A modular nondissipative current diverter for EV battery charge equalization

This paper presents a new technique for equalizing a series battery stack using a modular nondissipative current diverter. The proposed scheme maintains each pair of battery modules at the same charge level by diverting the excess energy from the overcharged module to the weak one in a nondissipative manner. The equalizers are staggered to ensure balancing for the whole stack. Unlike previous schemes, which are based on a multi-winding transformer structure, the new scheme can be easily integrated with a series battery stack due to its modular nature where each equalizer is connected to a pair of modules.