CR传输线模型解析AgO-Zn电池阻抗谱

Interpretation of Electrochemical Impedance Spectroscopy (EIS) of AgO-Zn Batteries by CR Transmission Lines Model

电化学阻抗谱(EIS)是研究电池的重要技术之一,但需要合适的解谱方法才能提取有效信息。本文以文献中Ag-Zn电池的阻抗谱拟合数据为例,说明根据普适性CR传输线模型可得到原作者预言存在却无法证实的结果:存在与电池荷电量(SOC)有直线关系,并在SOC=0.4发生转折的参数。结果还表明这种参数有多个,分别与Ag正极的半导体特征,以及放电过程中控制步骤的变化有关,充分显示了EIS信息丰富的特点。本方法结果客观、具有可操作性,因而有重要的理论意义和应用价值。

The electrochemical impedance spectroscopy（EIS） was one of the most important techniques to study batteries.But the inconsistent models for EIS data interpretation influenced its results＇ objectivity,and severely restricted its independent application.Rehandling EEC parameters of AgO-Zn batteries in literature by CR transmission lines model（CRM） showed that the predicted results could be confirmed,in which the plots of some parameters in CRM versus SOC gave straight lines with turning point at SOC=0.4.The physical meanings of these parameters can be explained in terms of processes resistance,space of charge in semiconductor,as well as the diffusion of OH-from region of Ag electrode to Zn electrode becoming the rate-limiting step at SOC=0.4.The method presented were impersonal and enforceable,with significant value in theoretic and appliance.