▎ 摘　　要

NOVELTY - The material comprises first coating layer coated on base material surface. A second coating layer coated on surface of the first coating layer. The base material comprises binary material or ternary material. The first coating layer comprises lithium manganese iron phosphate. The second coating layer comprises a carbon material. USE - Lithium iron manganese phosphate modified positive electrode material used in lithium ion battery. ADVANTAGE - The manganese phosphate iron lithium and carbon material are synergistic, which effectively improves the lithium ion battery of poor performance in the existing technology, low safety and low safety. DETAILED DESCRIPTION - The material comprises first coating layer coated on base material surface. A second coating layer coated on surface of the first coating layer. The base material comprises binary material of formula LiNi1-cMncO2, or ternary material of formula LiNi1-a-bCoaMnbO2. The first coating layer comprises lithium manganese iron phosphate (LiMnxFe1-xPO4). The second coating layer comprises a carbon material. c=greater than 0.20 to less than 0.40; a=0.0-0.5; b,x=0.05-0.8; and a+b=less than 1. INDEPENDENT CLAIMS are included for: (1) method for preparation of the material comprising (a) under atmosphere of inert gas, mixing the base material, iron salt, manganese salt, lithium salt, phosphate, surface active agent with solvent to obtain suspension, (b) carrying out hydrothermal reaction, and (c) ball milling and calcining the first modified positive electrode material and carbon material to obtain manganese phosphate iron lithium modified positive electrode material; and (2) a lithium ion battery.