Polarization model for molten carbonate fuel cell cathodes

High performance is required during over 40 thousand hours of operation for practical use of the molten carbonate fuel cell in power generation systems. In order to achieve such performance, the cathode pore structure design which defines the cathode polarization must be optimized. A polarization model for the cathode reaction has been investigated to understand the relationship between the pore size distribution, the electrolyte fill level, and the polarization. The electrodes with smaller pore diameter have smaller polarization and a wider suitable electrolyte fill level due to their larger reaction surface areas. The reaction current profile in the suitable electrolyte fill level is determined by the balance of the ionic resistivity and the reaction surface area.