ANALYTICAL FUEL-CELL MODELING

It will be shown that some important characteristics of stationary ope rating fuel cells can be understood by analyzing a simple basic isothe rmal cell model. The model is independent of the type of fuel cell and will be used for a general description of cells supplied with gaseous fuel and oxidant. An example is also given in which the results are c ompared with published data of a bench-scale molten carbonate fuel cel l (MCFC). Simple expressions relating the cell voltage, cell current a nd fuel utilization are derived and found to be accurate despite their simplicity. Deviations in analytically calculated cell voltages from numerical computations are in the order of mV. Moreover, it will be sh own that a non-homogeneous current distribution yields an extra overpo tential in the order of 10 mV for an MCFC.