Prismatic battery cell having two or more case members

Patent metadata

Field	Value
Publication number	US-10770694-B2
Application number	US-201515502875-A
Country	US
Kind code	B2
Filing date	Sep 22, 2015
Priority date	Sep 25, 2014
Publication date	Sep 8, 2020
Grant date	Sep 8, 2020

Abstract

Disclosed herein is a prismatic battery cell including an electrode assembly including a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode, the electrode assembly having a positive electrode terminal and a negative electrode terminal protruding from at least one side of the positive electrode and the negative electrode, two or more case members coupled to each other so as to have a shape corresponding to the external shape of the electrode assembly such that the case members surround the electrode assembly, the case members having a predetermined opening, through which one surface of the electrode assembly, at least, corresponding to protruding portions of the positive electrode terminal and the negative electrode terminal is exposed, and a cap plate coupled to the opening of the case members in a sealed state.

First claim

The invention claimed is:

1. A prismatic battery cell comprising:
an electrode assembly comprising a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode, the electrode assembly having a positive electrode terminal and a negative electrode terminal protruding from at least one side of the positive electrode and the negative electrode, wherein the electrode assembly includes a step formed on an outer surface thereof;
two or more case members coupled to each other so as to have a shape corresponding to an external shape of the electrode assembly such that the case members surround the electrode assembly, the case members having a predetermined opening, through which one surface of the electrode assembly corresponding to protruding portions of the positive electrode terminal and the negative electrode terminal is exposed; and
a cap plate coupled to the opening of the case members in a sealed state,
wherein a first case member of the two or more case members includes a first step coupling portion, a second case member of the two or more case members includes a second step coupling portion, and an outer surface of the first step coupling portion and an inner surface of the second step coupling portion are directly coupled to each other,
wherein the case members include a step in at least one outer surface thereof, and
wherein the step of the case members is formed to correspond to the step of the electrode assembly, and
wherein the positive electrode terminal and the negative electrode terminal are electrically connected to the cap plate in the sealed state.

2. The prismatic battery cell according to claim 1 , wherein the electrode assembly is configured to have a structure in which unit cells, each of which is configured to have a stacked structure comprising a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode, are successively folded using a separation film.

3. The prismatic battery cell according to claim 1 , wherein the positive electrode terminal and the negative electrode terminal protrude from the same side of the electrode assembly.

4. The prismatic battery cell according to claim 3 , wherein the case members are coupled to each other so as to have a structure in which the case members surround the other surfaces of the electrode assembly such that the case members have one opening, through which one surface of the electrode assembly corresponding to the protruding portions of the positive electrode terminal and the negative electrode terminal are exposed.

5. The prismatic battery cell according to claim 3 , wherein the case members are coupled to each other so as to have a structure in which the case members surround the other surfaces of the electrode assembly such that the case members have two openings, through which one surface of the electrode assembly corresponding to the protruding portions of the positive electrode terminal and the negative electrode terminal and another surface of the electrode assembly opposite to one surface of the electrode assembly are exposed.

6. The prismatic battery cell according to claim 4 , wherein the cap plate is coupled to the opening or each opening of the case members, and the cap plate coupled to one surface of the electrode assembly corresponding to the protruding portions of the positive electrode terminal and the negative electrode terminal is electrically connected to the positive electrode terminal and the negative electrode terminal of the electrode assembly.

7. The prismatic battery cell according to claim 1 , wherein the case members are two case members having the same shape.

8. The prismatic battery cell according to claim 1 , wherein the case members are two case members having different shapes.

9. The prismatic battery cell according to claim 1 , wherein each of the case members is manufactured by forging, blanking, or cutting a metal sheet.

10. The prismatic battery cell according to claim 1 , wherein cap-coupling portions are formed in the case members or in the cap plate.

11. The prismatic battery cell according to claim 1 , wherein the case members include concave cap-coupling portions coupled to the cap plate, or the cap plate includes convex cap-coupling portions coupled to the case members.

12. The prismatic battery cell according to claim 1 , wherein the case members include concave cap-coupling portions coupled to the cap plate, and the cap plate includes convex cap-coupling portions coupled to the case members.

13. The prismatic battery cell according to claim 10 , wherein the cap-coupling portions are configured to engage with each other.

14. The prismatic battery cell according to claim 1 , wherein coupling between the case members and coupling between the case members and the cap plate are achieved by laser welding.

15. The prismatic battery cell according to claim 1 , wherein the prismatic battery cell is configured to have a structure in which the case members are coupled to each other so as to surround the other surfaces of the electrode assembly in the sealed state in which the positive electrode terminal and the negative electrode terminal of the electrode assembly are electrically connected to the cap plate.

16. The prismatic battery cell according to claim 15 , wherein prismatic battery cell is a lithium secondary battery.

17. A device comprising one or more prismatic battery cells according to claim 1 .

18. The device according to claim 17 , wherein the device is selected from a group consisting of a mobile phone, a tablet computer, a laptop computer, a power tool, a wearable electronic device, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, and a power storage apparatus.

19. A method of manufacturing a prismatic battery cell according to claim 1 , the method comprising:
(a) preparing unit cells, each of which is configured to have a stacked structure comprising at least one positive electrode, at least one negative electrode, and at least one separator disposed between the at least one positive electrode and the at least one negative electrode;
(b) sequentially folding the unit cells prepared at step (a) in a state in which the unit cells are placed on a long sheet type separation film to prepare an electrode assembly;
(c) electrically connecting a positive electrode terminal and a negative electrode terminal of the electrode assembly prepared at step (b) to a cap plate; and
(d) coupling case members and the cap plate so as to surround the electrode assembly, the positive electrode terminal and the negative electrode terminal of which are electrically connected to the cap plate at step (c), injecting an electrolyte into the case members, and sealing the case members.

20. The method according to claim 19 , wherein the unit cells are configured such that outermost electrodes of the unit cells having different polarities face each other in a state in which the separation film is disposed between the outermost electrodes of the unit cells.

21. The method according to claim 19 , wherein coupling between the case members and coupling between the case members and the cap plate are achieved by laser welding.

22. The method according to claim 19 , wherein step (d) comprises injecting the electrolyte into the case members through an electrolyte injection hole formed in the cap plate.

Assignees

• Lg Chemical Ltd

Inventors

• Kim Ki Tae
• Yun Hyung Ku
• Kim Dong-Myung
• Kim Hyojin

Classifications

• H01M50/564

  characterised by their manufacturing process · CPC title

• H01M50/553

  Terminals adapted for prismatic, pouch or rectangular cells · CPC title

• H01M50/169

  by welding, brazing or soldering · CPC title

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M50/15

  for prismatic or rectangular cells (H01M50/153 takes precedence) · CPC title