Lithium-Ion Battery Model Parameters Estimation Using Equivalent Circuit Model for E-mobility Applications

Abstract

Accurate estimation of battery internal model parameters and consequently SOC prediction is crucial in any battery power system. Hence, it is a fundamental need in electric vehicles, smart grids, and energy storage systems. The accuracy of parameters identification will affect the battery management system, battery safety, characteristics, and performance, which mainly depends on battery model parameters. So, to estimate the parameters accurately and easily, we require effective, simple, and robust parameters estimation algorithms. In this article, we propose a new method for estimation of parameters using least square method algorithm for Lithium-Ion Batteries (LIBs) for Electric Vehicle (EV) applications. In this, a second-order RC equivalent circuit model is considered for estimation of parameters of NMC battery. The estimation of parameters and relation between OCV-SOC nonlinear is obtained from the experimental data. This proposed method shows that the calculation of parameters is fast and efficient.

Equivalent Circuit Model Parameters Estimation of Lithium-Ion Batteries Using Cuckoo Search Algorithm

“…25 These models give crucial data like current, voltage, and SOC, as well as incorporating some nonlinear impacts of the problem while retaining a reasonable level of complexity. 26 Chemical reactions such as charge transfer reactions and diffusion processes are meticulously represented through this model, and each individual chemical reaction is illustrated by a specific electrical component. Another crucial stage in the battery modelling process is to choose an ECM structure that can match simulation and experimental results.…”

“…An ECM is comprised of a DC voltage source that serves as an OCV, ohmic resistance R 0 that is the resistances induced by the electrolyte, current collectors, and the resistance of the Solid Electrolyte Interface (SEI) layer. 26 The first RC parallel pair R 1 , C 1 is responsible for the battery's charge transfer resistance and double-layer capacitance, and it represents the short-time transient response, whereas the second RC parallel branch R 2 , C 2 corresponds to the battery's diffusion process, and it represents the long-time transient response. These all parameters are the functions of SOC, voltage V, current I, and temperature T. 29 The voltages across different regions of the model are described by the following dynamic equations: 4,29…”