用EIS研究PEMFC膜电极的运行条件对其性能的影响

在质子交换膜燃料电池（PEMFC）中，采用电化学阻抗谱（EIS）研究了膜电极（MEA）的一些运行条件对其工作性能的影响，并探讨了其作用机理．通过测量数据的解析和等效电路的数学模拟，得到了与MEA结构关联的电极诸参数随电池温度和反应气体压力的变化规律．研究表明，MEA的氧电极的电化学反应电阻随电池温度的升高显著减小，氧电极的双电层电容随电池温度的升高有所增加，表明电极有效面积得以增加，有利于MEA工作性能的提高．

Effects of Operating Conditions for Membrane Electrode Assembly in PEMFC on Its Performance by EIS Technique

Effects of some operating conditions of membrane electrode assembly (MEA) in proton exchange membrane fuel cell (PEMFC) on its working performance were investigated by electrochemical impedance spectroscopy (EIS) technique. Its mechanism was also discussed in this paper. Through the analysis of measured data and mathematical simulation of equivalent circuit, variation of electrode parameters related to the structure of MEA with cell temperature and reactant gas pressure was obtained. Results show that electrochemical reaction resistance of oxygen electrode in MEA decreases evidently when cell temperature increases, while double layer capacitance of oxygen electrode increases when cell temperature increases. This trend indicates enhancement of effective area of the electrode, which is favorable for the improvement of the working performance of MEA.