退役锂电池梯次利用主动均衡方法研究

Research on active equalization method of retired lithium-ion batteries for the echelon utilization

针对退役锂电池数量多、不一致性严重等问题,提出基于Buck-Boost电路的分组双向主动均衡结构。以荷电状态(SOC)为均衡变量,电池小组内采用基于单电感的集中式均衡拓扑结构和均值-差值均衡算法,电池小组间采用分布式均衡拓扑结构和极差法及相邻差值法结合的均衡策略,分别实现电池小组内任意单体电池间均衡和相邻电池小组间均衡。12节退役电池的静置均衡和充电均衡实验结果表明,本文提出的均衡方法能快速有效地改善退役电池组的不一致性,均衡时间分别为98 min和87 min。

Aiming at the problems of large number and serious inconsistency of retired lithium batteries,a grouping bidirectional active equalization structure based on buck-boost circuit is proposed.SOC is used as the equalization variable.Centralized equalization topology based on single inductor and mean difference algorithm are adopted for balancing within the battery group,and distributed equalization topology and the equalization strategy range method combined with adjacent difference method are used for balancing between battery groups,balance respectively.The experimental results of static equalization and charge equalization of 12 retired batteries show that,the proposed equalization method can improve the inconsistency of retired batteries fast and effectively,and the equalization time is 98 min and 87 min respectively.