Abstract: The overall performance of the lithium-ion battery pack is greatly reduced by the problem of inconsistency. Equalization control is currently the only effective way of reducing the inconsistency of battery pack. This paper proposes an equalization control strategy, based on the equalization circuit of Buck-Boost, which the State Of Charge（SOC） of lithium-
ion battery as equalization object, after analyzing the mainstream equalization design. And it presents a SOC estimation algorithm based on dual-model adaptive extended Kalman filter. The experimental results show that this method can effectively ameliorate the inconsistency of battery pack, and improve the capacity utilization.

Key words: lithium-ion battery pack, inconsistency, balance, extended Kalman filter, state of charge estimation

摘要： 不一致性问题极大地降低了锂离子电池组的整体性能，均衡控制是目前能有效改善电池组间不一致性的唯一办法。在分析了目前主流均衡设计方案的基础上，针对Buck-Boost均衡电路，提出了以锂电池荷电状态（SOC）为均衡对象的均衡控制策略。同时，设计了一种新式的基于双模型自适应扩展卡尔曼滤器的SOC估算方法。实验结果表明，该均衡控制策略改善了电池组间的不一致性，提高了容量利用率。

关键词: 锂离子电池组, 不一致性, 均衡, 扩展卡尔曼滤波, SOC估算