A new SOC estimation algorithm without integrated error using DCIR repetitive calculation

In this paper, the State of Charge (SOC) estimation algorithm is proposed using the Direct Current Internal Resistance (DCIR) repetitive calculation, which reflects the renewed Open Circuit Voltage (OCV) in real-time by using the measured DCIR through the constant current injection method. Therefore, it is possible to improve the estimation error because there is no integration error and reset interval. Finally, the performance of the proposed method is evaluated by comparing with the estimated SOC result using the Coulomb-Counting method under the various C-rates experimental conditions. Also, a State of Health (SOH) estimation method using measured DCIR and Extended Kalman filter (EKF) is proposed. The accuracy of estimation method is evaluated by MATLAB simulation results.