CARBON MATERIAL FOR NEGATIVE ELECTRODE FOR LITHIUM ION SECONDARY BATTERY, MANUFACTURING PROCESS THEREFOR AND USE THEREOF

• US 20180226649A1
• Filed: 04/04/2018
• Published: 08/09/2018
• Est. Priority Date: 09/27/2012
• Status: Abandoned Application

• Current Assignee: Showa Denko KK
• Original Assignee: Showa Denko KK
• Inventors: WAKIZAKA, Yasuaki, SOTOWA, Chiaki, TERASHIMA, Takashi
• Application Number:
  US15/945,066
• Publication Number:
  US 20180226649A1
• Time in Patent Office: Days
• CPC Class Codes: B29C 43/003 characterised by the choice of material
• CPC Class Codes: B29L 2031/3468 Batteries, accumulators or fuel cells battery cases B29L2031/7146
• CPC Class Codes: C01B 32/20 Graphite
• CPC Class Codes: C01B 32/205 Preparation
• CPC Class Codes: C01B 32/21 After-treatment
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 2004/027 Negative electrodes
• CPC Class Codes: H01M 4/133 Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A carbon material for negative electrodes in lithium ion secondary battery, wherein a specific surface area is not less than 1.5 m²/g and not more than 6.5 m²/g, a tap density is not less than 0.5 g/cm³ and not more than 1.3 g/cm³, a Raman R value is not less than 0.1 and not more than 0.4, no diffraction peak is present in a range of diffraction angle of 42.7° to 43.7° in X-ray diffraction analysis, d₀₀₂ is not more than 0.337 nm, and at most one peak is present in a range of not less than 500° C. and less than 1000° C. in thermogravimetric-differential thermal analysis.

Claims

1. A method for manufacturing a carbon material for use in negative electrode of lithium ion secondary battery, comprising

applying impact compression force to a granular artificial graphite made from needle coke using a mechanical rotary machine under conditions of a peripheral velocity of not less than 20 m/s and not more than 200 m/s and a processing duration of not less than 10 seconds and not more than 5 minutes to perform surface modification.

2. The method according to claim 1, wherein the granular artificial graphite has a 50% particle diameter of not less than 1 μ

m and not more than 50 μ

m in volumetric basis cumulative particle size distribution as measured by laser diffractometry.

3. The method according to claim 2, wherein the surface modification is performed at a ratio of an apparent density after performing the surface modification to an apparent density before performing the surface modification is less than 1.1, and a ratio of a 50% particle diameter after performing the surface modification to the 50% particle diameter before performing the surface modification is not less than 0.9 and less than 1.1 in volumetric basis cumulative particle size distribution as measured by laser diffractometry.

4. The method according to claim 3, wherein a throughput per batch in the surface modification is not less than 1 kg and not more than 100 kg.

5. The method according to claim 1, wherein the granular artificial graphite is an artificial graphite synthesized by heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C.

6. The method according to claim 1, wherein the granular artificial graphite is an artificial graphite synthesized by subjecting a carbonized material to heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C., and the carbonized material is obtained by heat treatment at a temperature of not less than 1000°

C. and not more than 2000°

C.

7. The method according to claim 1, wherein the granular artificial graphite is an artificial graphite synthesized by subjecting a particulate material to heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C., the particulate material is obtained by pulverization and classification of a carbonized material, and the carbonized material is obtained by heat treatment at a temperature of not less than 1000°

C. and not more than 2000°

C.

8. The method according to claim 2, wherein the granular artificial graphite is an artificial graphite synthesized by heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C.

9. The method according to claim 2, wherein the granular artificial graphite is an artificial graphite synthesized by subjecting a carbonized material to heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C., and the carbonized material is obtained by heat treatment at a temperature of not less than 1000°

C. and not more than 2000°

C.

10. The method according to claim 2, wherein the granular artificial graphite is an artificial graphite synthesized by subjecting a particulate material to heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C., the particulate material is obtained by pulverization and classification of a carbonized material, and the carbonized material is obtained by heat treatment at a temperature of not less than 1000°

C. and not more than 2000°

C.

11. The method according to claim 3, wherein the granular artificial graphite is an artificial graphite synthesized by heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C.

12. The method according to claim 3, wherein the granular artificial graphite is an artificial graphite synthesized by subjecting a carbonized material to heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C., and the carbonized material is obtained by heat treatment at a temperature of not less than 1000°

C. and not more than 2000°

C.

13. The method according to claim 3, wherein the granular artificial graphite is an artificial graphite synthesized by subjecting a particulate material to heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C., the particulate material is obtained by pulverization and classification of a carbonized material, and the carbonized material is obtained by heat treatment at a temperature of not less than 1000°

C. and not more than 2000°

C.

14. The method according to claim 4, wherein the granular artificial graphite is an artificial graphite synthesized by heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C.

15. The method according to claim 4, wherein the granular artificial graphite is an artificial graphite synthesized by subjecting a carbonized material to heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C., and the carbonized material is obtained by heat treatment at a temperature of not less than 1000°

C. and not more than 2000°

C.

16. The method according to claim 4, wherein the granular artificial graphite is an artificial graphite synthesized by subjecting a particulate material to heat treatment at a temperature of not less than 2400°

C. and not more than 3600°

C., the particulate material is obtained by pulverization and classification of a carbonized material, and the carbonized material is obtained by heat treatment at a temperature of not less than 1000°

C. and not more than 2000°

C.