中文摘要：

借鉴陶瓷粉体造粒工艺，以聚乙烯醇（PVA）溶液为粘合剂包覆LiFePO4预烧粉体。通过固相热裂解法制备了碳原位包覆的具有微米球形团簇颗粒的LiFePO4／C复合正极粉体材料。复合材料含有单一的磷酸铁锂相。裂解碳以无定型形式存在。造粒工艺显著影响复合材料的微观形貌。在0.1C、0.2C、0.5C和1C的充放电倍率下。研究了碳含量对正极材料的放电比容量和循环稳定性的影响。对于优化样品LFP/C4。具有很高的可逆容量和循环稳定性。在多次循环后材料的放电比容量分别为：149．9,136．9,123．2,108．1mAh·g^-1。特别在高倍率下（1C）。放电容量达到理论容量的63．6％。具有较小的极化效应。容量中点的充放电电位差△V仅为177mV。

英文摘要：

LiFePO4/Carbon composite cathode material with the microstructure of nano-particles aggregated was prepared by granulating and subsequent pyrolysis process with carbon source of polyvinyl alcohol （PVA）. The single LiFePO4 phase and amorphous carbon could be found in the products. The influence of granulating process on the microstructure was significant. A special micro-morphology of optimum sample was observed. The capacity and cycle performance were studied at the charge and discharge rate of 0.1 C,0.2 C,0.5 C and 1 C. The optimum cathode sample （LFP/C4） has high reversible capacity and well cycle stability. Along with the increasing of cycle number, the capacity increases to its saturate value. After several cycles, the capacity is 149.9, 136.9, 123.2, 108.1 mAh·g^-1, respectively. Specially, at high 1 C rate, the cell reaches 63.6% of theory capacity to discharge capacity and has minor polarization effect with only 177 mV of potential difference （△V） of charge-discharge median capacity.