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Fuel cell system models are key tools for automotive fuel cell system engineers to properly size components to meet design parameters without compromising efficiency by over-sizing parasitic components. A transient fuel cell system-level model is being developed that includes a simplified transient thermal and parasitics model. Model validation is achieved using a small 1.2 kW fuel cell system due to its availability. While this is a relatively small stack compared to a full size automotive stack, the power, general thermal behavior, and compressor parasitics portions of the model can be scaled to any number of cells with any size membrane area. With flexibility in membrane size and cell numbers, this model can be easily scaled to match full automotive stacks of any size. The electrochemical model employs a generalized polarization curve to approximate system performance and efficiency parameters needed for the other components of the model.

A discussion of the need for and the advantages of fuel cell systems and technologies is presented as is a description of the multi– / inter–disciplinary efforts currently underway at Virginia Polytechnic Institute and State University (Virginia Tech) for fuel cell system development. As part of these efforts, the Virginia Tech GATE (Graduate Automotive Technology Education) Center for Automotive Fuel Cell Systems is collaborating in research and education with both government and industry. The current focus of the center is the development of research, laboratory and educational programs in support of the design and implementation of fuel cell systems technology in advanced vehicles. Five GATE Fellowships are being funded by the DoE at the center starting Fall of 1999.

Energy Partners developed, designed, built, and tested a 20 kWe automotive fuel cell stack, which was then used in Virginia Tech's 1999 Future Car Challenge hybrid electric vehicle. Performance of the stack on a “state-of-the-art” test stand at Energy Partners is compared to data taken while the stack was in operation in the vehicle. Overall, the stack in the vehicle performed as expected. The difference in performance may be explained by different operating conditions. System considerations, such as temperature, humidification, reactant stoichiometry, monitor and control software necessary for proper fuel cell operation, are presented and reviewed.