Elucidation of the degradation factor distribution in one cell on Polymer Electrolyte Fuel Cells

通过对单个细胞在PEFC上的降解因子分布的分析，提出的诊断方法适用于四向细胞的原型。因此，电流扫描方法存在多个问题，即由于每个分段电极的内阻差异，对瞬态响应影响较大，并且电流扫描时，实际电极中的电流密度分布不能反映在诊断结果中。因此，将当前的扫描诊断方法改为不受上述影响的当前中断诊断方法。因此，可以识别出膜干燥/潮湿条件下产生的阻力参数，以及分离器与气体扩散层之间的接触条件。此外，这种改进的诊断应用于细胞在气流方向上的四切。因此，由于第2 /3 RC回路产生的参数变大，第1 RC回路产生的参数变小，在靠近氢、氧等反应物消耗的出口附近，如果提高上述诊断精度，改进后的诊断方法可以阐明PEFC上单个电池的降解因子分布。

The degradation factor distribution in one cell on PEFC was elucidated by which the proposal diagnostics apply to the prototype of quadrisection cell. As a result, the current sweep method had several problems that transient response was greatly influenced according to the difference of internal resistance in each segmented electrode, and the current density distribution in an actual electrode cannot be reflected in the diagnostics result when the current was swept. Therefore, the diagnosis was changed from the current sweep method to the current interruption method of not receiving the above-mentioned influence. As a result, the parameters of the resistance, which originated in the drying/humid condition of membrane, and the contact condition between the separator and the gas diffusion layer, can be identified. Moreover, this improved diagnostics was applied to the cell quadrisected in direction of gas flow. As a result, because the parameter originated in the 2nd/3rd RC circuit becomes large and the parameter originated in the 1st RC circuit becomes small near outlet where reactants such as hydrogen and oxygen are consumed, the degradation factor distribution in one cell on PEFC can be elucidated by the improved diagnostics if the above-mentioned diagnostics accuracy can be improved.