SOLID OXIDE ELECTROLYSIS CELL, AND METHOD AND SYSTEM FOR OPERATING SAME

A method for operating a solid oxide electrolysis cell which can suppress degradation of the hydrogen electrode, is provided. A method for operating a solid oxide electrolysis cell includes a hydrogen electrode, an oxygen electrode, and an electrolyte layer sandwiched between the hydrogen electrode and the oxygen electrode. The hydrogen electrode includes a catalyst layer structured with Ni-containing particles dispersed and supported on a porous mixed ionic and electronic conducting oxide. The method includes an alternating operation in which a water vapor electrolysis operation and a fuel cell operation are repeated alternately.