The Promise and Challenges of Intermediate Temperature Fuel Cells

Abstract

An intermediate temperature range of 200 to 500 oC has received less attention in fuel cell research than higher and lower temperature fuel cell systems due to the relatively few number of electrolytes that operate in this range. However materials research over the past 15 years has resulted in new electrolytes with sufficiently high ionic conductivity to enable intermediate temperature fuel cells (ITFCs). The focus of the Reliable Electricity Based on ELectrochemical Systems (REBELS) program at the U.S. Department of Energy Advanced Research Projects Agency-Energy (ARPA-E) is to create ITFCs with the potential for drastically reduced system costs, as well as enhanced electrochemical functionality. These systems are expected to have benefits compared to higher and lower temperature operation, though they will also encounter new challenges such as methane reforming, ohmic resistance of the electrolyte, and electrode overpotentials at temperatures less than 700 oC.