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Corresponding Author

Ning-yu GU(nygu@ncu.edu.cn)

Abstract

The LiFePO4/C samples have been synthesized via an aqueous solution-evaporation route with LiH2PO4, FeC2O4.2H2O as raw materials and citric acid as a carbon source. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to analyze structure and morphology of the samples. The electrochemical performances of the LiFePO4/C cathodes were characterized by charge/discharge cures and electrochemical impedance spectroscopy (EIS). The results show that the LiFePO4/C sample, calcined at 700 °C and contained 3.03% (by mass) carbon, exhibited a highly pure crystalline phase with the primary particles sizes of 100 nm. The surfaces of those particles were covered by a carbon layer of 5 nm in thickness. At the rates of 0.5C, 2C, 5C, and 10C, where 1C corresponds to 170 mA.g-1, the discharge capacities of 148.2, 142.7, 127.4, and 108.5 mAh.g-1, were delivered, respectively, with the perfect cycling stabilities.

Graphical Abstract

Keywords

lithium-ion batteries, cathode material, LiFePO4/C, citric acid

Publication Date

2013-04-28

Online Available Date

2012-03-29

Revised Date

2012-03-19

Received Date

2012-02-17

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