▎ 摘　　要

NOVELTY - Preparing modified lithium iron phosphate involves (i) placing the iron source, metal source and phosphorus source according to the proportion of LiM(1-x)FexPO4, 0≤x less than 1 in the dispersant to obtain the precursor; (ii) performing sand grinding treatment and grinding treatment to the precursor till the particle diameter of the precursor is 50-1000 nm, where the particle shape reaches the preset shape; (iii) drying and calcining the precursor under the atmosphere protection to obtain a primary precursor, where the calcining temperature is 300-500℃; (iv) mixing the lithium source according to the proportion in the step (i), placing the lithium source, carbon source and doped metal in the dispersant, performing sand grinding treatment till the particle diameter reaches 100-1000 nm, adding the primary precursor and mixing; and (v) drying the slurry processed in the step (iv) and sintering under the protection of atmosphere, where the sintering temperature is 650-950℃. USE - The method is useful for peparing modified lithium iron phosphate. ADVANTAGE - The method improves the energy density of the lithium iron phosphate, voltage and low temperature performance of ternary material, good multiplying power charging performance, fast charging speed, good low-temperature performance, high energy density, high discharge voltage and good output power, and has low cost, high safety performance, thermal stability, needling, overcharge without spontaneous combustion, long service life, safety and no explosion risk, inhibits the growth of the crystal, reduces the diffusion distance of lithium ion density by nano-crystallization, and increases the conductivity by coating and improves the cycle performance by doping by adding nickel, cobalt, manganese.