用EIS研究PEMFC膜电极的活化机理

为使质子交换膜燃料电池的膜电极达到和发挥其最佳性能,对其进行活化是一种有效方法,变流强制活化对提高膜电极的电化学性能比较理想。用电化学阻抗谱(EIS)对膜电极活化过程机理的研究表明,氧电极在活化过程中电化学反应电阻大大降低,氢电极和氧电极的双电层电容均显著增大,活化过程大大增加了膜电极的电极有效面积,有利于膜电极性能的提高。

Study of activation mechanism of membrane electrode assembly in PEMFC by EIS

To achieve and explore the optimal performance of membrane electrode assembly in proton exchange membrane fuel cell, the activation treatment is one of the effective means, and the effect of activation at varied current is more ideal method for this purpose. In this work, the electrochemical impedance spectrum (EIS) technique was used to understand the mechanism of activation process of membrane electrode assembly. During the activation, it was showed that the electrochemical reaction resistance of oxygen electrode decreased dramatically, and the double layer capacity of both hydrogen and oxygen electrodes increased obviously. The activation process enhanced the effective area of membrane electrode assembly, thus it is favorable to improve the performance of membrane electrode assembly.