摘要
放电容量损失是当前制约锂离子电池在低温环境下应用的主要瓶颈问题.预热是解决锂离子电池低温应用的关键方法.目前锂离子电池低温预热方法主要关注在预热速率、温度等方面,而忽略了锂离子电池预热后的可用能量.基于外部加热形式,理论分析了预热与锂离子电池可用能量之间的关系,实验研究了不同预热策略下锂离子电池的低温放电性能,提出了面向最大可用能量的锂离子电池低温预热能量管理方法.研究表明,预热时间与电池可用能量之间存在非线性关系.在0.5 C放电时,预热1分钟电池的可用能量比预热3分钟和5分钟高3.72％和5.95％.在1.0 C、1.5 C和2.0 C放电时,预热3分钟时电池性能表现最佳,此时仅消耗标称容量的4.13％,放电容量分别达到了额定容量的89.99％、75.17％、73.76％;相比预热1分钟和5分钟的电池,可用能量分别高0.16％、2.27％、6.80％和9.45％、12.26％、13.98％.低温预热时间应根据电池放电倍率调整,以实现电池可用能量的最大化.
Abstract
The loss of discharge capacity is currently the main bottleneck problem that restricts the application of lithium-ion batteries at low temperatures.Preheating is the key method to solve the low-temperature application of lithium-ion batteries.Currently,the low-temperature preheating methods for lithium-ion batteries mainly focus on the aspects of preheating rate and temperature,ignoring the available energy of lithium-ion batteries after preheating.This study theoretically analyzes the relationship between preheating and the available energy of lithium-ion batteries based on external heating method,experimentally studies the low-temperature discharge performance of lithium-ion batteries under different preheating strategies,and proposes a low-temperature preheating energy management method for lithium-ion batteries with maximum available energy.The research shows that there is a nonlinear relationship between preheating time and battery available energy.When discharged at 0.5 C,the battery with preheating for 1 minute has a higher available energy than that with preheating for 3 minutes and 5 minutes,which is 3.72％and 5.95％higher,respectively.When discharged at 1.0C,1.5 C,and 2.0 C,the battery performs best with preheating for 3 minutes,and only consumes 4.13％of the rated capacity.The discharge capacity can reach 89.99％,75.17％,and 73.76％of the rated capacity,respectively.Compared with batteries with preheating for 1 minute and 5 minutes,the available energy is 0.16％,2.27％,and 6.80％higher,respectively,and 9.45％,12.26％,and 13.98％higher,respectively.The low-temperature preheating time should be adjusted according to the battery discharge rate to maximize the available energy of the battery.
基金项目
广东省基础与应用基础研究基金资助项目(2022A1515110187)
广东省基础与应用基础研究基金资助项目(2022A1515110683)
广东省基础与应用基础研究基金资助项目(2022A1515140042)
国家科技期刊平台
NSTL
万方数据