CARBON-COATED LITHIUM IRON PHOSPHATE POSITIVE ACTIVE MATERIAL, METHOD FOR PREPARING SAME, POSITIVE ELECTRODE PLATE CONTAINING SAME, AND LITHIUM-ION BATTERY

A positive active material made of carbon-coated lithium iron phosphate includes a lithium iron phosphate substrate, and a carbon coating layer on a surface of the substrate. The lithium iron phosphate substrate has a general structural formula LiFeMPO, where M is at least one selected from Cu, Mn, Cr, Zn, Pb, Ca, Co, Ni, Sr, Nb, or Ti, and 0≤a≤0.01. A carbon coating factor of the carbon-coated lithium iron phosphate, satisfies 0.81≤η≤0.95, where BET1 denotes a specific surface area of mesopore and macropore structures in the carbon-coated lithium iron phosphate, and BET2 denotes a total specific surface area of the carbon-coated lithium iron phosphate.