Electrochemical Impedance Spectroscopy-Based Dynamic Modeling of Lithium-Ion Batteries Using a Simple Equivalent Circuit Model

As one of the most commonly used models for describing the dynamic voltage response of lithium-ion batteries (LIBs), the equivalent circuit model (ECM) is routinely parameterized using the time-domain experimental data from some dynamic tests. One downside of this time-domain approach is a lack of credible physical interpretation about the model parameters. In this article, a genuine electrochemical impedance spectroscopy (EIS)-based dynamic modeling approach for LIBs is developed, which only uses low-frequency EIS data in parameterization of the ECM. The EIS-based modeling method combines simplicity, high accuracy, and clear physical interpretation. With the EIS-based modeling method, a simple ECM, namely, a serial connection of a resistance (Rs$R_{\text{s}}$), describing Ohmic polarization and interfacial reactions, and an resistance-capacitance parallel branch (Rp//Cp$R_{\text{p}} / / C_{\text{p}}$), describing diffusion polarization, suffice to accurately capture LIB dynamics in most applications.