材料期刊网

V2 O5具有独特的层状结构,适合于锂离子的存储,与传统的锰酸锂、钴酸锂、磷酸铁锂等阴极材料相比,表现出高的理论比容量和功率密度,作为锂离子电池阴极材料备受青睐。但它自身的结构不稳定、电导率低,导致实际比容量远低于理论值,且循环稳定性不能长期维持。正是由于这些制约因素,V2 O5作锂离子电池阴极材料还有很大的研究价值。而利用各种制备方法将 V2 O5制备成具有各种纳米结构的材料,如一维的纳米线、纳米管等,二维的纳米片,三维的纳米空心球、纳米花等,改善材料固有的形貌结构,增大比表面积,增强锂离子在电极材料中的嵌入/脱出性能,提高储锂能力和比容量,同时通过掺杂改性等方法增强材料的导电性和循环稳定性,使 V2 O5作为锂离子电池阴极材料表现出优异的电化学性能成为可能。介绍了 V2 O5的晶体结构及其作为电极材料的纳米结构,以及不同的纳米结构对电极材料电化学性能的影响。

V2 O5 is suitable for lithium ion storage due to its unique layered structure,which exhibits high theo-retical specific capacity and excellent power density compared to traditional LiMn2 O4 ,LiCoO2 and LiFePO4 cathode materials etc.,so it has become widely accepted as the cathode material for lithium-ion batteries.However,its own unstable structure and low conductivity result in an actual capacity much lower than theoretical value,and the rapid at-tenuation of cycle stability.Because of these restricting factors,vanadium pentoxide material is worthy of further studies.V2 O5 crystals are turned into materials with various nanostructures through various preparation methods,in-cluding one-dimensional nanowires and nanotubes,two-dimensional nanosheets,three-dimensional hollow nanospheres and nanoflowers etc.,which improve its inherent structural morphology,increase its surface area and enhance lithia-tion and de-lithiation performance in lithium-ion battery,increase lithium storage capacity and improve its specific ca-pacity.Meanwhile,methods of doping and modification are adopted to enhance its conductivity and cycle stability, conferring excellent electrochemical performance to V2 O5 for cathode materials of lithium ion battery.Herein,a vivid description upon the crystal structure of V2 O5 ,the corresponding nanostructures of electrode material and their influe-nces on electrochemical performances are proposed.