Li Malin, Gao Yu, Chen Nan, Meng Xing, Wang Chunzhong, Zhang Yaoqing, Zhang Dong, Wei Yingjin, Du Fei, Chen Gang
Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun, 130012, P. R. China.
State Key Laboratory of Superhard Materials, Jilin University, Changchun, 130012, P. R. China.
Chemistry. 2016 Aug 1;22(32):11405-12. doi: 10.1002/chem.201601423. Epub 2016 Jun 30.
Cu3 V2 O8 nanoparticles with particle sizes of 40-50 nm have been prepared by the co-precipitation method. The Cu3 V2 O8 electrode delivers a discharge capacity of 462 mA h g(-1) for the first 10 cycles and then the specific capacity, surprisingly, increases to 773 mA h g(-1) after 50 cycles, possibly as a result of extra lithium interfacial storage through the reversible formation/decomposition of a solid electrolyte interface (SEI) film. In addition, the electrode shows good rate capability with discharge capacities of 218 mA h g(-1) under current densities of 1000 mA g(-1) . Moreover, the lithium storage mechanism for Cu3 V2 O8 nanoparticles is explained on the basis of ex situ X-ray diffraction data and high-resolution transmission electron microscopy analyses at different charge/discharge depths. It was evidenced that Cu3 V2 O8 decomposes into copper metal and Li3 VO4 on being initially discharged to 0.01 V, and the Li3 VO4 is then likely to act as the host for lithium ions in subsequent cycles by means of the intercalation mechanism. Such an "in situ" compositing phenomenon during the electrochemical processes is novel and provides a very useful insight into the design of new anode materials for application in lithium-ion batteries.
采用共沉淀法制备了粒径为40 - 50 nm的Cu3 V2 O8纳米颗粒。Cu3 V2 O8电极在前10个循环中的放电容量为462 mA h g(-1) ，令人惊讶的是，50个循环后比容量增加到773 mA h g(-1) ，这可能是由于通过固体电解质界面（SEI）膜的可逆形成/分解实现了额外的锂界面存储。此外，该电极在1000 mA g(-1) 的电流密度下具有良好的倍率性能，放电容量为218 mA h g(-1) 。此外，基于不同充放电深度的非原位X射线衍射数据和高分辨率透射电子显微镜分析，解释了Cu3 V2 O8纳米颗粒的锂存储机制。结果表明，Cu3 V2 O8在首次放电至0.01 V时分解为金属铜和Li3 VO4 ，随后Li3 VO4可能通过嵌入机制在后续循环中作为锂离子的宿主。这种在电化学过程中的“原位”复合现象是新颖的，为锂离子电池新型负极材料的设计提供了非常有用的见解。
