Simulation of influences of layer thicknesses in an alkaline fuel cell

A computational simulation was conducted by using a one-dimensional isother mal model for an alkaline fuel cell (AFC) single cell to investigate influe nces of the thicknesses of the separator, catalyst layer, and gas-diffusion layer in an AFC. The cell polarizations were predicted at various thicknes ses and their influences were also analysed. Thickening the separator layer decreased the limiting current density and increased the slope of the ohmi c polarization region. Investigation on the thickness of the anode catalyst layer showed that the optimum thickness varied between 0.04-0.15 mm accord ing to the cell voltage. The thickness of the cathode catalyst layer signif icantly influenced the cell performance. Also, a limitation of thickness ef fect in the cathode catalyst layer was observed. This limitation was consid ered to be caused by the mass transfer resistance of the electrolyte.