摘要
锂硫电池因其超高的理论比容量(1675 mA·h/g)和能量密度(2600 W·h/kg),已成为目前锂电池研究的热点和重点。但是,锂硫电池的发展依然受到很多因素的制约。其中,穿梭效应是造成锂硫电池性能衰减的主要原因之一:一方面,大量中间产物多硫化锂溶解在电解液中以及不溶性产物Li_2S_2/Li_2S沉积在负极上,降低了活性物质的利用率,造成电池容量衰减;另一方面,穿梭会导致充电时电池发生严重过充,降低库仑效率;此外,穿梭还会引起金属锂表面的腐蚀反应。本文介绍了锂硫电池的穿梭机理,从物理作用和化学作用两方面综述了近年来锂硫电池中抑制穿梭效应的研究进展,具体涉及正极、电解质、负极等关键材料的设计与优化,并着重介绍了物理作用抑制穿梭的进展情况,最后简要评述了锂硫电池的研究现状并对其未来进行了展望。
Lithium sulfur batteries, because of their high theoretical specific capacity -1675mA·h·g^-1 and energy density -2600 W·h·kg^-1, have become the hotspot and keystone of the researches on the next-generation energy storage. Dissolution and the consequent shuttle effect are the main challenges of lithium sulfur batteries which seriously hinder the real application of the batteries. The high solubility of polysulfides in electrolytes generated during the charge-discharge process, results in severe loss of specific capacity. The Li2S2/Li2S deposited on lithium anode also decreases the utilization of active sulfur. Meanwhile, the shuttle is considered as the major reason for the low coulombic efficiency. This review discussed the shuttle mechanism and introduced the recent research progress in physical or chemical shuttle suppression, including the designs related with the cathode, electrolyte and anode. The future research directions and perspective of lithium sulfur batteries were also described.
出处
《储能科学与技术》
CAS
CSCD
2017年第5期1026-1040,共15页
Energy Storage Science and Technology
基金
国家自然科学基金(51402330
51472261
51372262)
上海市科学技术委员会项目(15DZ2281200)
关键词
锂硫电池
穿梭效应
正极
电解质
负极
lithium sulfur batteries
shuttle
cathode
electrolyte
anode
