Doped lithium manganese iron phosphate-carbon composite material and preparation method thereof

The invention relates to a doped lithium manganese iron phosphate-carbon composite material and a preparation method thereof. The method comprises the following steps: (1) preparing pre-doped manganese oxalate; (2) adding an iron source, a lithium source, a phosphorus source, an organic carbon source and the pre-doped manganese oxalate into water, mixing and grinding to obtain precursor slurry; (3) drying and granulating the precursor slurry to obtain precursor powder; (4) sintering the precursor powder in a protective atmosphere to obtain a sintered material; and (5) crushing the sintered material to obtain the doped lithium manganese iron phosphate-carbon composite material. The preparation method disclosed by the invention is simple in process, and the prepared composite material is high in specific capacity, excellent in cycle performance and relatively good in rate capability. 本发明涉及掺杂的磷酸锰铁锂-碳复合材料及其制备方法。所述方法包括如下步骤：(1)制备预掺杂的草酸锰；(2)将铁源、锂源、磷源、有机碳源以及所述预掺杂的草酸锰加入水中，并混合研磨，获得前体浆料；(3)将所述前体浆料干燥造粒，获得前体粉料；(4)将所述前体粉料在