采用XRD测试技术对不同煅烧温度下所得的LiFePO4/C(LFP/C)产物和不同温度氧化处理LFP/C的产物进行了研究，并结合差热分析(DTA)对含碳LFP前驱体和700℃煅烧制备的LFP/C样品的测试结果，研究了LFP/C的制备过程和LFP/C在空气气氛下的氧化过程.实验结果表明，含碳LFP前驱体在350~400℃区间完全分解.当煅烧温度提升至400℃时，含碳LFP前驱体分解产生的FeO、Li4P2O7和H4P2O7反应生成LFP.当煅烧温度升至600℃时可得到无杂相的LFP.进一步提高反应温度有利于LFP结晶度的提高.LFP的最佳煅烧温度应控制在700℃左右.LFP/C样品中的LFP在250~550℃区间被氧化为β-Li3Fe2(PO4)3和α-Fe2O3.LFP/C样品中的碳在750℃时被完全氧化.从提高实验准确度考虑，采用热重法对LFP/C进行碳含量测定时应尽可能将测试温度覆盖到750℃.% LiFePO4/C(LFP/C) samples have been synthesized at different calcination temperatures, and LFP/C oxidation products have also been prepared by oxidizing LFP/C at different temperatures. The oxidation process in atmosphere of LFP/C was analyzed with XRD and differential thermal analysis (DTA) for the carbonaceous LFP precursor and LFP/C samples calcinated at 700℃. The experimental results show that the carbonaceous LFP precursor was decomposed completely in the range of 350–400℃. LFP was produced by FeO, Li4P2O7 and H4P2O7 which were decomposed from the carbonaceous LFP precursor when the calcination temperature increased to 400℃. LFP without impurity phase was obtained when the calcination temperature reached 600℃. Increasing reaction temperature could contribute to improvement of crystallinity of LFP. The optimal calcination temperature of LFPwas around 700℃. LFPin LFP/C sample was oxidized toβ-Li3Fe2(PO4)3 andα-Fe2O3 between 250℃and 550℃. The carbon in LFP/C sample was oxidized completely at 750℃. In consideration of experimental accuracy, the test temperature should be controlled to 750℃as far as possible when testing carbon contentofLFP/Cwiththethermalgravimetricmethod.
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