Battery and method of manufacturing the same

Patent metadata

Field	Value
Publication number	US-11757094-B2
Application number	US-202016939208-A
Country	US
Kind code	B2
Filing date	Jul 27, 2020
Priority date	Aug 1, 2019
Publication date	Sep 12, 2023
Grant date	Sep 12, 2023

Abstract

A battery includes a cathode layer, a cathode current collector on the cathode layer, an anode layer on the cathode layer, an anode current collector on the anode layer, a separator between the cathode layer and the anode layer, and an electrolyte, wherein the cathode layer includes a plurality of crystal grains of a cathode active material and aligned in a first direction, and at least one groove formed in a direction perpendicular to an upper surface of the cathode layer that is in contact with the separator, and wherein a side surface of the cathode layer exposed by the at least one groove is aligned with a <101> crystal direction, a <hk0> crystal direction, wherein h and k are integers greater than or equal to 1, or a combination thereof, of the crystal grains of the cathode active material.

First claim

What is claimed is:

1. A battery comprising:
a cathode layer;
a cathode current collector on the cathode layer;
an anode layer on the cathode layer;
an anode current collector on the anode layer;
a separator between the cathode layer and the anode layer; and
an electrolyte between the cathode layer and the anode layer,

wherein the cathode layer comprises
a plurality of crystal grains of a cathode active material and aligned in a first direction, and
at least one groove formed in a direction perpendicular to an upper surface of the cathode layer that is in contact with the separator, and
wherein a side surface of the cathode layer exposed by the at least one groove is aligned with a <101> crystal direction, a <hk0> crystal direction wherein h and k are integers greater than or equal to 1, or a combination thereof, of the crystal grains of the cathode active material.

2. The battery of claim 1 ,
wherein the at least one groove is between a first outer side surface of the cathode layer and a second outer side surface of the cathode layer, wherein the second outer side surface is opposite the first outer side surface, and
wherein crystal grains of the first side surface and crystal grains of the second side surface each have a same crystal direction as crystal grains of the side surface of the cathode layer exposed by the at least one groove.

3. The battery of claim 1 , wherein the at least one groove is a slit-shaped groove.

4. The battery of claim 1 , wherein the at least one groove has a trench shape.

5. The battery of claim 1 ,
wherein a width of the at least one groove is less at a bottom surface of the cathode layer than a width of the at least one groove at an upper surface of the cathode layer, and
wherein a depth of the at least one groove is greater than a distance between an end of the at least one groove proximate the bottom surface of the cathode layer and the bottom surface of the cathode layer.

6. The battery of claim 1 ,
wherein the at least one groove comprises a plurality of grooves, and
wherein depths of the plurality of grooves are within 1 standard deviation, based on total depths of the plurality of grooves.

7. The battery of claim 1 , wherein a ratio R in Equation 1 is in a range from about 2.7 to about 10.6,
R =( I (101)+ I (110))/ I (003)  Equation 1

wherein
I(101) is an intensity of an X-ray diffraction peak corresponding to a (101) crystal plane,
I(110) is an intensity of an X-ray diffraction peak corresponding to a (110) crystal plane,
I(003) is an intensity of an X-ray diffraction peak corresponding to a (003) crystal plane, when determined using Cu Kα radiation.

8. The battery of claim 1 , wherein a relative density of the cathode layer is about 90% to about 99%, based on a density of the of the cathode layer before sintering.

9. The battery of claim 5 , wherein
a thickness of the cathode layer is in a range from about 30 micrometers to about 200 micrometers, and
a distance between the end of a groove proximate to the bottom surface of the cathode layer and the bottom surface of the cathode layer is in a range from about 5 micrometers to about 50 micrometers.

10. The battery of claim 1 , wherein the cathode active material layer is isostructural with α-NaFeO 2 .

11. A method of manufacturing a battery, the method comprising:
providing a cathode layer comprising a plurality of crystal grains of a cathode active material;
forming at least one groove between a first side surface of the cathode layer and a second side surface of the cathode layer;
disposing a cathode current collector on a surface of the cathode layer under the at least one groove;
providing an anode layer;
disposing an anode current collector on a surface of the anode layer;
disposing a separator on a surface of the cathode layer in which the at least one groove is formed;
supplying an electrolyte to the separator; and
disposing the anode layer on the separator to manufacture the battery,
wherein a side surface of the cathode layer exposed by the at least one groove is aligned with a <101> crystal direction, a <hk0> crystal direction wherein h and k are integers greater than or equal to 1, or a combination thereof, of the crystal grains of the cathode active material.

12. The method of claim 11 , further comprising forming the cathode layer by:
disposing a cathode active material on a substrate to form a cathode active material tape;
forming the at least one groove in a direction perpendicular to a surface of the cathode active material tape; and
sintering the cathode active material tape to form the cathode layer.

13. The method of claim 12 , wherein the forming of the at least one groove comprises forming at least one slit in the cathode active material tape.

14. The method of claim 12 , wherein the forming of the at least one groove comprises forming at least one trench in the cathode active material tape.

15. The method of claim 11 , wherein the forming of the at least one groove comprises forming the at least one groove in a direction from an upper surface towards a bottom surface of the cathode layer, and
a depth of the at least one groove is greater than a distance between an end of the at least one groove proximate the bottom surface of the cathode layer and a bottom surface of the cathode layer.

16. The method of claim 11 , wherein a ratio R in Equation 1 is in a range from about 2.7 to about 10.6,
R =( I (101)+ I (110))/ I (003)  Equation 1

wherein
I(101) is an intensity of an X-ray diffraction peak corresponding to a (101) crystal plane,
I(110) is an intensity of an X-ray diffraction peak corresponding to a (110) crystal plane,
I(003) is an intensity of an X-ray diffraction peak corresponding to a (003) crystal plane, when determined using Cu Kα radiation.

17. The method of claim 13 , wherein a plurality of slits having a same depth are formed in the cathode active material tape.

18. The method of claim 11 , wherein a relative density of the cathode layer is about 90% to about 99%, based on a density of the of the cathode layer before sintering.

19. A cathode layer comprising:
a plurality of crystal grains of a cathode active material and aligned in a first direction; and
at least one groove formed in a direction perpendicular to a surface of the cathode layer,
wherein a side surface of the cathode layer exposed by the at least one groove is aligned with a <101> crystal direction, a <hk0> crystal direction wherein h and k are integers greater than or equal to 1, or a combination thereof, of the crystal grains of the cathode active material.

20. The cathode active material layer of claim 18 , wherein the cathode active material layer is isostructural with α-NaFeO 2 .

Assignees

• Samsung Electronics Co Ltd

Inventors

• Jeong Huisu
• Park Hwiyeol
• Kim Kyounghwan
• Shon Jeongkuk
• Lee Junhyeong
• Lim Sungjin
• Heo Jin S

Classifications

• H01M10/0525 Primary

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/13 Primary

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

• H01M4/366 Primary

  as layered products · CPC title

• H01M2004/021

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

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title