Thermal Runaway Analysis of Ncm Ternary Lithium-Ion Batteries Under the Combined Effects of Humidity and Heat

Starting from the perspective of high-temperature heat abuse, this paper conducts experimental and simulation comparative analysis on the thermal runaway behavior of ternary lithium-ion batteries in high temperature and humidity environments. Nickel-cobalt-manganese ternary lithium-ion power batteries (NCM523) with 50% State of Charge (SOC) were selected as the research object. A constant power electric furnace of 1 kW was used as an external heat source. After 660 seconds of heating, the external heat source was removed to conduct the heat abuse experiment of NCM ternary lithium-ion batteries in humid and hot environments, and numerical simulation was carried out using COMSOL Multiphysics software. The results show that under normal humidity conditions, the increase in initial ambient temperature leads to an earlier occurrence of thermal runaway. For NCM ternary lithium-ion batteries with SOC of 50%, when the relative humidity is 50%, and the ambient temperature increases from 20°C to 40°C, the time for the battery to reach thermal runaway is shortened by 20.2%. At a room temperature of 30°C, when the ambient humidity increases from 50% to 100%, the peak temperature during the thermal runaway process increases by 37.2%. High temperature and high humidity environments significantly increase the risk of thermal runaway of NCM ternary lithium-ion batteries.