Heat and mass transfer design issues in PEM fuel cell hardware

Dynamic moisture transport within polymeric electrolytes influences PEM fuel cell performance. Lowering electrolyte moisture content leads to decreased ionic transport rates, and other long term effects including polymer degradation. Results illustrate anode dehydration, the effect of water transport concurrent with the proton flux, is significant in single cells at current densities exceeding 500 ma/cm{sup 2}, and at higher temperatures. Evaporation and condensation to and from the gas phase contribute significantly to the cell thermal flows. Several strategies for successful high current density operation of these devices are presented. 9 refs., 7 figs.