▎ 摘　　要

NOVELTY - Preparing conductive and ion-conductive double-layer in-situ coated lithium iron phosphate, involves mixing a fast ion conductor coating source compound, a first lithium source compound, a chelating agent and water to form a colloidal solution, wherein the fast ion conductor coating source compound does not contain lithium element. The lithium iron phosphate matrix material is mixed with the colloidal solution, and then carried out a hydrothermal synthesis reaction to obtain a lithium iron phosphate precursor coated by the fast ion conductor. The lithium iron phosphate matrix material comprises a second lithium source compound, a phosphorus source compound and an iron source compound. The coating reaction is carried out on the lithium iron phosphate precursor coated with the fast ion conductor and a carbon source to obtain target product. USE - Method for preparing conductive and ion-conductive double-layer in-situ coated lithium iron phosphate used in lithium-ion battery (claimed). ADVANTAGE - The lithium iron phosphate anode material has a more uniform and compact fast ion conductive layer, where the introduction of the fast ion conducting layer is favorable for greatly improving the ion conductivity of the lithium iron phosphate anode material, and the introduction of the conducting layer is favorable for accelerating the transport rate of electrons. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) A conductive and ion-conductive double-layer in-situ coated lithium iron phosphate, which comprises a lithium iron phosphate core, a fast ion conductor layer and an electronic conductive layer from inside to outside. (2) A lithium-ion battery, which comprises a positive electrode material, that has conductive and ion-conductive double-layer in-situ coated lithium iron phosphate.