STATE OF CHARGE ESTIMATION OF LITHIUM-ION BATTERY
USING ENERGY CONSUMPTION ANALYSIS |
Shan Chen 1, Tianhong Pan 2, Bowen Jin 1 |
1School of Electrical and Information Engineering, Jiangsu University 2School of Electrical Engineering and Automation, Anhui University |
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ABSTRACT |
The traditional electric current integral algorithm cannot accurately estimate a lithium-ion battery’s state of
charge (SOC) under complex discharge conditions. Therefore, in this study, a new estimation method based on a power
integral algorithm is proposed. First, the first-order Thevenin equivalent circuit model is selected, and the energy storage and
loss of the lithium-ion battery during charging and discharging operations are analyzed. Second, the inherent disadvantages of
the electric current integral algorithm are analyzed, and an SOC estimation based on the power integral algorithm is presented.
The error correction for the SOC estimation is derived using the extended Kalman filter (EKF). Using the established test
bench, the effects of environmental temperature, state of health, and current density on the SOC estimation are analyzed. The
experimental results show that the proposed method combining the power integral and EKF can accurately estimate the SOC
of a lithium-ion battery. |
Key Words:
Electric current integral algorithm, Thevenin equivalent circuit model, Extended Kalman filter, State of
charge estimation, Power integral algorithm |
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