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以Fe（NO3）3·9H2O为铁源，LiH2PO4为磷源和锂源，PEG400（平均分子量为400的聚乙二醇）作为碳源和结构调控剂，采用喷雾干燥一高温烧结法合成了球形LiFePO4／C。考察了喷雾干燥过程中，母液浓度、进风温度和进料速率对LiFePO4／c样品形貌、振实密度和电化学性能的影响。结果表明：随母液浓度的降低，样品的粒径变小，粒径分布也更为均匀，但其球形度变差；进风温度过低或过高均会影响样品的粒径分布和颗粒球形度，最佳进风温度为140℃；样品的粒度随进料速率的升高而减小，但过高的进料速率会影响样品的球形度。所制备的LiFePO4／c的振实密度可达1．43g／cm^3，在5C倍率下其放电容量达120．5mAh／g，50次循环后容量几乎没有衰减。“,”Spherical LiFePO4/C cathode materials were successfully prepared by spray drying method combined with high-temperature sintering method using Fe（NO3）3 · 9H2O, LiH2PO4 and PEG400 as iron, lithium, phosphorus and carbon sources. The influences of solution concentration, inlet air temperature and feeding rate on the sample morphology and tap density of LiFePO4/C during the spray drying were studied. Upon reducing the solution concentration, the sphericity was deteriorated, and the particle size decreased while the particle size distribution became narrow. Inlet air temperature has great impact on the sphericity and particle size distribution of particles obtained. The optimized temperature is 140 ℃. The particle size reduced upon increasing the feeding rate. However, over high feeding rate deteriorated the sphericity. The obtained LiFePO4/C particles have a tap density of 1.43 g/cm3 , a discharge capacity of 120.5 mAh/g under 5C. Their capacity almost don＇t decay after 50 cyclings.