Lithium-Ion Battery Thermal Runaway Electro-Thermal Triggering Method and Toxicity Analysis

Abstract

In high temperature condition, lithium-ion batteries have a greater risk of thermal runaway. Lithium-ion batteries may be exposed to smoke, combustion, or even explosion, which poses a greater threat to humans and the environment. In this paper, the electro-thermal triggering method is used to induce thermal runaway of the lithium-ion batteries. The most representative ternary polymer lithium-ion battery (NMC), lithium cobalt oxide battery (LCO), lithium iron phosphate battery (LFP) in the market were selected as experimental samples, all using 18650 batteries, and then the state of charge of battery samples were adjusted to 0%, 30%, 50%, 100%. The thermal runaway reaction phenomenon of lithium-ion batteries and the surface temperature of the batteries were recorded. The positive electrode samples of the batteries were characterized by X-ray diffraction and electron microscopy, and the thermal runaway reaction products were analyzed. The results show that with the increase of the state of charge, the thermal runaway reactions of the batteries are more severe. Thermal runaway reaction products contain a large amount of toxic substances, and prevention and protection are necessary.