利用聚乙烯醇（PVA）在水和乙醇中溶解度的不同使PVA均匀析出,可同时使PVA和超细导电碳（SP）均匀包覆在水热合成的LiFePO4表面。该方法不仅在LiFePO4颗粒之间形成三维网状碳结构,而且在LiFePO4颗粒表面形成均匀的无定形碳包覆层。碳包覆后的磷酸铁锂0.2 C首次放电容量由120 mAh/g提高到140 mAh/g,5 C放电容量由10 mAh/g提高到100 mAh/g。%PVA and SP are homogeneously coated on the surface of the hydrothermally synthesized LiFePO4 due to the different solubility of PVA in water and alcohol. After calcination at 600 ~C for 5 h in N2, LiFePOJC anode material was obtained. SEM and TEM photos showed that the PVA formed a three - dimensional network structure among the LiFe- PO4 particles and the LiFePO4 particles were homogeneously coated by a layer of amorphous carbon. After carbon coating, the first discharge specific capacity of LiFePO4 at 0.2 C increased from 120 mAh/g to 140 mAh/g, and the specific ca- pacity at 5 C rate increased from 10 mAh/g to 100 mAh/g.
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