Patent ID: 9682861
Date: 2017-06-20
CPC Classifications: C01B,H01M,Y02E,Y10T

Claim:
1. A method of synthesizing a lithium metal phosphate composite usable for a lithium secondary battery, comprising the steps of: forming a nanometer-size precursor from a mixture of a first solution having metal ions and a second solution having phosphate ions and a carbon source, wherein the metal of the metal ions is a transitional metal or a combination of transitional metals, and the nanometer-size precursor comprises metal phosphate nanoparticles, each metal phosphate nanoparticle being at least partially covered by a layer of carbon precursor, and wherein the layer of carbon precursor is coated through in situ oxidation polymerization during the formation of the nanometer-size metal phosphate nanoparticles; adding a stoichiometric ratio of a lithium source to the nanometer-size precursor and mixing therewith to form a precursor mixture comprising lithium metal phosphate nanoparticles; spray drying the precursor mixture at a temperature ranged from about 20° C. to about 500° C. to form micron-size particles, wherein the micron-size particles are packed with the lithium metal phosphate nanoparticles; and sintering the micron-size particles at a temperature ranged from about 500° C. to about 1200° C. under an inert and/or reduction atmosphere to form a micron-size spherical lithium metal phosphate composite, wherein the micron-size spherical lithium metal phosphate composite comprises the lithium metal phosphate nanoparticles, each lithium metal phosphate nanoparticle being coated at least partially with a layer of carbon.