Silane coupling agent treated copper foil as a current collector for silicon anode  

硅烷偶联剂处理铜箔用作高性能硅负极铜集流体

作　　者：MENG Xiang-juan ZENG Xiao-min JIANG Wei LI Si-yuan DU Qiao-kun JI Ze-kai ZHU Wei-wei LIU Chuang LIANG Cheng-du LING Min YAN Li-jing 孟祥娟;曾小敏;蒋伟;李嗣源;杜乔昆;季泽楷;朱伟伟;刘创;梁成都;凌敏;严立京(College of Chemical and Biological Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]College of Chemical and Biological Engineering,Zhejiang University,Hangzhou 310027,China

出　　处：《Journal of Central South University》2022年第11期3620-3629,共10页中南大学学报（英文版）

基　　金：Project(2019R01006)supported by the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang Province,China;Project(2018YFB0104300)supported by the National Key R&D Program of China。

摘　　要：Since the volume variation of silicon particles during cycling,the binding spots between Cu current collector and silicon anode raised to be one of the critical binding problems.In this work,an amino-modified Cu current collector(Cu^(*))is fabricated to tackle this issue.The amino groups on Cu^(*)surface increase its hydrophilicity,which is conducive to the curing process of aqueous slurry on its surface.Meanwhile,these amino groups can form abundant amide bonds with carboxyl groups from the adopted polyacrylic acid(PAA)binder.The combined action composed of the covalent bond and mechanical interlocking could reduce the contact loss inside the electrode.However,high concentration silane coupling agent treatment will weaken the surface roughness of Cu^(*)and weaken mechanical interlocking.What is more,the insulation of silane coupling agent reduces the conductivity of Cu and increases the impedance of battery.Considering the effect of silane coupling agent comprehensively,electrochemical performance of Cu^(*)-0.05%is best.采用了一种简单的铜集流体表面改性方法,成功在硅负极和集流体之间引入化学键作用力,以缓解硅在循环过程由于体积变化过大从集流体上脱出的问题。DAMO的涂覆使Cu^(*)表面负载氨基官能团。氨基官能团增加铜箔表面的亲水性,有利于以水作为溶剂的浆料在铜箔表面的固化过程。同时,氨基可以和黏结剂中羧基形成酰胺键,在铜集流体和硅负极之间构建化学键作用力。但高浓度的DAMO改变了铜箔表面形貌,降低了表面粗糙度,只能提供单纯的化学键作用力。同时,DAMO的绝缘性也降低了铜箔的导电性,增加了电池的阻抗。综合以上考虑DAMO膜的作用,当DAMO的浓度为0.05 wt%时,Cu^(*)表面既能保留机械互锁力,又可以提供化学键作用力,电极中集流体和活性层界面黏结强度增加,Si-Cu^(*)−0.05%的倍率性能和循环性能明显增强,循环100次之后,容量保持率为60%,比采用裸铜的硅电极电化学性能提升25%。

关 键 词：lithium ion batteries silicon anodes Cu foils surface modification 

分 类 号：TM912[电气工程—电力电子与电力传动]