溶胶-凝胶法合成锂离子电池正极材料Li_(1+x)V_3O_8的初步探讨

采用溶胶-凝胶法合成锂离子电池正极材料Li1+xV3O8,并用X射线衍射、扫描电镜观察、充放电循环测试、循环伏安法扫描等,研究了Li1+xV3O8的物相结构、表面形貌以及电化学性能等,并探索了合成工艺条件对材料的电化学性能的影响。结果表明,温度为400℃时合成的Li1+xV3O8晶粒较为细小均匀,粒径大小相对较为均一,颗粒大小在0.5—1.0μm左右,这些小晶粒将有效地增加其比表面积,同时电化学性能较好,10mA/g的电流密度下首次放电容量为230 mAh/g,20次循环之后容量仍能达到180 mAh/g,循环性能较好。随着合成温度增高,首次放电容量减小,循环效率降低。

Sol-gel Synthesis and Electrochemical Performance of Li1+xV3O8 Cathode Material for Lithium-ion Battery

Lithium-ion battery cathode material Li1+xV3O8 was synthesized through sol-gel method with Li2CO3 and NH4VO3 as raw materials.The Li1+xV3O8 was characterized by means of XRD,SEM and CV.The electrochemical properties of the product under different conditions were investigated.The results indicated that the prepared layered structure Li1+xV3O8 exhibits good electrochemical behavior,and the electrochemical properties of the sample sintered at 400 ℃ for 12 h reaches the best.The particle is relatively uniform with size about 0.5—1.0 μm.These small grains will increase specific surface area effectively.The first discharge capacity is 230 mAh/g with a current density of 10 mA/g,and maintains a discharge capacity of 180 mAh/g after 20 cycles,showing good cycle performance.At the same time,as the synthesis temperature rises,the initial discharge capacity decreases,so does the cycle efficiency.