细水雾抑制锂离子电池热失控及火焰对抗研究
Study on the suppression of thermal runaway and flame confrontation of lithium-ion batteries with water mist
张倩 1陈慧敏 1金渊 1刘通2
作者信息
- 1. 国网北京市电力公司电力科学研究院,北京 100075
- 2. 中国矿业大学 安全工程学院,江苏 徐州 221116;中国科学技术大学 火灾科学国家重点实验室,安徽 合肥 230026
- 折叠
摘要
细水雾凭借其冷却效果成为锂离子电池热失控防治的有效技术手段之一.本研究考虑安全阀喷出气体的热量损失,对比了不同热失控阶段应用细水雾抑制的效果,分析了热失控过程中各部分的热量,解释了热失控期间电池火焰和细水雾对抗的动力学原理,主要结论如下:细水雾冷却抑制热失控存在临界积累热密度,超过该临界值后,细水雾将无法抑制热失控的发展,但能够显著减少热失控后电池冷却所需的时间;在热失控触发后会出现细水雾和热失控火焰的对抗现象,其显著改变了火焰高度,使对抗界面的压力显著增加.本文提出的修正冷却倍率因子可有效判断细水雾与电池火焰对抗状态.
Abstract
The efficacy of fine water mist as a cooling medium has garnered acclaim for its superior performance in mitigating ther-mal runaway phenomena within lithium-ion batteries.This inves-tigation comprehensively evaluates the role of heat dissipation from safety valve-released gases and assesses the suppressive ef-fects of fine water mist on the progression of thermal runaway at various stages.The study meticulously analyzes the thermal dy-namics throughout the thermal runaway event,elucidating the ki-netic principles that underpin the interaction between the battery flame and the fine water mist.The salient findings from this re-search are as follows:A critical threshold of accumulated heat den-sity is identified,beyond which the fine water mist's cooling effect fails to inhibit thermal runaway,although it substantially dimin-ishes the cooling duration post-thermal runaway;The initiation of thermal runaway is accompanied by a dynamic interaction with the fine water mist,which is observed to alter the flame's morphology and to increase the interfacial pressure significantly.This research introduces a novel cooling efficacy factor that quantifies the equi-librium state between the fine water mist and the thermal runaway flame,providing a nuanced assessment of the cooling strategy's effectiveness.
关键词
锂离子电池/细水雾/热失控/积累热密度/冷却Key words
lithium-ion batteries/fine water mist/thermal run-away/accumulated heat density/cooling引用本文复制引用
基金项目
国家电网公司总部科技项目(5400-202355235A-1-1-ZN)
出版年
2024
NETL
NSTL
万方数据