Patent ID: 11949087
Assignee: BEIJING TUNGHSU CARBON ADVANCED MATERIALS TECHNOLOGY CO., LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A method for preparing a graphene-coated powder material, comprising the steps of:
A) providing a first organic solvent dispersion of a graphene powder and/or graphene oxide powder, a powder material to be coated with graphene, and a polymeric co-coating agent dispersed in a first organic solvent;
B) mixing the first organic solvent dispersion with a second organic solvent and separating a precipitate; and
C) annealing the precipitate in an inert atmosphere to obtain the graphene-coated powder material;
wherein the polymeric co-coating agent is soluble in the first organic solvent but insoluble in the second organic solvent; and
wherein the annealing comprises the steps of:
1) Raising the temperature from room temperature to an intermediate temperature of 300-500° C. at a ramping rate of 1-3° C./min, and then holding for 1-2 hours; and
2) further raising the temperature to a maximum temperature of 500-800° C. at a ramping rate of 3-6° C./min, and then holding for 2-3 hours;

wherein Y≥2X≥2, and 300≤A<B≤800; and
wherein the powder material is a lithium ion battery cathode material, and the lithium ion battery cathode material is one or more selected from the group consisting of lithium manganate, lithium cobaltate, and a ternary material selected from the group consisting of nickel-cobalt-manganese ternary materials, nickel-cobalt-aluminum ternary materials, and lithium-rich ternary materials.