Electrode active material, method for manufacturing same, and lithium secondary battery comprising same

Patent metadata

Field	Value
Publication number	US-11440802-B2
Application number	US-201716613795-A
Country	US
Kind code	B2
Filing date	May 18, 2017
Priority date	May 17, 2017
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

The present invention relates to an electrode active material, a method for manufacturing the same, and a lithium secondary battery comprising the same. A method for producing carbide using bean curd or waste bean curd according to an embodiment of the present invention comprises the steps of: drying bean curd or waste bean curd; thermally treating the dried bean curd or waste bean curd under an air atmosphere; and carbonizing the thermally treated bean curd or waste bean curd under an inert gas atmosphere.

First claim

The invention claimed is:

1. A method for manufacturing a carbide using bean curd (tofu) or waste bean curd (tofu), the method comprising:
drying bean curd (tofu) or waste bean curd (tofu);
thermally treating the dried bean curd (tofu) or waste bean curd (tofu) under an air atmosphere; and
carbonizing the thermally treated bean curd (tofu) or waste bean curd (tofu) under an inert gas atmosphere.

2. The method of claim 1 , wherein a drying process is performed at a temperature of 40° C. to 200° C. for 24 hours to 100 hours.

3. The method of claim 1 , wherein a drying process is performed in at least any one dryer selected from the group consisting of a hot air dryer, a flash dryer, a cake dryer, and a ring dryer.

4. The method of claim 1 , wherein a thermal treatment process is performed at a temperature of 200° C. to 500° C. for 30 minutes to 10 hours.

5. The method of claim 1 , wherein a carbonization process is performed at a temperature of 500° C. to 900° C. for 30 minutes to 3 hours.

6. The method of claim 1 , wherein the method further comprises crystallizing a carbonized bean curd (tofu) or waste bean curd (tofu) under an inert gas atmosphere after the performing of a carbonization process.

7. The method of claim 6 , wherein a crystallization process is performed at a temperature of 1,000° C. to 1,500° C. for 30 minutes to 3 hours.

8. The method of claim 6 , wherein the method further comprises pulverizing a crystallized carbide after the performing of a crystallization process.

9. The method of claim 8 , wherein a pulverization process is performed by at least one pulverizer selected from the group consisting of a pin mill, a fine impact mill, a ball mill, beads mill, a rotor-mounted airflow type classifier, Dyno mill, a disc mill, a roll mill, and a cyclone.

10. The method of claim 1 , wherein the inert gas includes at least any one selected from the group consisting of nitrogen (N 2 ), argon (Ar), helium (He), neon (Ne), krypton (Kr), and xenon (Xe).

11. A carbide being manufactured by the method of claim 1 , having an average interlayer spacing (d002) of a (002) plane of 3.7 Å to 4.0 Å, which is obtained by an X-ray diffraction method, a crystallite diameter Lc (002) in the C-axis direction of 0.8 nm to 2 nm, an R value of 1.3 to 2, and a peak intensity ratio (5° angle peak/002 peak) of 2° to 4° of an angle.

12. The carbide of claim 11 , wherein the carbide has an average particle size D50 of 10 nm to 50 μm.

13. The carbide of claim 11 , wherein the carbide has a specific surface area of 50 m 2 /g to 500 m 2 /g and an average pore size of 1 nm to 2 nm.

14. A lithium secondary battery comprising an anode active material including the carbide of claim 11 , wherein the lithium secondary battery has an irreversible capacity of 200 mAh/g to 600 mAh/g and a capacity retention rate at 50 cycles of 90% or more.

Assignees

• Found Res & Business Seoul Nat Univ Sci & Tech

Inventors

• Ahn Hyo Jin
• Lee Do Young
• An Geon Hyoung

Classifications

• C01B32/05

  Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30 · CPC title

• C01P2006/12

  Surface area · CPC title

• B01D2009/0086

  Processes or apparatus therefor · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M10/0525

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