Influence of steam concentration on the degradation behavior of reversible solid oxide fuel cells

Abstract

The degradation behavior of reversible SOFCs was investigated under various steam concentration atmospheres in the power generation and electrolysis processes. In the power generation process at high steam concentration, a sudden drop in terminal voltage was observed and cell performance degraded. After H2 treatment to the degraded cell, performance recovered but not to the initial level. This result indicated that the irreversible degradation proceeded only partially. On the other hand, during electrolysis, terminal voltage increased continuously while applying a constant current under low steam concentration. This behavior brought about irreversible degradation at both electrodes and suggested interfacial reaction and microstructural destruction.