New Lithium Battery Balancing Circuit Design Using Isolated Converter

Abstract

In order to pursue small size, high efficiency and low cost, this paper proposes a method of balancing the battery pack using an isolated bidirectional converter. The proposed converter adopts active clamping technology and synchronous rectification technology, combined with switch control, and can achieve zero voltage switching (ZVS) effect and improve efficiency. In order to improve the accuracy of the state of charge (SOC) estimation, the average SOC is calculated by a lookup table method and a Coulomb integration method to determine the equilibrium state of the battery pack.