Curved electrode stack and battery pack including the same

Patent metadata

Field	Value
Publication number	US-2016133987-A1
Application number	US-201414893362-A
Country	US
Kind code	A1
Filing date	May 8, 2014
Priority date	Jul 31, 2013
Publication date	May 12, 2016
Grant date	—

Abstract

Disclosed herein are an electrode stack including at least one positive electrode, at least one negative electrode, and at least one separator, wherein the positive electrode, the negative electrode, and the separator are stacked such that the separator is disposed between the positive electrode and the negative electrode, one end of each of the positive electrode and the negative electrode does not intersect the other end of each of the positive electrode and the negative electrode, a stacked surface of each of the positive electrode, the negative electrode, and the separator includes a curved surface, and the negative electrode has an arc length equal to or greater than that of the positive electrode while the separator has an arc length greater than that of the positive electrode in a state in which the positive electrode, the negative electrode, and the separator are curved, and a battery pack including the same.

First claim

1 . An electrode stack comprising:
at least one positive electrode; at least one negative electrode; and at least one separator disposed between the positive electrode and the negative electrode; wherein the positive electrode, the negative electrode, and the separator are stacked, one end of each of the positive electrode and the negative electrode does not intersect the other end of each of the positive electrode and the negative electrode, a stacked surface of each of the positive electrode, the negative electrode, and the separator comprises a curved surface, and the negative electrode has an arc length equal to or greater than that of the positive electrode while the separator has an arc length greater than that of the positive electrode in a state in which the positive electrode, the negative electrode, and the separator are curved.

2 . The electrode stack according to claim 1 , wherein the negative electrode has a length equivalent to 1.1 to 1.3 times that of the positive electrode.

3 . The electrode stack according to claim 1 , wherein the separator has a length equivalent to 1.1 to 1.3 times that of the positive electrode.

4 . The electrode stack according to claim 1 , wherein the electrode stack comprises at least one non-curved surface.

5 . The electrode stack according to claim 1 , wherein a side surface of the electrode stack that is not parallel to the stacked surface comprises one or more non-curved surfaces.

6 . The electrode stack according to claim 5 , wherein electrode tabs are formed at the non-curved surfaces.

7 . The electrode stack according to claim 5 , wherein both a positive electrode tab and a negative electrode tab are formed at one of the non-curved surfaces of the electrode stack.

8 . The electrode stack according to claim 5 , wherein a positive electrode tab is formed at one of the non-curved surfaces of the electrode stack, and a negative electrode tab is formed at the other of the non-curved surfaces of the electrode stack.

9 . The electrode stack according to claim 1 , wherein one end of each of the positive electrode, the negative electrode, and the separator does not intersect the other end of each of the positive electrode, the negative electrode, and the separator.

10 . The electrode stack according to claim 9 , wherein the separator is laminated to one surface or opposite surfaces of at least one selected from between the positive electrode and the negative electrode.

11 . The electrode stack according to claim 10 , wherein the electrode stack comprises an electrode group comprising at least one positive electrode, at least one negative electrode, and at least one separator, the electrode group being configured to have a structure in which the positive electrode, the separator, and the negative electrode are laminated in a state in which the separator is disposed between the positive electrode and the negative electrode.

12 . The electrode stack according to claim 11 , wherein the electrode group is configured to have a structure in which outermost ones of the electrodes have the same polarity or different polarities.

13 . The electrode stack according to claim 12 , wherein at least one of the outermost electrodes is laminated to the separators in a state in which the at least one of the outermost electrodes is disposed between the separators.

14 . The electrode stack according to claim 10 , wherein the electrode stack comprises an electrode element comprising one selected from between a positive electrode and a negative electrode and at least one separator, the electrode element being configured to have a structure in which one selected from between the positive electrode and the negative electrode is laminated to the separator.

15 . The electrode stack according to claim 14 , wherein the electrode element is configured to have a structure in which one selected from between the positive electrode and the negative electrode is laminated to the separators in a state in which one selected from between the positive electrode and the negative electrode is disposed between the separators.

16 . The electrode stack according to claim 1 , wherein the at least one separator comprises a first separator and a second separator, and the second separator wraps side surfaces of the electrodes, at which no electrode terminals are formed.

17 . The electrode stack according to claim 16 , wherein one end of the second separator intersects the other end of the second separator.

18 . A battery cell comprising an electrode stack according to claim 1 mounted in a battery case together with an electrolyte.

19 . The battery cell according to claim 18 , wherein the battery case is a metal can or a pouch-shaped battery case made of a laminate sheet comprising a metal layer and a resin layer.

20 . The battery cell according to claim 18 , wherein the battery cell is a lithium ion polymer battery, a lithium ion battery, or a lithium polymer battery.

21 . A battery pack comprising:
a battery cell comprising an electrode stack according to claim 1 , a non-aqueous electrolyte containing lithium salt, electrode terminals having opposite polarities, and a battery cell case, wherein the electrode stack is received in the battery cell case together with the electrolyte, both of the positive electrode terminal and the negative electrode terminal are formed at a first surface of the battery cell case, and the first surface comprises a first curved surface; and a protection circuit module connected to the positive electrode terminal and the negative electrode terminal, a second surface of the protection circuit module facing the first surface comprising a second curved surface identical to or similar to the first curved surface.

22 . The battery pack according to claim 21 , wherein the first curved surface and the second curved surface are similar to each other within a similarity ratio of 1:0.90 to 1:0.99 or 1:1.01 to 1:1.10.

23 . The battery pack according to claim 21 , wherein the first curved surface has a radius of curvature (R1) of 35 mm to 900 mm, and the second curved surface has a radius of curvature (R2) of 35 mm to 900 mm.

24 . The battery pack according to claim 23 , wherein the radius of curvature (R1) of the first curved surface is equal to the radius of curvature (R2) of the second curved surface.

25 . The battery pack according to claim 21 , wherein the protection circuit module is configured to have a printed circuit board structure in which an electric circuit for preventing overcharge or overdischarge and enabling flow of rated current is printed, the second curved surface is one surface of the printed circuit board, a safety element and a connection terminal are coupled to one surface of the printed circuit board, and the other surface of the printed circuit board comprises an external input and output terminal connected to a predetermined external device.

26 . A device comprising a battery pack according to claim 21 .

27 . The device according to claim 26 , wherein the device is a smart phone, a mobile phone, a laptop computer, a tablet PC, a clock, a television, or glasses.

Assignees

• Lg Chemical Ltd

Inventors

• Choi Eun Seok
• Cho Shin Hyo
• Chung Jae Bin
• Kim Dong-Myung

Classifications

• H01M10/052

  Li-accumulators · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M10/0436

  Small-sized flat cells or batteries for portable equipment · CPC title

• H01M10/058 Primary

  Construction or manufacture · CPC title

• H01M2010/4271

  Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing · CPC title