液流电池理论与技术——电化学阻抗谱技术原理和应用

Principle and application of electrochemical impedance spectroscopy method

电化学阻抗测定技术是一种研究电极反应动力学和电化学体系中物质传递与电荷转移的有效方法,通过电化学阻抗数据所提供的信息,能够分析电极过程的特征,包括动力学极化、欧姆极化和浓差极化,为电化学过程设计、电极材料开发和电极结构研究提供基本依据。本文在介绍电化学阻抗谱技术原理的基础上,分别以液流电池、空气扩散电极过程为对象,阐述电化学阻抗谱中电荷转移、物质传递等过程以及多孔电极本身的电荷传递电阻等,并综述阻抗技术在设计电池结构、优化电极材料等方面的应用实例。

Electrochemical impedance spectroscopy （EIS） method is effectively used to analyze the kinetic and diffusion features in electrode process. Based on the expermental data, the individual electrochemical step can be analyzed from the electrode polarization processes including charge transfer resistance, concentration polarization resistance, and ohmic resistance, which is a key factor for the design of an electrode. The principles of EIS including the kinetics, mass transfer performances and the distributed resistances inside the porous electrode are introduced by taking a gas diffusion electrode and redox flow batteries as the examples. Moreover, applications of EIS method on the optimization of porous electrodes are also reviewed.