Method for preparing carbon-coated lithium iron phosphate nanoparticles

The present invention discloses a method of preparing a carbon nanosphere lithium iron phosphate coating, which is deionized water system, a lithium source, a phosphorus source and an iron source to scale preparation, stirred and dissolved in the liquid phase, the organic acid added to adjust the pH to from 1.8 to 5.0, carbon was added, dissolved under stirring, then reacted at high temperature and pressure in the closed vessel, then the carbon-coated lithium iron phosphate obtained nanospheres high temperature sintering. Tested: lithium iron phosphate without Fe2P, Li4P2O7, Fe2O3 and other impurities, and uniform distribution of small particles, is single, D50 between 0.5 and 1.2 microns, and compared with pure crystal, Li Fe bits representing absence disorder bit; its high electronic conductivity, the carbon content of between 1.2% -3.5%, and the tap density of between 0.7-1.0 g / cm3; charge-discharge characteristics, excellent rate characteristics and cycle characteristics, suitable for use as the power type lithium the positive electrode material for batteries.