物理化学学报 >> 2011, Vol. 27 >> Issue (03): 609-614.doi: 10.3866/PKU.WHXB20110241

电化学和新能源 上一篇    下一篇

纺锤体形LiFePO4锂离子电池正极材料的制备与性能

苏畅, 陆国强, 徐立环, 张诚, 马淳安   

  1. 浙江工业大学, 绿色化学合成技术国家重点实验室培育基地, 杭州 310014
  • 收稿日期:2010-10-18 修回日期:2010-11-24 发布日期:2011-03-03
  • 通讯作者: 张诚 E-mail:czhang@zjut.edu.cn
  • 基金资助:

    国家自然科学基金(51003095)和浙江省公益性技术应用研究计划(2010C31121)资助项目

Synthesis and Properties of Spindle-Shaped LiFePO4 for the Cathode Material of Lithium Ion Battery

SU Chang, LU Guo-Qiang, XU Li-Huan, ZHANG Cheng, MA Chun-An   

  1. State Key Laboratory Breeding Base for Green Chemistry Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014, P. R. China
  • Received:2010-10-18 Revised:2010-11-24 Published:2011-03-03
  • Contact: ZHANG Cheng E-mail:czhang@zjut.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (51003095) and Research on Public Welfare Technology Application Projects of Zhejiang Province, China (2010C31121).

摘要:

采用低温溶剂热法合成了LiFePO4, 并通过热处理方法制备出LiFePO4/C锂离子电池复合正极材料. 利用扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、傅里叶变换红外(FTIR)光谱以及恒电流充放电测试等方法对样品进行结构表征和充放电性能测试. 结果表明: 采用丙三醇(甘油)为溶剂, 低温条件下(120 °C)合成的LiFePO4具有橄榄石型晶体结构, 呈纺锤体形貌, 且具有粒径分布均匀的特点. 热处理后制备的LiFePO4/C复合正极材料仍呈纺锤体形貌, 且表现出了优良的充放电性能. 室温下以0.1C倍率恒流充放电, LiFePO4/C的首次放电比容量达到147.2 mAh·g-1, 50次循环后放电比容量仍然保持在136.3 mAh·g-1. 当倍率为0.2C、0.5C和1C时, 样品的平均放电比容量分别在130、120和108 mAh·g-1左右.

关键词: 锂离子电池, LiFePO4, 纺锤体形, 溶剂热法, 充放电性能

Abstract:

We synthesized LiFePO4 directly by a solvothermal method at low temperature and then a heat treatment was carried out to give a LiFePO4/C composite for using as a cathode in lithium ion battery. The crystal structure and the charge-discharge performance of the prepared samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and galvanostatic charge-discharge testing. The results indicated that the LiFePO4 synthesized at low-temperature (120 °C) with glycerol as a solvent had a single olivine-type crystal structure and a spindle-shaped morphology with a very narrow size distribution. After heat treatment, a LiFePO4/C composite with excellent charge-discharge performance was obtained and the spindle morphology of the sample was intact. Galvanostatic charge-discharge tests showed that the prepared LiFePO4/C cathode had an initial discharge specific capacity of 147.2 mAh·g-1 at 0.1C at room temperature and it was 136.3 mAh·g-1 after 50 cycles. The average discharge specific capacities of LiFePO4/C at 0.2C, 0.5C, and 1C were about 130, 120, and 108 mAh·g-1, respectively.

Key words: Lithium ion battery, LiFePO4, Spindle-shaped, Solvothermal method, Charge-discharge performance

MSC2000: 

  • O646