▎ 摘　　要

NOVELTY - The method involves preparing nano lithium iron phosphate primary grain by utilizing coprecipitation process. Graphene is mixed to the dried phosphate primary grain. A secondary milled grain is sintered to iron phosphate of a lithium-ion battery. A lithium salt is provided with a lithium carbonate. Phosphate is provided with phosphoric acid dihydro, lithium phosphate monoammonium and triammonium phosphate. Ethylene glycol is added to a mixed solution after and before adjusting pH to improve reaction temperature of the mixed solution. USE - Positive material lithium iron phosphate preparation method for a lithium-ion battery. ADVANTAGE - The method enables improving material piling density, thus pilling the lithium iron phosphate grain. DESCRIPTION OF DRAWING(S) - The drawing shows a screen shot illustrating a positive material lithium iron phosphate preparation method.