Research on Active Equalization Strategy of Retired Lithium Battery Based on Support Vector Machine

Since the retired lithium batteries have been used for a long time, there are great differences in the voltage, State of charge (SOC) and internal resistance of the single battery, and the inconsistency of the battery pack in the operation process can be better solved by the equalization circuit. At present, the commonly used equilibrium strategies have the problems of long equilibrium time and low equilibrium efficiency. Therefore, this paper takes the bidirectional flyback circuit as the topological structure, and proposes a series lithium-ion battery pack active balancing strategy based on the support vector machine (SVM). The battery voltage is taken as the variable to group, and the battery voltage and SOC are taken as the variable to carry out the energy transfer according to the mean method. By building six 18650 series battery pack test platform to carry out the verification experiment of the balancing strategy, the experimental results show that the designed balancing strategy has been greatly improved in balancing time and efficiency.