无枝晶金属锂负极用钨青铜改性碳纤维膜集流体  

Lithium tungsten bronze modified carbon fiber membrane current collectors for dendrite-free metal lithium anodes

作　　者：肖岩 王宏刚 李线绒[1] 田柱 李雪渊 张玉平 尤东江 董才富 康利涛 姜付义[2] XIAO Yan;WANG HongGang;LI XianRong;TIAN Zhu;LI XueYuan;ZHANG YuPing;YOU DongJiang;DONG CaiFu;KANG LiTao;JIANG FuYi(College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;School of Environmental and Material Engineering,Yantai University,Yantai 264005,China;Weichai Power Co.,Ltd.,Weifang 261001,China)

机构地区：[1]太原理工大学材料科学与工程学院,太原030024 [2]烟台大学环境与材料工程学院,烟台264005 [3]潍柴动力股份有限公司,潍坊261001

出　　处：《中国科学：技术科学》2020年第5期562-570,共9页Scientia Sinica(Technologica)

基　　金：国家自然科学基金(批准号:51502194,21606191,51772257);山东省重大基础研究计划(编号:ZR2018ZC1459)资助项目。

摘　　要：采用静电纺丝法首先制备了聚丙烯腈-锂钨青铜(PAN-Li0.47WO2.89)复合纤维膜,后经预氧化、碳化处理获得锂钨青铜改性的碳纤维膜复合集流体(C(PAN)-Li0.47WO2.89).作为金属锂负极集流体,该复合纤维膜具有导电率高、比表面积大(52.84m^2g^-1)等优点,可以有效降低集流体表面的锂沉积电流密度与锂沉积量;与此同时,在复合纤维中引入的高亲锂性Li0.47WO2.89可以有效降低锂沉积成核过电势、增加晶核密度,改善锂沉积-剥离反应的可逆性与均匀性.在0.5 mA cm^-2电流密度、0.5 m Ah cm^-2锂沉积量条件下, C(PAN)-Li0.47WO2.89复合纤维膜经过1000次充放电循环后库仑效率仍高达99.4%,而铜集流体和C(PAN)纤维膜集流体在100和800次循环后,库仑效率已经分别降至8.5%和64.6%.本研究为高性能金属锂电池开发提供了新的设计思路.Polyacrylonitrile-lithium tungsten bronze(PAN-Li0.47WO2.89) composite fiber membranes are prepared by electrospinning and then pre-oxidized and carbonized to obtain lithium tungsten bronze modified polyacrylonitrile-based composite carbon fiber membrane current collectors(C(PAN)-Li0.47WO2.89). The composite fiber membranes offer the attractive advantages of high electrical conductivity and large specific surface area(52.84 m^2 g^-1), reducing the amount of surface lithium deposition and deposition current density.Additionally, introducing lithiophilic Li0.47WO2.89 into the fibers, effectively improves the reversibility and uniformity of the lithium deposition-stripping reaction by reducing nucleation overpotential and increasing nuclei density. With these benefits, the C(PAN)-Li0.47WO2.89 composite fibers demonstrate a high coulombic efficiency of 99.4% even after 1000 cycles(0.5 mA cm^-2 current density and 0.5 m Ah cm^-2 lithium deposition capacity);whereas, the coulombic efficiency of copper foil and C(PAN)fiber current collectors is only 8.5% and 64.6% after 100 and 800 cycles, respectively. This study provides a new approach for the development of highperformance metal lithium batteries.

关 键 词：碳纤维 Li0.47WO2.89 锂钨青铜 金属锂负极 锂离子电池 锂枝晶 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ340.64[化学工程—化纤工业] TB33[一般工业技术—材料科学与工程]