Rechargeable battery

Patent metadata

Field	Value
Publication number	US-9755203-B2
Application number	US-201514680636-A
Country	US
Kind code	B2
Filing date	Apr 7, 2015
Priority date	Apr 8, 2014
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A rechargeable battery including an electrode assembly; a case accommodating the electrode assembly; and a cap assembly coupled with an opening of the case with a gasket between the cap assembly and the case, wherein the cap assembly includes a vent plate that is electrically connected to a cap plate; a middle plate that is separated from the vent plate, that includes a through-hole that is penetrated by a vent protruding from the vent plate, and that is electrically connected to the second electrode; an insulator interposed between the vent plate and the middle plate; and a sub-plate electrically connecting the vent with the middle plate, wherein at least one of the vent plate or the middle plate includes a protrusion and a groove facing the insulator, the protrusion being coupled with a complementary groove in the insulator and the groove being coupled with a complementary protrusion in the insulator.

First claim

What is claimed is:

1. A rechargeable battery, comprising:
an electrode assembly for performing charging and discharging operations;
a case accommodating the electrode assembly, the case being electrically connected to a first electrode of the electrode assembly; and
a cap assembly coupled with an opening of the case with a gasket between the cap assembly and the case, the cap assembly being electrically connected to a second electrode of the electrode assembly,
wherein the cap assembly includes:
a vent plate that is electrically connected to a cap plate;
a middle plate that is separated from the vent plate, that includes a through hole that is penetrated by a vent protruding from the vent plate, and that is electrically connected to the second electrode;
an insulator interposed between the vent plate and the middle plate; and
a sub-plate electrically connecting the vent with the middle plate,
wherein at least one of the vent plate or the middle plate includes a protrusion and a groove facing the insulator, the protrusion being coupled with a complementary groove in the insulator and the groove being coupled with a complementary protrusion in the insulator.

2. The rechargeable battery as claimed in claim 1 , wherein the protrusion and the groove of the insulator are fusion-bonded to the groove and the protrusion of the at least one of the vent plate or the middle plate.

3. The rechargeable battery as claimed in claim 1 , wherein the protrusion and groove facing the insulator includes a pair of protrusions in the vent plate and includes grooves in the vent plate adjacent to the protrusions.

4. The rechargeable battery as claimed in claim 1 , wherein the protrusion and groove facing the insulator includes a pair of protrusions in the middle plate and includes grooves in the middle plate adjacent to the protrusions.

5. The rechargeable battery as claimed in claim 1 , wherein the protrusion and the groove facing the insulator include:
a first protrusion and a first groove on the vent plate, and
a second protrusion and a second groove on the middle plate, wherein the first protrusion and the first groove are symmetrical to the second protrusion and the second groove in a stacking direction with the insulator therebetween.

6. The rechargeable battery as claimed in claim 5 , wherein the vent plate and the middle plate each include air discharging grooves on surface thereof that face the insulator.

7. The rechargeable battery as claimed in claim 6 , wherein the air discharging grooves extend lengthwise in a radial direction of the insulator and are separated from each other in a circumferential direction.

8. The rechargeable battery as claimed in claim 5 , wherein:
an angle between a bottom surface of the first groove of the vent plate and an adjacent side surface of the first protrusion of the vent plate is acute, and
an angle between a bottom surface of the second groove of the middle plate and an adjacent side surface of the second protrusion of the middle plate is acute.

9. The rechargeable battery as claimed in claim 5 , wherein:
the vent plate includes a pair of facing first protrusions,
a width of a bottom surface of the first groove of the vent plate is greater than a groove opening width between end portions of the pair of facing first protrusions that extend from the bottom surface of the first groove,
the middle plate includes a pair of facing second protrusions, and
a width of a bottom surface of the second groove of the middle plate is greater than a groove opening width between end portions of the pair of facing second protrusions that extend from the bottom surface of the second groove.

10. The rechargeable battery as claimed in claim 9 , wherein the insulator includes:
a pair of first corresponding grooves, the pair of first corresponding grooves having a shape complementary to and being coupled with the pair of first protrusions of the vent plate,
a pair of second corresponding grooves, the pair of second corresponding grooves having a shape complementary to and being coupled with the pair of second protrusions of the middle plate,
a first corresponding protrusion, the first corresponding protrusion having a shape complementary to and being coupled with the first groove of the vent plate, and
a second corresponding protrusion, the second corresponding protrusion having a shape complementary to and being coupled with the second groove of the middle plate.

11. The rechargeable battery as claimed in claim 9 , wherein:
the pair of first protrusions of the vent plate are symmetrically disposed about a center line passing through the first groove in a circumferential direction of the cap assembly,
the pair of second protrusions of the middle plate are symmetrically disposed about a center line passing through the second groove in a circumferential direction of the cap assembly,
an angle between the bottom surface of the first groove of the vent plate and an adjacent side surface of each first protrusion of the vent plate is acute,
an angle between the bottom surface of the second groove of the middle plate and an adjacent side surface of each second protrusion of the middle plate is acute,
the vent plate includes an eleventh groove at outer sides of the first groove,
the middle plate includes a twenty-first groove at outer sides of the second groove,
an angle between a bottom surface of the eleventh groove of the vent plate and another side surface of each first protrusion of the vent plate is obtuse, and
an angle between a bottom surface of the twenty-first groove of the middle plate and another side surface of each second protrusion of the middle plate is obtuse.

12. The rechargeable battery as claimed in claim 11 , wherein the insulator is coupled with the vent plate or the middle plate by at least one of:
a first fusion-bonding to the first groove and the first protrusions of the vent plate at one side thereof, or
a second fusion-bonding to the second groove and the second protrusions of the middle plate at another side thereof.

13. The rechargeable battery as claimed in claim 12 , wherein the cap assembly further includes a positive temperature coefficient element between the cap plate and the vent plate.

14. The rechargeable battery as claimed in claim 12 , wherein the insulator includes:
a first polyethylene layer adjacent to the vent plate,
a second polyethylene layer adjacent to the middle plate, and
a poly(butylene terephthalate) fiber layer integrally formed between the first and second polyethylene layers.

15. The rechargeable battery as claimed in claim 1 , wherein the middle plate is connected to the second electrode through a lead tab.

16. The rechargeable battery as claimed in claim 1 , further comprising an insulating member between a portion of the vent plate and a portion of the cap plate, wherein an end region of the vent plate is bent around the insulator to be electrically connected to a top surface of the cap plate.

17. The rechargeable battery as claimed in claim 16 , wherein the gasket continuously encloses the vent plate from below, above, and a lateral side thereof at an outer side of the insulator.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Kim Dae-Kyu
• Abe Takao

Classifications

• H01M50/186

  characterised by the disposition of the sealing members · CPC title

• H01M50/167

  by crimping · CPC title

• H01M2/1241 Primary

  Electricity · mapped topic

• H01M2200/20

  Pressure-sensitive devices · CPC title

• H01M2200/106

  PTC · CPC title