Electrode Assembly For Secondary Battery And Preparation Method Thereof

Patent metadata

Field	Value
Publication number	US-2024186562-A1
Application number	US-202218277614-A
Country	US
Kind code	A1
Filing date	Aug 12, 2022
Priority date	Aug 13, 2021
Publication date	Jun 6, 2024
Grant date	—

Abstract

The present disclosure relates to a method of preparing an electrode assembly capable of improving life characteristics and rapid charging performance by minimizing a space between a folding separator and an electrode. The method of preparing the electrode assembly includes disposing a plurality of unit cells on a first surface of a folding separator, fixing the unit cells on the first surface of the folding separator, providing a binder composition to at least one end portion of a second surface of the folding separator, and stacking the unit cells by folding the folding separator.

First claim

1 . A method of preparing an electrode assembly, the method comprising:
disposing a plurality of unit cells on a first surface of a folding separator; fixing the unit cells on the first surface of the folding separator; providing a binder composition to at least one end portion of a second surface of the folding separator; and stacking the unit cells by folding the folding separator.

2 . The method of claim 1 , wherein the fixing of the unit cells is performed by heating and pressing the folding separator on which the unit cells are disposed.

3 . The method of claim 1 , wherein the binder composition is provided along a longitudinal direction of the folding separator.

4 . The method of claim 1 , wherein the binder composition is provided at an end portion in a direction in which an electrode tab of the unit cell is disposed.

5 . The method of claim 1 , wherein the providing of the binder composition is performed such that a binder application amount is in a range of 0.1 g/m 2 to 1.0 g/m 2 .

6 . The method of claim 1 , wherein the binder composition is provided in a region at a distance of 0.15 W from an end of the folding separator when a width of the folding separator is W.

7 . The method of claim 1 , wherein the binder composition comprises an aqueous binder.

8 . The method of claim 1 , wherein, after stacking of the unit cells, further comprising heating and pressing the electrode assembly in which the unit cells are stacked.

9 . The method of claim 8 , wherein the heating is performed at a temperature of 50° C. to 150° C., and the pressing is performed under a pressure condition of 10 kPa to 300 kPa.

10 . An electrode assembly comprising:
a plurality of unit cells, wherein each unit cell includes a positive electrode, a separator, and a negative electrode that are stacked by being wound by a long sheet-shaped folding separator, wherein each unit cell includes a sliding portion in which a thickness of an electrode active material layer is reduced at one end of each unit cell, and a binder coating layer formed between the sliding portion and the folding separator.

11 . The electrode assembly of claim 10 , wherein the binder coating layer comprises an aqueous binder.

12 . A secondary battery comprising the electrode assembly of claim 10 .

13 . A secondary battery comprising the electrode assembly of claim 11 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Kim Sung Hwan
• Park Sung Bin
• Lee Seok Kyeong
• Jo Mi Ru
• Cho Woo Hyung

Classifications

• H01M4/621

  Binders · CPC title

• H01M10/0459 Primary

  Cells or batteries with folded separator between plate-like electrodes · CPC title

• H01M10/0468

  Compression means for stacks of electrodes and separators · CPC title

• H01M50/46

  Separators, membranes or diaphragms characterised by their combination with electrodes · CPC title

• H01M10/04 Primary

  Construction or manufacture in general (H01M10/058, H01M10/12, H01M10/28, H01M10/38 take precedence) · CPC title