磷酸铁锂极片导电网络的结构设计与性能研究  

Structural Design and Performance of Conductive Network of LiFePO_(4) Electrode

作　　者：于宝军 方聪聪 刘伯峥 董世佳 曾涛[1] YU Baojun;FANG Congcong;LIU Bozheng;DONG Shijia;ZENG Tao(Tianjin Lishen Battery Joint-Stock Co.,Ltd.,Tianjin 300384)

机构地区：[1]天津力神电池股份有限公司,天津300384

出　　处：《湖北理工学院学报》2024年第3期34-38,70,共6页Journal of Hubei Polytechnic University

基　　金：国家重点研发计划项目(项目编号:2022YFB2404802)。

摘　　要：炭黑(CB)、多壁碳纳米管(MWCNTs)、石墨烯(Gr)和单壁碳纳米管(SWCNTs)导电剂材料的结构和尺度具有明显区别。CB、MWCNTs和Gr在极片导电网络结构中负责构建短程导电网络结构,SWCNTs司职构建长程导电网络通路。文章依据导电剂材料特点设计磷酸铁锂正极片三维导电网络结构,对极片导电网络结构进行表征及确认。结果表明,Gr片径大于MWCNTs长度,相比CB、MWCNTs和SWCNTs复合,CB、Gr和SWCNTs复合构建的三维导电网络结构具有短程导电网络结构尺度优势,在性能上对电芯循环寿命无劣化,可降低直流内阻,提升4 C倍率充放电性能4%以上。The basic structure and scale of carbon black(CB),multi-walled carbon nanotubes(MWCNTs),graphene(Gr)and single-walled carbon nanotubes(SWCNTs)conductive materials are obviously different.CB,MWCNTs,and Gr are responsible for the construction of short-range conductive network structures in the conductive network structure of the pole piece,while SWCNTs are in charge of the construction of the long-range conductive network pathways.Based on the material characteristics of the conductive agent,the three-dimensional conductive network structure of the positive electrode of LiFePO_(4) was designed and the characterization and confirmation of the electrode conductive network structure were conducted.The results showed that the diameter of the graphene sheet was larger than the length of the multi-walled carbon tube,and compared with CB,MWCNTs and SWCNTs composite,the three-dimensional conductive network structure constructed by the composite of CB,Gr and SWCNTs was better in short-range scale conductive network structure,which had no degradation of the cycle life of the battery cell in terms of performance,reduced the DC internal resistance,and enhanced the 4 C multiplicity charging and discharging performance by more than 4%.

关 键 词：石墨烯 导电剂 三维导电网络 磷酸铁锂 

分 类 号：TM242[一般工业技术—材料科学与工程]