物理化学学报 >> 2004, Vol. 20 >> Issue (04): 377-381.doi: 10.3866/PKU.WHXB20040409

研究论文 上一篇    下一篇

利用湿法反应制备的LiV3O8的锂离子扩散特性

刘恩辉;李新海;侯朝辉;何则强;邓凌峰   

  1. 中南大学冶金科学与工程学院,长沙 410083
  • 收稿日期:2003-10-06 修回日期:2003-11-28 发布日期:2004-04-15
  • 通讯作者: 刘恩辉 E-mail:liuenhui99@sina.com.cn

Chemical Diffusion Behaviors of Lithium-ion in the LiV3O8 Prepared by Wet Method Reaction

Liu En-Hui;Li Xin-Hai;Hou Zhao-Hui;He Ze-Qiang;Deng Ling-Feng   

  1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083
  • Received:2003-10-06 Revised:2003-11-28 Published:2004-04-15
  • Contact: Liu En-Hui E-mail:liuenhui99@sina.com.cn

摘要: 利用V2O5•nH2O湿凝胶和Li2CO3作原料,通过溶液反应和低温焙烧的方法合成了用于锂离子电池正极的LiV3O8.对其前驱体和产品分别进行DTA-TG、XRD表征.LiV3O8用作锂离子电池正极的电化学性能利用恒电流充放电测试进行研究.实验表明活性材料LiV3O8具有较高的充放容量和良好的循环性能.LiV3O8电极的锂离子化学扩散系数由恒电位间歇滴定技术(PITT)来确定,其值依据Li1+xV3O8中x值的不同在10-8~10-10 cm2•s-1的变化范围内.获得的锂离子的扩散活化能为:Ea=25~42 kJ•mol-1(x=0.18~2.5).认为锂离子扩散的最大活化能是由锂离子在Li4V3O8相中的扩散决定的.

关键词: 三钒酸锂, 湿法反应, 扩散, 活化能, 锂离子电池

Abstract: LiV3O8 as a cathode material for lithium ion batteries was synthesized by solution reaction and low temperature calcinations technique with V2O5•nH2O hydro-gels and Li2CO3 as raw materials. The precursor and product were characterized by DTA-TG, XRD measurements. Electrochemical behavior of the LiV3O8 as a cathode material for rechargeable lithium-ion batteries was studied by galvanostatic charge-discharge measurement. The experiment showed that the active material LiV3O8 was of higher charge-discharge capacity and excellent cycling behavior. Lithium-ion chemical diffusion coefficient (DLi+) of the LiV3O8 electrode was determined by the potentiostatic intermittent titration technique (PITT).DLi+ values obtained were in the range of 10-8~10-10 cm2•s-1,depending on x-values in Li1+xV3O8.The activation energy of lithium-ion diffusion (Ea) obtained was in the range of 25~42 kJ•mol-1(x=0.18~2.5).

Key words: Lithium trivanadate, Wet method reaction, Diffusion, Activation energy,  Lithium-ion battery