A team at NAIST has found an improved process to prepare Proton Conductive Ceramic Fuel Cells. PCFC consist of a three-layer sandwich of a ceramic electrolyte membrane, an air electrode and a fuel electrode, and use oxygen and water to generate electricity. Protons (H + ion) permeate through the ceramic electrolyte membrane, thereby operating as a battery. Conventionally, stabilized zirconia of oxide ion conductor has been used as a main component of solid oxide fuel cells SOFC, as a solid electrolyte layer selectively permeable to ions. However, in recent years, it has been found that by switching to a selective proton permeable ceramic membrane the power generation efficiency drastically improved to a power generation efficiency of 75%. However, sintering technology for a practical size of 50 mm square or more had not been developed. The team used a thin layer of BaZrO3 based material on the fuel electrode side and a laminated thin layer of an electron leakage blocker with high proton conductivity on the air electrode side, resulting in good CO2 durability and suppression of electron leakage. Even at a low operating temperature of 600 ° C, the current density was 0.3 A/cm 2 around 0.85 V, superior to SOFC.

NEDO news release, July 4, 2018