ELECTRODE POLARIZATION IN ANODE-SUPPORTED SOLID OXIDE FUEL CELLS

摘要

In this manuscript, both activation and concentration polarizations at the two electrodes of a solid oxide fuel cell (SOFC) are discussed. The main focus of the work was on the fabrication and characterization of anode-supported SOFC with Ni + YSZ (yttria-stabilized zirconia) as the anode, YSZ as the electrolyte, and a perovskite (LSM (Sr-doped LaMnO_3) or LSC (Sr-doped LaCoO_3)) + solid electrolyte (YSZ or doped ceria or LSGM (Sr and Mg-doped LaGaO_3)) as the composite cathode. With hydrogen-air, maximum power densities in excess of 1.5 W/cm~2 at 800°C have been demonstrated on button cells at low fuel utilization. The power density, however, rapidly decreases with decreasing temperature. At ～ 800°C, the largest voltage loss is attributed to the cathode. This loss increases with decreasing temperature, suggesting this to be one of the primary areas of future work. In this manuscript, procedure for the fabrication of anode-supported SOFC is described, and representative test data are presented.