Experimental Study on Effects of Triggering Modes on Thermal Runaway Characteristics of Lithium-Ion Battery

Abstract

As an important component of new energy vehicles, the safety of lithium-ion batteries has attracted extensive attention. To reveal the mechanism and characteristics of ternary lithium-ion batteries under different trigger modes, an experimental system was established. The effects of different trigger modes on battery surface temperature, battery internal temperature, injection time, and battery voltage were analyzed. Among them, acupuncture, overheating, and overcharging are used as trigger conditions for mechanical, thermal, and electrical abuse. The results show that the injection time and surface peak temperature are positively correlated with the energy input before thermal runaway. Before the cell triggers abuse, the more input energy, the higher the cell surface temperature, the more serious the thermal runaway, and the higher the damage to the surrounding battery system. Under the same conditions, the intensity and damage degree of overcharge thermal runaway are greater than those of internal short circuit and overtemperature. The abnormal change of voltage suddenly rising and rapidly falling can be used as a condition to judge whether overcharge thermal runaway occurs. Finally, according to the temperature curves at different positions, the thermal diffusion law under different abuse conditions is summarized, which provides a basis for the safety design of the battery module.