Carbon-coated and Na <+>-doped LiMnPO4 positive electrode material as well as preparation method and application thereof

The invention relates to a carbon-coated and Na -doped LiMnPO4 positive electrode material as well as a preparation method and application of the carbon-coated and Na -doped LiMnPO4 positive electrode material. The preparation method comprises the following steps of carrying out ball milling on Li2CO3, MnCO3, NH4H2PO4 and sodium polyacrylate, and preparing the sodium-doped LiMnPO4 (at) C material by adopting a high-temperature reduction method, wherein the purposes of coating carbon and doping metal Na < + > can be achieved at the same time by utilizing the sodium polyacrylate. Polypropylene is used as a carbon source, and LiMnPO4/C prepared through high-temperature solid-phase reduction is used as a contrast material. The sodium-doped LiMnPO4 (at) C material has a better olivine structure, a good crystal form and uniform particle size distribution, and the electrochemical properties of the sodium-doped LiMnPO4 (at) C material at all aspects are greatly improved compared with those of LiMnPO4/C which is