Starvation, flooding, and dry‐out phenomena occur in polymer electrolyte membrane fuel cells (PEMFCs), due to heterogeneous local conditions, material inhomogeneity, and uneven flow distribution across the single cell active area and in between the individual cells. The impact of the load level and air feed conditions on the performance was identified for individual single cells within a 10‐cell stack. Analysis of the current density distribution across the active area at the cell level was correlated with electrochemical impedance spectroscopy to enable operando fault diagnostic without any impact of the applied analytical tools on the single cell behavior. Moreover, the combination of both technologies allows in‐depth analysis of fault mechanisms in fuel cell single cells with improved sensitivity. Current density distribution and the quantitative assessment of the performance homogeneity demonstrated high sensitivity to small humidity changes and allow the detection of critical events, such as dry‐out in single cells. Impedance analysis is more sensitive regarding polarization and diffusion limitations and allows detection of cell flooding. The combination of both techniques is required for reliable identification of air starvation faults.

中文翻译：

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通过评估局部性能和单元阻抗分析对PEMFC电池堆进行故障诊断

聚合物电解质膜燃料电池（PEMFC）中会出现饥饿，溢流和变干现象，这是由于局部环境不均匀，材料不均匀以及单个电池活动区域之间以及单个电池之间的流量分布不均匀所致。对于10节电池堆中的单个单节电池，确定了负载水平和供气条件对性能的影响。在细胞水平对整个活动区域上电流密度分布的分析与电化学阻抗谱相关联，以实现操作故障诊断，而不会影响所应用的分析工具对单电池行为的影响。此外，两种技术的结合可以以更高的灵敏度深入分析燃料电池单电池的故障机制。电流密度分布和性能均质性的定量评估表明，对小湿度变化具有高度敏感性，并允许检测关键事件，例如单细胞干燥。阻抗分析对极化和扩散限制更为敏感，并允许检测单元泛洪。为了可靠地识别空气饥饿故障，需要将两种技术结合起来。