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arXiv · 2606.25992

Poisoning effect of ammonia on the performance and transport process of proton exchange membrane fuel cells

Abstract

Ammonia is a high-density hydrogen energy carrier and can be decomposed to produce hydrogen for use in fuel cells. However, a significant challenge in ammonia-decomposition-based fuel cell applications is the unavoidable presence of trace ammonia impurity, which can poison the fuel cell, but the poisoning mechanism remains unclear. To address this, a three-dimensional numerical model of proton exchange membrane (PEM) fuel cells with ammonia impurities is established to explore the transport process and underlying poisoning mechanism. The influences of key factors, including ammonia concentration, operating temperature, operating humidity, and membrane thickness, are studied. The poisoning mechanism is analyzed from the perspectives of the distributions of proton conductivity, current density, and dissolved water content. The results show that ammonia diminishes the cell performance by substantially reducing the proton conductivity of both the PEM and the anode catalyst layer. Higher operating temperatures and higher operating humidity can alleviate ammonia poisoning. Decreasing the membrane thickness can also help to mitigate ammonia poisoning, but may lead to less uniform current distribution.

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Yaxian Han, Wei Gao, Yichao Huang, Tianyou Wang, Zhizhao Che. 2026-06-24. Poisoning effect of ammonia on the performance and transport process of proton exchange membrane fuel cells. https://arxiv.org/abs/2606.25992

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