ANALYSIS OF PERFORMANCE OF MOLTEN-CARBONA TE FUEL-CELL .4. PERFORMANCE FORMULATION BASED ON CATHODE REACTION-MECHANISMS

The formulation for the performance of Molten Carbonate Fuel Cell (MCF C) is required tp estimate the efficiency of a MCFC plant or to simula te the inner state of a MCFC stack. The formulation should have good a ccuracy under various operating conditions. However, the performances estimated by earlier formulations have been found to deviate from thos e measured under low O-2 and CO2 cathode partial pressures. To solve t his problem, data were collected with many single cells operated under systematic cathode gas conditions. The cathode overpotential formulat ion was improved based on the consideration of cathode reaction mechan isms. As a result, it is shown that the behavior of cathode overpotent ial is well estimated from the assumed partial pressure dependence of mixed diffusion of superoxide ion O-2(-) and CO2 in (Li+K)/CO3 molten carbonate.