二次可充放电电池用硒化锡负极材料的研究现状

Recent Progress of Secondary Rechargeable/discharged Battery Tin Selenide Anode Materials

硒化锡(SnSe、SnSe 2)因其特殊的层状晶体结构以及较高的导电性,有望成为锂/钠离子电池的负极材料。但是硒化锡负极在充放电过程中体积会反复变化,导致电极结构及表面SEI膜(电极与电解液界面)遭到破坏,使活性材料失去电接触,从而导致循环容量迅速衰减;此外,硒化锡转化反应中间产物Li 2Se/Na 2Se的导电性较差,阻碍了电荷的传输,从而影响了硒化锡电极的电化学反应活性。本文针对硒化锡电极在储锂/钠过程中存在的问题,总结了提升其电化学性能的手段,并概述了国内外学者从构建特殊纳米结构和复合结构等层面上采取的解决办法,揭示了其电化学存储机制以及能够获得的电化学性能。

Tin selenide(SnSe,SnSe 2)is considered to be a kind of potential lithium/sodium ion battery anode materials due to its special layered crystal structure and high electrical conductivity.However,tin selenide materials still exist several issues during lithium/sodium ions storage process.On the one hand,the huge volumetric change of tin selenide anode can result in the destruction of electrode structure and SEI film(solid-electrolyte interface film).This cracked structure without good electric contact will lead to rapid decay of the cycling performance.On the other hand,the electrical conductivity of intermediate products Li 2Se/Na 2Se is poor,hindering the charge transfer and lowering the electrochemical reaction kinetics of tin selenide electrode.Based on the issues in lithium/sodium ions storage process,we summarize several strategies that have been used to enhance the electrochemical property of tin selenide,and review the domestic and foreign scholars from build special nano structure and composite structure level to reveal the electrochemical storage mechanism as well as the improved electrochemical performance.