Non-isothermal Modeling of Polymer Electrolyte Membrane Fuel Cell Stacks

A mathematical model has been developed to analyze the heat transfer and its effect on the performance of a polymer electrolyte membrane (PEM) fuel cell stack. It was found that the individual cell voltage is mainly affected by the temperature when the effects of concentration variances are minimized by ensuring sufficient reacting flow uniformity for the cells in the stack. The coolant flow rate should be properly controlled according to the amount of heat generation to reduce the cell-to-cell voltage variance and to save the pumping power as well. The stack performance can be improved by optimizing stack geometrical parameters and operating conditions.