Cathode for metal-air battery including spaces for accommodating metal oxides formed during discharge of metal-air battery and metal-air battery including the same

Patent metadata

Field	Value
Publication number	US-11670753-B2
Application number	US-202017120684-A
Country	US
Kind code	B2
Filing date	Dec 14, 2020
Priority date	Nov 1, 2016
Publication date	Jun 6, 2023
Grant date	Jun 6, 2023

Abstract

Provided is a metal-air battery including a cathode having a space which may be filled with a metal oxide formed during a discharge of the metal-air battery and thus having improved energy density and lifespan. The cathode for the metal-air battery includes a plurality of cathode materials, a plurality of electrolyte films disposed on surfaces of the plurality of cathode materials, and a plurality of spaces which are not occupied by the plurality of cathode materials and the plurality of electrolyte films. A volume of the plurality of spaces may be greater than or equal to a maximum space of a metal oxide formed during a discharge of the metal-air battery.

First claim

What is claimed is:

1. A cathode for a metal-air battery, the cathode comprising:
a cathode layer comprising a cathode material including at least one selected from carbon black, graphite, graphene, activated carbon, carbon fiber and carbon nanotubes;
a plurality of holes vertically defined through the cathode layer; and
a plurality of electrolyte films disposed on inner walls of the cathode layer, which define the plurality of holes,
wherein a plurality of spaces, which are not occupied by the plurality of electrolyte films and surrounded by the plurality of electrolyte films, are defined in the plurality of holes, and
wherein the plurality of holes is spaced apart from each other by a predetermined distance.

2. The cathode of claim 1 , wherein each of the plurality of electrolyte films on the inner walls of the cathode layer has a thickness of about 10 nm or less.

3. The cathode of claim 1 , wherein the plurality of holes are arranged in the cathode layer at a density greater than about 10 9 /cm 2 .

4. The cathode of claim 1 , wherein a volume of each of the plurality of spaces is equal to or less than 120% of a predetermined volume.

5. The cathode of claim 1 , wherein each of the plurality of holes has a polygonal or round shape.

6. The cathode of claim 1 , wherein the plurality of holes are regularly arranged.

7. A metal-air battery comprising:
a cathode comprising a cathode layer including at least one selected from carbon black, graphite, graphene, activated carbon, carbon fiber and carbon nanotubes, a plurality of holes vertically defined through the cathode layer from a top surface of the cathode layer to a bottom surface of the cathode layer, and a plurality of electrolyte films disposed on inner walls of the cathode layer, which define the plurality of holes;
an anode metal layer facing the bottom surface of the cathode layer; and
a gas diffusion layer which supplies oxygen to the cathode layer and faces the top surface of the cathode layer,
wherein a plurality of spaces, which are not occupied by the plurality of electrolyte films and surrounded by the plurality of electrolyte films, are defined in the plurality of holes,
wherein the plurality of holes is spaced apart from each other by a predetermined distance,
wherein a volume of each of the plurality of spaces is greater than or equal to a maximum volume of a product formed between each of the plurality of electrolyte films and the inner wall in a corresponding one of the plurality of holes during a discharge of the metal-air battery, and
wherein each of the plurality of spaces is surrounded by one of the plurality of electrolyte films.

8. The metal-air battery of claim 7 , wherein an area of a cross-section of each of the plurality of spaces when the product is not formed is greater than an area of a cross-section of the product on the inner wall in each of the plurality of holes when the product is formed.

9. The metal-air battery of claim 7 , wherein the plurality of holes are arranged in the cathode layer at a density greater than about 10 9 /cm 2 .

10. The metal-air battery of claim 7 , wherein the volume of each of the plurality of spaces is equal to or less than 120% of the maximum volume of the product formed between each of the plurality of electrolyte films and the inner wall in a corresponding one of the plurality of holes during the discharge of the metal-air battery.

11. The metal-air battery of claim 7 , wherein each of the plurality of holes has a polygonal or round shape.

12. The metal-air battery of claim 7 , wherein the plurality of holes are regularly arranged.

13. The metal-air battery of claim 7 , wherein each of the plurality of electrolyte films on the inner walls of the cathode layer when the product is not formed has a thickness of about 10 nm or less.

14. The metal-air battery of claim 7 , wherein each of the plurality of electrolyte films of the cathode comprises:
a first electrolyte portion disposed on a top surface of the anode metal layer; and
a second electrolyte portion extending from the first electrolyte portion to a corresponding one of the inner walls of the cathode layer.

15. The metal-air battery of claim 14 , wherein the cathode layer is arranged in a way such that the bottom surface of the cathode layer is in contact with the first electrolyte portion and the top surface of the cathode layer is in contact with the gas diffusion layer.

16. The metal-air battery of claim 14 , further comprising a third electrolyte portion which transmits metal ions and blocks moisture and oxygen,
wherein the third electrolyte portion is disposed between the first electrolyte portion and the anode metal layer.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Lee Heungchan
• Im Dongmin
• Lee Hyunpyo

Classifications

• H01M12/08 Primary

  composed of a half-cell of a fuel-cell type and a half-cell of the secondary-cell type · CPC title

• H01M2004/8689

  Positive electrodes · CPC title

• H01M4/8626 Primary

  characterised by the form · CPC title

• H01M4/96 Primary

  Carbon-based electrodes · CPC title

• H01M4/13 Primary

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title