Porous graphene for cathode of secondary battery and its manufacturing method

Patent metadata

Field	Value
Publication number	US-2016285095-A1
Application number	US-201414778390-A
Country	US
Kind code	A1
Filing date	Mar 12, 2014
Priority date	Mar 19, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

In the graphene manufacturing method, a graphite oxide is formed from graphite, and then the graphite oxide is treated with a hydrochloric acid. The hydrochloric acid-treated graphite oxide is reduced at temperature of 120° C. or above and 200° C. or below by performing thermal treatment thereto. Since a low-temperature process is used for manufacturing graphene by performing thermal treatment at a relatively low temperature for a short time, this method has great economic feasibility and utilization. Due to a simple composing process and low thermal treatment temperature, graphene may be mass-produced with a low price. In particular, the graphene may be used as a cathode material for a lithium secondary battery, which exhibits a high capacity at a high voltage of 2V or above by reacting with Li, different from an anode material of a lithium secondary battery.

First claim

What is claimed is:

1 . A graphene manufacturing method, comprising:
forming a graphite oxide from graphite; treating the graphite oxide with a hydrochloric acid; and performing thermal treatment to the hydrochloric acid-treated graphite oxide at temperature of 120° C. to 200° C. to be reduced.

2 . The graphene manufacturing method according to claim 1 ,
wherein in the step of forming a graphite oxide, an oxidizer is used for oxidizing the graphite, and the degree of functionalization of graphene is controlled by adjusting the amount of the oxidizer.

3 . The graphene manufacturing method according to claim 1 ,
wherein the thermal treatment is performed under an air or inert gas atmosphere.

4 . The graphene manufacturing method according to claim 1 ,
wherein in addition to the thermal treatment, thermal treatment for reduction is further performed at 200° C. or above under an inert gas atmosphere.

5 . The graphene manufacturing method according to claim 3 ,
wherein the inert gas is at least one selected from the group consisting of helium (He), nitrogen (N 2 ), argon (Ar), neon (Ne) and xenon (Xe).

6 . A porous graphene for a cathode of a secondary battery, which is prepared by the graphene manufacturing method according to claim 1 .

7 . The porous graphene for a cathode of a secondary battery according to claim 6 ,
wherein the porous graphene exhibits a high voltage of 2V in comparison to lithium.

8 . The porous graphene for a cathode of a secondary battery according to claim 6 ,
wherein the porous graphene has a microstructure composed of graphene nano-plates with a thickness of 10 nm and has a pore size of several ten to several hundred nm, and the pore is formed to extend from an inside of the graphene nano-plates to a surface thereof.

9 . A secondary battery, comprising:
a cathode prepared by coating slurry for an electrode, which includes the graphene manufactured by the method according to claim 1 ; an anode containing metal; a separator; and an electrolyte containing ions of the metal.

10 . The secondary battery according to claim 9 ,
wherein the metal is lithium or sodium.

11 . The graphene manufacturing method according to claim 4 ,
wherein the inert gas is at least one selected from the group consisting of helium (He), nitrogen (N 2 ), argon (Ar), neon (Ne) and xenon (Xe).

Assignees

• Snu R&Db Foundation

Inventors

• Kang Ki-Suk
• Kim Hae-Gyeom

Classifications

• C01B2204/04

  Specific amount of layers or specific thickness · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• H01M4/587 Primary

  for inserting or intercalating light metals · CPC title

• C01B31/0446

  Chemistry & Metallurgy · mapped topic