采用原位聚合控制结晶法,Fe3+既为沉淀剂又为聚合反应的催化剂,在FePO4核外聚合聚吡咯合成纳米FePO4/PPy前躯体.以FePO4/PPy为铁源,葡萄糖为碳源,高温热处理制备核/壳纳米LiFePO4/C锂离子电池正极材料.并结合X线衍射、扫描电子显微镜、透射电子显微镜、拉曼光谱和充放电测试、循环伏安等手段对合成材料的结构、形貌和电化学性能进行表征.研究结果表明:在FePO4核外聚合PPy能有效抑制LiFePO4颗粒的生长,制得核/壳型纳米LiFePO4/C正极材料；该材料具有良好的电化学性能,在0.1C,0.2C,0.5C和1.0C倍率下的放电比容量分别为149,143,133和129 mA·h/g,且循环性能优异.%FePO4/Ppy nano-precursor was prepared by an in situ polymerization restriction method to form a polypyrrole shell on the surface of FePO4, using Fe3+ as both precipitator and oxidant. LiFePO4/C cathode material for lithium ion battery was synthesized using FePC4/Ppy as ferrous source, and glucose as carbon source. The structure, morphology and electrochemical properties of LiFePO4/C were characterized by X-ray diffraction (XRD), scanning electronic morphology (SEM), transmission electronic morphology (TEM), Raman spectroscopy measurements, galvanostatic charge-discharge tests and cyclic voltammetry(CV). The results show that the polypyrrole shell of FePO4 can effectively restrict the crystallite growth of LiFePO4 particles and obtain core-shell nano-LiFePO4/C cathode material. The electrochemical test results show that the LiFePO4/C cathode material delivers an initial discharge capacity of 149, 143, 133 and 129 mA·h/g at 0.1C, 0.2C, 0.5C and 1.0C, respectively, and has an excellent cycle performance.
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