Patent ID: 9296612
Filing Date: 2016-03-29
CPC Classification: C01B

Claim Text:
1. A method of synthesizing a phosphorous active electrode composite material AMPO 4 , wherein M is a first element, and A is a second element, the method comprising: (a) preparing a first source material comprising the first element M and a phosphorus source material, wherein the first element M in the first source material and the phosphorus in the phosphorus source material has a predetermined molar ratio; (b) forming a phosphoric acid aqueous solution with the phosphorus source material, and adding the first source material in the phosphoric acid aqueous solution to form a first mixture; (c) drop-wisely adding a hydrogen peroxide aqueous solution in the first mixture with stirring to form a second mixture, wherein the second mixture comprises a phosphate composite comprising the first element M; (d) measuring amounts of the first element M and phosphorus (P) in the second mixture, and mixing the phosphate composite in the second mixture with a second source material comprising the second element A to form an intermediate mixture, wherein the intermediate mixture is formed with A:M:P=1.03-1.1:1:1 by molar ratio; (e) adding a carbon precursor to the intermediate mixture, wherein the carbon precursor is about 5-30% by weight to the intermediate mixture; (f) ball-milling and drying the intermediate mixture; and (g) sintering the intermediate mixture in an inert environment at about 250-900° C. for about 6 to 15 hours to form the phosphorous composite active electrode material, wherein the first element M is selected from a group consisting of iron (Fe), manganese (Mn), and a mixture thereof; and wherein the second element A is selected from a group consisting of lithium (Li), sodium (Na), potassium (K) and a mixture thereof.