A Fast Active Cell Balancing Strategy for Lithium-ion Battery Packs

Development of reliable and efficient battery management systems (BMS) is determinant in the path of vehicles towards electrification. In this work, we speed up the cell balancing process of a Li-ion battery pack by introducing a novel state-of-charge (SOC) balancing strategy. The strategy takes advantage of the existing 12 volts battery in electric and hybrid vehicles as an auxiliary dc bus assisting with the SOC balancing process for the Li-ion battery pack. The proposed method is capable of conveying energy for up to five adjacent cells for SOC balancing. The simulation results on a string of 8 series cells confirm the effectiveness of the proposed strategy.