Direct current internal resistance decomposition model for accurate parameters acquisition and application in commercial high voltage LiCoO2 battery

Abstract

Accurate modeling and simulation of lithium-ion batteries are beneficial to predict the battery performance. However, the acquisition and verification of parameters are still the main factors that determine the accuracy of the model simulation results. In this paper, direct current internal resistance (DCR) is systematically decomposed differ from the timescale response characteristics and thus DCR decomposition model is constructed. The numerical expressions and the key parameters of different resistances components are reasonably evaluated. Based on the estimated original results, a series of parameters are successfully collected and the strong correlation to DCR is further defined. When applied the proposed DCR model to a commercial high voltage 4.45 V LiCoO2 pouch battery, the simulated results can well match with the experiments, implying the workable of this strategy. This paper shed light on guiding electrochemical parameters design, especially for high energy-density commercial batteries.