Induced Hydrogen Crossover Accelerated Stress Test for PEM Water Electrolysis Cells

Polymer electrolyte membrane water electrolysis (PEMWE) is considered a promising solution for decarbonizing industry and establishing a sustainable hydrogen infrastructure. The central components of a PEMWE cell are represented by the membrane electrode assembly (MEA), comprising a polymer electrolyte membrane (PEM) integrated with catalyst layers (CLs) and porous transport layers (PTLs) for diffusion transport of water- and gases. The Nafion-based PEM is the weakest element of this system, susceptible to both chemical and mechanical degradation. Chemical degradation of the membrane occurs when hydrogen peroxide forms due to the crossover of product gases (H2 and O2) 2.
In this work, membrane failure due to induced hydrogen crossover has been addressed in a membrane-focused accelerated stress test (AST). The AST was conducted on a test cell employing asymmetric H2O and gas supply in open circuit voltage (OCV) mode, at two different temperatures (60 °C and 80 °C). Electrochemical characterization was performed at the beginning- and end of the testing period, revealing a 1.6-fold higher increase in high- frequency resistance (HFR) at 80 °C. The extent of hydrogen crossover was measured using a micro-GC, while the fluoride emission rate (FER) as indicator for membrane degradation was continuously monitored during the ASTs1. A direct correlation between FER and H2 crossover was established, confirming accelerated membrane degradation at higher temperatures.

This research is performed under the HyLife project (K-Project HyTechonomy, FFG grant number 882510) which is supported by the Austrian Research Promotion Agency (FFG).

1. Kuhnert, E., Heidinger, M., Sandu, D., Hacker, V. & Bodner, M. Analysis of PEM Water Electrolyzer Failure Due to Induced Hydrogen Crossover in Catalyst-Coated PFSA Membranes. Membranes 13, 348 (2023).
2. Kuhnert, E., Hacker, V. & Bodner, M. A Review of Accelerated Stress Tests for Enhancing MEA Durability in PEM Water Electrolysis Cells. International Journal of Energy Research 2023, 1–23 (2023).