Abstract: Aiming at the inconsistency of voltage, capacity and internal resistance of lithium-ion batteries in the process of series-parallel connection, the traditional double-layer Buck-Boost equalization circuit module is improved to solve the problem that the traditional equalization circuit can not equalize the neighboring single batteries and the equalization rate is improved as well. On this basis, *87* a new lithium battery group layer equalization topology circuit is designed. The equalization strategy adopts fuzzy control and traditional mean value control algorithm respectively, and the state of charge （SOC） of each cell is taken as the equalization control target of the battery pack, and the improved Buck-Boost circuit is used within the battery pack and the bidirectional flyback circuit is used between the battery packs, and the model is constructed and analyzed by simulation in Matlab/Simulink. The comparative results show that the use of fuzzy control method shortens the equalization time by 13.8% compared with the traditional mean value control method, and can realize the SOC equalization between lithium battery cells faster, which verifies the feasibility of the proposed scheme.