A Facile Approach to Prepare LiFePO₄/C Composite with High-Rate Performance

Authors

Peng ZHANG, State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050;
Ling-Bin KONG, School of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, Gansu China
Yong-Chun LUO, School of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, Gansu China
Long KANG, School of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, Gansu China

Corresponding Author

Ling-Bin KONG(konglb@lut.cn)

Abstract

The LiFePO₄/C composite electrode material was synthesized by a moderate in situ carbothermal reduction method at 600 °C using FeCl₃.6H₂O, LiOH.H₂O, and NH₄H₂PO₄ as starting materials, soluble starch sol as a carbon source and a reducing agent. This method is readily reproducible and possibly feasible to carry out large-scale synthesis. The structure and morphology of the LiFePO₄/C samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The synthesized LiFePO₄/C composite was in pure phase of olivine-type, shows highly crystalline and spherical morphology with the particle sizes in the range of 60 ~ 100 nm. The thickness of the carbon film could be as thin as about 2 nm for the isolated LiFePO₄/C particles, and the amount of carbon introduced into the composite was about 5% (by mass). The measured tap density of LiFePO₄/C composite was as high as 1.3 g.cm^-3 and the initial discharge capacities of LiFePO₄/C composite reached 162, 143, 135, 127, 116 and 105 mAh?g-1 at 0.2C, 0.5C, 1C, 2C, 5C and 10C rates, respectively. Remarkably, even after 500 cycles at 10C, the capacity of 81 mAh.g^-1 could be obtained.

Graphical Abstract

Keywords

Li ion battery, cathode materials, LiFePO4/C, core-shell structure

DOI Link

https://doi.org/10.61558/2993-074X.2928

Publication Date

2012-08-28

Online Available Date

2012-03-03

Revised Date

2012-02-27

Received Date

2011-11-24

Recommended Citation

Peng ZHANG, Ling-Bin KONG, Yong-Chun LUO, Long KANG. A Facile Approach to Prepare LiFePO₄/C Composite with High-Rate Performance[J]. Journal of Electrochemistry, 2012 , 18(4): Article 11.
DOI: 10.61558/2993-074X.2928
Available at: https://jelectrochem.xmu.edu.cn/journal/vol18/iss4/11

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