摘要
为实现退役动力电池的梯次利用,以软包磷酸铁锂电池为研究对象展开了电池容量与循环的特性研究,通过实验分析电池老化的机理及其老化的本质原因,认为活性锂离子损失、电极活性物质损失和电池内部极化反应是电池老化的根本原因。将电池循环老化过程分为循环初期、中期和后期3个阶段,发现循环初期电池容量衰减速率较快,中期衰减速率最慢,后期急速衰减。实验发现电池温度与倍率电流呈正比关系。且不同老化程度的电池在2C倍率放电状态下与温度存在正相关规律,即随着老化程度的加深,电池内部副反应热、极化热等情况增多,电池放电时温度不断上升,且温度变化率加快,健康状态最低的电池温度变化率最高达0.127℃/s。
In order to realize the echelon utilization of retired power batteries,the capacity and cycle characteristics of soft packed lithium iron phosphate battery were studied.The mechanism of battery aging and the essential reasons for aging were analyzed through experiments.The loss of active lithium ions,loss of electrode active substances and internal polarization reaction of the battery was believed to be the fundamental reasons for battery aging.The cycling aging process of batteries was divided into three stages:early,middle,and late stages.It is found that the capacity aging rate of batteries is faster in the early stage of cycling,the slowest in the middle stage,and rapid in the later stage.The experiment shows that the temperature of the battery is directly proportional to the rate current.Moreover,batteries with different degrees of aging exhibit a positive correlation with temperature under a 2C rate discharge state.As the aging degree deepens,the internal side reaction heat and polarization heat of the battery increase.The temperature of the battery during discharge continues to rise,and the temperature change rate accelerates.The temperature change rate of the battery with the lowest health state is as high as 0.127℃/s.
作者
王哲
周书民
汪志成
Wang Zhe;Zhou Shumin;Wang Zhicheng(East China University of Technology,Nanchang 330013,China;Jiangxi Engineering Research Center of New Energy Technology and Equipment,Nanchang 330032,China)
出处
《机电工程技术》
2023年第5期12-18,共7页
Mechanical & Electrical Engineering Technology
基金
江西省科技合作专项重点项目(20212BDH80008)
国家自然科学基金项目(12165001)
科技部常规性科技援外项目(KY201702002)
江西省重点研发计划项目(20181BBE58006)。
关键词
磷酸铁锂电池
梯次利用
老化特性
温度特性
lithium-ion phosphate battery
echelon utilization
aging characteristics
temperature characteristics
