Fuel cell including a cathode comprising a sub phase composed of tricobalt tetroxide

摘要

A fuel cell includes an anode, a cathode and a solid electrolyte layer. The cathode has a main phase and a sub phase. The main phase is composed of a perovskite type oxide including cobalt. The sub phase is composed of tricobalt tetroxide. The solid electrolyte layer is disposed between the anode and the cathode. An area occupancy of the sub phase in a sectional surface of the cathode is equal to or less than 9.8%.