# US 12,119,480 B2 · Method for manufacturing secondary battery with improved resistance

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

- Number: US 12,119,480 B2
- Document ID: US12119480B2
- Status: Granted
- Kind: B2
- Application number: 17/296,718
- Filed: 2020-09-16
- Published: 2022-03-17
- Granted: 2024-10-15
- Earliest claimed: 2019-12-09
- Assignees: LG Energy Solution, Ltd.
- Applicants: LG Chem, Ltd.
- Inventors: Ji Hoon Ryu; Song Yi Han
- Web page: https://patentgrep.com/patent/US12119480B2

## CPC

- H01M 4/139: Processes of manufacture
- H01M 50/46: Separators, membranes or diaphragms characterised by their combination with electrodes
- H01M 10/052: Li-accumulators
- H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
- H01M 10/0585: of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
- H01M 10/0567: characterised by the additives
- Y02E 60/10: Energy storage using batteries
- Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product
- Y10T 29/49108: Electric battery cell making
- 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
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

The present invention relates to a method of manufacturing a secondary battery with improved resistance. According to the present invention, since the electrode assembly with succinonitrile interposed at the interface between the electrode and the separator is manufactured and then laminated, a high-pressure process is not required during lamination compared to the prior art, thereby improving processability, and since succinonitrile is dissolved in the electrolyte solution, it exhibits an effect of improving the resistance of the battery.

## Claims

### Claim 1

A method for manufacturing a secondary battery, comprising:
preparing an electrode assembly in which succinonitrile is deposited alone on a separator or an electrode, thereby interposing the succinonitrile at an interface between the electrode and the separator;
laminating by heating and pressing the prepared electrode assembly; and
preparing the secondary battery by accommodating the laminated electrode assembly in a battery case and injecting an electrolyte solution.

### Claim 2 (depends on 1)

The method of claim 1, wherein during the preparing the electrode assembly, the succinonitrile is partially interposed at the interface between the electrode and the separator.

### Claim 3 (depends on 1)

The method of claim 1, wherein during the preparing the electrode assembly, an area to which the succinonitrile is applied is in a range of 1 to 30% of a total area of a portion where the electrode and the separator are laminated.

### Claim 4 (depends on 1)

The method of claim 1, wherein the preparing the electrode assembly includes dropping succinonitrile on a surface of either the electrode or the separator.

### Claim 5 (depends on 4)

The method of claim 4, wherein the preparing the electrode assembly includes:
dropping liquid succinonitrile on one or both sides of the separator;
cooling the succinonitrile to room temperature; and
laminating the electrode on the separator with the succinonitrile interposed therebetween.

### Claim 6 (depends on 4)

The method of claim 4, wherein the preparing the electrode assembly includes:
dropping liquid succinonitrile on one or both sides of the electrode;
cooling the succinonitrile to room temperature; and
laminating the separator on the electrode with the succinonitrile interposed therebetween.

### Claim 7 (depends on 1)

The method of claim 1, wherein the preparing the electrode assembly includes:
applying succinonitrile in a wax phase to a surface of any one of the electrode or the separator.

### Claim 8 (depends on 7)

The method of claim 7, wherein the preparing the electrode assembly includes:
positioning the succinonitrile in a wax phase on one or both sides of the separator;
heating the succinonitrile to a temperature equal to or higher than its melting point and cooling the succinonitrile to a room temperature; and
laminating the electrode on the separator with the succinonitrile interposed therebetween.

### Claim 9 (depends on 7)

The method of claim 7, wherein the preparing the electrode assembly includes:
positioning the succinonitrile in a wax phase on one or both sides of the electrode;
heating the succinonitrile to a temperature equal to or higher than its melting point and cooling the succinonitrile to a room temperature; and
laminating a separator on the electrode with the succinonitrile interposed therebetween.

### Claim 10 (depends on 1)

The method of claim 1, wherein the lamination is performed by pressing the electrode assembly at a temperature of 57° C. or higher.

### Claim 11 (depends on 1)

The method of claim 1, wherein the lamination is performed by pressing the electrode assembly at a pressure of 30 kgf/cm or less.

### Claim 12 (depends on 1)

The method of claim 1, wherein during the injecting the electrolyte solution or after the injecting the electrolyte solution, the succinonitrile is dissolved in the electrolyte solution.