A“core-shell”structure of the carbon-coated intercalated graphite anode material was prepared. Natural graphite was initially intercalted using concentrated phosphoric acid and organic amine pyrolytic carbon coated. The crystal structure, surface morphology and electrochemical properties of the modified natural graphite were analyzed and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy (Raman) and constant current charge-discharge instrument. The results showed that the modified natural graphite’s lattice spacing increased and its surface was successfully coated with a layer of amorphous carbon. Its initial charge capacity was 366.42 mA · h/g and its capacity retention was 87.13%after 20 charge-discharge cycles at 1C rate, while under the same conditions, the capacity retention of natural graphite was only 78.13%. The modified method is effective in improving the rate and cycle performance of natural graphite.%天然石墨经过浓H3PO4插层处理、有机胺热解碳包覆后形成具有“核-壳”结构的碳包覆插层石墨负极材料。利用X射线衍射仪、扫描电子显微镜、拉曼光谱仪和恒流充放电仪对改性天然石墨的晶体结构、表面形貌和电化学性能进行了分析和表征。结果表明：改性后的天然石墨晶面间距增大,表面成功地包覆了一层无定型碳；其首次充电比容量为366.42 mA · h/g,在1 C倍率下循环20周后容量保持率为87.13%,而在同样条件下,天然石墨的容量保持率仅为78.13%。该改性方法有效地改善了天然石墨的倍率性能和循环性能。
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