Equivalent model and parameter identification of lithium-ion battery

Abstract

Lithium-ion batteries have been widely used on account of their properties such as high voltage grade, high specific energy, low self-discharge rate, long cycle life, pollution free, and no memory effect. Lithium-ion battery equivalent model plays an important role in studying charging, discharging, and capacity of lithium-ion battery. Reasonable battery model can fully characterize its external features, and the model parameters can reflect its performance state through system identification method. This article adopted the improved second-order dynamic battery model to simulated battery charging and discharging performance in three different working conditions, used the recursive least squares algorithm to identify model parameters, verified the identification result through simulation experiments. The results indicate that the second-order dynamic lithium-ion battery model parameters can effectively simulate charging and discharging process, contribute to reflect the battery performance status, provide support for the efficient management and application of lithium-ion battery.