基于电化学阻抗谱的锂离子电池内部温度估算研究  

Estimation of Internal Temperature of Lithium-ion Battery Based on Electrochemical Impedance Spectroscopy

作　　者：宋明超 李国春[1] 王丽梅[1] 盘朝奉[1] Song Mingchao;Li Guochun;Wang Limei;Pan Chaofeng(Automotive Engineering Research Institute,Jiangsu University,Zhenjiang City,Jiangsu Province 212013,China)

机构地区：[1]江苏大学汽车工程研究院,江苏省镇江市212013

出　　处：《农业装备与车辆工程》2020年第5期56-61,共6页Agricultural Equipment & Vehicle Engineering

摘　　要：针对电动汽车用动力电池组中单体电池内部温度估算精度不高,容易造成热失控起火等安全问题,提出一种基于电化学阻抗谱特征量的锂离子电池内部温度在线估算方法。首先以不同SOH(State of Health,健康状态)及SOC(State of Charge,荷电状态)下三元锂离子单体电池作为研究对象,使用电化学工作站在不同环境温度下对其进行EIS(Electrochemical Impedance Spectroscopy,电化学阻抗谱)试验,在0.01~10 000 Hz的激振频率范围内分析相移值曲线的分布规律,结果表明:在10~800 Hz的特定频率区间内,相移值曲线不受电池SOC及SOH干扰,且相移绝对值与电池内部温度存在良好的映射关系,进而确定了温度与相移值之间的唯一函数关系表达式,得到了电动汽车用三元锂离子电池内部温度在线估算方法。An on-line temperature estimation method for lithium-ion batteries based on electrochemical impedance spectroscopy(EIS) characteristics was proposed to solve the safety problem caused by low accuracy of internal temperature estimation in single battery and easy to cause thermal runaway accidents.Firstly,NCM lithium-ion batteries with different SOH(State of Health) and SOC(State of Charge) were studied.EIS(Electrochemical Impedance Spectroscopy) tests were carried out at different ambient temperatures using electrochemical workstations.Phase shift curves were analyzed in the excitation frequency range of 0.01 Hz to 10 000 Hz.The results show that the phase shift curve was not disturbed by SOC and SOH in the specific frequency range of 10 Hz to 800 Hz,and the absolute value of phase shift had a good mapping relationship with the temperature inside the battery.Then the unique function expression between temperature and phase shift was determined,and the on-line temperature estimation method of ternary lithiumion batteries for electric vehicles was obtained,which was of great significance to the driving safety of electric vehicles.

关 键 词：锂离子电池 内部温度 电化学工作站 实时在线 

分 类 号：U469.72[机械工程—车辆工程]