Analytical fuel cell modeling

It will be shown that some important characteristics of stationary operating fuel cells can be understood by analyzing a simple basic isothermal 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 compared with published data of a bench-scale molten carbonate fuel cell (MCFC). Simple expressions relating the cell voltage, cell current and 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 shown that a non-homogeneous current distribution yields an extra overpotential in the order of 10 mV for an MCFC.