能源化学(英文) ›› 2014, Vol. 23 ›› Issue (3): 363-375.DOI: 10.1016/S2095-4956(14)60159-5

• ARTICLES • 上一篇    下一篇

3D amorphous carbon and graphene co-modified LiFePO4 composite derived from polyol process as electrode for high power lithium-ion batteries

Guan Wua,c, Ran Rana, Bote Zhaoa, Yujing Shaa, Chao Sub, Yingke Zhoua, Zongping Shaoa,b   

  1. a. State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry & Chemical Engineering, Nanjing University of Technology, Nanjing 210009, Jiangsu, China;
    b. Department of Chemical Engineering, Curtin University, Perth, WA 6845, Australia;
    c. Ningde Amperex Technology Limited, Ningde 352100, Fujian, China
  • 收稿日期:2013-11-07 修回日期:2014-01-21 出版日期:2014-05-24 发布日期:2014-05-25
  • 通讯作者: Zongping Shao
  • 基金资助:

    This work was partially supported by the National Science Foundation for Distinguished Young Scholars of China (No. 51025209), the National Nature Science Foundation of China (No. 21103089), and the Key Projects in Nature Science Foundation of Jiangsu Province (No. BK2011030).

3D amorphous carbon and graphene co-modified LiFePO4 composite derived from polyol process as electrode for high power lithium-ion batteries

Guan Wua,c, Ran Rana, Bote Zhaoa, Yujing Shaa, Chao Sub, Yingke Zhoua, Zongping Shaoa,b   

  1. a. State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry & Chemical Engineering, Nanjing University of Technology, Nanjing 210009, Jiangsu, China;
    b. Department of Chemical Engineering, Curtin University, Perth, WA 6845, Australia;
    c. Ningde Amperex Technology Limited, Ningde 352100, Fujian, China
  • Received:2013-11-07 Revised:2014-01-21 Online:2014-05-24 Published:2014-05-25
  • Supported by:

    This work was partially supported by the National Science Foundation for Distinguished Young Scholars of China (No. 51025209), the National Nature Science Foundation of China (No. 21103089), and the Key Projects in Nature Science Foundation of Jiangsu Province (No. BK2011030).

摘要: Amorphous carbon and graphene co-modified LiFePO4 nanocomposite has been synthesized via a facile polyol process in connection with a following thermal treatment. Various characterization techniques, including XRD, Mössbauer spectra, Raman spectra, SEM, TEM, BET, O2-TPO, galvano charge-discharge, CV and EIS were applied to investigate the phase composition, carbon content, morphological structure and electrochemical performance of the synthesized samples. The effect of introducing way of carbon sources on the properties and performance of LiFePO4/C/graphene composite was paid special attention. Under optimized synthetic conditions, highly crystalized olivine-type LiFePO4 was successfully obtained with electron conductive Fe2P and FeP as the main impurity phases. SEM and TEM analyses demonstrated the graphene sheets were randomly distributed inside the sample to create an open structured LiFePO4 with respect to graphene, while the glucose-derived carbon mainly coated over LiFePO4 particles which effectively connected the graphene sheets and LiFePO4 particles to result in a more efficient charge transfer process. As a result, favorable electrochemical performance was achieved. The performance of the amorphous carbon-graphene co-modified LiFePO4 was further progressively improved upon cycling in the first 200 cycles to reach a reversible specific capacity as high as 97 mAh·g-1 at 10 C rate.

关键词: cathode material, lithium iron phosphate, graphene, amorphous carbon, polyol process

Abstract: Amorphous carbon and graphene co-modified LiFePO4 nanocomposite has been synthesized via a facile polyol process in connection with a following thermal treatment. Various characterization techniques, including XRD, Mössbauer spectra, Raman spectra, SEM, TEM, BET, O2-TPO, galvano charge-discharge, CV and EIS were applied to investigate the phase composition, carbon content, morphological structure and electrochemical performance of the synthesized samples. The effect of introducing way of carbon sources on the properties and performance of LiFePO4/C/graphene composite was paid special attention. Under optimized synthetic conditions, highly crystalized olivine-type LiFePO4 was successfully obtained with electron conductive Fe2P and FeP as the main impurity phases. SEM and TEM analyses demonstrated the graphene sheets were randomly distributed inside the sample to create an open structured LiFePO4 with respect to graphene, while the glucose-derived carbon mainly coated over LiFePO4 particles which effectively connected the graphene sheets and LiFePO4 particles to result in a more efficient charge transfer process. As a result, favorable electrochemical performance was achieved. The performance of the amorphous carbon-graphene co-modified LiFePO4 was further progressively improved upon cycling in the first 200 cycles to reach a reversible specific capacity as high as 97 mAh·g-1 at 10 C rate.

Key words: cathode material, lithium iron phosphate, graphene, amorphous carbon, polyol process