MATERIALS CONSIDERATIONS FOR APPLICATION TO SOLID-STATE ELECTROCHEMICAL DEVICES

An overview of some recent materials-related investigations. aimed at providing a better understanding of their role in enhancement of the performance of high-temperature solid-state electrochemical devices, is given with special reference to solid oxide fuel cells. The limitations of traditional approaches taken to optimize device performance are pointed out and the need to study interactions between materials is emphasized. These considerations arise due to enhanced kinetics at high temperature of interdiffusion and bulk diffusion at solid/solid interfaces which lead to chemical and physical changes at the electrode interfaces. The effect of these changes on device performance and stability arc discussed. Relationships between composition-property and processing-microstructure are also discussed. An impedance model. based upon detailed interface investigations is presented.