锂离子电池SnS_2基负极材料

SnS_2 Based Anode Materials for Lithium-Ion Batteries

随着应用范围的逐渐扩大,锂离子电池对具有高比容量、长循环寿命以及优异倍率性能的新型正负极材料的需求日益迫切。SnS2材料因具有独特的层状结构和高的理论比容量而被视作潜在的高比容量负极材料,但其也存在首次不可逆容量较大、导电率低、充放电过程中体积变化较大等问题。本文综述了SnS2负极材料的研究历程以及最新研究进展,介绍了SnS2负极材料的基本性质,具体论述了SnS2电化学性能改进的相关措施,主要包括控制纳米SnS2微观形貌、制备SnS2/C及SnS2/氧化物复合材料、掺杂、一体化电极以及优化粘结剂等。文章同时总结了水热(溶剂热)法各工艺参数(原料种类、浓度、比例、溶液pH值、水热温度及时间等)对制备SnS2纳米材料及SnS2/C复合材料形貌结构及电化学性能的影响,并对目前SnS2材料仍然存在的问题进行了分析。研究表明,通过制备片状、花状等高比表面积的SnS2纳米材料,可明显提升其循环性能;将石墨烯等碳材料与SnS2复合,有助于提高材料的结构稳定性及导电性,进而改善电极的循环及倍率性能。经工艺优化后的SnS2/graphene复合材料具有高的比容量(大于1000 mAh/g)、稳定的循环性能和优秀的倍率特性,是一种非常有研究价值的高比容量锂离子电池负极材料。

With the expanding of lithium-ion battery applications,novel cathode /anode materials with high capacity,long cycle life and excellent rate capability are in great demand. SnS2 is deemed to be one of potential alternative anode materials for its unique layer structure and high theoretical capacity. However,it suffers from large initial irreversible capacity,low electrical conductivity and huge volume change during charge /discharge process,which limit its practical application. In the present paper,the development history and latest progress of SnS2 anode material are reviewed. The basic properties of SnS2 are described. The approaches for improving the electrochemical performance of SnS2 are summarized,including micromorphology control of nanoparticles,preparation of SnS2/C and SnS2/oxide composites,bulk-doping,making integrative electrode,optimizing binder,etc. The influences of processing parameters（raw material, concentration, ratio, pH value,hydrothermal temperature and time） of hydrothermal（solovthermal） methods on the structure and electrochemical performance of the prepared SnS2 and SnS2/C composites are expounded. Besides,the problems associated with SnS2 anode materials are also discussed. Nanostructured SnS2 with high specific area,such as sheet- and flowerlike-shaped particles,is proved to be beneficial for cycle performance. Compositing SnS2 with different kinds of carbon can enhance the structure stability as well as electrical conductivity,and hence improve the cycle performance and rate capability of electrode. The optimized SnS2/graphene composite exhibits high specific capacity（over 1000 mAh /g）,stable cycling performance and excellent rate capability,which make it a promising high capacity anode material for lithium-ion batteries.