충전상태에 따른 리튬이온배터리 화재에 관한 실험 및 모델링 연구

Abstract

Among the secondary batteries, lithium ion battery is most popular due to their advantages such as high energy density and the absence of heavy metals, and usage is expected to continue to increase. However, several accidents have occurred due to the safety issues of lithium-ion batteries and especially the risk of a fire explosion should be addressed. Therefore, in this study, a cone calorimeter experiment was performed according to the state of charge of the Li-ion battery for basic data for extinguishing when a fire occurred. Through the experiment, the more the battery was charged, the stronger the intensity of the explosion, and no explosion occurred when the battery was not charged. In addition, it was confirmed that the higher the state of charge, the higher the CO and CO2 emissions, and the higher the heat release rate. Next, a modeling study was performed using hydrocarbon-based fuels to increase the number of ions as the battery was charged. In the experiments conducted using methane and ionizer, the increase of CO emission when the fuel was ionized was confirmed in the same way as the cone calorimeter experiment, and the increase of NOX was also confirmed in the results through the gas analyzer. From the results using numerical analysis, it was also confirmed that when ionized, CO and NOX emissions increased. Through these results, it was confirmed that the risk of fire increases and the emission of harmful gases increases as the state of charge of the battery increases. Also, it is thought that the heat release rate results conducted through the study can be presented as basic data for the construction of fire extinguishing agents or fire extinguishing equipment.