Abstract：The response characteristics of linear sweep voltammetry (LSV) were used to develop an equivalent circuit model of a proton exchange membrane (PEM) fuel cell to distinguish the various electrochemical processes, including hydrogen desorption on the platinum, charging of the double-layer capacitance, electron internal short circuits and hydrogen crossover. This model eliminated the effect of the scan rate on the LSV results so that the hydrogen crossover current and membrane electronic resistance could be measured. A galvanostatic method was also used to measure the hydrogen crossover current and the electronic resistance. Measurements on a single cell with an active area of 34 cm2 with the LSV method show that the hydrogen crossover current is 1.19 mA·cm-2 and the electronic resistance is 479 Ω·cm2 while the galvanostatic measurements give the hydrogen crossover current of 1.25 mA·cm-2 and the electronic resistance of 413 Ω·cm2. This model can be used to analyze various electrochemical measurements in PEM fuel cells with the two methods giving complementary measurements for various PEM fuel cell processes.
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