▎ 摘　　要

NOVELTY - Preparing a safe lithium-ion battery comprises (i) preparing LP by a molar ratio of lithium element to phosphorus element of 2:1; preparing FP by a molar ratio of iron element to phosphorus element of 3:1; mixing the LP and FP in a mass ratio of 1:1:1 for lithium element, iron element, and phosphorus element, obtaining a mixture powder of LFP; transferring the LFP mixture powder to a sand mill, grinding to control the D50 of LFP after grinding at 1.5 μm; drying and granulating the ground LFP, transferring to a sintering furnace to obtain lithium iron phosphate; (ii) mixing lithium iron phosphate or graphene with a pore-forming agent, a conductive agent, a binder, and a solvent to prepare a slurry; coating the slurry on a current collector, drying, rolling, and cutting at 46℃, 66℃, 96℃, and 86℃, respectively, to obtain a lithium-ion battery; and (iii) predicting lifespan of lithium-ion battery. USE - Method for preparation of safe lithium ion battery. ADVANTAGE - The lithium ion battery is safe, and has high purity, good conductive heat conductivity, and improved accuracy of the lithium of the service life of the ion battery, and eliminates the influence of the environment to the prediction data. The lithium of ion battery has excellent cycle life test and storage life test.