# US 2017/0288231 A1 · Method for manufacturing of slurry for negative electrode

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

- Number: US 2017/0288231 A1
- Document ID: US20170288231A1
- Status: Published application
- Kind: A1
- Application number: 15/470,201
- Filed: 2017-03-27
- Published: 2017-10-05
- Earliest claimed: 2016-03-29
- Assignees: LG Chem, Ltd.
- Applicants: LG Chem, Ltd.
- Inventors: Ji Hee Yoon; Jun Soo Park; Je Young Kim; Jung Woo Yoo
- Web page: https://patentgrep.com/patent/US20170288231A1

## CPC

- H01M 4/622: {being polymers}
- H01M 4/0404: {by coating on electrode collectors}
- H01M 4/133: Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
- H01M 4/134: Electrodes based on metals, Si or alloys
- H01M 4/1393: of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
- H01M 4/1395: of electrodes based on metals, Si or alloys
- H01M 4/364: {as mixtures}
- H01M 4/386: {Silicon or alloys based on silicon}
- H01M 4/483: {for non-aqueous cells (H01M4/485 takes precedence)}
- H01M 4/587: for inserting or intercalating light metals
- H01M 4/0435: {Rolling or calendering}
- 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}
- H01M 2220/20: Batteries in motive systems, e.g. vehicle, ship, plane
- H01M 2220/30: Batteries in portable systems, e.g. mobile phone, laptop
- Y02E 60/10: Energy storage using batteries
- 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

## Abstract

The present invention relates to a method of preparing a negative electrode slurry, and, specifically, the present invention provides a method of preparing a negative electrode slurry which includes the steps of preparing a first negative electrode slurry including a silicon-based active material, a carboxymethyl cellulose, and a styrene-butadiene rubber, and a second negative electrode slurry including a graphite-based active material, a conductive agent, a styrene-butadiene rubber, and a carboxymethyl cellulose (step 1), and mixing the first negative electrode slurry and the second negative electrode slurry which are prepared in step 1 (step 2).

## Claims

### Claim 1

A method of preparing a negative electrode slurry, the method comprising steps of:
preparing a first negative electrode slurry including a silicon-based active material, a carboxymethyl cellulose, and a styrene-butadiene rubber, and a second negative electrode slurry including a graphite-based active material, a conductive agent, a styrene-butadiene rubber, and a carboxymethyl cellulose (step 1); and
mixing the first negative electrode slurry and the second negative electrode slurry which are prepared in step 1 (step 2).

### Claim 2 (depends on 1)

The method of claim 1, wherein a weight ratio of the carboxymethyl cellulose in the first negative electrode slurry to the carboxymethyl cellulose in the second negative electrode slurry is in a range of 0.5:9.5 to 5:5.

### Claim 3 (depends on 1)

The method of claim 1, wherein a weight ratio of the silicon-based active material to the graphite-based active material is in a range of 1:9 to 3:7.

### Claim 4 (depends on 1)

The method of claim 1, wherein the preparing of the first negative electrode slurry comprises steps of:
preparing a first mixed solution by mixing the carboxymethyl cellulose and the styrene-butadiene rubber with a solvent (step 1a); and
mixing the first mixed solution with the silicon-based active material to prepare the first negative electrode slurry (step 1b).

### Claim 5 (depends on 1)

The method of claim 1, wherein the preparing of the second negative electrode slurry comprises steps of:
preparing a second mixed solution by mixing the carboxymethyl cellulose and the conductive agent with a solvent (step 1c);
mixing the second mixed solution with the graphite-based active material (step 1d); and
mixing the styrene-butadiene rubber with the second mixed solution in which the graphite-based active material is mixed (step 1e).

### Claim 6 (depends on 1)

The method of claim 1, wherein a weight ratio of the silicon-based active material:the carboxymethyl cellulose:the styrene-butadiene rubber in the first negative electrode slurry is in a range of 94:3.0:3.0 to 99:0.5:0.5.

### Claim 7 (depends on 1)

The method of claim 1, wherein a weight ratio of the graphite-based active material the carboxymethyl cellulose:the styrene-butadiene rubber:the conductive agent in the second negative electrode slurry is in a range of 91:3.0:3.0:3.0 to 98.5:0.5:0.5:0.5.

### Claim 8 (depends on 1)

The method of claim 1, wherein the silicon-based active material is SiO.

### Claim 9 (depends on 1)

The method of claim 1, wherein the graphite-based active material comprises artificial graphite and natural graphite.

### Claim 10 (depends on 1)

A negative electrode slurry prepared by the method of preparing a negative electrode slurry of claim 1.

### Claim 11 (depends on 10)

A method of preparing a negative electrode, the method comprising steps of:
coating a current collector with the negative electrode slurry of claim 10 (step 3); and
drying and rolling the negative electrode slurry coated on the current collector of step 3 (step 4).

### Claim 12 (depends on 11)

A negative electrode prepared by the method of preparing a negative electrode of claim 11.