Electrode structure for secondary battery, method of manufacturing the same, and secondary battery comprising the same

Patent metadata

Field	Value
Publication number	US-2023102903-A1
Application number	US-202217931631-A
Country	US
Kind code	A1
Filing date	Sep 13, 2022
Priority date	Sep 17, 2021
Publication date	Mar 30, 2023
Grant date	—

Abstract

An electrode for a secondary battery includes a current collector; and an active material structure on the current collector, the activate material structure including: at least one first high-density layer, and at least one second high-density layer, the at least one second high-density layer being further away from the current collector as compared to the at least one first high-density layer; and a low-density layer between the at least one first high-density layer and the at least one second high-density layer, wherein a thickness of the at least one second high-density layer is greater than a thickness of the at least one first high-density layer.

First claim

What is claimed is:

1 . An electrode for a secondary battery, the electrode comprising:
a current collector; and an active material structure on the current collector, the active material structure comprising
at least one first high-density layer, and
at least one second high-density layer, the at least one second high-density layer being further away from the current collector as compared to the at least one first high-density layer; and
a low-density layer between the at least one first high-density layer and the at least one second high-density layer, , wherein a thickness of the at least one second high-density layer is greater than a thickness of the at least one first high-density layer.

2 . The electrode of claim 1 , wherein
a solid content of the at least one first high-density layer is about 90 volume percent to about 98 volume percent, based on a total volume of the at least one first high-density layer, a solid content of the at least one second high-density layer is about 90 volume percent to about 98 volume percent, based on a total volume of the at least one second high-density layer, and a solid content of the low-density layer is about 25 volume percent to about 50 volume percent, based on a total volume of the low density layer.

3 . The electrode of claim 1 , wherein an outermost one of the at least one second high-density layer has a greatest thickness among each layer of the at least one first high-density layer, each layer of the at least one second high-density layer, and each layer of the low-density layer.

4 . The electrode of claim 1 , wherein the at least one first high-density layer comprises a primary first high-density layer and a secondary first high-density layer,
the low-density layer comprises a first low-density layer between the primary first high-density layer and the secondary first high-density layer, and the primary first high-density layer and the secondary first high-density layer have a same thickness or a different thickness.

5 . The electrode of claim 4 , wherein a thickness ratio of a thickness of the primary first high-density layer or the secondary first high-density layer to a thickness of each layer of the at least one second high-density layer is greater than about 1:1 and less than or equal to about 1:5.

6 . The electrode of claim 1 , wherein the at least one first high-density layer comprises a primary first high-density layer, a secondary first high-density layer, and a tertiary first high-density layer,
the low-density layer comprises a primary low-density layer between the primary first high-density layer and the secondary first high-density layer, the low-density layer comprises a secondary low-density layer between the secondary first secondary first high-density layer and the tertiary first high-density layer, and at least two of the primary first primary first high-density layer, the secondary first high-density layer, and the tertiary first high-density layer have a same thickness or a different thickness.

7 . The electrode of claim 6 , wherein a thickness ratio of a thickness of the primary first high-density layer, the secondary first high-density layer, or the tertiary first high-density layer to a thickness of each layer of the at least one second high-density layer is greater than about 1:1 and less than or equal to about 1:5.

8 . The electrode of claim 1 , wherein a thickness ratio of a total thickness of the at least one first high-density layer to a total thickness of the at least one second high-density layer is about 1.5:1 to about 1:6.

9 . The electrode of claim 1 , wherein a thickness ratio of a thickness of each first high-density layer of the at least one first high-density layer to a thickness of the low-density layer is about 1:0.1 to about 1:0.3.

10 . The electrode of claim 1 , wherein a thickness ratio of a thickness of each second high-density layer of the at least one second high-density layer to a thickness of each layer of the low-density layer is about 1:0.1 to about 1:0.3.

11 . The electrode of claim 1 , wherein the low-density layer comprises a single layer or a plurality of layers, and
each low-density layer has a thickness of about 2 µm to about 5 µm.

12 . The electrode of claim 1 , wherein the low-density layer comprises at least one of a solid electrolyte, a liquid electrolyte, or an ionic liquid.

13 . The electrode of claim 1 , wherein the at least one first high-density layer and the at least one second high-density layer each independently has a porosity of about 1% to about 5%.

14 . The electrode of claim 1 , wherein the low-density layer has a porosity of about 25 % to about 50%.

15 . The electrode of claim 1 , wherein each layer of the at least one first high-density layer has a thickness of about 8 µm to about 40 µm.

16 . The electrode of claim 1 , wherein each layer of the at least one second high-density layer has a thickness of about 10 µm to about 40 µm.

17 . The electrode of claim 1 , wherein the at least one second high-density layer comprises a primary second high-density layer and a secondary second high-density layer,
the low-density layer is between the primary second high-density layer and the secondary second high-density layer, and the primary second high-density layer and the secondary second high-density layer have a same thickness or different thicknesses.

18 . The electrode of claim 17 , wherein a thickness ratio of a thickness of the primary second high-density layer or the secondary second high-density layer to a thickness of each layer of the low-density layer is about 1:0.1 to about 1:0.3.

19 . The electrode of claim 1 , wherein the at least one second high-density layer comprises a primary second high-density layer, a secondary second high-density layer, and a tertiary second high-density layer,
the low-density layer comprises a first low-density layer between the primary second high-density layer and the secondary second high-density layer, and a second low-density layer between the secondary second high-density layer and the tertiary second high-density layer, and at least two of the primary second primary first high-density layer, the secondary second high-density layer, and the tertiary second high-density layer have a same thickness or different thicknesses.

20 . The electrode of claim 19 , wherein a thickness ratio of a thickness of the primary second high-density layer, the secondary second high-density layer, or the tertiary second high-density layer to a thickness of each layer of the low-density layer is about 1:0.1 to about 1:0.3.

21 . The electrode of claim 1 , wherein the active material structure has a plurality of channels extending in a thickness direction.

22 . The electrode of claim 21 , wherein the plurality of channels comprise at least one of a solid electrolyte, an ionic liquid, or a liquid electrolyte.

23 . The electrode of claim 1 , wherein the electrode is a sintered electrode having a relative density of about 85 % to about 99 %.

24 . The electrode of claim 1 , wherein a thickness ratio of a thickness of each first high-density layer of the at least one first high-density layer to a thickness of each second high-density layer of the at least one second high-density layer is about 1:2 to about 1:4.

25 . The electrode of claim 1 , wherein the active material structure has a plurality of channels extending in

Assignees

• Samsung Electronics Co Ltd

Inventors

• Heo Jinsuck
• Cross Samuel Robert
• Kim Kyounghwan
• Park Joungwon
• Shon Jeongkuk
• Jeong Huisu

Classifications

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/021

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

• H01M2004/027

  Negative electrodes · CPC title