石墨负极界面SEI膜与锂离子电池热失控  

Solid electrolyte interphase (SEI) on graphite anode correlated with thermal runaway of lithium-ion batteries

作　　者：张佳怡 翁素婷 王兆翔[1,2,3] 王雪锋 ZHANG Jiayi;WENG Suting;WANG Zhaoxiang;WANG Xuefeng(Institute of Physics,Chinese Academy of Science,Beijing 110190,China;College of Materials Science and Opto-Electronic Technology,University of Chinese Academy of Sciences,Beijing 100049,China;School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;Tianmu Lake Institute of Advanced Energy Storage Technologies Co.,Ltd.,Liyang 213300,Jiangsu,China)

机构地区：[1]中国科学院物理研究所,北京110190 [2]中国科学院大学材料科学与光电技术学院,北京100049 [3]中国科学院大学物理科学学院,北京100049 [4]天目湖先进储能技术研究院有限公司,江苏溧阳213300

出　　处：《储能科学与技术》2023年第7期2105-2118,共14页Energy Storage Science and Technology

基　　金：国家自然科学基金项目(52172257,22005334);国家重点研发计划(2022YFB2502200);北京市自然科学基金(Z200013)。

摘　　要：随着商用锂离子电池(LIBs)的蓬勃发展,其安全性的欠缺成为日益凸显且亟待解决的问题。作为LIBs事故的重要形式之一,热失控过程与石墨负极固体电解质界面(SEI)膜密切相关。因此,深入了解和精准调控SEI膜的性质成为提高LIBs安全性的前提和重要途径。本文首先对SEI膜的组分、结构,以及形成原理进行了简要介绍,尤其强调了SEI膜在热失控过程中所起的关键作用。其次,探讨了热失控过程中与SEI膜相关的不安全因素及其机理。对SEI膜的分解、锂化石墨的热解、可燃气体的释放、锂沉积、正极过渡金属(TM)对SEI膜的影响几个过程的分析表明,需要同时提高SEI膜自身的热稳定性和Li+在其中的传输能力,才能有效提高电池的安全性能。依据材料的结构和成分、性质、性能之间的决定性关系,对SEI膜的改性进行了广泛研究。调控电解液组分或在负极电极内引入添加剂进而对SEI膜进行原位调控,以及构筑无机或有机组分的人工SEI膜均能够有效调控SEI膜的特性。最后,展望了未来SEI膜的相关研究和调控方向,为提高LIBs的安全性提供了理论依据和实验指导。With the rapid development of commercial lithium-ion batteries(LIBs),safety has become an increasingly prominent and urgent problem.As one of the important cases causing LIBs accidents,thermal runaway is closely related to the thermal stability of the solid electrolyte interface(SEI) on the graphite anode.Therefore,the properties of SEI must be deeply understood and accurately controlled to improve the safety of LIBs.Herein,the composition,structure,and formation principle of SEI are briefly introduced,and its key role in the processes of thermal runaway is emphasized.Second,the unsafe factors related to SEI and the mechanisms in the process of thermal runaway are discussed.We analyze the decomposition of SEI,the pyrolysis of lithiated graphite,the release of combustible gas,lithium plating,and the influence of transition metals on SEI.Our results indicate that the thermal stability and Li+ conductivity of SEI must be improved at the same time to effectively enhance the safety of LIBs.According to the decisive relationship between the structure and composition,properties,and properties of materials,researchers have conducted extensive research on the modification of SEI.The characteristics of SEI can be tuned by adjusting its electrolyte composition or introducing additives into the negative electrode to regulate the SEI in situ and constructing an artificial SEI with inorganic or organic components.Finally,we present the future research and regulation direction of SEI,which provides a theoretical basis and experimental guidance for improving the safety of LIBs.

关 键 词：锂离子电池 石墨负极 热失控 固体电解质界面膜 

分 类 号：TM911[电气工程—电力电子与电力传动]