A New Method for Fractional Order Model Parameters Identification of Lithium-ion Battery

Equivalent circuit model (ECM) is a common method to simulate the electrochemical characteristics of lithium-ion batteries (LIBs). Fractional order model (FOM) has been proved to be able to characterize the internal characteristics of the battery more accurately, and the identification of model parameters is an important prerequisite to construct the ECM of LIBs. In this paper, a model parameter identification algorithm based on Beetle Antennae Search-Recursive Least Squares (BAS-RLS) is proposed for the FOM of LIBs. Firstly, the open circuit voltage (OCV) of battery is identified by Rint model. After obtaining the OCV of the battery, the BAS-RLS algorithm is used to identify the parameters of the FOM. The verification of four working conditions of LIBs confirms that the constructed FOM has higher accuracy. The maximum RMSE and MAE of the model output terminal voltage indexes under four working conditions are 9.1783 mv and 7.0939 mv respectively.