正极材料Li_3V_2(PO_4)_3溶胶-凝胶法合成及其电化学性能

Synthesis of Li_3V_2(PO_4)_3 cathode material by a sol-gel method and its electrochemical characteristics

以LiO H·H 2O、N H 4V O 3、N H 4H 2P O 4和柠檬酸为原料,采用溶胶-凝胶法制备了正极材料Li3V 2(P O 4)3。研究了焙烧温度、焙烧时间和测试温度对产物电化学性能的影响。通过X射线衍射(X R D)和扫描电镜(S E M)分别对材料的晶体结构和形貌进行表征。结果表明,在850℃焙烧8 h所得材料具有良好的电化学性能。在测试温度为55℃,0.2 C条件下,材料的首次放电比容量达到121.78 m A h/g,循环30次后,放电比容量仍然保持在115.90 m A h/g。

Li3V2（PO4）3 cathode material was prepared by a sol-gel method with LiOH.H20, NH4VO3, NH4H2PO4 and citric acid. The effects of sintering temperatures, times and testing temperatures on the product were investigated. The crystal structure and morphology of the material were characterized by XRD and SEM. The results show the material prepared at 850 ~C for 8 h has excellent electrochemical performance. At the testing temperature of 55 ~C, it demonstrates that the first discharge specific capacity of the product is 121.78 mAh/g at 0.2 C rate and the discharge capacity remains 115.90 mAh/g after 30 cycles.