WO2017105009A1

WO2017105009A1 - Battery case, secondary battery, and method for manufacturing same

Info

Publication number: WO2017105009A1
Application number: PCT/KR2016/013967
Authority: WO
Inventors: 고준상; 안창범; 양영주
Original assignee: 주식회사 엘지화학
Priority date: 2015-12-16
Filing date: 2016-11-30
Publication date: 2017-06-22

Abstract

The present invention relates to a secondary battery comprising: an electrode assembly having a penetrator formed thereon; and a battery case for containing the electrode assembly, a penetration-type opening being formed on the battery case such that the penetrator is inserted therein, wherein the battery case comprises: a lower case having a containing portion for containing the electrode assembly and a lower inner sealing portion inserted into the penetrator, a penetration-type opening being formed on the lower inner sealing portion such that the penetrator is inserted therein; and an upper case having a cover portion coupled to the upper portion of the lower case, thereby finishing the containing portion, and an upper inner sealing portion having a coupling hole formed therein such that the front end of the lower inner sealing portion is coupled thereto.

Description

Battery Case, Secondary Battery and Manufacturing Method Thereof

Citation with Related Applications

This application claims the benefit of priority based on Korean Patent Application No. 2015-0180248 dated December 16, 2015 and Korean Patent Application No. 2016-0157558 dated November 24, 2016. The contents are included as part of this specification.

Technical Field

The present invention relates to a battery case, a secondary battery, and a method for manufacturing the same, and more particularly, to a battery case, a secondary battery, and a method for manufacturing the same to maximize the space utilization of the opening.

Generally, a secondary battery refers to a battery that can be charged and discharged, unlike a primary battery that cannot be charged. Such a secondary battery is widely used in advanced electronic devices such as phones, notebook computers, and camcorders.

On the other hand, recently, the secondary battery which has opening which penetrates up and down in the center part is disclosed.

The secondary battery includes an electrode assembly having a through hole formed up and down, and a pouch case accommodating the electrode assembly and having an opening formed therethrough.

Here, the pouch case includes an outer sealing surface for sealing the outer edge and an inner sealing surface for sealing the main surface of the opening, and the outer sealing surface and the inner sealing surface are sealed by applying heat while pressing the upper and lower surfaces simultaneously. .

However, in the secondary battery, since the outer sealing surface and the inner sealing surface are formed in the opening, the space of the opening is greatly reduced, and thus the space utilization of the opening is greatly reduced.

The present invention has been invented to solve the above problems, an object of the present invention is to improve the structure of the pouch case with the opening to prevent the space of the opening is reduced, thereby maximizing the space utilization of the battery It is to provide a case, a secondary battery and a method of manufacturing the same.

A secondary battery according to an embodiment of the present invention for achieving the above object is an electrode assembly formed with a through hole; And a battery case accommodating the electrode assembly and having a through type opening inserted into the through hole, wherein the battery case includes a receiving part accommodating the electrode assembly and a through type opening inserted into the through hole. A lower case having a lower inner sealing part formed thereon; And an upper case coupled to an upper portion of the lower case and having a cover portion closing the receiving portion and an upper inner sealing portion formed with a coupling hole to which the distal end of the lower inner sealing portion is coupled.

The upper inner sealing part, the inner sealing surface is formed with a coupling hole is coupled to the front end of the lower inner sealing portion, the inner end is provided with a connecting surface connected to the bottom surface of the inner sealing surface and the outer end is connected to the cover portion An open groove may be formed between the inner sealing surface and the connection surface.

The lower inner sealing part and the upper inner sealing part may be sealed by press-fitting the lower inner sealing part and the inner sealing surface located in the opening groove at the same time.

The front end of the lower inner sealing part may have the same height as the upper surface of the upper case.

An upper surface of the upper inner sealing part and an upper surface of the cover part may have the same height.

The electrode assembly is provided with a plurality of basic units formed with a through hole gradually increasing in size, the plurality of basic units are stacked in the order in order of the size of the through holes in the lower, the upper inner sealing portion of the lower basic of the basic unit It may be inserted into the space between the inner surface of the through hole of the unit and the inner surface of the through hole of the uppermost basic unit.

Connection portions connecting one end of the lower case and the upper case to each other may be formed.

A lower outer sealing part and an upper outer sealing part which are mutually sealed may be formed at the remaining ends except for one end of the lower case and the upper case, respectively.

On the other hand, the secondary battery manufacturing method according to an embodiment of the present invention comprises the steps of (a) manufacturing an electrode assembly having a through-hole; (b) manufacturing a battery case having a lower case and an upper case folded around one end, wherein the lower case is a receiving portion in which the electrode assembly is accommodated, and a lower inner sealing portion inserted into the through hole and formed with an insertion groove; It is provided, wherein the upper case is provided with a cover portion for closing the receiving portion, and the upper inner sealing portion formed with a coupling hole is coupled to the front end of the lower inner sealing portion; (c) inserting the electrode assembly between the lower case and the upper case; (d) sealing a coupling portion of the lower inner sealing portion and the upper inner sealing portion; And (e) cutting the bottom surface of the insertion grooves of the lower inner sealing part and the surface of the upper inner sealing part which are in close contact with each other to form a through type opening through which the through hole is inserted.

In the step (d), the lower inner sealing part and the upper inner sealing part may be sealed by press-fitting the lower inner sealing part and the inner sealing surface located in the opening groove at the same time.

In the step (b), one end of the lower case and the upper case corresponding to each other is formed a connecting portion for connecting the lower case and the upper case, the other end except the one end of the lower case and the upper case The lower outer sealing part and the upper outer sealing part which are mutually sealed are respectively formed, and the step (d) may further include sealing the lower outer sealing part and the upper outer sealing part.

The step (a) may include preparing a plurality of basic units in which the size of the through holes is gradually increased, and stacking the plurality of basic units on the bottom in an order of decreasing diameter of the through holes of the basic units.

On the other hand, the battery case according to an embodiment of the present invention includes a lower case having a receiving portion, and a lower inner sealing portion provided in the center of the receiving portion and the through-hole is formed; And an upper case coupled to an upper portion of the lower case and having a cover portion closing the receiving portion and an upper inner sealing portion formed with a coupling hole to which the distal end of the lower inner sealing portion is coupled.

The lower case and the upper case are connected to one end of the lower case and the upper case corresponding to each other, and the lower outer sealing portion formed at the other end of the lower case and the upper case except the connecting portion and sealed to each other And an upper outer sealing part may be respectively formed.

The secondary battery of the present invention includes a battery case having a vertical through-vertical opening formed therein, thereby greatly securing a space of the through-type opening, and improving space utilization.

In addition, the secondary battery of the present invention includes a battery case provided with a lower case and an upper case, wherein the lower case forms a lower inner sealing part having a through-type opening, and the upper case is an upper inner side into which the lower inner sealing part is inserted and coupled. By forming the sealing portion, it is possible to secure a large space of the through opening.

In addition, in the battery case according to the present invention, the front end of the lower inner sealing part and the upper surface of the upper case may be formed at the same height to prevent the thickness of the secondary battery from increasing.

In addition, in the battery case according to the present invention, the upper inner sealing part may be formed as the inner sealing surface and the connecting surface, so that the lower inner sealing part and the upper inner sealing part may be more easily sealed.

1 is a perspective view showing a secondary battery according to an embodiment of the present invention.

2 is a cross-sectional view taken along the line A-A shown in FIG.

3 is a cross-sectional view taken along the line B-B shown in FIG.

4 is a flowchart illustrating a method of manufacturing a secondary battery according to an embodiment of the present invention.

5 to 9 are working diagrams illustrating a method of manufacturing a secondary battery according to an embodiment of the present invention. FIG. 5 is a view showing a step of manufacturing an electrode assembly, and FIG. 6 shows a step of manufacturing a battery case. 7 is a view showing the step of inserting the electrode assembly into the battery case, Figure 8 is a view showing the step of sealing the battery case, Figure 9 is a view showing the step of forming a through-type opening.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

[일실시예에 따른 이차전지][Secondary Battery According to One Embodiment]

As shown in FIGS. 1 to 3, the secondary battery 100 according to an embodiment of the present invention accommodates the electrode assembly 110 and the electrode assembly 110 having the through holes formed therein, and the through holes are inserted therein. It includes a battery case 120 is formed through the opening.

전극조립체Electrode Assembly

Referring to FIG. 2, the electrode assembly 110 includes a plurality of basic units 111 stacked in the vertical direction, and the plurality of basic units 111 has a structure in which a plurality of electrodes and a plurality of separators are alternately stacked. Has

Herein, the electrode assembly 110 has a through hole 110a penetrating in the direction in which the basic units 111 are stacked. That is, the through holes formed in the plurality of basic units 111 are stacked to be connected in the vertical direction to form the electrode assembly 110 having the through holes 110a formed therein.

Meanwhile, the through holes formed in the plurality of basic units 111 are provided to have different sizes, that is, larger in size. That is, the basic unit 111 is stacked in the order from the smallest through-hole size to the bottom, the electrode assembly 110 can form a through-hole (110a) of approximately stepped inverted trapezoid cross-sectional shape. .

전지케이스Battery case

The battery case 120 is for accommodating the electrode assembly 110 to be hermetically sealed. The battery case 120 is provided on the upper and lower surfaces of the electrode assembly 110 and is coupled to each other, and the lower case 121 and the upper portion accommodate the electrode assembly 110. The case 122 is provided. Here, the battery case 120 has a through-hole opening 120a through which the through hole 110a is inserted.

The lower case 121 is a lower inner sealing part 121b having a receiving part 121a in which the electrode assembly 110 is accommodated, and a through type opening 120a provided in the center of the receiving part 121a and into which the through hole is inserted. Is prepared.

Here, the lower inner sealing part 121b extends in the same direction as the through direction of the through hole 110a to form a vertical through opening 120a, and the inner circumferential surface 121a-1 of the through opening 120a is a vertical plane. While forming a large space can be secured.

In addition, the front end of the lower inner sealing part 121b extends to the upper surface of the through hole 110a, that is, to have the same height as the upper case 122, thereby ensuring maximum space in the vertical opening of the through opening 120a. can do.

The upper case 122 is coupled to the upper surface of the lower case 121, and is coupled to the upper portion of the lower case 121 while being inserted into the cover part 122a for closing the receiving portion 121a and the through hole 110a. And an upper inner sealing part 122b in which a coupling hole 122b-1 to which the front end of the lower inner sealing part 121b is coupled is formed. That is, the upper inner sealing part 122b has a lower inner sealing part 121b. It is provided with a coupling hole (122b-1) for coupling, thereby improving the bondability of the upper inner sealing portion (122b) and the lower inner sealing portion (121b).

On the other hand, the upper inner sealing portion 122b is formed to extend downward from the cover portion 122a, at which time space is required to press-fit the heat sealing by pressing the lower inner sealing portion 121b and the upper inner sealing portion 122b Do. Here, the lower inner sealing part 121b may be press-fitted in the direction of the upper inner sealing part 122b through the opening 120a, but the upper inner sealing part 122b may not be press-fitting in the direction of the lower inner sealing part 121b. There is this.

Thus, the upper inner sealing part 122b has a form in which the sealing operation is possible by pressing in the direction of the lower inner sealing part 121b. For example, the upper inner sealing part 122b is provided in a 'U' or 'V' cross-sectional shape from the cover part 122a to form an open groove 122c that is open upward, and the open groove 122c is provided. The upper inner sealing part 122b may be press-fitted in the direction of the lower inner sealing part 121b to seal.

In more detail, the upper inner sealing portion 122b includes an inner sealing surface 122b-2 in which a coupling hole 122b-1 to which the front end of the lower inner sealing portion 121b is coupled is formed, and the inner end thereof is an inner sealing. It is connected to the bottom of the surface (122b-2) and the outer end is provided with a connecting surface (122b-3) is folded to the top and connected to the cover portion (122a).

That is, the upper inner sealing portion 122b is provided with the inner sealing surface 122b-2 and the connecting surface 122b-3, and forms an opening groove 122c therebetween, and an inner sealing located in the opening groove 122c. The surface 122b-2 may be press-fitted in the direction of the lower inner sealing part 121b to seal the surface 122b-2.

On the other hand, the upper inner sealing portion 122b provided with the inner sealing surface 122b-2 and the connecting surface 122b-3 is formed to protrude downward, and the lower inner sealing portion 122b protruding downward is the electrode assembly. It is inserted into the space between the inner surface of the through hole of the lowermost basic unit 111 of 110 and the inner surface of the through hole of the uppermost basic unit 111. Accordingly, the upper inner sealing part 122b may be formed without changing the shape of the electrode assembly 110 or the shape of the battery case 120.

The battery case 120 having the above configuration may form a through type opening 120a inserted into the through hole 110a of the electrode assembly 110. In particular, the through type opening 120a may have a main surface 121b-1. ) There is no protruding or raised part in the) so that the space can be secured greatly and the space utilization can be increased.

Meanwhile, the battery case 120 includes a connection part 123 connecting one end of the lower case 121 and the upper case 122. That is, the battery case 120 may be arranged to correspond to the upper case 122 and the lower case 121 by folding the upper case 122 in the direction of the lower case 121 with respect to the connecting portion 123.

Meanwhile, as illustrated in FIG. 3, the battery case 120 includes a lower outer sealing part 121c and an upper outer sealing part which are mutually sealed at the other ends except for one end of the lower case 121 and the upper case 122. 122d is formed, and thus the sealing force of the lower case 121 and the upper case 122 may be increased.

On the other hand, the upper surface of the upper inner sealing portion (122b) and the upper surface of the cover portion (122a) has the same height, thereby preventing the increase in the thickness of the battery case 120.

Therefore, the secondary battery 100 according to the embodiment of the present invention can secure a large space of the through-hole opening 120a formed in the battery case 120, and can improve the space utilization.

On the other hand, the secondary battery 100 according to an embodiment of the present invention can be commercialized as a separate product only the battery case 120.

[일실시예에 따른 전지케이스][Battery case according to one embodiment]

That is, the battery case 120 according to the embodiment of the present invention includes a receiving part 121a and a lower inner sealing part 121b provided at the center of the receiving part 121a and having a through-hole opening 120a formed therein. A coupling hole 122b- which is coupled to an upper portion of the lower case 121 and the lower case 121 and closes the receiving portion 121a and the tip of the lower inner sealing portion 121b is coupled. It includes an upper case 122 having an upper inner sealing portion (122b) is formed 1).

[일실시예에 따른 이차전지의 제조방법][Method of Manufacturing Secondary Battery According to One Embodiment]

Hereinafter, a method of manufacturing a secondary battery according to an embodiment of the present invention will be described.

Method of manufacturing a secondary battery according to an embodiment of the present invention, as shown in Figures 4 to 9, (a) manufacturing an electrode assembly having a through hole, (b) a lower case folded around one end And a battery case provided with an upper case, wherein the lower case is provided with an accommodating portion accommodating the electrode assembly and a lower inner sealing portion inserted into the through hole and formed with an insertion groove, and the upper case is closed with the accommodating portion. Comprising a cover portion and the upper inner sealing portion is formed with a coupling hole is coupled to the front end of the lower inner sealing portion, (c) Inserting the electrode assembly between the lower case and the upper case, (d) The Sealing a coupling portion of the lower inner sealing portion and the upper inner sealing portion, and (e) the insertion groove and the upper inner portion of the lower inner sealing portion in close contact with each other. Cutting the surface of the sealing portion to form a through opening into which the through hole is inserted.

(a) 단계(a) step

Step (a) is for manufacturing an electrode assembly, as shown in FIG. 5, and includes a process of manufacturing a plurality of basic units and a process of stacking a plurality of basic units.

In the basic unit manufacturing process, a plurality of electrodes having through holes and a plurality of separators having through holes are alternately stacked to manufacture the basic unit 111. At this time, the through hole of the electrode is connected to the through hole of the separator is formed in the basic unit 111 is formed.

On the other hand, the basic unit manufacturing process produces a plurality of basic unit 111, the size of the through hole is gradually increased.

In the basic unit stacking process, a plurality of basic units 111 are stacked to manufacture an electrode assembly 110. In this case, the plurality of basic units 111 are stacked on top of each other in the order of the size of the through-holes from the smallest to the largest ones, and the through-holes 110a are formed in the electrode assembly 110 gradually increasing in size from the bottom to the top. That is, the through hole 110a has a shape in which the size gradually increases from the bottom to the top with reference to FIG. 5.

(b) 단계(b) step

Step (b) is for manufacturing a battery case, as shown in Figure 6, the battery case 120 is provided with a lower case 121 and the upper case 122, one end of which is connected by a connecting portion 123. To prepare.

That is, the battery case 120 is folded to overlap the center of one end connected the lower case 121 and the upper case 122.

Here, the lower case 121 is formed on the receiving portion 121a having a receiving space in which the electrode assembly 110 is accommodated on the upper surface, and a surface of the receiving portion 121a (bottom surface when viewed in FIG. 6) and having a through hole ( It is provided with a lower inner sealing portion 121b extending upward to be inserted into 110a) and having an insertion groove open downward.

The upper case 122 has a cover portion 122a closing the receiving portion 121a and an upper inner sealing portion 122b in which a coupling hole 122b-1 through which the tip of the lower inner sealing portion 121b is coupled is formed. Is provided.

Here, the upper inner sealing portion 122b includes an inner sealing surface 122b-2 in which a coupling hole 122b-1 to which the distal end of the lower inner sealing portion 121b is coupled is formed, and the inner end thereof is an inner sealing surface 122b. It is connected to the bottom of the (2) and the outer end is provided with a connecting surface (122b-3) connected to the cover portion (122a), the opening groove between the inner sealing surface (122b-2) and the connecting surface (122b-3) 122c is formed.

The lower outer sealing part 121c and the upper outer sealing part 122d are formed at the remaining ends except for one end of the lower case 121 and the upper case 122, respectively.

(c) 단계(c) step

Step (c) is to insert the electrode assembly into the battery case, as shown in Figure 7, the electrode assembly 110 is inserted into the receiving portion 121a of the lower case 121. In this case, the lower inner sealing part 121b of the lower case 121 is inserted into the through hole 110a of the electrode assembly 110 and then coupled to the coupling hole 121b-1 of the upper case 122.

(d) 단계(d) step

Step (d) is to seal the battery case, as shown in Figure 8, the upper heat sealing member 320 in the open groove 122c of the upper inner sealing portion 122b, and the lower inner sealing The lower heat seal member 310 is disposed in the insertion groove of the portion 121 b, and then heat is applied to the lower heat seal member 310 toward the lower heat seal member 310 to apply the heat to the lower inner seal part 121 b. ) And the upper inner sealing part 122b.

Then, heat is applied while sealing the lower outer sealing part 121c and the upper outer sealing part 122d.

(e) 단계(e) step

Step (e) is to form a through-hole opening into which the through hole is inserted, as shown in FIG. 9, and cuts the bottom surface of the insertion groove of the lower inner sealing part 121b, and the through hole 110a. The secondary battery 100 is completed while the through-hole opening 120a is inserted.

Therefore, in the method of manufacturing a secondary battery according to an embodiment of the present invention, a secondary battery having a through type opening is manufactured, but a space of the through type opening can be largely secured, thereby increasing space utilization.

The scope of the present invention is shown by the following claims rather than the detailed description, and various embodiments derived from the meaning and scope of the claims and their equivalents are possible.

Claims

An electrode assembly having a through hole formed therein; And

A battery case accommodating the electrode assembly and having a through-type opening inserted into the through-hole;

The battery case,

A lower case including a receiving part accommodating the electrode assembly and a lower inner sealing part in which a through type opening inserted into the through hole is formed; And

And an upper case having a cover portion coupled to an upper portion of the lower case and closing the receiving portion, and an upper inner sealing portion formed with a coupling hole to which the distal end of the lower inner sealing portion is coupled.
The method according to claim 1,

The upper inner sealing portion,

The inner sealing surface is formed with a coupling hole is coupled to the front end of the lower inner sealing portion, the inner end is provided with a connecting surface connected to the bottom surface of the inner sealing surface and the outer end is connected to the cover portion,

Secondary battery, characterized in that the opening groove is formed between the inner sealing surface and the connecting surface.
The method according to claim 2,

And the lower inner sealing part and the upper inner sealing part are simultaneously press-fitted into the lower inner sealing part and the inner sealing surface located in the opening groove.
The method according to claim 1,

The front end of the lower inner sealing portion has a secondary battery, characterized in that the same height as the upper surface of the upper case.
The method according to claim 1,

A secondary battery, wherein the upper surface of the upper inner sealing part and the upper surface of the cover part have the same height.
The method according to claim 2,

The electrode assembly is provided with a plurality of basic units formed with a through hole is gradually increasing in size, the plurality of basic units are stacked on the bottom in the order of the small size of the through hole,

And the upper inner sealing part is inserted into a space between an inner surface of a through hole of a lowermost basic unit of the basic unit and an inner surface of a through hole of an uppermost basic unit.
The method according to claim 1,

Secondary battery, characterized in that the connecting portion for connecting one end of the lower case and the upper case corresponding to each other is formed.
The method according to claim 7,

A secondary battery, wherein the lower outer sealing part and the upper outer sealing part are formed at the remaining ends except for one end of the lower case and the upper case, respectively.
(a) manufacturing an electrode assembly having a through hole formed therein;

(b) manufacturing a battery case having a lower case and an upper case folded around one end, wherein the lower case is a receiving portion in which the electrode assembly is accommodated, and a lower inner sealing portion inserted into the through hole and formed with an insertion groove; It is provided, wherein the upper case is provided with a cover portion for closing the receiving portion, and the upper inner sealing portion formed with a coupling hole is coupled to the front end of the lower inner sealing portion;

(c) inserting the electrode assembly between the lower case and the upper case;

(d) sealing a coupling portion of the lower inner sealing portion and the upper inner sealing portion; And

(E) manufacturing a secondary battery comprising the step of forming a through-type opening through which the through hole is inserted by cutting the bottom surface of the insertion groove of the lower inner sealing portion and the upper inner sealing portion in close contact with each other. Way.
The method according to claim 9,

The upper inner sealing portion,

The inner sealing surface is formed with a coupling hole is coupled to the front end of the lower inner sealing portion, the inner end is provided with a connecting surface connected to the bottom surface of the inner sealing surface and the outer end is connected to the cover portion,

An open groove is formed between the inner sealing surface and the connection surface.
The method according to claim 10,

In the step (d), the lower inner sealing part and the upper inner sealing part are simultaneously sealed by press-fitting the lower inner sealing part and the inner sealing surface located in the opening groove. Manufacturing method.
The method according to claim 9,

In the step (b), one end of the lower case and the upper case corresponding to each other is formed a connecting portion for connecting the lower case and the upper case,

The lower outer sealing part and the upper outer sealing part which are mutually sealed are formed at the remaining ends except for one end of the lower case and the upper case, respectively.

The step (d) of the secondary battery manufacturing method characterized in that it further comprises the step of sealing the lower outer sealing portion and the upper outer sealing portion.
The method according to claim 9,

The step (a) comprises the steps of manufacturing a plurality of basic units in which the size of the through-hole gradually increases, and laminating a plurality of basic units on the bottom in the order of the diameter of the through-holes of the basic unit in the order of smallest Method of manufacturing a secondary battery.
A lower case having a receiving portion and a lower inner sealing portion provided in the center of the receiving portion and having a through opening formed therein; And

And an upper case having a cover portion coupled to an upper portion of the lower case and closing the receiving portion, and an upper inner sealing portion formed with a coupling hole to which the distal end of the lower inner sealing portion is coupled.
The method according to claim 14,

The upper inner sealing portion,

The inner sealing surface is formed with a coupling hole is coupled to the front end of the lower inner sealing portion, the inner end is provided with a connecting surface connected to the bottom surface of the inner sealing surface and the outer end is connected to the cover portion,

The battery case, characterized in that the opening groove is formed between the inner sealing surface and the connecting surface.
The method according to claim 15,

And the lower inner sealing part and the upper inner sealing part are simultaneously press-fitted into the lower inner sealing part and the inner sealing surface located in the opening groove.
The method according to claim 14,

The lower case and the upper case are connected to one end of the lower case and the upper case corresponding to each other, and the lower outer sealing portion formed at the other end of the lower case and the upper case except the connecting portion and sealed to each other And an upper outer sealing part, respectively.