中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 20 No. 4 April 2010 |
（1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of New Processing Technology for Nonferrous Metals and Materials, Ministry of Education,
Guilin University of Technology, Guilin 541004, China;
3. Guangxi Key Laboratory of Environmental Engineering, Protection and Assessment,
Guilin University of Technology, Guilin 541004, China;
4. College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China;
5. Hunan Institute of Humanities, Science and Technology, Loudi 417000, China）
Abstract:The effect of Al-substitution on the electrochemical performances of Li3V2(PO4)3 cathode materials was studied. Samples with stoichiometric proportion of Li3AlxV2−x(PO4)3 (x=0, 0.05, 0.10) were prepared by adding Al(NO3)3 in the raw materials of Li3V2(PO4)3. The XRD analysis shows that the Al-substituted Li3V2(PO4)3 has the same monoclinic structure as the un-substituted Li3V2(PO4)3. The SEM images show that Al-substituted Li3V2(PO4)3 has regular and uniform particles. The electrochemical measurements show that Al-substitution can improve the rate capability of cathode materials. The Li3Al0.05V1.95(PO4)3 sample shows the best high-rate performance. The discharge capacity at 1C rate is 119 mA∙h/g with 30th capacity retention rate about 92.97%. The electrode reaction reversibility and electronic conductivity are enhanced, and the charge transfer resistance decreases through Al-substitution. The improved electrochemical performances of Al-substituted Li3V2(PO4)3 cathode materials offer some favorable properties for their commercial application.
Key words: lithium ion batteries; cathode material; Li3V2(PO4)3; electrochemical performance; sol-gel method
