The Effect of Thickness on the Performance of Molten Carbonate Fuel Cell Cathodes

Abstract
Polarization data were obtained for the reduction of oxygen on porous lithiated nickel oxide fuel cell cathodes in lithium‐potassium carbonate electrolyte at 650°C. Cathode thickness was varied from 0.013 to 0.112 cm with the maximum performance occurring for cathodes of approximately 0.08 cm thickness. The polarization data were optimized for each electrode by varying the electrode electrolyte content in a half‐cell apparatus. The optimum content occurred when the combination of internal ionic resistive, diffusional, and activation losses resulted in minimum overvoltage.