Cathode material LiMn1-xFexPO4 for lithium ion cell and preparation method of cathode material LiMn1-xFexPO4

The invention discloses a cathode material LiMn1-xFexPO4 for a lithium ion cell and a preparation method of the cathode material LiMn1-xFexPO4. The preparation method comprises the following steps: manganese source compounds and iron source compounds are adopted as the raw materials to prepare manganese-rich solution and a manganese-poor solution respectively, a FeMnPO4 precursor with a gradient structure is synthesized through a coprecipitation method by controlling the sample adding speed, and then lithium doping and high-temperature calcination are performed to prepare the LiMn1-xFexPO4 with a gradient structure, that is the manganese content of the LiMn1-xFexPO4 is gradually reduced while the iron content of the LiMn1-xFexPO4 is gradually increased from inside to outside along the particle radius of the LiMn1-xFexPO4. The anode material LiMn1-xFexPO4 with the gradient structure has the characteristics of high energy density, good cycle performance and excellent rate capability and is applied to the field of application of power lithium-ion batteries.