Spatiotemporal Decoupling of Water Electrolysis for Dual-Use Grid Energy Storage and Hydrogen Generation
Daniel Frey, Jip Kim, Yury Dvorkin, Miguel A. Modestino
Abstract
The implementation of electrolysis systems for electrochemical hydrogen production has continued to grow as the paradigm shift toward renewable energy and fuels progresses. However, issues regarding conventional polymer electrolyte membrane (PEM) electrolyzers remain; their performance can be affected when operated with intermittent energy sources due to gas crossover, while the high cost of electricity continues to hinder large-scale adoption of the technology. To make electrochemical hydrogen production more competitive, renewable energy sources need to be used with new strategies for electrochemical hydrogen production. Here, we show a cerium-mediated decoupled electrolysis system that produces hydrogen and stores energy in the redox couples. We present electrochemical studies to observe the effects of diffusive transport, convective transport, and thermal effects. Following this, a technoeconomic analysis is done, focusing on the optimization of the system operation and the identification of target operation parameters to achieve hydrogen production at a competitive price.