METHOD FOR PREPARING GRAPHENE-BASED LiFePO4/C COMPOSITE MATERIAL

A method for preparing a graphene-based LiFePO4/C composite material, comprising:

• dissolving a graphene oxide and an iron salt in a deionized water, a mass ratio of the graphene oxide over an iron element in the iron salt being 0.1˜0.3:1;
• dispersing the graphene oxide by ultrasonic to obtain an iron salt solution having the graphene oxide dispersed therein;
• mixing the iron salt solution with a phosphate solution to obtain a reaction mixture, in which a molar ratio of Fe:P 1:1˜1.2;
• adjusting a pH value of the reaction mixture to 2 to 4;
• controlling a temperature of the reaction mixture to allow the reaction mixture to react at 60° C. to 80° C. to obtain an emulsion;
• filtering the emulsion to obtain a ferric phosphate/graphene oxide precursor;
• blending the ferric phosphate/graphene oxide precursor with a lithium salt at a Li:Fe molar ratio of 1˜1.05:1 to form a first mixture;
• adding a carbon source to the first mixture to form a second mixture;
• and
• sintering the second mixture under a reducing atmosphere condition at 600° C. to 700° C., to obtain the graphene-based LiFePO4/C composite material.