PEMFC电堆水管理技术的阻抗谱分析

Impedance spectrum analysis of water management technology in PEMFC stacks

建立了三级质子交换膜燃料电池(PEMFC)电堆的等效电路,在不同进气的相对湿度和电流工况下对PEMFC电堆进行电化学阻抗谱(EIS)测试,以分析PEMFC电堆内部水状况、提取膜干和水淹故障的典型特征。结果表明,采用的R(RC)(RC)电路具有物理意义且拟合效果较好,能够反应电堆不同工况的阻抗变化。电堆发生膜干故障的主要特征是出现较高的欧姆阻抗和传荷阻抗,发生水淹故障时则会出现较大的传质阻抗。

An equivalent circuit of a three-cell proton exchange membrane fuel cell(PEMFC)stacks was built.In order to analyze the typical characteristics of the internal water condition,extract the feature of drying and flooding failure for the stacks,the electrochemical impedance spectrum(EIS)tests were conducted on the stacks under different relative gas humidity and current conditions.The results show that the adopted R(RC)(RC)circuit has physical significance and can fit the experimental data well,and reflects the impedance changes in different working conditions of the stacks.The main feature of membrane drying failure is the reactor with high ohmic impedance and charge impedance,and high mass transfer impedance during flooding failure.