| Cost and life cycle considerations require improvement of present cell materials or development of new materials before the molten carbonate fuel cell (MCFC) can compete with combustion based generation systems. The metals and alloys commonly used as structural materials in the MCFC are studied by means of electrochemical techniques under open circuit or polarization, identify the corrosion mechanism and products of MCFC components, in particular, the separator plate. To understand the mechanism of corrosion in a molten carbonate environment, it is necessary to recognize distinct regions of corrosion and investigate them accordingly. In a half-cell study, the corrosion mechanism at the meniscus will be different from that at the totally immersed part of the sample as well as at the thin-film covered part. Each of the above cases corresponds to a different region in a fuel cell or fuel cell stack, and study of these distinct cases requires different interpretations of the commonly used measurements which are found in the literature. Electrochemical measurements show significant differences in corrosion behavior between completely submerged samples and samples covered by a thin carbonate film. |
