PNNL

Abstract

With the steady reduction in solid oxide fuel cell (SOFC) operating temperatures into a range of 650-800C, cost effective metallic materials, in particular high temperature oxidation resistant alloys, have become promising candidates, in place of ceramic counterparts, for construction of interconnects in SOFC stacks. For a lifetime of thousands of hours, the alloys must demonstrate excellent surface, structural and electrical stability, and compatibility with other components in SOFC stacks in a very challenging environment. The paper provides a comprehensive critical review of metallic interconnects for SOFCs with a focus on recent progress in materials development, as well as advances in understanding materials degradation and interfacial phenomena under the SOFC operating conditions. It also attempts to provide guiding principles for development of optimized, cost-effective metallic interconnect materials that can demonstrate satisfactory life-time stability and performance.