POUCH TYPE CASE AND BATTERY PACK INCLUDING THE SAME

• US 20110274955A1
• Filed: 07/20/2011
• Published: 11/10/2011
• Est. Priority Date: 03/19/2010
• Status: Active Grant

• Current Assignee: LG Energy Solution Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Park, Hyun Woo, Shin, Young Joon, Park, Hyo Seok
• Granted Patent: US 8,426,057 B2
• Time in Patent Office: Days
• US Class Current: 429/94
• CPC Class Codes: H01M 10/0413 Large-sized flat cells or batteries for motive or stationary systems with plate-like electrodes
• CPC Class Codes: H01M 10/045 Cells or batteries with folded plate-like electrodes
• CPC Class Codes: H01M 10/0459 Cells or batteries with folded separator between plate-like electrodes
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0583 of accumulators with folded construction elements except wound ones, i.e. folded positive or negative electrodes or separators, e.g. with "Z"-shaped electrodes or separators
• CPC Class Codes: H01M 10/0587 of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
• CPC Class Codes: H01M 2200/20 Pressure-sensitive devices
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 50/105 Pouches or flexible bags
• CPC Class Codes: H01M 50/178 for pouch or flexible bag cells
• CPC Class Codes: H01M 50/30 Arrangements for facilitating escape of gases
• CPC Class Codes: H01M 50/469 tubular or cylindrical
• CPC Class Codes: H01M 50/548 on opposite sides of the cell
• CPC Class Codes: H01M 50/55 on the same side of the cell
• CPC Class Codes: H01M 50/578 in response to pressure
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

The present invention relates to a pouch type case having trimming portions formed on both sides or four corners thereof and a battery pack including the same. The trimming portions are formed on the corners of the pouch type case such that the trimming portions are indented toward an electrode assembly accommodating part to reduce a unit area so as to increase pressure applied to unit cells when a battery pack is assembled, thereby facilitating assembling of the battery pack and increasing cell capacity per unit area. Furthermore, the unit cells can be fixed in the battery pack more stably. The pouch type case reduces the unit area so as to include a relatively large number of cells for pressure applied to the cells when the battery pack is assembled to thereby increase the cell capacity.

Claims

1. A pouch type case comprising a space accommodating an electrode assembly comprising a positive plate, a negative plate and a separator interposed between the positive plate and the negative plate and a sealing part sealing up an upper case and a lower case,

wherein a portion of the space and sealing part, which corresponds to at least one of the left and right sides of an electrode lead projected to the outside of the case, includes a trimming portion intended toward the electrode assembly.

2. The pouch type case of claim 1, wherein the trimming portion is spaced apart from the electrode lead and the top end of the electrode assembly by a distance corresponding to the width of the sealing part.

3. The pouch type case of claim 1, wherein the trimming portion is spaced apart from the electrode lead by longer than 6 mm and shorter than the width of the electrode lead and spaced apart from the top end of the electrode assembly by longer than 3 mm and shorter than the length of the electrode lead.

4. The pouch type case of claim 1, wherein the trimming portion has one of circular, oval, straight-line, rectangular, triangular, parabola and V shapes.

5. The pouch type case of claim 1, wherein the pouch type case includes trimming portions respectively formed on the corners of the case and the trimming portions have the same shape or different shapes.

6. The pouch type case of claim 1, wherein the electrode assembly has an anode lead and a cathode lead projected in different directions.

7. The pouch type case of claim 6, wherein the anode lead and the cathode lead are projected from one of a shorter side and a longer side of the electrode assembly.

8. The pouch type case of claim 6, wherein portions of the space and the sealing part, which correspond to the left and right sides of the anode lead and the cathode lead, respectively include trimming portions indented toward the electrode assembly.

9. The pouch type case of claim 1, wherein the electrode assembly has an anode lead and a cathode lead projected in the same direction.

10. The pouch type case of claim 9, wherein the direction in which the anode lead and the cathode lead are projected corresponds to one of the shorter side and longer side of the electrode assembly.

11. The pouch type case of claim 9, wherein portions of the space and the sealing part and the space, which correspond to both corners of the side from which the anode lead and the cathode lead are projected, respectively include trimming portions intended toward the electrode assembly.

12. The pouch type case of claim 9, wherein a portion of the space and the sealing part between the anode lead and the cathode lead includes a trimming portion intended toward the electrode assembly.

13. The pouch type case of claim 12, wherein the trimming portion is spaced apart from the anode and cathode leads and the top end of the electrode assembly by a distance corresponding to the width of the sealing part.

14. The pouch type case of claim 13, wherein the trimming portion is formed in a parabola shape having a vertex corresponding to a point spaced apart from the top end of the electrode assembly by at least 3 mm.

15. The pouch type case of claim 13, wherein the trimming portion is formed in an inverted triangle having a vertex corresponding to a point spaced apart from the top end of the electrode assembly by at least 3 mm.

16. The pouch type case of claim 9, wherein portions of the space and the sealing part, which correspond to both corners of the side from which the anode and cathode leads are projected, and a portion of the space and the sealing part between the anode and cathode leads respectively include trimming portions indented toward the electrode assembly.

17. The pouch type case of claim 1, wherein the width of the sealing part including the trimming portion is maintained.

18. The pouch type case of claim 1, wherein at least one side of the upper case and at least one side of the lower case are connected to each other

19. The pouch type case of claim 1, wherein the upper case and the lower case are separated from each other and respectively have spaces accommodating the electrode assembly.

20. A lithium secondary battery comprising the pouch type case and the electrode assembly according to claim 1.

21. The lithium secondary battery of claim 20, wherein the electrode assembly includes a trimming portion having the same shape as the trimming portion formed at the pouch type case at a portion corresponding to the trimming portion formed at the case.

22. The lithium secondary battery of claim 20, wherein the electrode assembly corresponds to one of a stack &

folding electrode assembly manufactured in such a manner that a bi-cell and a full-cell are arranged on a long separating film in an intersecting manner and folded, a stack &

folding electrode assembly manufactured in such a manner that only the bi-cell is placed on the separating film and folded, a stack &

folding electrode assembly manufactured in such a manner that only the full-cell is placed on the separating film and folded, a Z-shaped stack &

folding electrode assembly manufactured by folding the bi-cell or the full-cell using the separating film in a zigzag direction, a stack &

folding electrode assembly manufactured by continuously folding the bi-cell or full-cell in the same direction, an electrode assembly manufactured in such a manner that an anode and a cathode are arranged on a long separating film in an intersecting manner and folded, a jelly-roll type electrode assembly manufactured by winding a positive plate, a separator and a negative plate, sequentially arranged, in one direction, and a stack-type electrode assembly.

23. The lithium secondary battery of claim 20, wherein trimming portions are previously formed at the upper case and the lower case of the pouch type case, and then the sealing part is sealed through thermal bonding.

24. A battery pack comprising the lithium secondary battery according to claim 20.

25. The battery pack of claim 24, wherein the battery pack includes a holder arranged on the trimming portions formed at the pouch type case of the lithium secondary battery.

26. The battery pack of claim 25, wherein the cross-sectional shape of the holder corresponds to the shape of the trimming portions formed at the pouch type case.

27. The battery pack of claim 24, wherein the battery pack is used as a power supply of a medium-and-large-size device.

28. The battery pack of claim 27, wherein the medium-and-large-size device corresponds to a power tool, an electric vehicle such as a hybrid electric vehicle and a plug-in hybrid electric vehicle, an electric two-wheeled vehicle including E-bike and E-scooter, an electric golf cart, an electric truck, an electric commercial vehicle, or an electric power storage system.