PERFORMANCE IMPROVEMENTS OF MOLTEN CARBONATE FUEL CELLS AND STACKS APPLYING Li/Na ELECTROLYTE

摘要

Molten Carbonate Fuel Cell (MCFC) is one of the most promising power generation technology, which can utilize coal as fuel with very high efficiency. Application of Li/Na carbonate as the electrolyte of MCFC is expected to achieve higher voltage and longer life by its higher ionic conductivity and lower solubility of NiO cathode. Many bench scale single cells adopted with Li/Na electrolyte have been tested and their performance has been improved. The high voltage has been mainly caused by reducing internal resistance and cathode overvoltage. The Li/Na cell has several times longer life limited by nickel short-circuiting than that of Li/K cell. Deposited nickel distribution was measured and deposition phenomena is estimated. The 10 kW-class stack consists of Li/Na cells has been operated over 8,400 hours among MCFC stacks ever tested under pressurized condition, aiming over 10,000 hours' operation.