Electrode Assembly

Patent metadata

Field	Value
Publication number	US-2024274861-A1
Application number	US-202218017979-A
Country	US
Kind code	A1
Filing date	Jul 21, 2022
Priority date	Aug 10, 2021
Publication date	Aug 15, 2024
Grant date	—

Abstract

An electrode assembly may have improved rigidity by including a structure in which a negative electrode having separators disposed on both surfaces thereof is bent in a zigzag shape, and a plurality of positive electrodes are individually inserted inside separators bent together with the negative electrode, thereby realizing high safety of the battery. Further, the electrode assembly of the present invention may prevent an end portion of an inserted positive electrode from being exposed by realizing a variation between a separation distance of an end portion of any positive electrode and a separation distance of an end portion of a positive electrode adjacent to the positive electrode with respect to a side surface including the bent structure of the negative electrode at a predetermined ratio, so that the safety and energy density of the battery can be improved.

First claim

1 . An electrode assembly comprising:
a plurality of positive electrode; a negative electrode; and a pair of separators, wherein the plurality of positive electrodes, the negative electrode, and the pair of separators are arranged along a stacking direction to define a stack, wherein the negative electrode has the pair of separators disposed on opposing surfaces of the negative electrode, and the negative electrode and the separators are collectively bent m times (where m is an integer satisfying 2≤m≤100) to follow a serpentine path traversing back and forth across the stack in a lateral dimension transverse to the stacking direction so as to define a plurality of layers, wherein outermost extremities of the negative electrode and the pair of separators in a first direction along the lateral dimension collectively define an outer side of the stack, wherein the plurality of positive electrodes includes n+1 positive electrodes (where n is an integer satisfying 1≤n≤99 and m=n+1) individually positioned between respective layers of the serpentine path defined by the negative electrode and the pair of separators, wherein each of the plurality of positive electrodes has an end portion at an outer edge of the respective positive electrode in the first direction along the lateral dimension, the end portions of the plurality of positive electrodes each being spaced in the lateral dimension from the outer side of the stack by a respective separation distance, and wherein the separation distance of an n th one of the plurality of positive electrodes and the separation distance of an (n+1) th one of the plurality of positive electrodes vary from one another by an amount within a range of 10 μm to 2 mm.

2 . The electrode assembly of claim 1 , wherein the separation distance of the n th one of the plurality of positive electrodes and the separation distance of the (n+1) th one of the plurality of positive electrodes vary from one another by an amount within a range of 10 μm to 500 μm.

3 . The electrode assembly of claim 1 , wherein the separation distance of the n th one of the plurality of positive electrodes and the separation distance of the (n+1) th one of the plurality of positive electrodes vary from one another by an amount within a range of 500 μm to 2,000 μm.

4 . The electrode assembly of claim 1 , wherein the end portions of the positive electrodes adjacent to the outer side of the stack which are not enveloped by a bend of the serpentine path have respective separation distances in a range of 50 μm to 150 μm.

5 . The electrode assembly of claim 1 , wherein the end portions of the positive electrodes adjacent to the outer side of the stack which are not enveloped by a bend of the serpentine path have respective separation distances in a range of 400 μm to 2,000 μm.

6 . The electrode assembly of claim 1 , wherein an average thickness of the negative electrode is in a range of 50 μm to 500 μm.

7 . The electrode assembly of claim 1 , wherein an average thickness of the separator is in a range of 5 μm to 100 μm.

8 . The electrode assembly of claim 1 , wherein an average thickness of the positive electrode is in a range of 50 μm to 500 μm.

9 . The electrode assembly of claim 1 , wherein the negative electrode and the pair of separators are collectively bent 20 times to 60 times in the serpentine path.

10 . A secondary battery comprising:
the electrode assembly of claim 1 ; and a case in which the electrode assembly and an electrolyte are configured to be included.

11 . The secondary battery of claim 10 , comprising:
a positive electrode tab; and a negative electrode tab; wherein the positive electrode tab and the negative electrode tab are connected to one of the positive electrodes and the negative electrode of the electrode assembly, respectively, and the positive electrode tab and the negative electrode tab extend outside to an exterior of the case, wherein the positive electrode tab and the negative electrode tab are located on a side surface of the electrode assembly extending parallel to both the lateral dimension and the stacking direction.

Assignees

• Lg Energy Solution Ltd

Inventors

• Han Hyun Gyu

Classifications

• H01M10/04

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

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• H01M10/0454 Primary

  Cells or batteries with electrodes of only one polarity folded · CPC title

• H01M50/538

  Connection of several leads or tabs of wound or folded electrode stacks · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title