摘要
金属锂具有超高理论比容量密度(3680 mA·h/g)和低还原电位(-3.04 V,相对标准氢电极),被认为是高能量密度电池负极材料的“圣杯”。然而,由锂枝晶生长和对电解质高反应性所造成的库仑效率低、循环寿命短、内短路等一系列问题,严重制约着金属锂负极的实用化进展。在实际的电化学体系中,集流体作为金属锂沉积/脱出的基底,其表面性质对锂负极的循环稳定性起着至关重要的作用。本文从负极集流体表面成分以及微结构设计两方面系统总结了多种稳定金属锂负极的界面修饰策略,包括构建亲锂表面、纳米级电子/离子混合导电网络修饰、表面微结构设计等。对集流体界面和结构进行针对性修饰,可以有效调控金属锂的电沉积,推进金属锂负极在高能量密度电池体系中的实用化进程。
Because of the ultra-high theoretical capacity density(3680 m A·h·g-1) and the low reduction potential(-3.04 V versus the standard hydrogen electrode), metallic Li is considered the "Holy Grail" anode material for high energy density battery systems. However, a series of problems such as low Coulombic efficiency, short cycle life, and internal short circuits caused by Li dendritic growth and high reactivity toward electrolytes hinder the practical utilization of Li metal anodes. In a practical electrochemical system, the current collector is the substrate for the plating and stripping of Li. Therefore, its surface properties play a vital role on the cyclic stability of the Li metal anode. In this study, multiple strategies of surface modification and microstructure design on current collectors to stabilize Li metal anodes are systematically summarized, including the fabrication of lithophilic surfaces, the modification of nanoscale electronic/ionic hybrid conductive networks, and the design of surface microstructures.Targeted interface/structure modifications of the current collector can effectively regulate the electrodeposition of Li and promote the practical application of Li metal anodes in high energy density battery systems.
作者
刘洋洋
王旭阳
徐谢宇
王永静
熊仕昭
宋忠孝
LIU Yangyang;WANG Xuyang;XU Xieyu;WANG Yongjing;XIONG Shizhao;SONG Zhongxiao(State Key Laboratory for Mechanical Behavior of Materials,Xi'an Jiaotong University,Xi'an 710049,Shaanxi,China)
出处
《储能科学与技术》
CAS
CSCD
北大核心
2021年第4期1261-1272,共12页
Energy Storage Science and Technology
基金
国家自然科学基金项目(51802256)。
关键词
集流体
金属锂负极
亲锂表面
锂枝晶
表面微结构
current collector
lithium metal anode
lithophilic surface
lithium dendrites
surface microstructure
