A solution to the anode-electrolyte interaction problem in Lanthanum Gallate fuel cells

摘要

Doped LaGaO_3 has higher conductivity than yttria stabilized zirconia and is stable to perovskite electrodes which may yield improved overall performance of solid oxide fuel cells. However, interdiffusion of nickel from the anode into the LaGaO_3 electrolyte during sintering and subsequent reduction results in a reaction product at the interface which has high resistivity to ionic transport. When a porous layer of electrolyte is sandwiched between the anode and electrolyte layers, the fuel cell performance improves significantly because the porosity in the layer creates available sites for the anodic reaction in the barrier layer. Maximum power density at 800 °C increases from 35 to 350 mW/cm~2 after addition of a 30 μm thick porous electrolyte layer. Scanning electron microscope and impedance studies were employed to characterize the layer and the interfaces.