Materials for high-temperature fuel cells

Abstract

The materials incorporated into molten carbonate fuel cells (MCFC) have remained unchanged over the past 20 years. Materials selection is dominated by the need to satisfy performance, cost and stability criteria in the aggressive environment provided by the molten carbonate electrolyte. Accordingly, materials developments associated with the MCFC have been focused on reducing fabrication costs and improving reliability over extended periods. In contrast, materials selection for solid oxide fuel cells (SOFC) is still a very active endeavour due to the different requirements arising from the range of operating temperatures (500-1000 °C), various design configurations and market opportunities. It is expected that electrode-supported thick-film electrolyte technology will satisfy most of the technical requirements, and investigations are urgently required to reduce the associated fabrication costs, and to provide relevant thermomechanical property data. SOFC systems operate on a variety of fuels, and their relative simplicity makes them particularly promising candidates for small-scale combined heat and power applications, and for incorporation into electric vehicles.