摘要
为解决低采样频率下S_(OH)(电池健康状态)评估不准确的问题,提出一种基于PDF(概率密度函数法)的区域频率法。采用不同倍率下三元锂电池的充放电电压数据进行分析,采样频率为1/60 Hz,分别提取PDF峰高和区域频率作为健康因子,并建立与S_(OH)的关系。结果表明:随着电池充放电电流倍率的增加,PDF峰高作为健康因子与S_(OH)的拟合度降低,尤其在放电阶段,1C倍率下拟合度R^(2)仅为0.0971。当区域频率作为健康因子时,电池在不同倍率下充放电阶段S_(OH)模型的拟合度R^(2)均在0.95以上。当区域电压从100 mV增加到400 mV,模型的拟合度可达0.98以上。最后,使用1/2C倍率下电池老化数据对该方法进行验证,S_(OH)评估误差在2%以内,结果表明该方法可提高低采样频率下的电池S_(OH)评估的准确性。
A probability density function(PDF) based area frequency method was proposed to solve the problem of inaccurate battery health state S_(OH) assessment at low sampling frequency.The charging and discharging voltage data of ternary lithium batteries at different multiplicities were used for analysis with a sampling frequency of 1/60 Hz,and the PDF peak height and area frequency were extracted as health factors,respectively,and the relationship with S_(OH) was established.The results show that the fit of PDF peak height as a health factor with S_(OH) decreases as the charge/discharge current multiplier increases,especially in the discharge phase,the fit R^(2) is only 0.097 1 at 1C.When the regional frequency is used as the health factor,the R^(2) of the fit of the S_(OH) model is above 0.95 at different multipliers of the charge/discharge phase.When the regional voltage increases from 100 mV to 400 mV,the fit of the model is above 0.98.Finally,the method is validated using battery aging data at 1/2C magnification,and the S_(OH) evaluation error is within 2%,which shows that the method could improve the accuracy of S_(OH) evaluation of batteries at low sampling frequency.
作者
张子夏
廖强强
刘伟
蔡永翔
付在国
张雅
林志成
ZHANG Zixia;LIAO Qiangqiang;LIU Wei;CAI Yongxiang;FU Zaiguo;ZHANG Ya;LIN Zhicheng(Shanghai Engineering Research Center of Heat-Exchange System and Energy Saving,Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power,Shanghai University of Electric Power,Shanghai 200090,China;Electric Science Research Institute,Guizhou Power Grid Co.,Ltd.,Guiyang 550002,Guizhou Province,China)
出处
《化学工程》
CSCD
北大核心
2024年第1期18-23,共6页
Chemical Engineering(China)
基金
贵州省科技支撑计划(黔科合支撑[2022]一般012、一般015)。
关键词
三元锂离子电池
区域频率
概率密度函数
电池健康状态评估
采样频率
充放电电流倍率
ternary lithium-ion battery
regional frequency
probability density function
battery assessment of state of health
sampling frequency
charge/discharge current rate
