State of Charge Effects on the Parameters of Electrochemical Impedance Spectroscopy Equivalent Circuit Model for Lithium Ion Batteries

Abstract

It is essential to know the behavior of the battery at all relevant internal and external conditions when the battery cell is in the new and the aging state. Electrochemical impedance spectroscopy (EIS) is a viable approach that can be used in lithium ion batteries (LIBs) to investigate the electrochemical behavior. In this paper, in order to investigate the state of charge effects on the LIBs, three types of commercial LIB cells were used, and the EIS measurements were performed under 100%, 80%, 50%, 20% and 0% SOC, respectively. An equivalent circuit model (ECM) including two constant phase angle elements in parallel with resistor elements is established to study the impedance characteristics for LIBs. The influence of the state of charge on the parameters of the ECM was analyzed. Based on the results we think EIS combined with ECM simulation tool can be used to derive useful information for improving battery design and state of health prediction.

Effects of Temperature on the parameters of the Electrochemical Impedance Spectroscopy for Lithium-Ion Batteries

“…However, there is no unique correspondence between the electrochemical impedance spectrum and the equivalent circuit, so it is necessary to find an ECM with a high degree of matching between the simulation results and the measurements. Combined with the previous work in the laboratory [14] , this paper selected the equivalent circuit model shown in Figure 1, and the simulation results are in good agreement with the measurements. In Figure 1, L represents the high-frequency inductance, and R s is the sum ohmic resistance of the electrode, electrolyte, separator, and material.…”

“…This change mode is similar to that of NMC batteries. Haiqing Xiao et al [14] proved the considerable significance of SOC to the charge transfer impedance by comparing the EIS spectra of three batteries' impedance under different SOCs at the same temperature. This paper brings in the temperature variable on the basis of previous experiments.…”

Oxide‐based ternary composite solid‐state electrolyte for next‐generation lithium batteries

“…In the equivalent circuit of a solid‐state electrochemical cell with a blocking coating, the series resistance ( R b ) is a parameter that describes the bulk resistance of the cell, including the resistance of the electrolyte layer, the blocking layer, and any interfacial layers or contact resistances between the cell components. R b can be an important factor in determining the performance of the electrochemical cell, as it can affect the rate of ion transport and the efficiency of the electrochemical reactions 59,60 …”

“…R b can be an important factor in determining the performance of the electrochemical cell, as it can affect the rate of ion transport and the efficiency of the electrochemical reactions. 59,60 Plots of ionic conductivities were fitted with an equivalent circuit, as shown in Figure 7A. The R b denotes the bulk resistance, the Z w denotes Warburg impedance, the R gb represents the grain boundary resistance, R ct is charge transfer resistance, while CPE gb and CPE el denote the constant phase elements for grain boundaries and electrodes, respectively.…”

Ultrasound-Induced Impedance Reduction in Lithium Ion Batteries

“…The results were then parameterized using an ECM for NMC/Graphite cells. 16 Specifically, the overall impedance spectrum of a cell was divided into four parts to reflect the established ECMs, 17,18 as shown in Fig. 2.…”