Review of High-Temperature Fuel Cell Hardware Materials

The high-temperature carbonate fuel cell is an ultra-clean and high-efficiency power generator. Its intermediate operating temperature, ∼600–650°C, is considered optimum to facilitate fast fuel cell reaction kinetics, utilize waste heat efficiently in a combined heat and power or bottoming power cycle, and at the same time allow use of commercial commodity materials for cell hardware and balance-of-plant (BOP) piping/equipment construction. MW size power plants manufactured by FCE are being operated at customer sites throughout the world. The cell hardware and BOP materials selections are founded on many years of focused research. Microstructure and mechanical property evolution, oxidation, hot corrosion and carburization have been extensively investigated. Long-term subscale stack endurance as well as power plant field operation results to date show that the baseline hardware construction materials meet the endurance goals. Material durability is well understood and solutions are available to further extend life. This paper will review durability experience of hardware materials (cell, stack and BOP).