石墨烯应用于锂硫电池的研究进展

Recent advances in graphene materials used in Li-S batteries

锂硫电池具有很高的理论放电比容量(1675 mAh/g)和能量密度(2600 Wh/kg),被认为是最具前景的新型电池之一。石墨烯具有优良的导电性和电化学性能,具有开阔的负载硫的表面和空间,是导电性差的硫黄和硫化锂的良好载体,为锂硫电池正极材料提供了新的研发平台。本文介绍了近年来石墨烯及其复合材料应用于锂硫电池中的研究进展,包括石墨烯或氧化石墨烯负载硫、杂原子掺杂石墨烯负载硫、石墨烯三维网格负载硫和石墨烯-多孔炭复合炭材料负载硫等4种石墨烯基-硫正极材料,概述了其锂硫电池的比容量、倍率性能和循环寿命等性能指标。从石墨烯基锂硫电池正极材料的设计和合成的角度,总结了不同微结构特征的石墨烯及其复合材料组装成锂硫电池的性能特点,并分析了材料组成和微结构对电池性能的影响机制。在总结的基础上展望了石墨烯应用于锂硫电池的发展方向。

The lithium-sulfur battery is considered one of the most promising next-generation secondary batteries owing to its high theoretical specific capacity(1675 mAh/g)and high energy density(2600 Wh/kg).Graphene has excellent electrical conductivity,a high surface area and open space as well as an excellent electrochemical performance,and is considered the ideal platform for loading low-conductivity sulfur and lithium sulfide for the use as the cathodes of lithium-sulfur batteries.This article summarizes recent developments on graphene and graphene-based materials for lithium-sulfur batteries,including nanocomposites of sulfur with(reduced)graphene oxide,heteroatom-doped graphene,three-dimensional graphene foams and graphene-porous carbon.The impact of these graphene-based nanocomposites with various compositions and microstructures on improvements in the performance and mechanism of lithium-sulfur batteries are discussed.Prospects for lithium-sulfur battery development are outlined.