Membrane electrode assemblies (MEA) for polymer electrolyte membrane fuel cells (PEMFC) may possess as‐manufactured non‐uniformities in any of its constituent components. This work studies casting irregularities located within the PEM to understand their potential impact on MEA initial performance. Membrane material was cast on a lab‐scale polymer casting line operating either within or at the boundaries of the process window. The resulting membrane material was either pristine in the former case, or, in the latter case, contained air bubbles, cracks, and other irregularities, ranging in size from about 0.6 to 3 mm. Spatial polarization experiments were conducted using a 121‐channel segmented fuel cell system, and thermal imaging was performed subsequently to map hydrogen crossover to spatial performance. While total‐cell polarization data was minimally impacted by the irregularities, the spatial diagnostics showed local performance impacts that, in operation over time, could cause degradation in performance or earlier failure of the MEA. Such impacts could lead to these irregularities being classified as defects, i.e., manufacturing variations that should be identified and not included in a fuel cell stack. Classification of irregularities as defects will ultimately assist the industry by contributing to the development of threshold detection limits for in‐line quality control diagnostics.

中文翻译：

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膜铸件不规则对初始燃料电池性能的影响

用于聚合物电解质膜燃料电池（PEMFC）的膜电极组件（MEA）可能在其任何组成组件中具有制造不均。这项工作研究了位于PEM内的铸件不规则，以了解它们对MEA初始性能的潜在影响。膜材料是在实验室规模的聚合物浇铸线上浇铸的，该生产线在工艺窗口之内或之内运行。所得的膜材料在前一种情况下要么是原始的，要么在后一种情况下包含气泡，裂缝和其他不规则性，尺寸范围为约0.6至3mm。使用121通道分段式燃料电池系统进行了空间极化实验，随后进行了热成像以将氢交叉映射为空间性能。尽管总细胞极化数据受不规则性的影响最小，但空间诊断显示局部性能影响，随着时间的流逝，可能会导致MEA性能下降或更早失效。这样的影响可能导致这些不规则现象被归类为缺陷，即应识别且不包括在燃料电池堆中的制造偏差。将不规则分类为缺陷将最终通过为在线质量控制诊断开发阈值检测极限做出贡献，从而最终为行业提供帮助。这样的影响可能导致这些不规则现象被归类为缺陷，即应识别且不包括在燃料电池堆中的制造偏差。将不规则分类为缺陷将最终通过为在线质量控制诊断开发阈值检测极限做出贡献，从而最终为行业提供帮助。这样的影响可能导致这些不规则现象被归类为缺陷，即应识别且不包括在燃料电池堆中的制造偏差。将不规则分类为缺陷将最终通过为在线质量控制诊断开发阈值检测极限做出贡献，从而最终为行业提供帮助。