U.S. patent application number 13/403261 was filed with the patent office on 2013-05-16 for battery cell and battery module including the same.
This patent application is currently assigned to SK INNOVATION CO., LTD.. The applicant listed for this patent is SANG BUM KIM, HEECHAN PARK. Invention is credited to SANG BUM KIM, HEECHAN PARK.
Application Number | 20130122335 13/403261 |
Document ID | / |
Family ID | 48280945 |
Filed Date | 2013-05-16 |
United States Patent
Application |
20130122335 |
Kind Code |
A1 |
PARK; HEECHAN ; et
al. |
May 16, 2013 |
BATTERY CELL AND BATTERY MODULE INCLUDING THE SAME
Abstract
Provided are a battery cell and a battery module including the
same. The battery cell is provided with a vent part, which is a
predetermined region of a sealing part of a case having a width
narrower than that of the other region thereof, thereby making it
possible to easily discharge gas.
Inventors: |
PARK; HEECHAN; (Daejeon,
KR) ; KIM; SANG BUM; (Seoul, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PARK; HEECHAN
KIM; SANG BUM |
Daejeon
Seoul |
|
KR
KR |
|
|
Assignee: |
SK INNOVATION CO., LTD.
Seoul
KR
|
Family ID: |
48280945 |
Appl. No.: |
13/403261 |
Filed: |
February 23, 2012 |
Current U.S.
Class: |
429/82 ;
29/623.2 |
Current CPC
Class: |
Y10T 29/4911 20150115;
H01M 2/1241 20130101; H01M 2/0212 20130101; H01M 10/052 20130101;
H01M 2/1061 20130101; H01M 10/0436 20130101; Y02E 60/10
20130101 |
Class at
Publication: |
429/82 ;
29/623.2 |
International
Class: |
H01M 2/12 20060101
H01M002/12; H01M 2/08 20060101 H01M002/08 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 14, 2011 |
KR |
10-2011-0118226 |
Claims
1. A battery cell comprising: a battery unit including a first
electrode part, a second electrode part, and a separator; first and
second electrode taps each welded to the first and second electrode
parts; and a case having the first and second electrode taps
protruded outwardly thereof, having a pouch form in which it is
sealed while including the first electrode part, the second
electrode part, and the separator in an inner portion thereof, and
including a sealing part having a sealing member applied thereto
and a vent part, which is a predetermined region of the sealing
part having a width narrower than that of the other region
thereof.
2. The battery cell of claim 1, wherein the sealing part of the
case is heat-fused and bonded by a pair of compression parts each
provided with first and second grooves having a shape corresponding
to that of the vent part.
3. A battery module formed by stacking the battery cell of claim 2
in plural.
4. The battery cell of claim 1, wherein the vent part is formed so
that a predetermined region from an inner side of the case to an
outer side thereof is not bonded.
5. The battery cell of claim 4, wherein the sealing part of the
case is heat-fused and bonded by a pair of compression parts each
provided with first and second grooves having a shape corresponding
to that of the vent part.
6. A battery module formed by stacking the battery cell of claim 5
in plural.
7. A method of manufacturing a battery cell, the method comprising:
a manufacturing step of manufacturing a battery part including a
first electrode part, a second electrode part, and a separator and
welding each of first and second electrode taps to the first and
second electrode parts; a receiving step of receiving a battery
part in a case so that in which the first and second electrode taps
are protruded outwardly; and a sealing step of heat-fusing and
bonding a sealing part to which a sealing member is applied in the
case to each other by a pair of compression parts provided with
first and second grooves.
8. The method of claim 7, wherein the sealing step includes: a
disposing step of disposing each of the pair of compression parts
at upper and lower sides of the sealing part so that the first and
second grooves face each other; and a heat-fusing step of
heat-fusing a portion at which the pair of compression parts
contacts the sealing part to form a vent part, which is a
predetermined region of the sealing part having a bonding width
narrower than that of the other region thereof.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. .sctn.119
to Korean Patent Application No. 10-2011-0118226, filed on Nov. 14,
2011, the disclosure of which is incorporated herein by reference
in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to a battery cell for directly
converting chemical energy into electrical energy and a battery
module including the same, and more particularly, to a battery cell
capable of easily discharging gas in a battery, and a battery
module including the same.
BACKGROUND
[0003] Recently, as miniaturization and lightness of portable
electronic devices have rapidly progressed, the necessity for
miniaturization of a battery and an increase in capacity of the
battery used as a driving power supply of the portable electronic
devices has increased. Among others, a lithium secondary battery
has an operation voltage of 3.6 V or more, which is three times
higher than that of a nickel-cadmium battery or a nickel-hydrogen
battery mainly used as a power supply of the portable electronic
devices, and has high energy density per unit weight, such that the
use of the lithium secondary battery has been rapidly extended.
[0004] The lithium secondary battery is mainly divided into a
cylindrical battery, a square type battery, a pouch type battery,
and the like, according to an appearance thereof, and is divided
into a lithium ion battery, a lithium ion polymer battery, a
lithium polymer battery, and the like, according to a form of an
electrolyte solution.
[0005] Among them, the demand for the square type battery and the
pouch type battery having a thin thickness has increased in
accordance with the trend toward miniaturization of a mobile
device. Particularly, the interest in the pouch type battery having
an easily changed form, a low manufacturing cost, and light weight
has increased.
[0006] Generally, the pouch type battery means a battery in which
an electrode assembly and an electrolyte are sealed in a pouch type
case of a laminate sheet configured to include a resin layer and a
metal layer. The electrode assembly received in the case has a
jelly roll type (winding type) structure or a stack type
structure.
[0007] Meanwhile, in the pouch type secondary battery, operation
potential of the battery is high, such that high energy may
instantaneously flow, and cathode materials have chemical activity
significantly increased due to overcharge or a short-circuit to
rapidly react with an electrolyte, thereby generating a large
amount of gas. As a result, the battery explodes due to a rapid
increase in pressure or temperature in the battery, such that
peripheral devices or a human body may be damaged.
[0008] Particularly, this problem may cause a more series large
accident in the case of a middle or large-sized battery pack
including a plurality of battery cells.
[0009] Since the middle or large-sized battery pack includes a
plurality of battery cells or unit modules in a frame having a
predetermined space, as the plurality of battery cells or unit
modules are expanded, pressure in a case may be rapidly
increased.
[0010] Due to the above-mentioned reason, an attempt to solve a
stability problem of the secondary battery module has been
continuously conducted. However, in most cases, a method of
attaching a separate component or device is used, such that an
additional process or equipment is required at the time of
producing the battery, thereby decreasing productivity and energy
density of the battery and increasing a production cost of the
battery.
[0011] A battery cell disclosed in Korean Patent Laid-Open
Publication No. 2004-0081521 is configured to include a case
receiving a jelly-roll type (winding type) electrode assembly.
[0012] The battery cell according to the related art further
includes a safety plate depressed from an outer side of the case to
an inner side thereof.
[0013] In order to solve a problem that the battery explodes due to
an increase in internal pressure or temperature, the battery cell
according to the related art is provided with the safety plate
broken at the time of an increase in the pressure to thereby be
used as a path through which gas is discharged.
[0014] However, in the battery cell according to the related art,
when the internal pressure increases, since a sealed portion of the
case is first opened and the safety plate is then broken while
stress is transferred up to a position at which the safety plate is
formed, threshold internal pressure at which the safety plate is
broken may not be controlled.
[0015] In addition, in the battery cell according to the related
art, since the threshold internal pressure at which the safety
plate is broken may not be concentrated, the battery cell may
explode without break of the safety plate even in a state in which
the safety plate does not withstand the internal pressure.
[0016] Therefore, the development of a technology capable of
controlling pressure at which a case of a battery cell may be
securely broken has been demanded.
RELATED ART DOCUMENT
Patent Document
[0017] Korean Patent Laid-Open Publication No. 2004-0081521(Sep.
22, 2004)
SUMMARY
[0018] An embodiment of the present invention is directed to
providing a battery cell capable of preventing a battery from
exploding due to a rapid increase in internal pressure or
temperature in the battery by forming a portion at which the
internal pressure of the battery cell is concentrated, and a
battery module including the same.
[0019] In one general aspect, a battery cell includes: a battery
unit including a first electrode part, a second electrode part, and
a separator; first and second electrode taps each welded to the
first and second electrode parts; and a case having the first and
second electrode taps protruded outwardly thereof, having a pouch
form in which it is sealed while including the first electrode
part, the second electrode part, and the separator in an inner
portion thereof, and including a sealing part having a sealing
member applied thereto and a vent part, which is a predetermined
region of the sealing part having a width narrower than that of the
other region thereof.
[0020] The sealing part of the case may be heat-fused and bonded by
a pair of compression parts each provided with first and second
grooves having a shape corresponding to that of the vent part.
[0021] In another general aspect, a battery module is formed by
stacking the battery cell as described above in plural.
[0022] The vent part may be formed so that a predetermined region
from an inner side of the case to an outer side thereof is not
bonded.
[0023] The sealing part of the case may be heat-fused and bonded by
a pair of compression parts each provided with first and second
grooves having a shape corresponding to that of the vent part.
[0024] In still another general aspect, a battery module is formed
by stacking the battery cell as described above in plural.
[0025] In still another general aspect, a method of manufacturing a
battery cell includes: a manufacturing step of manufacturing a
battery part including a first electrode part, a second electrode
part, and a separator and welding each of first and second
electrode taps to the first and second electrode parts; a receiving
step of receiving a battery part in a case so that in which the
first and second electrode taps are protruded outwardly; and a
sealing step of heat-fusing and bonding a sealing part to which a
sealing member is applied in the case to each other by a pair of
compression parts provided with first and second grooves.
[0026] The sealing step may include: a disposing step of disposing
each of the pair of compression parts at upper and lower sides of
the sealing part so that the first and second grooves face each
other; and a heat-fusing step of heat-fusing a portion at which the
pair of compression parts contacts the sealing part to form a vent
part, which is a predetermined region of the sealing part having a
bonding width narrower than that of the other region thereof.
[0027] Other features and aspects will be apparent from the
following detailed description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a perspective view of a battery cell according to
an exemplary embodiment of the present invention.
[0029] FIGS. 2A and 2D are perspective views showing a method of
manufacturing a battery cell according to an exemplary embodiment
of the present invention.
[0030] FIGS. 3A to 3G are views of several examples of a vent part
according to an exemplary embodiment of the present invention.
[0031] FIG. 4 is a graph showing stress concentration by a
formation area of a vent part according to an exemplary embodiment
of the present invention.
TABLE-US-00001 [Detailed Description of Main Elements] 1000:
Battery Cell 100: Battery Part 110: First Electrode Part 120:
Second Electrode Part 130: Separator 200: First Electrode Tap 300:
Second Electrode Tap 400: Case 410: Sealing Part 420: Vent part
500: Pair of Compression Part 510: First Groove 520: Second Groove
L410: Width of Sealing Part L420: Width of Vent part
DETAILED DESCRIPTION OF EMBODIMENTS
[0032] The advantages, features and aspects of the present
invention will become apparent from the following description of
the embodiments with reference to the accompanying drawings, which
is set forth hereinafter. The present invention may, however, be
embodied in different forms and should not be construed as limited
to the embodiments set forth herein. Rather, these embodiments are
provided so that this disclosure will be thorough and complete, and
will fully convey the scope of the present invention to those
skilled in the art. The terminology used herein is for the purpose
of describing particular embodiments only and is not intended to be
limiting of example embodiments. As used herein, the singular forms
"a," "an" and "the" are intended to include the plural forms as
well, unless the context clearly indicates otherwise. It will be
further understood that the terms "comprises" and/or "comprising,"
when used in this specification, specify the presence of stated
features, integers, steps, operations, elements, and/or components,
but do not preclude the presence or addition of one or more other
features, integers, steps, operations, elements, components, and/or
groups thereof.
[0033] Hereinafter, exemplary embodiments will be described in
detail with reference to the accompanying drawings.
[0034] Hereinafter, the technical spirit of the present invention
will be described in more detail with reference to the accompanying
drawings.
[0035] FIG. 1 is a perspective view of a battery cell according to
an exemplary embodiment of the present invention.
[0036] As shown in FIG. 1, the battery cell 1000 according to the
exemplary embodiment of the present invention is configured to
include a battery part 100, first and second electrode taps 200 and
300, and a case 400.
[0037] The battery part 100, which is a component provided in the
case 400, is configured to include a first electrode part 110, a
second electrode part 120, and a separator 130.
[0038] Here, the separator is provided between the first and second
electrode parts 110 and 120, and the first electrode part 110, the
second electrode part 120, and the separator 130 are provided,
together with an electrolyte solution, in the case 400.
[0039] Each of the first and second electrode taps 200 and 300,
which are components protruded outwardly of the case 400 so as to
be connected to power supply, is welded to the first and second
electrode parts 110 and 120.
[0040] The case 400, which is a basic body forming the battery cell
1000, is sealed in a pouch form and is configured to include a
sealing part 410 and a vent part 420.
[0041] The sealing part 410 is a predetermined region to which a
sealing member is applied in the case 400, and the case 400 is
bonded by applying the sealing member to the sealing part 410, such
that it is sealed in a pouch form.
[0042] Here, the sealing part 410 may be bonded by applying the
sealing member thereto or be bonded by heat-fusing the region in
which the sealing member is applied.
[0043] The vent part 420 is a region having a bonding width L420
narrower than a width L410 of the sealing part 410 region.
[0044] An enlarged view shown in FIG. 1 is a lateral
cross-sectional view of a region in which the vent part 420 is
formed. Referring to FIG. 1, the region in which the vent part 420
is formed has a width L420 narrower than the bonding width L410 of
a predetermined region of the sealing unit 410.
[0045] That is, the vent part 420, which is a region having the
bonding width L420 narrower than the bonding width L410 of the
sealing part 410, is formed so that a predetermined region from an
inner side of the case 400 to an outer side thereof is not
bonded.
[0046] In this case, when internal pressure of the case 400
increases due to overcharge of the battery and battery module,
overheat such as an internal short-circuit, or the like, stress is
concentrated on the vent part 420.
[0047] When the stress is concentrated on the vent part 420, the
case 400 is first opened at the inner side thereof based on the
region of the vent part 420.
[0048] Therefore, the battery cell 1000 according to the exemplary
embodiment of the present invention is provided with the vent part
420, which is a predetermined region having a bonding width L420
narrower than that of the other region in a bonding region of the
case 400, to prevent explosion or ignition of the battery due to a
rapid increase in internal pressure or temperature of the battery,
thereby making it possible to ensure stability.
[0049] FIGS. 2A and 2D are perspective views showing a method of
manufacturing a battery cell according to an exemplary embodiment
of the present invention.
[0050] As shown in FIG. 2, the method of manufacturing a battery
cell 1000 according to the exemplary embodiment of the present
invention includes the following operations.
[0051] First, as shown in FIG. 2A, a battery part 100 including a
first electrode part 110, a second electrode part 120, and a
separator 130 is manufactured, and each of first and second
electrode taps 200 and 300 is welded to the first and second
electrode parts 110 and 120. This operation corresponds to a
battery manufacturing operation.
[0052] Then, as shown in FIG. 2B, the battery part 100 is received
in a case 400 so that the first and second electrode taps 200 and
300 are protruded outwardly of the case 400. This operation
corresponds to a reception operation.
[0053] Next, as shown in FIGS. 2C to 2D, a sealing part 410 to
which a sealing member is applied in the case 400 is heat-fused and
bonded by a pair of compression parts 500 having first and second
grooves 510 and 520 formed in each of one surfaces thereof. This
operation corresponds to a sealing operation.
[0054] Here, the sealing operation may be divided into a disposing
operation and a heat-fusing operation, which will be described in
detail.
[0055] First, referring to FIG. 2C, one surfaces of the pair of
compression parts 500 in which the first and second grooves 510 and
520 are formed are disposed at upper and lower sides of the sealing
part 410 so as to face each other. This operation corresponds to a
disposition operation.
[0056] Next, referring to FIG. 2D, a portion at which the pair of
compression parts 500 contacts the sealing part 410 is heat-fused
to form a vent part 420, which is a predetermined region of the
sealing part 410 having a bonding width narrower than that of the
other region thereof. This operation corresponds to a heat fusing
operation.
[0057] Therefore, the battery cell 1000 according to the exemplary
embodiment of the present invention includes the vent part 420
formed in a simple scheme by heat-fusing the sealing part of the
case 400, such that it may be rapidly manufactured.
[0058] In addition, the battery module 1000 according to the
exemplary embodiment of the present invention is formed by stacking
a plurality of battery cells 1000.
[0059] FIGS. 3A to 3G are views of several examples of a vent part
according to an exemplary embodiment of the present invention.
[0060] Referring to FIGS. 3A to 3G showing several examples of a
vent part 420 based on a lateral cross section of a sealing part
410 in which the vent part 420 is formed, the vent part 420 is
formed in a predetermined region of the sealing part 410 and has
various shapes such as a triangular shape, a semicircular shape, a
rectangular shape, an oval shape, and a trapezoidal shape based on
a cross-sectional view taken along a side of the sealing part
410.
[0061] FIG. 4 is a graph showing stress concentration by a
formation area of a vent part in the battery cell according to an
exemplary embodiment of the present invention.
[0062] It may be appreciated from FIG. 4 that stress concentration
transferred to the vent part 420 of the battery cell 1000 according
to the exemplary embodiment of the present invention is changed
according to a shape and a formation area of the vent part 420.
[0063] It may be appreciated that the stress concentration does not
become high as the formation area of the vent part 420 increases,
but is high in a predetermined area.
[0064] Therefore, the battery cell 1000 according to the exemplary
embodiment of the present invention is provided with the vent part
420, which is a predetermined region having a bonding width
narrower than that of the other region in a bonding region of the
case 400, thereby making it possible to set pressure at which the
case is opened due to explosion or ignition of the battery caused
by a rapid increase in internal pressure or temperature of the
battery.
[0065] As described above, the battery cell according to the
exemplary embodiment of the present invention is provided with the
vent part, which is a predetermined region having a bonding width
narrower than that of the other region in a sealing region of the
case, to prevent explosion or ignition of the battery due to a
rapid increase in internal pressure or temperature of the battery,
thereby making it possible to ensure stability.
[0066] Therefore, the battery cell according to the exemplary
embodiment of the present invention includes the vent part formed
in a simple scheme by heat-fusing the sealing part of the case,
such that it may be rapidly manufactured.
[0067] In addition, the battery cell according to the exemplary
embodiment of the present invention is provided with the vent part,
which is a predetermined region having a bonding width narrower
than that of the other region in a bonding region of the case,
thereby making it possible to set pressure at which the case is
opened due to explosion or ignition of the battery caused by a
rapid increase in internal pressure or temperature of the
battery.
[0068] However, the accompanying drawings are only examples shown
in order to describe the technical idea of the present invention in
more detail. Therefore, the technical idea of the present invention
is not limited to shapes of the accompanying drawings.
[0069] The present invention is not limited to the above-mentioned
exemplary embodiments, and may be variously applied, and may be
variously modified without departing from the gist of the present
invention claimed in the claims.
* * * * *