Acta Phys. -Chim. Sin. ›› 2017, Vol. 33 ›› Issue (11): 2261-2267.doi: 10.3866/PKU.WHXB201705293

• ARTICLE • Previous Articles     Next Articles

Synthesis and Electrochemical Performance of Alginic Acid-Based Carbon-Coated Li3V2(PO4)3 Composite by Rheological Phase Method

Wan-Long LI1,Yue-Jiao LI1,*(),Mei-Ling CAO1,Wei QU1,Wen-Jie QU1,Shi CHEN1,2,Ren-Jie CHEN1,2,*(),Feng WU1,2   

  1. 1 Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China
    2 Collaborative Innovation Center of Electric Vehicles in Beijing, Beijing 100081, P. R. China
  • Received:2017-03-27 Published:2017-08-25
  • Contact: Yue-Jiao LI,Ren-Jie CHEN E-mail:lyj@bit.edu.cn;chenrj@bit.edu.cn
  • Supported by:
    National Key Research and Development Program of China(2016YFB0100204);National Natural Science Foundation of China(21373028);Joint Funds of the National Natural Science Foundation of China(U1564206);Major achievements Transformation Project for Central University in Beijing, Beijing Science and Technology Project(D151100003015001)

Abstract:

Li3V2(PO4)3/C (LVP/C) cathode materials were successfully prepared by a rheological phase method using alginic acid as the carbon source. The X-ray diffraction (XRD) patterns demonstrate that all the samples contain pure LVP with the same monoclinic structure. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images show that LVP/C materials have a uniform particle size. The LVP/C sample with 10% (w) alginic acid shows the best cycling stability. It delivers a discharge capacity of 117.5 mAh·g-1 (3.0-4.3 V), which can be maintained at 116.5 mAh·g-1 after 50 cycles at a rate of 0.1C. Its capacity retentions of 99.1% (3.0-4.3 V) and 76.8% (3.0-4.8 V) after 50 cycles are prominently higher than those of pristine Li3V2(PO4)3, which are 89.7% (3.0-4.3 V) and 62.39% (3.0-4.8 V). These outstanding electrochemical performances are mainly attributed to the alginic acid-based carbon coating, which can increase the electronic conductivity of materials and buffer the mechanical damage of the active materials during the Li ion insertion/extraction process, thus improving the electrochemical performance of the LVP/C samples.

Key words: Lithium ion battery, Rheological phase method, Alginic acid, Li3V2(PO4)3/C composite

MSC2000: 

  • O646