Toward developing accelerated stress tests for proton exchange membrane electrolyzers

Abstract

Proton exchange membrane water electrolysis (PEMWE) is technically the most suitable technology for the production of green hydrogen on a large scale. Although it is still more expensive than hydrogen produced from fossil sources, it has already been commercialized. Novel components with cost-effective materials and efficient manufacturing processes are being rapidly developed. However, these components must endure durability tests that can guarantee a lifetime of at least 50,000 operation hours. Consequently, there is an urgent need to develop accelerated stress test (AST) protocols based on a deep understanding of degradation mechanisms and ageing of stack components. Recent reports show that the main degradation mechanisms are associated to anode catalyst dissolution, membrane chemical decomposition and formation of semiconducting oxides on the metal components. These mechanisms can be accelerated by stressors such as high current density, dynamic operation and shutdown modes. Based on these reports and knowledge of the operational requirements for large scale PEMWEs, we propose an AST protocol for the fast evaluation of newly developed components that are expected to be cost-effective and more durable than the state of the art.