摘要
动力电池中,大容量三元锂离子电池产量大、热失控危险性高,使用细水雾抑制其热失控火灾的研究受到广泛关注。本文以150 Ah大容量三元锂离子电池为研究对象,使用10 MPa细水雾分别采取连续释放策略和脉冲释放策略进行热失控火灾抑制实验,对比分析不同释放时间、脉冲周期、占空系数等参数对热失控行为、温度及产热速率等实验结果的影响,结果表明:相比普通容量的锂离子电池,大容量三元锂离子电池的热失控过程会反复发生多次更为剧烈的燃烧行为,温升速率增幅明显,但细水雾对其仍有较好的火灾抑制效果,且释放时间越长,灭火效果与冷却效果越好,但连续释放策略仍存在复燃现象,且随着释放时间的增加,冷却效率的增幅逐渐趋缓。针对大容量三元锂离子电池,脉冲释放策略的热失控火灾抑制能力优于连续释放策略,其能够快速扑灭明火且不发生复燃,有效降低了产热速率和电池表面最高温度。在本文条件下,耗水量为10 L、周期为10 s的脉冲细水雾,在占空系数为0.3时存在冷却效果的实验最优值,此时的脉冲释放与相同耗水量下的连续释放相比,产热速率下降了28%,电池表面最高温度下降了176℃。本文可为大容量三元动力电池系统的灭火设施设计提供参考。
Among power batteries,large-capacity NCM lithium-ion batteries have a large output and a high risk of thermal runaway.The research on using water mist to suppress thermal runaway fire has attracted wide attention.Herein,a 150 Ah large-capacity NCM lithium-ion battery is used with a 10-MPa water mist to adopt continuous and intermittent spray strategies for the thermal runaway fire suppression experiment.The influence of parameters on the thermal runaway behavior,such as different release times,a period of pulse,duty cycle,temperature,heat production rate,and other experimental results,were compared and analyzed.The results show that,compared with ordinary capacity batteries,the thermal runaway of large-capacity NCM lithium-ion batteries repeatedly occurs with intense combustion behavior,considerably increasing the temperature.However,water mist has an apparent fire suppression effect on the large-capacity NCM lithium-ion batteries.The longer the release time,the better the fire suppression and cooling effect.However,the continuous spray strategy still has a reignition phenomenon,and with the increase in release time,the increase of cooling efficiency gradually slows down.For large-capacity NCM lithium-ion batteries,the thermal runaway fire suppression ability of the intermittent spray strategy is better than that of the continuous spray strategy,which can quickly extinguish open flame without reignition and effectively reduce the heat production rate and the maximum temperature of the battery surface.Under the studied conditions,when the duty cycle is 0.3,the optimal cooling effect for the pulse water mist is at a water consumption of 10 L in a period of 10 s.Compared with the continuous spray under the same water consumption,the heat generation rate decreased by 28%,and the maximum temperature of the battery surface dropped by 176℃.This study can provide a reference for the design of fire-extinguishing facilities of large-capacity NCM power battery systems.
作者
韩路豪
王子阳
何骁龙
何春汕
石晓龙
姚斌
HAN Luhao;WANG Ziyang;HE Xiaolong;HE Chunshan;SHI Xiaolong;YAO Bin(State Key Laboratory of Fire Science,University of Science and Technology of China,Hefei 230026,Anhui,China)
出处
《储能科学与技术》
CAS
CSCD
北大核心
2023年第5期1664-1674,共11页
Energy Storage Science and Technology
基金
中央高校基本科研业务费专项资金资助(SA2320000012)。
关键词
三元锂离子电池
热失控
细水雾
连续释放
脉冲释放
NCM lithium-ion battery
thermal runaway
water mist
continuous spray
intermittent spray
