摘要
由于不一致性问题和短板效应的存在,动力锂离子电池串并联成组后性能会比单体进一步降低。以新电池筛选以及旧电池梯次利用为背景,选取电学模型分析了储能系统用大容量锰酸锂电池和磷酸铁锂电池的模型状态参数,并通过等效电路的微分方程建立了单体电池和串并联电池组的计算机仿真模型。为验证仿真模型精度以及分析串并联仿真结果,分别对不同内阻分布、荷电状态分布和单体容量分布的筛选结果进行倍率充放电实验,研究了单体电池参数不一致程度和串并联连接方式对电流不平衡度的影响。本文提出的串并联仿真方法为评估动力电池组和储能系统的性能提供了重要手段。
Due to performance inconsistency and buckets effect,the performance of series-parallel-connected power lithium ion battery pack is not so good as that of single power lithium ion battery.Taking the screening of new power lithium ion batteries and re-usage of old power lithium ion batteries in echelon as the background of the research,electrical model of high-capacity LiMn2O4 battery and that of high-capacity LiFePO4 battery applied to energy storage system are built respectively and used to analyze state parameters of the models,and by means of differential equations of the equivalent circuits a simulation model for series-parallel-connected power lithium ion battery pack and that for single power lithium ion battery are established.To validate the accuracy of the established simulation models and analyze simulation results of series-parallel-connected power lithium ion battery pack,the charging/discharging experiments under different charging rate are made for results screened in accordance with single battery capacity distribution,state of charge（SOC） distribution and internal resistance distribution to research the inconsistency degree of single battery parameter and the influences of series-parallel connection modes on unbalanced degree of current.The proposed simulation method is available for reference to the assessment on performance of power battery peck and energy storage system.
出处
《电网技术》
EI
CSCD
北大核心
2012年第10期70-75,共6页
Power System Technology
基金
"十一五"国家科技支撑计划重大项目(2011BAA07B07)~~
关键词
串并联
模型参数
微分方程组
电流不平衡
series-parallel connection
model parameters
differential equations
unbalanced currents
