温度对质子交换膜燃料电池阻抗特性的影响研究

使用电化学阻抗谱设备测试不同温度条件下的质子交换膜燃料电池阻抗谱曲线,并运用RL(QR)等效电路分析了电池温度和加湿温度对电化学阻抗的影响。研究结果表明:当电池温度高于加湿温度时,欧姆阻抗和法拉第阻抗都显著增加;等效电路中常相位角元件表征双电层特性的n值大于0.5,表明质子交换膜燃料电池中双电层的阻抗值偏重于容抗特性,同时加湿温度高出电池温度越多,双电层体现为容抗特性的程度越明显。

Effect of Temperature on Impedance Characteristics of Proton Exchange Membrane Fuel Cell

The impedance spectra curve of proton exchange membrane fuel cells (PEMFC) at different temperatures was obtained by using an electrochemical impedance spectroscopy (EIS) tool, and the effects of cell temperature and humidification temperature on electrochemical impedance were analyzed by RL(QR) equivalent circuit. It is found that both ohmic impedance and the Faraday impedance increase significantly when the cell temperature is higher than the humidification temperature. The n value of the constant phase angle element in the equivalent circuit that model the behavior of a double layer is greater than 0.5, which means that the resistance of the electrical double layer in PEMFC is prone to be the capacitive reactance. Besides, the higher humidification temperature is than cell temperature, the more obvious capacitive reactance the electrical double layer presents to be.