(Invited) Development of Standards and Best Practices for Materials Testing in Low Temperature Electrolysis

Abstract

As part of any overall strategy for environmental sustainability, a source of renewable hydrogen is needed, as a chemical feedstock as well as part of the portfolio of energy storage solutions. Currently over 95% of hydrogen is made from fossil fuels through natural gas reforming or coal gasification. However, water electrolysis has decreased significantly in capital cost and increased in scale. At the same time, renewable electricity costs have also dropped, especially in periods of high capacity, providing a potential pathway for competitively priced “green” hydrogen from water splitting. Still, continued materials and manufacturing research is essential to achieve cost parity with fossil fuels and produce renewable hydrogen at scale. As new materials are developed, it is important to make accurate comparisons to a common baseline, to understand the potential for improvement over existing technology and to compare different pathways. Currently, research on electrolysis materials published in the scientific literature tends to be scattered across a range of test conditions and configurations, making these comparisons difficult. For example, catalysts may be tested with a range of membranes, at different temperatures, with different counter electrodes, and different electrolytes. In addition, test configurations can impact performance and cause variation in results even for the same materials. Having a standard baseline set of conditions can ground the results, even if additional tests are also performed to look at benefits of specific conditions for specific materials. There are currently efforts in both Europe and the United States to select common standards and define test parameters and configurations for low temperature electrolysis. The U.S. Department of Energy is funding a team to coordinate similar work across all of the major water splitting pathways: low temperature electrolysis (primarily ion exchange membrane-based), high temperature electrolysis (primarily solid oxide), solar thermochemical water splitting (STCH), and direct photoelectrochemical water splitting (PEC). This talk will describe status of this project, including a workshop held in October 2018 and follow up work for specific materials tests.