湿热环境下NCM三元锂离子电池热失控分析

从高温热滥用角度出发，对高湿高温环境中三元锂离子电池的热失控行为进行实验和模拟的对比分析.选择荷电量(SOC)为50%的镍钴锰三元锂离子动力电池(NCM523)作为研究对象，利用恒定功率1kW 的电热炉作为外加热源，加热660s后撤掉外热源，进行湿热环境下NCM三元锂离子电池热滥用实验，并利用COMSOL多物理场仿真软件进行数值模拟.结果表明:常湿条件下，环境初始温度的提高，造成热失控发生的时刻显著提前.对于SOC为50%的NCM三元锂离子电池，在相对湿度为50%的条件下，当环境初始温度由20℃增加到40℃时，电池达到热失控的时间提前了20.2%；在室温为30℃条件下，当环境湿度由50%增加到100%时，热失控导致的最高温度增加了37.2%.高温高湿环境将造成NCM三元锂离子电池热失控的危险性显著增加.

Thermal Runaway Analysis of NCM Lithium-Ion Battery in Humid and Hot Environment

From the perspective of heat abuse， the thermal runaway behavior of the NCM ternary lithium-ion battery in hot and high humid environment were analyzed based on tests and simulations. The NCM523 nickel-cobalt-manganese lithium-ion power battery with 50% SOC was selected as the object of study. An electric furnace with a constant power of 1kW was used as an external heat source， after 660s of heating， the external heat source was removed， and the heat abuse experiment of NCM ternary lithium-ion battery in humid and hot environment was carried out. The simulation was conducted by COMSOL Multiphysics software. The results show that for NCM lithium-ion battery with normal relative humidity， the increase of the initial surrounding temperature can lead to an earlier occurrence of the thermal runaway. Under 50% relative humidity， when the ambient temperature increases from 20℃ to 40℃， the time for the battery to reach thermal runaway is shortened by 20.2%. At 30℃， when the ambient humidity increases from 50% to 100%， the peak temperature in the process of thermal runaway is increased by 37.2%. The hot and high relative humidity has a significant enhancement effect on the risk of the thermal runaway of the NCM lithium-ion battery.