Secondary battery including cap plate comprising reinforcing element

Patent metadata

Field	Value
Publication number	US-9722234-B2
Application number	US-201414166737-A
Country	US
Kind code	B2
Filing date	Jan 28, 2014
Priority date	Oct 17, 2013
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

A secondary battery, which can improve safety during a longitudinal compression test by reinforcing strength of a cap plate, is provided. In one embodiment, the secondary battery includes an electrode assembly, a can accommodating the electrode assembly, and cap plate coupled to a top portion of the can and sealing the can, wherein a reinforcement unit is formed on at least one side of the cap plate.

First claim

What is claimed is:

1. A secondary battery comprising:
an electrode assembly having a first electrode terminal;
a can that receives the electrode assembly;
a cap plate having ends and side walls interconnecting the ends and coupled to the can so as to seal the electrode assembly within the can, wherein the cap plate defines a longitudinal axis and wherein the cap plate includes at least one reinforcing element that is dimensioned and located on the cap plate so that the can deforms about a first point in response to compressive forces exerted in the direction of the longitudinal axis of the cap plate wherein the reinforcing element comprises at least one groove that has exposed side walls and an exposed bottom surface and a shape that corresponds to the shape of an end of the cap plate wherein the thickness of the cap plate in the groove is substantially constant over the surface area of the groove and wherein a weakened portion is formed on the cap plate in a first location so as to define the first point and wherein the weakened portion comprises a portion of the cap plate of reduced thickness and wherein the first electrode terminal extends through the cap plate in the weakened portion and is electrically isolated from the cap plate and wherein the reinforcing element and the weakened portion of the cap plate are spaced from each other with the reinforcing element being spaced between the weakened portion and at least one of the ends of the cap plate.

2. The secondary battery of claim 1 , further comprising a terminal plate that is positioned between the cap plate and the can and wherein the first point is selected so that deformation of the cap plate about the first point results in the terminal plate short circuiting with the can.

3. The secondary battery of claim 1 , wherein the cap plate includes a first and second surface and wherein the reinforcing element comprises at least one groove formed on the cap plate located to one side of the first point along the longitudinal axis of the cap plate.

4. The secondary battery of claim 3 , wherein the at least one groove comprises a first and a second groove located on opposite sides of the first point along the longitudinal axis of the cap plate.

5. The secondary battery of claim 3 , further comprising a protrusion part that is positioned on the surface of the cap plate opposite the groove.

6. The secondary battery of claim 5 , wherein the protrusion part protrudes outward from the surface the same amount as the groove extends into the cap plate and has substantially the same contour as the at least one groove.

7. The secondary battery of claim 1 , wherein the at least one reinforcing element comprises a first and a second reinforcing element that are arranged on opposite sides of the first point along the longitudinal axis of the cap plate.

8. The secondary battery of claim 7 , wherein the first and second reinforcing elements are symmetrical about the first point.

9. The secondary battery of claim 1 , wherein a ratio of a horizontal length of the reinforcement element to a horizontal length of the cap plate is between the ratios of 1:2 to 1:20 wherein the horizontal length is in a direction that is parallel to the longitudinal axis.

10. The secondary battery of claim 1 , wherein a horizontal length of the reinforcement element is 5% to 50% of a horizontal length of the cap plate.

11. The secondary battery of claim 1 , wherein a ratio of a width of the reinforcement element to a width of the cap plate is between the ratios of 1:2 to 1:20 wherein the width is in a direction that is perpendicular to the longitudinal axis.

12. The secondary battery of claim 1 , wherein a width of the reinforcement element is 5% to 50% of a width of the cap plate.

13. The secondary battery of claim 1 , wherein a ratio of the vertical size of the of the reinforcement element to a thickness of the cap plate is between the ratios of 1:1.25 to 1:10.

14. The secondary battery of claim 1 , wherein the reinforcement element is spaced apart from an end of the cap plate, and a distance between the cap plate and the reinforcement element is 5% to 15% of the horizontal length of the cap plate.

15. The secondary battery of claim 1 , further comprising a safety vent formed in the can.

16. The secondary battery of claim 1 , wherein the reinforcing element reinforces the strength of the cap plate by inhibiting at least one side of the cap plate from being deformed due to a force applied from both sides of the can along the longitudinal axis of the cap plate.

17. The secondary battery of claim 1 , wherein the at least one reinforcement member comprises a protrusion.

18. The secondary battery of claim 1 , wherein the first point is positioned at the center point of the longitudinal axis of the cap plate.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Seong Jaeil
• Yoshio Hideaki
• Yun Jiwon

Classifications

• H01M10/0436 Primary

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

• H01M10/0431 Primary

  Cells with wound or folded electrodes (H01M10/045 takes precedence) · CPC title

• H01M50/147 Primary

  Lids or covers · CPC title

• H01M50/3425

  in the form of rupturable membranes or weakened parts, e.g. pierced with the aid of a sharp member · CPC title

• H01M50/169

  by welding, brazing or soldering · CPC title