Sharp object intrusion, particularly during automobile collisions, represents a significant risk to power batteries, potentially causing serious damage including ignition or explosion of lithium-ion batteries. This can lead to catastrophic outcomes for electric vehicles and pose risks to personal safety. This study aims to elucidate the safety performance of lithium-ion batteries under nail penetration conditions. Utilizing a custom-built experimental platform, we examined the effects of four parameters on battery safety: state of charge, penetration speed, penetration depth, and penetration location. Cylindrical 18650 lithium-ion batteries were subjected to penetration tests using a 5 mm diameter flat tungsten steel nail. The thermal runaway phenomenon was monitored using an infrared camera, and data such as temperature, open-circuit voltage, and load were recorded before and after the tests. Our findings indicate a clear pattern in the batteries' response to nail penetration; they do not immediately undergo thermal runaway but exhibit a delayed reaction. Factors such as higher states of charge and greater penetration depths significantly increase the likelihood of thermal runaway, which is also more severe when penetration occurs closer to the battery's positive and negative terminals. However, the speed of penetration does not have a significant correlation with the occurrence of thermal runaway. Based on these results, we offer recommendations for the transport, safe usage, and early warning algorithm design of lithium-ion battery packs.
维普
万方数据