Low Temperature Regenerative Solid Oxide Fuel Cell

Technology Management, Inc. (TMI) proposes to apply its knowledge of high temperature reversible (also called regenerative) solid oxide fuel cell (SOFC) electrolyzer devices and lower temperature electrolyte and electrode materials to develop a lower temperature, reversible fuel cell electrolyzer system with improved system life. The feasibility of high temperature (1000-950oC) reversible operation was demonstrated previously by TMI in single cells and short stacks under NASA-funded research efforts. Long life (targets of >20,000 hours, >30,000 cycles for orbital applications) was identified as an important technical challenge. TMI has demonstrated increased life in fuel cells by decreasing operating temperature from between 1000 and 950oC to 800oC. Achieving good electrochemical performance at lower temperatures requires either a thinner YSZ electrolyte or the substitution of an alternate solid electrolyte material, i.e., LaGaO3. However, neither material has been tested by TMI in reversible fuel cell/electrolyzer operation. TMI will demonstrate the feasibility of using these materials in low temperature, reversible fuel cell electrolyzer operation in Phase I leading to lower temperature stack and system operation with reduced degradation rates in a larger demonstration system in Phase II.