Case Study of Repeatability, Different Speeds, and Different SOCs on Battery Squeeze Test

Abstract

This study aimed to achieve a clear understanding of the response characteristics of soft pack battery extrusion conditions under various situations. In this study, we chose a LiCoO2 battery as the research object of the extrusion experiment. First, the repeatability of the extrusion test on the battery was verified. A quasi-static extrusion test was conducted on three groups of batteries in the same state, and the load-displacement curves of the three groups of experimental batteries were almost the same. Then, the influence of the extrusion speed on the battery thermal runaway was studied. The results show that a different extrusion speed has a certain impact on the thermal runaway performance of the battery. The peak load of the battery is lower at a lower speed. Finally, the study found that every 20% change in SOC has a greater impact on the battery response under a squeeze. The larger the SOC, the more severe the battery thermal runaway. Through an analysis of multiple experimental cases, it is possible to have a deeper understanding of the temperature and voltage characteristics of lithium batteries when a thermal runaway occurs, which provides ideas for monitoring the trend of the thermal runaway of electric vehicles.

Safety Performance and Failure Criteria of Lithium-Ion Batteries under Mechanical Abuse

“…Batteries with high SOC exhibit a faster rate of temperature increase when subjected to mechanical abuse, and this is due to the fact that batteries with high SOC also generate higher currents after experiencing mechanical abuse, resulting in the release of larger amounts of heat [37]. Ren et al also pointed out in the literature [40] that for batteries with a low state of charge (SOC), the heat generated during the internal short circuit (ISC) is smaller and the chemical reactions inside the battery are still controllable. However, for batteries with high SOC, a large amount of heat is released due to ISC, causing the battery temperature to rapidly rise to the triggering temperature for SEI membrane decomposition and anode decomposition.…”

Multiparameter Comprehensive Thermal Runaway Warning Model of Lithium‐Ion Battery under Overcharge Condition

“…[2][3][4] Therefore, many scholars have researched methods to monitor and mitigate TR accidents in batteries. [5][6][7][8][9] Koch et al [10] used a multisensor system to detect TRs and identify TR phenomena quickly and reliably. Jin et al [11] developed a sensitive detection method based on H 2 gas capture that could detect trace amounts of Li dendrite formation, providing an effective method for early safety warning.…”