Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
11001504 | Electrochimica Acta | 2018 | 16 Pages |
Abstract
Lithium vanadium fluorophosphate (LiVPO4F) composite with three-dimensional conductive networks architecture is synthesized with synergistic modification of pyrolytic carbon (C), multi-walled carbon nanotubes (MWCNTs) and graphene sheets (rGO). The differences between LiVPO4F@C, LiVPO4F@C/MWCNTs, LiVPO4F@C/rGO and LiVPO4F@C/MWCNTs/rGO composites are compared through a variety of characterization means. By means of SEM and TEM analysis, it can be seen that pyrolyzed C, MWCNTs and rGO are interwoven, which forms a three-dimensional conductive network structure wrapping the LiVPO4F particles. The difference of discharge specific capacity between LiVPO4F@C and LiVPO4F@C/MWCNTs/rGO composites is becoming larger and larger with the increase of charge-discharge rate. Additionally, CV and EIS results indicate that the LiVPO4F@C/MWCNTs/rGO has the smallest polarization value and charge transfer impedance (Rct) as well as the highest diffusion coefficient of lithium ion (DLi+) in all samples. Consequently, LiVPO4F@C/MWCNTs/rGO composite exhibits a high rate capability (97.9â¯mAh/g cycles at 10â¯C) and cycling stability (93.74% capacity retention over 800 cycles at 10â¯C)ï¼showing potential application for high power LIB with high voltage.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Chemical Engineering (General)
Authors
Guorong Hu, Zhanggen Gan, Yanbing Cao, Ke Du, Yao Du, Zhongdong Peng,