Battery case, secondary battery, and method for manufacturing same

Patent metadata

Field	Value
Publication number	US-2018358643-A1
Application number	US-201615579335-A
Country	US
Kind code	A1
Filing date	Nov 30, 2016
Priority date	Dec 16, 2015
Publication date	Dec 13, 2018
Grant date	—

Abstract

The present invention relates to a secondary battery. The secondary battery comprises: an electrode assembly having a through-hole; and a battery case accommodating the electrode assembly and having a through-type opening into which the through-hole is inserted, wherein the battery case comprises: a lower case comprising an accommodation part accommodating the electrode assembly and a lower inner sealing part having the through-type opening into which the through-hole is inserted; and an upper case comprising a cover part coupled to an upper portion of the lower case to finish the accommodation part and an upper inner sealing part having a coupling hole to which a front end of the lower inner sealing part is coupled.

First claim

1 . A secondary battery comprising:
an electrode assembly having a through-hole; and a battery case accommodating the electrode assembly and having a through-type opening into which the through-hole is inserted, wherein the battery case comprises: a lower case comprising an accommodation part accommodating the electrode assembly and a lower inner sealing part having the through-type opening into which the through-hole is inserted; and an upper case comprising a cover part coupled to an upper portion of the lower case to finish the accommodation part and an upper inner sealing part having a coupling hole to which a front end of the lower inner sealing part is coupled.

2 . The secondary battery of claim 1 , wherein the upper inner sealing part has an inner sealing surface having the coupling hole to which the front end of the lower inner sealing part is coupled and a connection surface having an inner end coupled to a bottom surface of the inner sealing surface and an outer end connected to the cover part, and
an opening groove is defined between the inner sealing surface and the connection surface.

3 . The secondary battery of claim 2 , wherein the lower inner sealing part disposed on the through-type opening and the inner sealing surface disposed on the opening groove are press-fitted at the same time to seal the lower inner sealing part and the upper inner sealing part.

4 . The secondary battery of claim 1 , wherein the front end of the lower inner sealing part and a top surface of the upper case have the same height.

5 . The secondary battery of claim 1 , wherein a top surface of the upper inner sealing part and a top surface of the cover part have the same height.

6 . The secondary battery of claim 2 , wherein the electrode assembly comprises a plurality of radical units having through-holes that gradually increase in size, and the plurality of radical units are stacked upward in order from the radical unit having the smallest size to the radical unit having the largest size, and
the upper inner sealing part is inserted into a space between an inner surface of the through-hole of the lowermost radical unit and an inner surface of the uppermost radical unit of the radical units.

7 . The secondary battery of claim 1 , wherein a connection part connecting ends of the lower case and the upper case, which correspond to each other, to each other is provided.

8 . The secondary battery of claim 7 , wherein a lower outer sealing part and an upper outer sealing part, which are sealed to each other, are disposed on remaining ends except for the ends of the lower case and the upper case, respectively.

9 . A method for manufacturing a secondary battery, the method comprising:
a step (a) of manufacturing an electrode assembly having a through-hole; a step (b) of manufacturing a battery case comprising a lower case and an upper case, which are folded with respect to an end, wherein the lower case comprises an accommodation part accommodating the electrode assembly and a lower inner sealing part inserted into the through-hole and having an insertion groove, and the upper case comprises a cover part finishing the accommodation part and an upper inner sealing part having a coupling hole to which a front end of the lower inner sealing part is coupled; a step (c) of inserting the electrode assembly between the lower case and the upper case; a step (d) of sealing the coupled portion between the lower inner sealing part and the upper inner sealing part; and a step (e) of forming cutting a bottom surface of the insertion groove of the lower inner sealing part and a surface of the upper inner sealing part, which are closely attached to each other, to form a through-type opening into which the through-hole is inserted.

10 . The method of claim 9 , wherein the upper inner sealing part has an inner sealing surface having the coupling hole to which the front end of the lower inner sealing part is coupled and a connection surface having an inner end coupled to a bottom surface of the inner sealing surface and an outer end connected to the cover part, and
an opening groove is defined between the inner sealing surface and the connection surface.

11 . The method of claim 10 , wherein, in the step (d), the lower inner sealing part disposed on the insertion groove and the inner sealing surface disposed on the opening groove are press-fitted at the same time to seal the lower inner sealing part and the upper inner sealing part.

12 . The method of claim 9 , wherein, in step (b), a connection part connecting the lower case to the upper case is disposed on ends of the lower case and the upper case, which correspond to each other,
a lower outer sealing part and an upper outer sealing part, which are sealed to each other, are disposed on remaining ends except for the ends of the lower case and the upper case, respectively, and the step (d) further comprises a process of sealing the lower outer sealing part and the upper outer sealing part.

13 . The method of claim 9 , wherein the step (a) comprises a step of manufacturing a plurality of radical units having through-holes that gradually increase in size and a step of stacking the plurality of radical units upward in order from the radical unit having the smallest size to the radical unit having the largest size.

14 . A battery case comprising:
a lower case comprising an accommodation part and a lower inner sealing part provided at a center of the accommodation part and having a through-type opening; and an upper case comprising a cover part coupled to an upper portion of the lower case to finish the accommodation part and an upper inner sealing part having a coupling hole to which a front end of the lower inner sealing part is coupled.

15 . The battery case of claim 14 , wherein the upper inner sealing part has an inner sealing surface having the coupling hole to which the front end of the lower inner sealing part is coupled and a connection surface having an inner end coupled to a bottom surface of the inner sealing surface and an outer end connected to the cover part, and
an opening groove is defined between the inner sealing surface and the connection surface.

16 . The battery case of claim 15 , wherein the lower inner sealing part disposed on the through-type opening and the inner sealing surface disposed on the opening groove are press-fitted at the same time to seal the lower inner sealing part and the upper inner sealing part.

17 . The battery case of claim 14 , wherein the lower case and the upper case comprise a connection part connecting ends of the lower case and the upper case, which correspond to each other, to each other and a lower outer sealing part and an upper outer sealing part, which are sealed to each other and respectively disposed on remaining ends except for the ends of the lower case and the upper case.

Assignees

• Lg Chemical Ltd

Inventors

• Ko Joon Sang
• Ahn Chang Bum
• Yang Young Joo

Classifications

• H01M2004/025

  with shapes other than plane or cylindrical · CPC title

• H01M2220/00

  Batteries for particular applications · CPC title

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• H01M50/105

  Pouches or flexible bags · CPC title

• H01M50/186 Primary

  characterised by the disposition of the sealing members · CPC title