Polymer electrolyte membrane (PEM) water electrolysis is a promising energy storage technology to produce highly pure hydrogen with high efficiency ¹. However, to implement it on a larger scale, it is essential to understand the effects of defects and the required tolerances and quality controls during manufacturing or subsequent handling. Inhomogeneities in membrane electrode assembly (MEA) component materials caused by the manufacturing process or subsequent handling can lead to performance loss and failure ². Defects such as membrane pinholes, cuts, tears, abrasions, or perforations can all potentially impact MEA performance. In terms of impact, a loss of integrity of the membrane can allow bulk gas transport (crossover) and/or electrical shorting ³.

In particular, hydrogen crossover is a crucial issue for PEM water electrolysis in terms of safe operation and efficiency losses, especially at increased hydrogen pressures. Crossover reduces the overall efficiency of the system and poses flammability hazards under certain conditions ⁴. Pinholes that form during the manufacturing process or during operation through degradation of the membrane lead to dramatically increased hydrogen crossover.

In this study, the impacts of membrane pinholes on the performance and hydrogen crossover of PEM water electrolyzer cells are studied. Pinholes with different sizes are artificially introduced to the MEA to investigate the effects on the initial cell performance and hydrogen crossover rate under various backpressure and current density conditions.

Reference

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