再利用退役锂动力电池的性能评估

Performance assessments of retired lithium-ion power batteries for reuse

以电动汽车退役锂电池为研究对象,采用外观检查、电池容量测试、脉冲特性曲线、电化学阻抗谱等多种方法评估电池外部及内部特性。研究结果表明:通过外观检查和容量测试将退役锂电池初步筛选和分组;脉冲放电电压是评判电池一致性的一个重要指标;从阻抗角度分析影响退役电池容量衰减因素,首先是浓差极化阻抗,其次是电荷转移电阻,而欧姆内阻的影响较小;退役电池的状态评估和一致性分组需要采用多种电池性能参数综合判断。

The external and internal characteristics of retired lithium ion batteries from electric vehicles were evaluated using observational check,battery capacity measurement,pulse characteristic curve and electrochemical impedance spectroscopy.The results show that the retired lithium ion batteries are preliminary screened and grouped by observational check and battery capacity measurement.The voltage of pulse discharge is an important index for the judgment of battery consistency.The influence factors of battery capacity fading in the light of electrochemical impedance spectroscopy include:the main one is the impedance of concentration polarization,and the secondary one is the charge transfer resistance.There is little effect of ohmic resistance on battery capacity fading.The condition assessments and consistency sectionalization of retired batteries need synthetic judgments by their different performance parameters.