# US 10,308,511 B2 · Process for manufacturing graphite powder for lithium secondary battery negative electrode material

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,308,511 B2
- Document ID: US10308511B2
- Status: Granted
- Kind: B2
- Application number: 14/438,097
- Filed: 2013-07-23
- Published: 2015-09-10
- Granted: 2019-06-04
- Earliest claimed: 2012-10-24
- Assignees: Tokai Carbon Co., Ltd.
- Applicants: Kazuhiro Yamamoto; Mayuri Komoriya; Motohiro Yamaki; Tomohito Fukugawa; Akihiro Kuroyanagi
- Inventors: Kazuhiro Yamamoto; Mayuri Komoriya; Motohiro Yamaki; Tomohito Fukugawa; Akihiro Kuroyanagi
- Web page: https://patentgrep.com/patent/US10308511B2

## CPC

- C01B 32/05: Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
- C01B 32/20: Graphite
- C01B 32/205: Preparation
- C04B 35/522: {Graphite (C04B35/536 takes precedence)}
- C04B 35/532: containing a carbonisable binder
- H01M 4/587: for inserting or intercalating light metals
- H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
- C01P 2004/51: Particles with a specific particle size distribution
- C01P 2006/12: Surface area
- C01P 2006/40: Electric properties
- C04B 2235/422: Carbon
- C04B 2235/424: Carbon black
- C04B 2235/5409: expressed by specific surface values
- C04B 2235/5436: micrometer sized, i.e. from 1 to 100 micron
- C04B 2235/5481: Monomodal
- H01M 10/052: Li-accumulators
- H01M 2004/021: {Physical characteristics, e.g. porosity, surface area}
- H01M 2004/027: {Negative electrodes}
- Y02E 60/10: Energy storage using batteries
- C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C}
- C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

A method for easily producing a graphite powder for use as a lithium secondary battery negative electrode material with small specific surface area while reducing energy consumption, and achieving high graphitization efficiency, includes melt-mixing a coke powder and a carbon precursor binder so that an amount of fixed carbon included in the carbon precursor binder is 5 to 15 parts by mass based on 100 parts by mass of the coke powder, to prepare a mixture, and pressing the mixture to prepare a compact, the coke powder being obtained by heating a green coke powder at 600 to 1450° C. in a non-oxidizing atmosphere, the green coke powder having a cumulative particle size at 50% in a volumetric cumulative particle size distribution of 5 to 50 μm; heating the compact in a non-oxidizing atmosphere to effect carbonization and graphitization to obtain a graphitized compact; and grinding the graphitized compact.

## Claims

### Claim 1

A method for producing a graphite powder for use as a lithium secondary battery negative electrode material, the method comprising:
melt-mixing a coke powder and a carbon precursor binder so that an amount of fixed carbon included in the carbon precursor binder is 5 to 10 parts by mass based on 100 parts by mass of the coke powder, to prepare a mixture, the coke powder being obtained by heating a green coke powder at 600 to 1450° C. in a non-oxidizing atmosphere, the green coke powder having a cumulative particle size at 50% in a volumetric cumulative particle size distribution of 5 to 50 μm;
pressing the mixture by cold isostatic pressing at a pressure of 100-1000 kgf/cm2 to prepare a compact;
heating the compact in a non-oxidizing atmosphere to effect carbonization and graphitization to obtain a graphitized compact; and
grinding the graphitized compact,
wherein a bulk density of the compact obtained by pressing is 1.2 to 1.8 g/cm3, and
wherein the carbon precursor binder comprises:
(1) ethylene heavy-end alone, or
(2) at least one selected from (A) coal tar pitch and petroleum pitch, and (B) at least one selected from the group consisting of anthracene oil, creosote oil, and FCC decant oil.

### Claim 2 (depends on 1)

The method for producing a graphite powder for use as a lithium secondary battery negative electrode material according to claim 1, wherein bulk density of the compact, obtained by pressing is 1.2 to 1.6 g/cm3, and wherein the pressing of the mixture is performed for 10-180 minutes.

### Claim 3 (depends on 2)

The method for producing a graphite powder for use as a lithium secondary battery negative electrode material according to claim 2, the method producing a graphite powder for use as a lithium secondary battery negative electrode material that has a sphericity of 1.0 to 2.0, a cumulative particle size at 50% in a volumetric cumulative particle size distribution of 5 to 50 μm, a ratio “cumulative particle size at 90% in volumetric cumulative particle size distribution/cumulative particle size at 10% in volumetric cumulative particle size distribution” of 2 to 16, and a specific surface area by nitrogen adsorption of 1.0 to 4.0 m2/g.

### Claim 4 (depends on 1)

The method for producing a graphite powder for use as a lithium secondary battery negative electrode material according to claim 1, the method producing a graphite powder for use as a lithium secondary battery negative electrode material that has a sphericity of 1.0 to 2.0, a cumulative particle size at 50% in a volumetric cumulative particle size distribution of 5 to 50 μm, a ratio “cumulative particle size at 90% in volumetric cumulative particle size distribution/cumulative particle size at 10% in volumetric cumulative particle size distribution” of 2 to 16, and a specific surface area by nitrogen adsorption of 1.0 to 4.0 m2/g.