Charging strategy optimization for Li-ion batteries based on thermal safety constraints

Fire accidents in lithium-ion battery energy storage systems have occurred frequently in latest years. In order to avoid accidents such as fire, the thermal safety of the battery must be guaranteed during its operation. This paper constrains the battery maximum charge current from the perspective of temperature control to ensure the thermal safety. Firstly, the simplified electrochemical thermal coupling model of lithium-ion battery is constructed. Based on the above model, the determination of parameters in the PID temperature control algorithm was completed using a genetic algorithm. At last, the experimental platform was constructed to examine the effectiveness of the temperature control algorithm. The optimized average charging current is 35.24 A, and the time based on the charging strategy is 55 minutes and 43 seconds. The battery temperature in the whole charging process is kept near the set value, the maximum temperature error is 0.5°C, and the steady-state error is 0.3°C.