高等学校化学学报 ›› 2014, Vol. 35 ›› Issue (2): 362.doi: 10.7503/cjcu20130599

• 物理化学 • 上一篇    下一篇

水热法制备富锂型Li2+4xMn0.6+2xNi0.6-6xCr0.8O4及其结构与电化学特性

赵利芳1, 张茜2, 贺诗词3, 刘伟伟2, 杨裕生4, 郑军伟2, 潘勤敏1, 李德成2()   

  1. 1. 苏州大学材料与化学化工学部, 苏州 215123
    2. 苏州大学江苏省锂离子电池材料重点实验室, 化学电源研究所, 苏州 215006
    3. 安徽省阜阳市产品质量监督检验所, 阜阳 236000
    4. 北京防化研究院, 北京 100083
  • 收稿日期:2013-06-27 出版日期:2014-02-10 发布日期:2013-09-02
  • 作者简介:联系人简介: 李德成, 男, 博士, 教授, 主要从事锂离子电池材料研究. E-mail:lidecheng@suda.edu.cn
  • 基金资助:
    国家自然科学基金(批准号: 20973200)资助

Structure and Electrochemical Properties of Li-rich Li2+4xMn0.6+2xNi0.6-6xCr0.8O4 Spinel Prepared by Hydrothermal Method

ZHAO Lifang1, ZHANG Qian2, HE Shici3, LIU Weiwei2, YANG Yusheng4, ZHENG Junwei2, PAN Qinmin1, LI Decheng2,*()   

  1. 1. College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
    2. Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of Chemical Power Sources,Soochow University, Suzhou 215006, China
    3. Fuyang Product Quality Supervision and Inspection Institution, Fuyang 236000, China
    4. Research Institute of Chemical Defense, Beijing 100083, China
  • Received:2013-06-27 Online:2014-02-10 Published:2013-09-02
  • Contact: LI Decheng E-mail:lidecheng@suda.edu.cn
  • Supported by:
    † Supported by the National Natural Science Foundation of China(No.20973200)

摘要:

采用水热法制备了系列富锂尖晶石型正极材料Li2+4xMn0.6+2xNi0.6-6xCr0.8O4(x=1/30, 1/20, 1/15, 1/12), 通过X射线衍射(XRD)、 电感耦合等离子体-原子发射光谱(ICP-AES)、 扫描电子显微镜(SEM)、 X射线光电子能谱 (XPS)、 傅里叶变换红外光谱(FTIR)、 拉曼光谱、 循环伏安(CV)和充放电测试等手段对其结构及电化学性能进行表征. 结果表明, 所制备的系列材料为富锂型高电压尖晶石结构正极材料, 该系列样品在4.7 V左右有放电平台. x=1/15和x=1/12时, 样品中的Cr为+3价, 没有观测到Cr6+. 随着x值的增大, 样品中Li离子与过渡金属离子的混排减小, 样品的充放电比容量逐渐增大, 且2.7 V处的放电平台容量也增加. 当x=1/12时, 样品具有较好的充放电比容量和倍率特性, 首次放电比容量为107.3 mA·h/g, 20次循环后容量保持率为84.9%.

关键词: 锂离子电池, 正极材料, 富锂尖晶石结构, 水热法, 高电压

Abstract:

A series of cathode materials, Li2+4xMn0.6+2xNi0.6-6xCr0.8O4(x=1/30, 1/20, 1/15, 1/12), was prepared via hydrothermal method, and their composition, structure and electrochemical properties were investigated using X-ray diffraction(XRD), inductively coupled plasma-atomic emission spectrometry(ICP-AES), scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS), Fourier transform infrared spectrometry(FTIR), Raman spectrometry and charge-discharge tests. XRD measurements combining with ICP results reveal that the obtained samples are Li-rich type spinel structure. Moreover, XPS results suggest that the valence for Cr is +3 for x=1/15 and 1/12 and no Cr6+ exist. As to their electrochemical properties, it is found that these materials have a high-voltage plateau near 4.7 V and a low-voltage near 2.7 V. With the increase of x value, both charge and discharge capacities of the samples increase. The sample with x=1/12 shows a good cyclic performance as well as good rate capability.

Key words: Lithium ion battery, Cathode material, Li-rich spinel structure, Hydrothermal method, High-voltage

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