荷电状态和电池排列对锂离子电池热失控传播的影响

Effects of state of charge and battery layout on thermal runaway propagation in lithium-ion batteries

当前锂离子电池热失控传播特性研究主要聚焦于电池形态和触发方式,本研究采用自行研制的锂电池阵列级联热失控实验平台,对不同荷电状态(state of charge,SOC)及不同排列间隔的锂离子电池热失控传播特性开展研究。结果表明:热失控传播速度随着SOC的增加而加快,100%SOC电池组中热失控传播结束时间比70%SOC电池组热失控传播结束时间少70 s,100%SOC电池组热失控最高温度可达621.81℃,50%SOC的电池不会出现热失控传播现象;对于100%SOC的电池,电池间横向间距越大,热失控越难在电池组之间传播,当电池间横向间距为3 mm时,热失控不会在电池组中传播。电池间的热失控主要以层传层的形式传播。本研究对优化电池布置、防止和控制电池热失控传播具有较高的应用价值。

Currently,studies on the thermal runaway propagation characteristics of lithium-ion batteries mainly focus on the battery shape and trigger mode.This study uses a selfdeveloped lithium-ion battery array cascade thermal-runaway experimental platform to investigate the thermal runaway propagation characteristics of lithium-ion batteries using different states of charge(SOC)and arrangement intervals.The results show that the rate of thermal runaway propagation decreases with a decrease in SOC.The total duration of thermal runaway propagation in a 70%SOC battery pack is 70 seconds longer than that in a 100%SOC battery pack.The maximum thermal runaway propagation temperature in a 100%SOC battery pack can reach 621.81℃,and no thermal runaway propagation occurs in a 50%SOC battery pack.For batteries with 100%SOC,the larger the transverse spacing between batteries,the more difficult it is for a thermal runaway to spread between battery packs.Thermal runaway will not spread in battery packs when the transverse spacing between batteries is 3 mm.The thermal runaway between batteries mainly propagates in a layer-by-layer approach.The research has a high application value for optimizing battery layout and preventing and controlling battery thermal runaway propagation.