SOLID OXIDE FUEL CELL OPERABLE AT DECREASED TEMPERATURE USING LaGaO_3 PEROVSKITE OXIDE ELECTROLYTE

摘要

LaGaO_3-based perovskite oxide doped with Sr and Mg exhibits wholly ionic conduction over a wide oxygen partial pressure. In this study, SOFCs where LaGaO_3-based perovskite type oxide is applied as the electrolyte, were studied for the decreased temperature solid oxide fuel cells. The power generation characteristics of cells were strongly affected by the electrode, both anode and cathode. It became clear that Ni and LnCoO_3(Ln:rare earth) are suitable for anode and cathode, respectively. Rare earth cations in the Ln-site of Co-based perovskite cathode also have a great effect on the power generation characteristics. In particular, a high power density could be attained in the temperature range from 973 to 1273 K by using a doped SmCoO_3 for the cathode. The maximum power density of the SOFC, which consisted of Ni anode and Sm_(0.6)Sr_(0.4)CoO_3 cathode attained a value as high as 0.44 W/cm~2 at 1073 K.