Intermediate Temperature Solid Oxide Fuel Cell Using Ni Doped LaGaO3 Electrolyte

Abstract

Although the hole conduction appeared, it was found that doping by Ni is effective for improving the oxide ion conductivity in La0.8Sr0.2Ga0.8Mg0.2O3. Considering the ionic transport number and the electrical conductivity, the optimized composition for Ni doped sample was La0.8Sr0.2Ga0.8Mg0.13Ni0.07O3 (LSGMN). In agreement with the improved electronic conductivity, power density of the solid oxide fuel cell using LaGaO3 electrolyte increased by doping small amount of Ni for Ga site. In particular, the power density of 224 mW/cm2 at 873 K was attained on the cell using LSGMN for the electrolyte in spite of the usage of electrolyte plate with 0.5 mm thickness. In order to develop the inexpensive cathode oxide, effect of aliovalent cation doping for Co site of La0.9Sr0.1CoO3 was further investigated. It was found that the cathodic overpotential decreased by doping Cu for Co site of LaCoO3.