What is the SOC calibration point for lithium-ion batteries?

It can be found that the SOC absolute errors of two lithium-ion batteries can be limited in a narrow SOC error band of 0.1%, which suggests that the mean value can be considered as the SOC calibration point to correct the initial SOC value.

How to estimate state of charge of lithium-ion battery?

A data-driven coulomb counting method is proposed to estimate state of charge (SOC) of lithium-ion battery. The incremental capacity analysis method without filtering process is applied to calibrate the initial SOC value. The Gaussian process regression (GPR) method is used to calibrate the actual capacity.

Can data-driven coulomb counting method be used in lithium-ion batteries?

The feasibility and robustness of the proposed methods are verified with two lithium-ion batteries under fast capacity degradation, and the validation results indicate that the data-driven coulomb counting method can calibrate the initial SOC and actual capacity, realizing the on-line accurate SOC estimation both in charging and discharging stage.

Why is calibration important for coulomb counting method?

Hence, the calibration method can effectively correct the initial SOC and actual capacity to improve the estimation accuracy of coulomb counting method. Accurate SOC estimation is crucial for BMS to ensure the reliability and safety of battery operation during EVs driving process.

How do you calibrate SDM wire resistance?

An in-situ calibration is conducted to correct the voltage drop attributed to wire resistance in SDM. To achieve this, the LIB cells are connected to the test fixture, and the wire resistance of each SDM channel is measured using a low current of 1 mA, followed by a 15-minute resting period.

How accurate is a battery discharging capacity model?

We can see that the relative errors between the real and estimated capacity of battery #1 and #2 are below 2% and 2.5%. The maximum relative errors of two batteries are 1.90% and 2.48%, respectively, indicating that the model can provide accurate online estimation of discharging capacity. Fig. 12.