▎ 摘　　要

NOVELTY - Preparation of phosphate-and nitrogen-doped graphene-modified lithium iron phosphate involves mixing 5-10 mol/L iron source solution, adding concentrated sulfuric acid and hydrogen peroxide, oxidizing, where mass ratio of iron source, concentrated sulfuric acid, and hydrogen peroxide solution is 100:15-25:2-5, adding 5-10 mol/L phosphate solution, washing by water, mixing, stirring, adding phosphoric acid, precipitating, filtering, washing, drying, and grinding; and adding carbon source, lithium source, and graphene oxide, and ball milling. USE - Method for preparing phosphate-and nitrogen-doped graphene-modified lithium iron phosphate (claimed) used for battery. ADVANTAGE - The modified lithium iron phosphate provides excellent static performance, greatly reduces contact resistance of anode material, has improved adhesion ability, reduces the use quantity of binder, and improves battery performance. DETAILED DESCRIPTION - Preparation of phosphate-and nitrogen-doped graphene-modified lithium iron phosphate comprises: (A) mixing 5-10 mol/L iron source solution, adding concentrated sulfuric acid and hydrogen peroxide, oxidizing, where mass ratio of iron source, concentrated sulfuric acid, and hydrogen peroxide solution is 100:15-25:2-5, adding 5-10 mol/L phosphate solution, washing by water, mixing, stirring, adding phosphoric acid, precipitating, filtering, washing, drying, and grinding; (B) adding carbon source, lithium source, and graphene oxide, and ball milling, where ratio of iron phosphate, lithium source, carbon source, and graphene oxide is 0.95-1.05:1:0.1-0.5:0.01-0.05; dispersing pyrrole monomer in deionized water, stirring to get 1-5 mol/L pyrrole monomer, adding product in second step, and fully stirring, where ratio of pyrrole monomer solution to product in first step is 10-20:100; and (C) dissolving oxidant in deionized water, stirring, slowly adding product in third step at ratio of 10-20:100, oxidative polymerizing, spray drying, pelletizing, and calcining for 8-24 hours at 650-800 degrees C under inert gas protection.