Secondary battery

Abstract

The secondary battery according to the present invention has a vent deformation accelerator which promotes the operation of a vent formed on a wide side of a can in the cap plate, a bottom side of a can or a narrow side of a can so that the vent operates at the low pressure. Therefore, a secondary battery is provided with a vent which operates at a lower pressure than the operating pressure of existing vents. Also, the vent can be formed relatively thick when the operating vent which operates at the same pressure as the operating pressure of an existing vent so that it can avoid forming a vent having a minute thickness, thereby reducing the manufacturing costs and processing time.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the present invention and many of the attendant advantages thereof, will be readily apparent as the present invention becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:

FIG. 1 is an exploded perspective view of a secondary battery of an embodiment of the present invention;

FIGS. 2A and 2B are respectively a plane figure and a sectional drawing of a cap assembly of the secondary battery of FIG. 1;

FIG. 3 is a view of a secondary battery before and after swelling thereof;

FIG. 4 is a tension stress distribution drawing of a wide side of the can, the stress being caused by an internal pressure of the can;

FIGS. 5A to 5D are perspective views of before and after swelling of a secondary battery of another embodiment of the present invention;

FIG. 6 is a view of a secondary battery of another embodiment according to the present invention before and after swelling thereof; and

FIG. 7 is a view of a secondary battery of still another embodiment according to the present invention before and after swelling thereof.

Claims

1. A secondary battery comprising: a can having one side open and including an electrode assembly;a cap assembly having a cap plate attached to the open upper side of the can;a vent arranged on a wide side surface of the can; anda vent deformation accelerator which is thinner than other parts of the battery and arranged on one of a narrow side of the can or on a bottom side of the can or on the cap plate.

2. The secondary battery as claimed in claim 1, wherein the vent is arranged on a closed corner portion among four corner portions of the wide side surface of the can by the vent deformation accelerator.

3. The secondary battery as claimed in claim 2, wherein the vent is arranged in a diagonal direction of the wide side surface of the can.

4. The secondary battery as claimed in claim 3, wherein the vent has a shape of one of one side of an open pentagon or an open circle loop.

5. The secondary battery as claimed in claim 2, wherein the shape of the vent is determined according to creases produced on a corner portion of the can when transformed by internal pressure in the can.

6. The secondary battery as claimed in claim 3, wherein the shape of the vent is one of ‘’ or ‘’, or ‘’ or ‘’.

7. The secondary battery as claimed in claim 1, wherein the vent comprises a depressed notch.

8. The secondary battery as claimed in claim 2, wherein the vent comprises a depressed notch.

9. The secondary battery as claimed in claim 3, wherein the vent comprises a depressed notch.

10. The secondary battery as claimed in claim 4, wherein the vent comprises a depressed notch.

11. The secondary battery as claimed in claim 5, wherein the vent comprises a depressed notch.

12. The secondary battery as claimed in claim 6, wherein the vent comprises a depressed notch.