Experimental and modeling analysis of thermal runaway for LiNi _{0 . 5} Mn _{0 . 3} Co _{0 . 2} O

Abstract

Summary The nickel‐rich lithium‐ion batteries (LIBs) are widely used as the energy source of new energy vehicles. But the relatively poor safety performance results in serious accidents, which attracts more and more attention of researchers. In this study, the thermal runaway (TR) features of a pouch cell consisted of LiNi0.5Mn0.3Co0.2O2/graphite are investigated by an extended volume‐accelerating rate calorimeter combined with resistance monitoring, voltage monitoring, and video imaging technologies. Based on these techniques, the TR process is divided into five representative stages, that is, the start of self‐heating, the venting of flammable gas, the volatilization of electrolyte, the melt of separator, and the internal short circuit of LIBs. Besides, a lumped‐parameter thermal model with high precision is developed to predict and explain the TR process. The heat generated by the decomposition of solid electrolyte interface (SEI), the reaction of anode‐electrolyte, the multiple phase transition of the cathode is considered as the main heating source of TR. The resistance shows a higher sensitivity to the SEI decomposition than temperature does. The venting process along with the evaporation of electrolytes provides significant opportunities to obstruct the TR. The interval time between voltage drop and temperature rise is 6.9 seconds, which is beneficial for the early warning of TR.

Study on the Thermal Runaway of a Sport Camera Lithium-Ion Battery Associated with Instrumental Analysis of Its Components

“…2), respectively, and the (d T /d t ) max was 84.98 °C min –1 . Self-heat rate is the most essential data needed for evaluating runaway hazards of LIBs under thermal failure . The (d T /d t ) max did not exceed 100 °C min –1 for both sets of experiments when the SOC of the battery was 25%, so T cr was not monitored.…”

“…Self-heat rate is the most essential data needed for evaluating runaway hazards of LIBs under thermal failure. 33 The (dT/ dt) max did not exceed 100 °C min −1 for both sets of experiments when the SOC of the battery was 25%, so T cr was not monitored. Compared to SOC = 0%, T onset was lower and both T max and (dT/dt) max reached were higher when the battery SOC was 25%.…”

Experimental and Modeling Analysis of Thermal Runaway for LiNi0.5Mn0.3Co0.2O2/Graphite Pouch Cell Triggered by Surface Heating

“…The highest temperature recorded at this moment was at No. The experimental data and phenomena showed that the TR triggered by the surface heat source of the battery is similar to the adiabatic TR process [13]. As the temperature increases, the decomposition of the SEI on the negative electrode surface occurs, and a large amount of flammable and explosive gas is generated by the reaction between the negative electrode and the electrolyte, causing an increase in the internal pressure of the battery [14].…”

“…The cell depressurizes in a relatively mild and stable manner. As the temperature continues to rise, the electrolyte will evaporate and overflow through the breach [13]. During the test, the erupting flammable and explosive gases served as the fuel, the oxygen provided by the external environment served as the oxidizer, and the splashing sparks served as the ignition source.…”

“…In recent years, numerous scholars have Energies 2024, 17, 826 2 of 16 investigated the TR properties of LIBs through experimental and modeling approaches. Tang et al [13] categorized the TR of the battery into five main stages based on characteristic temperatures observed during the TR process: start of self-heating, venting of flammable gases, volatilization of electrolyte, melt of separator, and massive ISC. They also developed a TR model incorporating five side reactions (SEI decomposition, anode-electrolyte reaction, separator melt, cathode decomposition, and electrolyte decomposition) to predict the TR behavior of the battery.…”