initiated a Foreign Comparative Test (FCT) Program to acquire lightweight, high-energy dense fuel cell systems from across the globe for evaluation as portable power sources in military applications. Five foreign companies, including NovArs, Smart Fuel Cell, Intelligent Energy, Ballard Power Systems, and Hydrogenics, Inc., were awarded competitive contracts under the RDECOM effort. This paper will report on the status of the program as well as the experimental results obtained from one of the units. The US Army has interests in evaluating and deploying a variety of fuel cell systems, where these systems show added value when compared to current power sources in use. For low-power applications, fuel cells utilizing high-energy dense fuels offer significant weight savings over current battery technologies. This helps reduce the load a solider must carry for longer missions. For high-power applications, the low operating signatures (acoustic and thermal) of fuel cell systems make them ideal power generators in stealth operations. Recent testing has been completed on the Smart Fuel Cell A25 system that was procured through the FCT program. The "A-25" is a direct methanol fuel cell hybrid and was evaluated as a potential candidate for soldier and sensor power applications.

A comparison of hydrogen, methanol and gasoline as fuels for fuel cell vehicles: implications for vehicle design and infrastructure development

NASA Astrophysics Data System (ADS)

Ogden, Joan M.; Steinbugler, Margaret M.; Kreutz, Thomas G.

All fuel cells currently being developed for near term use in electric vehicles require hydrogen as a fuel. Hydrogen can be stored directly or produced onboard the vehicle by reforming methanol, or hydrocarbon fuels derived from crude oil (e.g., gasoline, diesel, or middle distillates). The vehicle design is simpler with direct hydrogen storage, but requires developing a more complex refueling infrastructure. In this paper, we present modeling results comparing three leading options for fuel storage onboard fuel cell vehicles: (a) compressed gas hydrogen storage, (b) onboard steam reforming of methanol, (c) onboard partial oxidation (POX) of hydrocarbon fuels derived from crude oil. We have developed a fuel cell vehicle model, including detailed models of onboard fuel processors. This allows us to compare the vehicle performance, fuel economy, weight, and cost for various vehicle parameters, fuel storage choices and driving cycles. The infrastructure requirements are also compared for gaseous hydrogen, methanol and gasoline, including the added costs of fuel production, storage, distribution and refueling stations. The delivered fuel cost, total lifecycle cost of transportation, and capital cost of infrastructure development are estimated for each alternative. Considering both vehicle and infrastructure issues, possible fuel strategies leading to the commercialization of fuel cell vehicles are discussed.

Development of a 5 kW Prototype Coal-Based Fuel Cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chuang, Steven S.C.; Mirzababaei, Jelvehnaz; Rismanchian, Azadeh

2014-01-20

The University of Akron Fuel Cell Laboratory pioneered the development of a laboratory scale coal-based fuel cell, which allows the direct use of high sulfur content coal as fuel. The initial research and coal fuel cell technology development (“Coal-based Fuel Cell,” S. S. C. Chuang, PCT Int. Appl. 2006, i.e., European Patent Application, 35 pp. CODEN: PIXXD2 WO 2006028502 A2 20060316) have demonstrated that it is feasible to electrochemically oxidize carbon to CO2, producing electricity. The key innovative concept of this coal-based fuel cell technology is that carbon in coal can be converted through an electrochemical oxidation reaction into manageablemore » carbon dioxide, efficiently generating electricity without involving coal gasification, reforming, and water-gas shift reaction. This study has demonstrated that electrochemical oxidation of carbon can take place on the Ni anode surface and the CO and CO 2 product produced can further react with carbon to initiate the secondary reaction. A carbon injection system was developed to inject the solid fuel without bringing air into the anode chamber; a fuel cell stack was developed and tested to demonstrate the feasibility of the fuel cell stack. Further improvement of anode catalyst activity and durability is needed to bring this novel coal fuel cell to a highly efficient, super clean, multi-use electric generation technology, which promises to provide low cost electricity by expanding the utilization of U.S. coal supplies and relieving our dependence on foreign oil.« less

40 CFR 600.311-12 - Determination of values for fuel economy labels.

Code of Federal Regulations, 2014 CFR

2014-07-01

... value from paragraph (a) of this section, in miles per kW-hour. (4) For hydrogen fuel cell vehicles... for hydrogen fuel cell vehicles. MPG = The combined fuel economy value from paragraph (a) of this... hydrogen fuel cell vehicles. Average Annual Miles = The estimated annual mileage figure provided by EPA, in...

40 CFR 600.311-12 - Determination of values for fuel economy labels.

Code of Federal Regulations, 2013 CFR

2013-07-01

... value from paragraph (a) of this section, in miles per kW-hour. (4) For hydrogen fuel cell vehicles... for hydrogen fuel cell vehicles. MPG = The combined fuel economy value from paragraph (a) of this... hydrogen fuel cell vehicles. Average Annual Miles = The estimated annual mileage figure provided by EPA, in...

Unitized regenerative fuel cell system

NASA Technical Reports Server (NTRS)

Burke, Kenneth A. (Inventor)

2008-01-01

A Unitized Regenerative Fuel Cell system uses heat pipes to convey waste heat from the fuel cell stack to the reactant storage tanks. The storage tanks act as heat sinks/sources and as passive radiators of the waste heat from the fuel cell stack. During charge up, i.e., the electrolytic process, gases are conveyed to the reactant storage tanks by way of tubes that include dryers. Reactant gases moving through the dryers give up energy to the cold tanks, causing water vapor in with the gases to condense and freeze on the internal surfaces of the dryer. During operation in its fuel cell mode, the heat pipes convey waste heat from the fuel cell stack to the respective reactant storage tanks, thereby heating them such that the reactant gases, as they pass though the respective dryers on their way to the fuel cell stacks retrieve the water previously removed.

Advanced fuel cell concepts for future NASA missions

NASA Technical Reports Server (NTRS)

Stedman, J. K.

1987-01-01

Studies of primary fuel cells for advanced all electric shuttle type vehicles show an all fuel cell power system with peak power capability of 100's of kW to be potentially lighter and have lower life cycle costs than a hybrid system using advanced H2O2 APU's for peak power and fuel cells for low power on orbit. Fuel cell specific weights of 1 to 3 lb/kW, a factor of 10 improvement over the orbiter power plant, are projected for the early 1990's. For satellite applications, a study to identify high performance regenerative hydrogen oxygen fuel cell concepts for geosynchronous orbit was completed. Emphasis was placed on concepts with the potential for high energy density (Wh/lb) and passive means for water and heat management to maximize system reliability. Both alkaline electrolyte and polymer membrane fuel cells were considered.

Optimisation of air cooled, open-cathode fuel cells: Current of lowest resistance and electro-thermal performance mapping

NASA Astrophysics Data System (ADS)

Meyer, Quentin; Ronaszegi, Krisztian; Pei-June, Gan; Curnick, Oliver; Ashton, Sean; Reisch, Tobias; Adcock, Paul; Shearing, Paul R.; Brett, Daniel J. L.

2015-09-01

Selecting the ideal operating point for a fuel cell depends on the application and consequent trade-off between efficiency, power density and various operating considerations. A systematic methodology for determining the optimal operating point for fuel cells is lacking; there is also the need for a single-value metric to describe and compare fuel cell performance. This work shows how the 'current of lowest resistance' can be accurately measured using electrochemical impedance spectroscopy and used as a useful metric of fuel cell performance. This, along with other measures, is then used to generate an 'electro-thermal performance map' of fuel cell operation. A commercial air-cooled open-cathode fuel cell is used to demonstrate how the approach can be used; in this case leading to the identification of the optimum operating temperature of ∼45 °C.

Selection of optimal sensors for predicting performance of polymer electrolyte membrane fuel cell

NASA Astrophysics Data System (ADS)

Mao, Lei; Jackson, Lisa

2016-10-01

In this paper, sensor selection algorithms are investigated based on a sensitivity analysis, and the capability of optimal sensors in predicting PEM fuel cell performance is also studied using test data. The fuel cell model is developed for generating the sensitivity matrix relating sensor measurements and fuel cell health parameters. From the sensitivity matrix, two sensor selection approaches, including the largest gap method, and exhaustive brute force searching technique, are applied to find the optimal sensors providing reliable predictions. Based on the results, a sensor selection approach considering both sensor sensitivity and noise resistance is proposed to find the optimal sensor set with minimum size. Furthermore, the performance of the optimal sensor set is studied to predict fuel cell performance using test data from a PEM fuel cell system. Results demonstrate that with optimal sensors, the performance of PEM fuel cell can be predicted with good quality.

Synthesis, characterization and optimization of platinum-alloy nanoparticle catalysts in proton exchange membrane fuel cells

NASA Astrophysics Data System (ADS)

Srivastava, Ratndeep

Renewable hydrogen-fuelled proton exchange membrane (PEMFC) fuel cells have consistently demonstrated great promise as a future source of energy due to their high conversion efficiency, lower temperature of operation and lack of greenhouse emissions. One of the major impediments in the commercialization of polymer electrolyte membrane fuel cells is the insufficient catalytic reactivity and higher cost of Pt electrocatalysts which are utilized for the electroreduction of oxygen from air. This dissertation focuses primarily on a family of Pt alloy fuel cell electrocatalysts referred to as de-alloyed core-shell electrocatalysts. These materials are bimetallic or multimetallic nanoparticles, mostly supported on conductive supports which were first described in a dissertation by Dr. S. Koh earlier in 2009.1 De-alloyed Pt nanoparticle electrocatalysts are formed from base metal rich binary Pt-M and ternary Pt-M1-M 2 (M, M1, M2 = Cu, Co, Ni, Fe and Cr) alloy nanoparticle precursors. The precursors are transformed and activated by electrochemical selective dissolution of the less noble metal component of the precursors (de-alloying). They have shown exceptional activity for oxygen reduction reaction (ORR) in idealized electrochemical half cell measurements, in particular rotating disk electrode experiments. However, these materials were never tested or implemented in realistic Membrane Electrode Assemblies (MEA) and single PEM fuel cells. The objective of this work was to implement de-alloyed Pt particle catalysts in realistic fuel cell electrode layers as well as a detailed characterization of their behavior and stability. The major challenges of MEA implementation consists of the behavior of the new nanostructured electrocatalysts inside the complex three-phase interface of polymer membrane ionomer, liquid water, metal catalyst, support, and reactant gas. Activity measurements were followed by medium and long-term durability analysis by potential cycling of the membrane electrode assemblies to high potentials. These de-alloyed catalysts show improved resistance to electro-chemical surface area degradation as compared to state of the art available commercial Pt/C catalysts. TEM imaging with combination of electrochemical characterization helps in determining the mechanisms for particle growth and failures. Anomalous small angle x-ray scattering (ASAXS) and x-ray diffraction (XRD) techniques were also used in the characterization of these materials.

Grove Medal Address - investing in the fuel cell business

NASA Astrophysics Data System (ADS)

Rasul, Firoz

Successful commercialization of fuel cells will require significant investment. To attract this funding, the objective must be commercially driven and the financing will have to be viewed as an investment in the business of fuel cells rather than just the funding of technology development. With the recent advancements in fuel cells and demonstrations of fuel cell power systems in stationary and transport applications, an industry has begun to emerge and it is attracting the attention of institutional and corporate investors, in addition to the traditional government funding. Although, the strategic importance of fuel cells as a versatile, efficient and cleaner power source of the future as well as an `engine' for economic growth and job creation has now been understood by several governments, major corporations have just begun to recognize the enormous potential of the fuel cell for it to become as ubiquitous for electrical power as the microprocessor has become for computing power. Viewed as a business, fuel cells must meet the commercial requirements of price competitiveness, productivity enhancement, performance and reliability, in addition to environmental friendliness. As fuel cell-based products exhibit commercial advantages over conventional power sources, the potential for higher profits and superior returns will attract the magnitude of investment needed to finance the development of products for the varied applications, the establishment of high volume manufacturing capabilities, and the creation of appropriate fuel and service infrastructures for these new products based on a revolutionary technology. Today, the fuel cell industry is well-positioned to offer the investing public opportunities to reap substantial returns through their participation at this early stage of growth of the industry.

Soy Biodiesel and Petrodiesel Emissions Differ in Size, Chemical Composition and Stimulation of Inflammatory Responses in Cells and Animals

PubMed Central

Fukagawa, Naomi K.; Li, Muyao; Poynter, Matthew E.; Palmer, Brian C.; Parker, Erin; Kasumba, John; Holmén, Britt A.

2013-01-01

Debate about the biological effects of biodiesel exhaust emissions exists due to variation in methods of exhaust generation and biological models used to assess responses. Because studies in cells do not necessarily reflect the integrated response of a whole animal, experiments were conducted in two human cell lines representing bronchial epithelial cells and macrophages and female mice using identical particle suspensions of raw exhaust generated by a Volkswagen light-duty diesel engine using petrodiesel (B0) and a biodiesel blend (B20: 20% soy biodiesel/80% B0 by volume). Tailpipe particle emissions measurement showed B0 generated two times more particle mass, larger ultrafine particle number distribution modes, and particles of more nonpolar organic composition than the B20 fuel. Biological assays (inflammatory mediators, oxidative stress biomarkers) demonstrated that particulate matter (PM) generated by combustion of the two fuels induced different responses in in vitro and in vivo models. Concentrations of inflammatory mediators (Interleukin-6, IL-6; Interferon-gamma-induced Protein 10, IP-10; Granulocyte-stimulating factor, G-CSF) in the medium of B20-treated cells and in bronchoalveolar lavage fluid of mice exposed to B20 were ~20–30% higher than control or B0 PM, suggesting that addition of biodiesel to diesel fuels will reduce PM emissions but not necessarily adverse health outcomes. PMID:24053625