Prismatic battery having electrolyte injection-hole capable of providing excellent sealing ability

Patent metadata

Field	Value
Publication number	US-10033028-B2
Application number	US-201313834670-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Oct 8, 2010
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

Disclosed herein is a secondary battery having an electrode assembly mounted in a prismatic container, wherein the inside of an electrolyte injection hole formed in a base plate mounted to an open upper end of the prismatic container includes an upper part having a chamfered structure in which the diameter of the electrolyte injection hole is gradually decreased downward and a lower part having a non-chamfered structure continuously formed from the chamfered structure, and, when a sealing member is pressed into the electrolyte injection hole, the sealing member deformed into a shape corresponding to the electrolyte injection hole comes into tight contact with the chamfered structure due to shear stress between the chamfered structure and the sealing member and forms a sealed state due to frictional interaction between the non-chamfered structure and the sealing member. Consequently, it is possible to reduce a defect rate of secondary batteries and to improve sealability of the electrolyte injection hole without welding.

First claim

The invention claimed is:

1. A method of making a secondary battery having an electrode assembly mounted in a prismatic container, comprising:
mounting a base plate to an open upper end of the prismatic container;
forming an inside of an electrolyte injection hole to comprise an upper part having a chamfered structure in which a diameter of the electrolyte injection hole gradually decreases downward and a lower part having a non-chamfered structure continuously formed from the chamfered structure; and
simultaneously pressing and rotating a sealing member into the electrolyte injection hole to seal the electrolyte injection hole, said rotating being in a clockwise direction or in a counterclockwise direction; and
repeatedly, simultaneously rotating and pressing the sealing member at a predetermined height to seal the electrolyte injection hole after the sealing member is pressed into the electrolyte injection hole by one-time pressing,
wherein, during pressing, the sealing member is deformed into a shape corresponding to the electrolyte injection hole by the sealing member coming into tight contact with the chamfered structure due to shear stress between the chamfered structure and the sealing member and a sealed state is formed due to frictional interaction between the non-chamfered structure and the sealing member without welding.

2. The method according to claim 1 , wherein an upper end width (Wtop) of the chamfered structure satisfies a condition of 1.0×R<Wtop<1.7×R on the basis of a diameter (R) of the sealing member.

3. The method according to claim 1 , wherein a lower end width (Wbottom) of the chamfered structure satisfies a condition of 0.5×R≤Wbottom≤0.9×R on the basis of a diameter (R) of the sealing member.

4. The method according to claim 1 , wherein a width (W) of the non-chamfered structure is equal to a lower end width (Wbottom) of the chamfered structure.

5. The method according to claim 1 , wherein the pressing and rotating of the sealing member is performed by a press that reciprocates along an axis towards and away from the sealing member and rotates about said axis in the corresponding clockwise or counterclockwise direction.

6. The method according to claim 1 , wherein no welding is performed on the sealing member after the repeatedly, simultaneously rotating and pressing the sealing member at the predetermined height to seal the electrolyte injection hole.

7. A method of making a secondary battery having an electrode assembly mounted in a prismatic container, comprising:
mounting a base plate to an open upper end of the prismatic container;
forming an electrolyte injection hole in the base plate, wherein an inside of the electrolyte injection hole comprises an upper part having a chamfered structure in which a diameter of the electrolyte injection hole is gradually decreased downward and an inclined angle of the upper part is constant, and a lower part having a non-chamfered structure continuously formed from the chamfered structure;
simultaneously pressing and rotating a sealing member into the electrolyte injection hole to seal the electrolyte injection hole, said rotating being in a clockwise direction or in a counterclockwise direction; and
repeatedly, simultaneously rotating and pressing the sealing member at a predetermined height to seal the electrolyte injection hole after the sealing member is pressed into the electrolyte injection hole by one-time pressing,
wherein, during pressing, the sealing member is deformed into a shape corresponding to the electrolyte injection hole by the sealing member coming into tight contact with the chamfered structure due to shear stress between the chamfered structure and the sealing member and a sealed state is formed due to frictional interaction between the non-chamfered structure and the sealing member without welding, and
wherein the chamfered structure extends downward from an upper end of the electrolyte injection hole within a range of 0.3×D to 0.7×D on the basis of a depth (D) of the electrolyte injection hole.

8. The method according to claim 7 , wherein an upper end width (W top ) of the chamfered structure satisfies a condition of 1.0×R<W top <1.7×R on the basis of a diameter (R) of the sealing member.

9. The method according to claim 7 , wherein a lower end width (W bottom ) of the chamfered structure satisfies a condition of 0.5×R≤W bottom 0.9×R on the basis of a diameter (R) of the sealing member.

10. The method according to claim 7 , wherein a width (W) of the non-chamfered structure is equal to a lower end width (W bottom ) of the chamfered structure.

11. The method according to claim 7 , wherein a difference between an upper end width (W top ) and a lower end width (W bottom ) of the chamfered structure satisfies a condition of 8% to 42% the upper end width (W top ).

12. The method according to claim 7 , wherein a difference between a diameter (R) of the sealing member and a lower end width (W bottom ) of the chamfered structure satisfies a condition of 8% to 25% the diameter (R) of the sealing member.

13. The method according to claim 7 , further comprising forming an inclination angle of the chamfered structure between chamfer extension lines at an angle of 30 to 70 degrees.

14. The method according to claim 7 , further comprising forming the sealing member in a spherical shape, and
forming the electrolyte injection hole in a circular shape in horizontal section.

15. The method according to claim 7 , wherein the sealing member is a metal ball.

16. The method according to claim 7 , further comprising pressing the sealing member in a state in which the sealing member is located on the electrolyte injection hole; and
increasing the frictional interaction between the sealing member and the electrolyte injection hole by the downward chamfered structure to increase contact area between the sealing member and the electrolyte injection hole.

17. The method according to claim 7 , wherein the predetermined height is 1 to 5 cm from the electrolyte injection hole.

18. The method according to claim 7 , further comprising pressing the sealing member 5 to 20 times.

19. The method according to claim 1 , wherein an inclined angle of the upper part of the electrolyte injection hole is constant.

20. The method according to claim 7 , wherein the pressing and rotating of the sealing member is performed by a press that reciprocates along an axis towards and away from the sealing member and rotates about said axis in the corresponding clockwise or counterclockwise direction.

21. The method according to claim 7 , wherein no welding is performed on the sealing member after the repeatedly, simultaneously rotating and pressing the sealing member at the predetermined height to seal the electrolyte injection hole.

Assignees

• Lg Chemical Ltd

Inventors

• Kim Hong Kue
• Lee Seungtae
• Lee Eun Jung
• Kim Hakkyun

Classifications

• H01M50/103 Primary

  prismatic or rectangular (H01M50/109, H01M50/11 take precedence) · CPC title

• H01M50/627

  Filling ports · CPC title

• H01M2/365

  Electricity · mapped topic

• H01M2/361 Primary

  Electricity · mapped topic

• H01M2/0217

  Electricity · mapped topic