# US 2015/0147657 A1 · Graphite material for negative electrode of lithium-ion secondary battery, lithium-ion secondary battery including the graphite material, and method of manufacturing graphite material for lithium-ion secondary battery

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- Number: US 2015/0147657 A1
- Document ID: US20150147657A1
- Status: Published application
- Kind: A1
- Application number: 14/411,842
- Filed: 2013-06-25
- Published: 2015-05-28
- Earliest claimed: 2012-06-29
- Assignees: MT Carbon Co., Ltd.
- Applicants: Mt Carbon Co.,Ltd.
- Inventors: Yohei Yagishita; Kohei Yamaguchi; Miwa Katayama; Wataru Oda; Akemi Inami; Yoshiki Kubo; Seiji Okazaki; Akio Sakamoto
- Web page: https://patentgrep.com/patent/US20150147657A1

## CPC

- C01B 32/20: Graphite
- C01B 32/205: Preparation
- H01B 1/04: mainly consisting of carbon-silicon compounds, carbon or silicon
- H01M 4/133: Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
- 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
- H01M 2004/027: {Negative electrodes}
- Y02E 60/10: Energy storage using batteries
- Y02T 10/70: Energy storage systems for electromobility, e.g. batteries
- C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C}
- H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K})
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

## Abstract

A graphite material for a negative electrode of a lithium-ion secondary battery is provided. A ratio Lc(112)/Lc(006) defined as a ratio of expansion of graphene sheets to sheet displacement ranges from 0.08 to 0.11, both inclusive. A crystallite size Lc(006) calculated from a wide-angle X-ray diffraction line ranges from 30 nm to 40 nm, both inclusive. An average particle size ranges from 3 μm to 20 μm, both inclusive.

## Claims

### Claim 1

A graphite material for a negative electrode of a lithium-ion secondary battery, wherein
a ratio Lc(112)/Lc(006) defined as a ratio of expansion of graphene sheets to sheet displacement ranges from 0.08 to 0.11, both inclusive,
a crystallite size Lc(006) calculated from a wide-angle X-ray diffraction line ranges from 30 nm to 40 nm, both inclusive, and
an average particle size ranges from 3 μm to 20 μm, both inclusive.

### Claim 2 (depends on 1)

The graphite material of claim 1, wherein
a total transition metal content ranges from 100 ppm to 2500 ppm, both inclusive.

### Claim 3 (depends on 2)

The graphite material of claim 2, wherein
vanadium of 50 ppm or more is contained.

### Claim 4 (depends on 1)

The graphite material of claim 1, wherein
a ratio Lc(006)/C0(006) indicating the number of lithium insertion sites in a crystallite ranges from 40 to 60, both inclusive.

### Claim 5 (depends on 1)

A lithium-ion secondary battery including the graphite material of claim 1 as a material of a negative electrode.

### Claim 6

A method of manufacturing a graphite material for a negative electrode of a lithium-ion secondary battery, the method comprising:
processing non-needle petroleum coke to have an average particle size ranging from 3 μm to 20 μm, both inclusive by pulverization and classification, the non-needle petroleum coke containing an optically isotropic structure at 75% or higher, transition metals at a total content ranging from 1000 ppm to 2500 ppm, both inclusive, and nitrogen at a content ranging from 1 wt % to 4 wt %, both inclusive; and
graphitizing the processed non-needle petroleum coke at a temperature ranging from 2300° C. to 2900° C., both inclusive.

### Claim 7 (depends on 6)

The method of claim 6, wherein
the non-needle petroleum coke before the processing contains the optically isotropic structure at 85% or higher.

### Claim 8 (depends on 6)

The method of claim 6, wherein
a total content of the transition metal contained in the graphite material formed in the graphitizing ranges from 100 ppm to 2500 ppm, both inclusive.