塑料膜复合集流体在锂离子电池应用中的挑战与改进措施  

Challenges and improvement measures of plastic film composite current collectors for lithium-ion batteries

作　　者：董先锋 张稚国 李华清 王莉[1] 何向明[1] DONG Xianfeng;ZHANG Zhiguo;LI Huaqing;WANG Li;HE Xiangming(Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China;Jiangsu HanYe New Material Institute Co.,Ltd,Suzhou 215234,Jiangsu,China)

机构地区：[1]清华大学核能与新能源技术研究院,北京100084 [2]江苏瀚叶铜铝箔新材料研究院有限公司,江苏苏州215234

出　　处：《储能科学与技术》2024年第10期3388-3399,共12页Energy Storage Science and Technology

基　　金：自然科学基金(22279070,U21A20170);科技部重点研发计划(2019YFA0705703);中国博士后科学基金面上项目(2023M731917)。

摘　　要：塑料膜复合集流体(PFCC)是一种具有金属层+塑料聚合物+金属层的类三明治结构的新型电池集流体,可以提高锂离子电池的能量密度和安全性,因此受到了电池相关研究者的广泛关注。但PFCC也为锂离子电池的应用带来很多挑战,使其产业化进程缓慢。本文总结了其带来的诸多挑战,例如,聚合物-金属间结合力弱导致在聚合物层电解液浸泡时易脱层、导电性差使其过流能力下降、聚合物层易被腐蚀等,同时对其相关机理展开了详细的阐述:部分聚合物为非极性分子,与金属层间作用力弱;聚合物自身绝缘;PET易被催化解聚及热稳定性差等缺点。针对以上不足,本文系统地归纳了PFCC在锂离子电池应用技术中的发展历程,同时明确了可以通过界面工程、材料调控、加工技术和设备优化等方法、措施对其进行改进,例如:设置焊接质量的实时监控系统,建立多功能界面强化层,设计集流体内外功能性结构等,以期为PFCC的发展奠定理论基础,并推动PFCC在锂离子电池中的应用。A plastic film composite current collector(PFCC)is a new battery collector with a sandwich-like structure made of a two metal layer,plastic polymer,and another metal layer.IPFCCs have attracted research attention because they can improve the energy density and safety of lithium-ion batteries(LIBs).However,PFCCs have several disadvantages in the application of LIBs,which limits their industrialization process.This paper summarizes the their disadvantages,including weak polymer-metal adhesion,poor electrical conductivity,and poor corrosion resistance,Furthermore,the study discusses the related mechanisms of their disadvantages,including the weak physical and chemical forces of the interface bonding between polymer and metal layers;shortcomings of the polymers,such as their own insulating properties,the vulnerability of PET to catalytic depolymerization,and poor thermal stability;and the poor bonding force at the polymer-metal interface during electrolyte immersion and cold press processing.This paper systematically summarizes the development history of PFCCs in the LIB application technology,and simultaneously explains how they can be improved through interface engineering,material regulation,processing technology and equipment optimization,and other methods and measures,such as setting up a real-time welding-quality monitoring system,establishing a multifunctional interfacial reinforcement layer,and designing a functional structure inside and outside of the collector to lay the theoretical foundation for PFCC development and to promote the development of PFCCs in LIBs.

关 键 词：锂离子电池 复合集流体 金属涂层 塑料基膜 界面问题 

分 类 号：O69[理学—化学]