Research on equalization control of lithium-ion battery pack based on SOC

Due to the differences in the manufacturing process and assembly methods of lithium-ion batteries for electric vehicles, it is very easy to produce the problem of power inconsistency after forming a group, so it is necessary to control the equalization of lithium-ion battery packs. In this paper, based on the analysis and comparison of various equalization topologies, an active equalization topology based on flyback transformer is proposed, and the SOC (state of charge) of lithium-ion battery is used as the equalization variable to formulate the corresponding equalization strategy. Finally, the effectiveness of the equalization scheme is verified under simulation conditions under three different operating conditions of lithium-ion battery charging, discharging and shelving, which proves that the equalization scheme has high efficiency and can effectively improve the inconsistency problem of lithium-ion battery packs.