基于电化学阻抗谱的电池组不一致性诊断  

Diagnosis for Battery Module Inconsistencies Based on Electrochemical Impedance Spectroscopy

作　　者：姚晗欣 王学远[1,2] 袁永军[1,2,3] 戴海峰 魏学哲[1,2] Yao Hanxin;Wang Xueyuan;Yuan Yongjun;Dai Haifeng;Wei Xuezhe(School of Automotive Studies,Tongji University,Shanghai 201804;Clean Energy Automotive Engineering Center,Tongji University,Shanghai 201804;Shanghai Fire Cloud New Energy Technology Co.,Ltd.,Shanghai 201806)

机构地区：[1]同济大学汽车学院,上海201804 [2]同济大学新能源汽车工程中心,上海201804 [3]上海炙云新能源科技有限公司,上海201806

出　　处：《汽车工程》2024年第7期1167-1176,共10页Automotive Engineering

基　　金：国家自然科学基金(52207242);汽车安全与节能国家重点实验室开放基金(KFY2226)资助。

摘　　要：电池组中的单体电池之间可能会存在温度、荷电状态、老化状态(容量和内阻)等不一致。由于“短板效应”的存在,不一致性将会影响电池组的整体性能发挥,及时准确地进行不一致性诊断非常必要。考虑到上述提及的不一致性会对电极过程特性产生影响,进而反映在电化学阻抗谱(EIS)和弛豫时间分布(DRT)上,本文在结合等效电路厘清几种不一致性对EIS和DRT的影响规律后,创新性地提出了一种基于EIS和DRT的电池组不一致性诊断方法。通过将异常电池混入一组一致性良好的电池中,对比分析了K-means、AP和DBSCAN等无监督聚类算法性能,结果表明DBSCAN诊断准确率为99.2%,可以实现电池组内单体电池不一致性差异的准确诊断。There may be inconsistencies in temperature,charge state,aging state(capacity and internal resistance)between individual cells in a battery module.Due to the existence of the"short board effect",the incon-sistencies will affect the overall performance of the battery module,so timely and accurate inconsistencies diagnosis is very necessary.Considering that the above-mentioned inconsistencies will affect the electrode process characteris-tics,which will be reflected in the Electrochemical Impedance Spectroscopy(EIS)and Distribution of Relaxation Time(DRT),in this paper,after clarifying the effect of several kinds of inconsistencies on EIS and DRT by com-bining the equivalent circuits,an inconsistencies diagnosis method for battery modules based on EIS and DRT is in-novatively proposed.The performance of unsupervised clustering algorithms such as K-means,AP(Affinity Propa-gation)and DBSCAN(Density Based Spatial Clustering of Applications with Noise)is comparatively analyzed by mixing the abnormal batteries into a group of batteries with good consistency.The results show that the DBSCAN diagnostic accuracy is 99.2%,which can realize the accurate diagnosis of the inconsistency difference of single cells within the battery module.

关 键 词：锂离子电池 电化学阻抗谱 弛豫时间分布 不一致性 无监督聚类 

分 类 号：TM912[电气工程—电力电子与电力传动]