摘要
锂离子电池的不一致性导致电池组的容量和寿命等指标显著小于电池单体,且该问题在梯次利用的应用场景下更为严重。电池组老化后,电池组内电池不一致性参数之间并非相互独立,而是相互耦合,因此造成电池组一致性建模困难,降低了电池组的能量利用率的估计精度。针对梯次利用电池筛选成组和成组后的状态评估,该文提出一种基于Copula理论的电池组一致性建模方法,同时实现了电池参数分布特性和参数间相关性的准确刻画。基于电池组一致性模型,提出一种电池组能量利用率估计方法,并进行实验验证,估计误差在1%以内。最后分析电池组能量利用率的影响因素,以指导电池组的优化成组和使用。
The inconsistency of lithium-ion battery cells has caused the lifetime and capacity of the battery pack to be much smaller than that of the battery cells,and this problem is more serious in the second-use applications.Along with the aging of the battery pack,the battery consistency parameters are mutual dependent,which causes battery pack consistency modeling difficult and state of health estimation inaccurate.Aiming at the grouping and the state evaluation stages of second-use batteries,this paper proposes a Copula-based battery pack consistency modeling method.The proposed method can describe the statistical characteristics of the battery consistency parameters and the dependence structure between parameters.Based on the consistency model,a battery pack energy utilization efficiency(EUE)estimation method is put forward and verified by experiments.The estimation error is within 1%.Finally,the influencing factors of EUE is analyzed to guide the optimal grouping and operation of second-use lithium-ion battery packs.
作者
赵伟
闵婕
李章溢
孙瑞
姜研
Zhao Wei;Min Jie;Li Zhangyi;Sun Rui;Jiang Yan(Electric Power Research Institute of Guangdong Power Grid Co.Ltd,Guangzhou 510080,China;Sunwoda Energy Solution Co.Ltd,Shenzhen 518000,China;Sunwoda Electronic Co.Ltd,Shenzhen 518108,China;School of Electric Power South China University of Technology,Guangzhou 510641,China;National Active Distribution Network Technology Research Center Beijing Jiaotong University,Beijing 100044,China)
出处
《电工技术学报》
EI
CSCD
北大核心
2021年第10期2190-2198,共9页
Transactions of China Electrotechnical Society
基金
国家重点研发计划资助项目(2018YFB0905304)。
关键词
锂离子电池组
梯次利用
一致性
能量利用率
Lithium-ion battery pack
second use
consistency
energy utilization efficiency
