具备冗余单元的电池组放电效率研究

Research on discharge efficiency of battery pack with redundant cells

为了克服锂离子电池不一致性带来的成组电池放电效率低、使用寿命短、电池组安全性能差等问题,提出了一种具备冗余单元的高效的电池管理系统(battery management system,BMS)策略,即协同均衡电池管理法。根据该原理利用VB开发了一款仿真软件,利用该软件从冗余数量、切换时间/能量差、电池初始容量标准差等三个角度,以数值仿真的方法详细地分析了该策略对电池组放电效率的影响。通过实验对仿真数据进行了验证,结果表明,该策略可使成组电池的有效容量逼近单体电池的容量和,提高电池组的放电效率,并能在一定程度上延长电池组的使用寿命和增强电池组安全性能。

The inconsistency of the lithium battery brings these problems for the battery packs:low discharge efficiency,short lifespan and poor safety.This paper proposes a battery management system(BMS)strategy,which is highly efficient with the redundant units.In this paper,a simulation software is developed using Visual Basic.The software analyzed the impact of strategy on discharge efficiency of battery packs,using the numerical simulation from the angle of switching time,redundant amounts and the standard deviation of the battery and initial capacity.To verify the simulation data,this paper set up a battery pack with a cooperative and balanced BMS.Results of the simulation and experiment indicate that the BMS is high-efficiency and it can increase the discharge efficiency and make effective capacity of battery pack approach to the sum of battery cells.Also,the cooperative and balanced BMS can extend the life time of battery pack and enhance the security of battery pack.