Temperature Profiles of an Air-Cooled Pem Fuel Cell Stack Under Active and Passive Cooling Operation

AbstractThermal engineering of Polymer Electrolyte Membrane (PEM) fuel cells is an operational requirement for optimum power generation. The first order analysis involves the monitoring of stack temperatures and acts as an input for process control. Excessive temperatures dehydrate the membrane and increase the internal losses of the system. A 3-cell air-cooled PEM fuel cell with an active area of 240 cm2 per cell was developed to analyze the thermal behavior of fuel cells under operation to the second order of heat transfer analysis. Here, direct analysis on the physical manifestations of stack temperatures is presented. The tests were conducted at dry reactant conditions and subjected to active (positive pressure) and passive cooling modes. Zonal cell temperatures were obtained that is capable of identifying active sites within the cells. Averaged stack temperatures were then formulated from the zonal temperatures that represent the required input for process control