三元锂离子动力电池热失控及蔓延特性实验研究  

Experimental study on the thermal runaway and its propagation of a lithium-ion traction battery with NCM cathode under thermal abuse

作　　者：王淮斌 李阳 王钦正 杜志明[3] 冯旭宁 WANG Huai-bin;LI Yang;WANG Qin-zheng;DU Zhi-ming;FENG Xu-ning(China People’s Police University,Langfang 065000,China;State Key Laboratory of Automotive Safety and Energy,Tsinghua University,Beijing 100084,China;State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]中国人民警察大学,廊坊065000 [2]清华大学汽车安全与节能国家重点实验室,北京100084 [3]北京理工大学爆炸科学与技术国家重点实验室,北京100081

出　　处：《工程科学学报》2021年第5期663-675,共13页Chinese Journal of Engineering

基　　金：科技部国际合作资助项目(2019YFE0100200);国家自然科学基金资助项目(51706117,52076121);2019年度警察大学实验创新平台专项课题资助项目(2019sycxpd001)。

摘　　要：以电动汽车车用额定容量为42 A·h的三元方壳锂离子电池单体和模组为研究对象,研究其在加热条件下单体的绝热热失控特性及成组后侧向加热热失控蔓延特性.结果表明,锂离子电池在发生热失控时,内部最高温度可达920℃,电池表面和内部最大温差达403℃;热失控首先在迎向热流的面触发,随后蔓延至整个电池;满电状态下的锂离子电池内部热失控蔓延时间介于8~12 s;热失控蔓延过程中锂离子电池的温度特征与绝热热失控测试相比存在较大差异性;热失控喷发颗粒物中,LiF及石墨质量分数占80%以上;模组中失控电池产生的总能量中用于自身加热和喷发损失的占90%左右,热失控释放总能量的10%足以触发热失控蔓延.本文为研究三元锂离子电池模组安全设计、热失控蔓延抑制及新能源汽车的火灾事故调查提供了参考.Traction battery is the core component of the electric vehicle.To obtain longer driving ranges,conventional lithium-ion batteries with LiMn_(2)O_(4),LiCoO_(2),and LiFePO_(4) cathodes were gradually replaced by LiNi_(x)Co^(y)Mn_(1−x−y)O_(2)batteries.With the increasing energy density and chemical activity of the lithium-ion traction battery,its thermal stability gradually decreases and safety hazards become increasingly serious.In recent years,thermal runaway incidents with traction batteries have occurred frequently at home and abroad,seriously disturbing the development of electric vehicles.Solving the safety problems associated with thermal runaway(TR)and thermal runaway propagation(TRP)of the lithium-ion battery is urgent.In this paper,TR and its propagation behavior,associated with a 42 A·h prismatic lithium-ion battery with a LiNi^(1/3)Co^(1/3)Mn^(1/3)O_(2)cathode for electric vehicles,were studied under thermal abuse conditions on the cell and module levels.The results indicate that the maximum temperature approaches 920℃inside the cell.The maximum temperature difference is up to 403℃within the cell during TR,and the maximum temperature rise rate inside the cell is 40℃·s^(−1).The TRP time within a lithium-ion battery is 8–12 s under 100%state-of-charge(SOC),and the duration of the vent is 14–18 s.The temperature characteristics of the lithium-ion battery display large differences for the TRP test and adiabaticTR test.In a propagation test,the TR initiates from a forward surface toward the failure point,whereas under the adiabatic test the TR occurs simultaneously in the cell.More than 80%of the particles vented from the cell are LiF and graphite during the adiabatic test.Approximately 90%of the heat released by the TR is used for heating the residual and venting particles of the cell.The study offers a reference guide for the safety design and mitigation strategy of TRP in lithium-ion battery modules,and accident investigations of new energy vehicles.

关 键 词：锂离子电池 热失控 热失控蔓延 储能 安全性 

分 类 号：X913.4[环境科学与工程—安全科学] TM911.3[电气工程—电力电子与电力传动]