Sealing device for pouch-type battery case and sealing method using same

Abstract

The present invention relates to a sealing device for sealing a sealing part of a battery case in which an electrode assembly is accommodated and a sealing method using same, the sealing device comprising a first sealing unit positioned at one side of the sealing part of the battery case, and a second sealing unit positioned at the other side of the sealing part of the battery case, wherein the first sealing unit includes: a first heating block which is heated to a predetermined temperature; a first support block in close contact with the first heating block; a first sealing tool positioned in close contact with one surface of the first support block so as to apply pressure to one surface of the sealing part; and a pair of first stopper units disposed on either end of the first support block to be rotatably coupled thereto and comprising contact surfaces inclined so as to have varying heights along the curved surfaces thereof.

Description

Sealing device for pouch-type battery case and sealing method using the same

[0001] This application claims the benefit of priority to Korean Patent Application No. 2024-0119671, filed September 4, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a sealing device for a pouch-type battery case and a sealing method using the same, and more specifically, to a sealing device for a pouch-type battery case and a sealing method using the same, wherein the height of a stopper can be adjusted so that the distance between a pair of sealing tools corresponds to the thickness of a sealing portion of a pouch-type battery case.

[0003]

[0004] As technological development and demand for mobile devices increase, rechargeable secondary batteries are increasingly being used as energy sources for a variety of mobile devices. Secondary batteries are also attracting attention as an energy source for electric and hybrid electric vehicles, offering an alternative to conventional gasoline and diesel vehicles that rely on fossil fuels.

[0005] Secondary batteries are classified into cylindrical and prismatic batteries, in which the electrode assembly is built into a cylindrical or prismatic metal can, and pouch-type batteries, in which the electrode assembly is built into a pouch-type case made of aluminum laminate sheet, depending on the shape of the battery case.

[0006] The typical pouch-type secondary battery manufacturing process involves inserting an electrode assembly into a battery case accommodating space made of a laminate sheet, injecting an electrolyte inside the battery case, and then performing a sealing process.

[0007] Figure 1 is a drawing showing a sealing device of a pouch-type battery case according to the prior art sealing a secondary battery.

[0008] Referring to Fig. 1, a sealing device for a conventional pouch-type battery case includes an upper jig (1) and a lower jig (2) positioned respectively above and below a sealing portion (S) of a battery case (12) that houses an electrode assembly (11). The upper jig (1) and the lower jig (2) move in opposite directions and seal the sealing portion (S) by applying a certain pressure and temperature.

[0009] At this time, there is a problem that the sealing part (S) of the pouch-type battery case (12) is heated and pressurized with the same pressure regardless of the thickness of the sealing part (S), so that the bonding of the sealing parts (S) with different thicknesses is not uniform, resulting in a deviation in quality.

[0010] To solve this problem, Korean Patent Publication No. 10-2024-0082572 discloses a top sealing device for a pouch-type battery cell, which inserts a shim ring between a pair of sealing blocks to adjust the gap between the pair of sealing blocks in order to adjust the thickness of the sealing portion (S).

[0011] However, there is the hassle of having to insert or remove the shim between a pair of sealing blocks each time the gap is adjusted according to the thickness of the sealing portion (S), which reduces the continuity and efficiency of the work.

[0012] In particular, there is a problem of high cost because shims with different heights must be provided to gradually adjust the gap between a pair of sealing blocks.

[0013]

[0014] (Prior art literature)

[0015] (Patent Document 1) Korean Patent Publication No. 10-2024-0082572

[0016]

[0017] In order to solve the above problems, the present invention aims to provide a sealing device for a pouch-type battery case and a sealing method using the same, which can easily adjust the gap between a pair of sealing tools to correspond to the thickness of the sealing portion of the pouch-type battery case.

[0018] In addition, the present invention aims to provide a sealing device for a pouch-type battery case and a sealing method using the same, which can minimize installation or maintenance costs of the device.

[0019]

[0020] In order to achieve the above object, a sealing device according to the present invention is a sealing device for sealing a sealing portion of a battery case in which an electrode assembly is accommodated, the sealing device comprises: a first sealing unit (100) positioned on one side of the sealing portion of the battery case; and a second sealing unit (200) positioned on the other side of the sealing portion of the battery case; wherein the first sealing unit (100) comprises: a first heating block (110) heated to a constant temperature; a first support block (120) in close contact with the first heating block (110); a first sealing tool (130) positioned in close contact with one surface of the first support block (120) so as to press one surface of the sealing portion; and a pair of first stopper portions (140) positioned on both sides of the first support block (120) so as to be rotatably coupled and having inclined contact surfaces (141) formed to have different heights along the circumference.

[0021] In addition, in the sealing device according to the present invention, the second sealing unit (200) includes a second stopper part (240) that is in close contact with the contact surface (141) of the first stopper part (140), and the contact surface (141) of the first stopper part (140) and the second stopper part (240) are characterized in that they are in line contact or point contact.

[0022] In addition, in the sealing device according to the present invention, the second sealing unit (200) is characterized by including a second heating block (210) heated to a constant temperature, a second support block (220) in close contact with the second heating block (210), a second sealing tool (230) positioned in close contact with one surface of the second support block (220) so as to press the other surface of the sealing portion, and a pair of second stopper parts (240) positioned on both sides of the second support block (220).

[0023] In addition, in the sealing device according to the present invention, the second stopper part (240) is characterized in that one end is shaped like a blade and has an inclined surface (241) so as to make linear contact with the contact surface (141) of the first stopper part (140).

[0024] In addition, in the sealing device according to the present invention, the second stopper part (240) is characterized in that one end is hemispherical so as to come into point contact with the contact surface (141) of the first stopper part (140).

[0025] In addition, in the sealing device according to the present invention, an insertion hole (142) is provided in the center of the contact surface (141) of the first stopper part (140), and a fastening member (143) for connecting the first support block (120) and the first stopper part (140) is accommodated in the insertion hole (142).

[0026] In addition, in the sealing device according to the present invention, the fastening member (143) is characterized by being a bolt.

[0027] In addition, in the sealing device according to the present invention, a packing member (144) is received in the insertion hole (142), and the fastening member (143) is fastened to the first support block (120) after penetrating the packing member (144).

[0028] In addition, in the sealing device according to the present invention, the packing member (144) is characterized in that it is made of an elastic material.

[0029] In addition, in the sealing device according to the present invention, the packing member (144) is characterized in that it includes a rubber or silicone material.

[0030] In addition, in the sealing device according to the present invention, the contact surface (141) is characterized in that a radial display portion (145) is provided.

[0031] In addition, the sealing method according to the present invention is characterized by including: (S1) a step of adjusting a contact position of the first stopper part and the second stopper part to correspond to the thickness of the sealing part; (S2) a step of positioning the sealing part between the first sealing tool and the second sealing tool; and (S3) a step of sealing by pressurizing and heating the sealing part through the first sealing tool and the second sealing tool.

[0032]

[0033] As described above, according to the sealing device of the pouch-type battery case according to the present invention and the sealing method using the same, one of the pair of sealing units is provided with a stopper part having a function of adjusting the gap between the pair of sealing tools, so that it can be used even if the thickness of the sealing part of the battery case is changed.

[0034] In addition, according to the sealing device of the pouch-type battery case according to the present invention and the sealing method using the same, the gap between a pair of sealing tools can be adjusted simply by rotating the stopper part clockwise or counterclockwise, so that the device is easy to operate and this can contribute to improving product productivity.

[0035]

[0036] Figure 1 is a drawing showing a sealing device of a pouch-type battery case according to the prior art sealing a secondary battery.

[0037] Figure 2 is a perspective view of a sealing device for a pouch-type battery case according to the present invention.

[0038] Figure 3 is a front view of a sealing device for a pouch-type battery case according to the present invention.

[0039] FIG. 4 is a drawing showing a pouch-type battery case mounted on a sealing device of a pouch-type battery case according to the present invention.

[0040] FIG. 5 is a drawing showing a sealing device of a pouch-type battery case according to the present invention pressurizing the pouch-type battery case.

[0041] Figure 6 is an enlarged perspective view of the first stopper portion constituting the sealing device of the pouch-type battery case according to the present invention.

[0042] Figure 7 is an enlarged perspective view of a second stopper portion constituting a sealing device of a pouch-type battery case according to the present invention.

[0043] Figure 8 is an exploded perspective view illustrating the coupling structure of the first stopper portion constituting the sealing device of the pouch-type battery case according to the present invention.

[0044] Fig. 9 is a cross-sectional view for explaining the coupling structure of the first stopper part constituting the sealing device of the pouch-type battery case according to the present invention.

[0045] FIG. 10 is a drawing for explaining the height adjustment of the first stopper part and the second stopper part that constitute the sealing device of the pouch-type battery case according to the present invention.

[0046]

[0047] Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail, so that those skilled in the art can easily implement the present invention. However, when describing the operating principles of preferred embodiments of the present invention in detail, if a detailed description of a related known function or configuration is judged to unnecessarily obscure the gist of the present invention, such detailed description will be omitted.

[0048] Additionally, the same drawing reference numerals are used for parts with similar functions and actions throughout the drawings. Throughout the specification, when a part is said to be connected to another part, this includes not only direct connections but also indirect connections with other elements intervening. Furthermore, inclusion of a component does not exclude other components unless specifically stated otherwise, but rather implies the inclusion of additional components.

[0049]

[0050] Hereinafter, a sealing device for a pouch-type battery case according to the present invention and a sealing method using the same will be described.

[0051] First, referring to FIG. 1, a pouch-type secondary battery (10) is configured to include an electrode assembly (11) in which a pair of electrode leads (not shown) are positioned facing each other or parallel in the same direction, and a battery case (12) that accommodates the electrode assembly (11).

[0052] Here, the electrode assembly (11) may be formed of a jelly-roll type electrode assembly having a structure in which a separator is interposed between long sheet-shaped cathodes and anodes and then rolled up, a stack type electrode assembly having unit cells having a structure in which rectangular cathodes and anodes are stacked with a separator interposed between them, a stack-folding type electrode assembly in which the unit cells are rolled up by a long separating film, or a lamination-stack type electrode assembly in which the unit cells are stacked with a separator interposed between them and attached to each other, but is not limited thereto.

[0053] The battery case (12) can accommodate the electrode assembly (11) using a laminate sheet composed of an outer covering layer, a metal layer, and an inner covering layer.

[0054] Since the inner covering layer is in direct contact with the electrode assembly (11), it must have insulation and electrolytic resistance, and in order to seal it from the outside, the sealing portion where the inner layers are thermally bonded must have excellent thermal bonding strength.

[0055] The metal layer in contact with the inner covering layer serves as a barrier layer that prevents moisture or various gases from penetrating into the battery from the outside, and a preferred material for this metal layer is an aluminum film that is lightweight and has excellent formability.

[0056] And the other side of the metal layer is provided with an outer covering layer, and this outer covering layer can use a heat-resistant polymer with excellent tensile strength, moisture permeability, and air permeability to protect the electrode assembly while ensuring heat resistance and chemical resistance, and examples thereof include, but are not limited to, nylon or polyethylene terephthalate.

[0057]

[0058] Fig. 2 is a perspective view of a sealing device for a pouch-type battery case according to the present invention, and Fig. 3 is a front view of the sealing device for a pouch-type battery case according to the present invention. In addition, Fig. 4 is a drawing showing a pouch-type battery case mounted on a sealing device for a pouch-type battery case according to the present invention, and Fig. 5 is a drawing showing a sealing device for a pouch-type battery case according to the present invention pressurizing a pouch-type battery case.

[0059] Referring to FIGS. 2 to 5, a device for sealing a sealing portion (S) of a battery case (12) having the above-described configuration includes a first sealing unit (100) and a second sealing unit (200).

[0060] First, the first sealing unit (100) can be configured to include a first heating block (110), a first support block (120), a first sealing tool (130), and a first stopper portion (140).

[0061] The first heating block (110) may be heated to a certain temperature and may be provided to transfer heat to the first sealing tool (130) via the first support block (120). The first heating block (110) may be provided with a conductor having high thermal conductivity (e.g., metal).

[0062] Additionally, a first heater (111) may be provided inside the first heating block (110). For example, the first heater (111) may be provided in a rod shape in the central portion inside the first heating block (110).

[0063] The first heater (111) may be provided to have a temperature that takes into account the temperature at which the sealing portion (S) of the battery case (12) is sealed, and the first heater (111) may have a heating wire that is heated by electricity supplied from an external electricity supply source (not shown).

[0064] The first support block (120) may be provided to be in close contact with the first heating block (110). The first support block (120) may be provided to be interposed between the first heating block (110) and the first sealing tool (130) to support the first sealing tool (130).

[0065] The first sealing tool (130) can be positioned in close contact with the first support block (120) to pressurize the lower surface (6 o'clock direction in FIGS. 4 and 5) of the sealing portion (S). This first sealing tool (130) can receive heat from the first heating block (110) described above to heat and pressurize the lower surface of the sealing portion (S).

[0066] Here, it is preferable that the first sealing tool (130) be provided with a length equal to or slightly longer than the length of the sealing portion (S) so that it can be in close contact with all sealing portions (S).

[0067] The first stopper portion (140) is located on both sides of the first support block (120) and is configured to adjust the distance between the first sealing unit (100) and the second sealing unit (200) when sealing the sealing portion (S) of the battery case (12), and a detailed description will be provided later.

[0068] Continuing, the second sealing unit (200) may be configured to include a second heating block (210), a second support block (220), a second sealing tool (230), and a second stopper portion (240).

[0069] The second heating block (210) may be heated to a certain temperature and may be provided to transfer heat to the second sealing tool (230) via the second support block (220). This second heating block (210) may be provided with a conductor having high thermal conductivity (e.g., metal).

[0070] Additionally, a second heater (211) may be provided inside the second heating block (210). For example, the second heater (211) may be provided in a rod shape in the central portion inside the second heating block (210).

[0071] The second heater (211) may be provided to have a temperature that takes into account the temperature at which the sealing portion (S) of the battery case (12) is sealed, and this second heater (211) may have a heating wire that is heated by electricity supplied from an external electricity supply source (not shown).

[0072] The second support block (220) may be provided to be in close contact with the second heating block (210). The second support block (220) may be provided to be interposed between the second heating block (210) and the second sealing tool (230) to support the second sealing tool (230).

[0073] The second sealing tool (230) can be positioned in close contact with the second support block (220) to pressurize the upper surface (12 o'clock direction in FIGS. 4 and 5) of the sealing portion (S). This second sealing tool (230) can receive heat from the second heating block (210) described above to heat and pressurize the upper surface of the sealing portion (S).

[0074] Here, it is preferable that the second sealing tool (230) be provided with a length equal to or slightly longer than the length of the sealing portion (S) so that it can be in close contact with all sealing portions (S).

[0075] The second stopper part (240) is located on both sides of the second support block (220) and is configured to adjust the distance between the first sealing unit (100) and the second sealing unit (200) when sealing the sealing part (S) of the battery case (12), and a detailed description will be provided later.

[0076] Meanwhile, in the sealing device of the present invention, the first heating block (110), the first support block (120), the first sealing tool (130), the second heating block (210), the second support block (220), and the second sealing tool (230) are obvious to those skilled in the art, so a more detailed description thereof will be omitted.

[0077] FIG. 6 is an enlarged perspective view of a first stopper part constituting a sealing device of a pouch-type battery case according to the present invention, and FIG. 7 is an enlarged perspective view of a second stopper part constituting a sealing device of a pouch-type battery case according to the present invention.

[0078] Also, FIG. 8 is an exploded perspective view for explaining the coupling structure of the first stopper part constituting the sealing device of the pouch-type battery case according to the present invention, FIG. 9 is a cross-sectional view for explaining the coupling structure of the first stopper part constituting the sealing device of the pouch-type battery case according to the present invention, and FIG. 10 is a drawing for explaining the state of adjusting the height of the first stopper part and the second stopper part constituting the sealing device of the pouch-type battery case according to the present invention.

[0079] The first stopper part and the second stopper part will be described with reference to FIGS. 2 to 10.

[0080] First, the first stopper portions (140) positioned on both sides of the first support block (120) are rotatably coupled. In other words, the first stopper portions (140) can rotate clockwise or counterclockwise with respect to one surface of the first support block (120).

[0081] This first stopper part (140) has an outer shape that is roughly cylindrical, and one end may be configured to include a contact surface (141) that is in close contact with the second stopper part (240), an insertion hole (142) in the center of the contact surface (141), a fastening member (143), and a packing member (144).

[0082] In detail, when sealing the sealing portion (S) of the battery case (12), the contact surface (141) on the outside of the insertion hole (142) is continuously inclined to have different heights along the circumference of the first stopper portion (140) so that the gap between the first sealing tool (130) and the second sealing tool (230) can be adjusted.

[0083] When fastening the first stopper part (140) to the first support block (120), the fastening member (143) inserted into the insertion hole (142) of the first stopper part (140) passes through the first stopper part (140) and is then fixed to the first sealing tool (130).

[0084] At this time, it is preferable that the fastening member (143) first penetrates the packing member (144) stored in the insertion hole (142), and then penetrates the first stopper part (140) and the first sealing tool (130) in that order.

[0085] In addition, it is more preferable that the packing member (144) be made of an elastic material including rubber or silicone, and the fastening member (143) may be a bolt having a head and a body.

[0086] The first stopper part (140) that is in close contact with the second stopper part (240) can rotate with respect to the first support block (120), but must not rotate easily in the rotated position.

[0087] To this end, in the present invention, since the fastening member (143) passes through the packing member (144), the first stopper part (140), and the first sealing tool (130) in that order, there is no need to separately manipulate the fastening member (143) even when rotating the first stopper part (140).

[0088] In other words, even if the fastening member (143) penetrates the packing member (144) and the first stopper portion (140) and is fixed to the first sealing tool (130), since the packing member (144) is made of an elastic material, the first stopper portion (140) can be rotated while being slightly pulled upward (in the 12 o'clock direction in Fig. 10). Of course, when the external force pulling it is released, the packing member (144) returns to its original volume, so the first stopper portion (140) is fixed in the rotated position.

[0089] The second stopper portion (240) located on both sides of the second support block (220) may have a blade shape with an inclined surface (241) provided on one end to make linear contact with the contact surface (141) of the first stopper portion (140) (see Fig. 7(a)).

[0090] As another example, the second stopper portion (240) located on both sides of the second support block (220) may have one end that is hemispherical in shape so as to make point contact with the contact surface (141) of the first stopper portion (140) (see Fig. 7(b)).

[0091] In particular, when the contact surface (141) of the first stopper portion (140) is continuously inclined and one end of the second stopper portion (240) has a blade shape as shown in Fig. 7(a), it is possible to more precisely adjust the gap between the first sealing tool (130) and the second sealing tool (230).

[0092] Meanwhile, the indicator portion (145) provided radially on the contact surface (141) can perform a function of indicating the gap between the first sealing tool (130) and the second sealing tool (230) when the blade-shaped second stopper portion (240) is positioned.

[0093] For example, if 30 is marked at a specific position of a dotted or solid line-shaped indicator (145), when the blade of the second stopper (240) is positioned at the indicator (145), it indicates that the gap between the first sealing tool (130) and the second sealing tool (230) is 30 mm.

[0094] Of course, this is just an example, and the spacing, number, and values ​​of the display unit (145) can be changed at any time.

[0095]

[0096] Next, with reference to FIGS. 2 to 10, a method for sealing a pouch-type battery case using the sealing device for the pouch-type battery case described above will be described.

[0097] The sealing method according to the present invention includes (S1) a step of adjusting the contact position of the first stopper part (140) and the second stopper part (240) to correspond to the thickness of the sealing part (S), (S2) a step of positioning the sealing part (S) between the first sealing tool (130) and the second sealing tool (230), and (S3) a step of sealing by pressurizing and heating the sealing part (S) through the first sealing tool (130) and the second sealing tool (230).

[0098] In step (S1), the first stopper part (140) can be rotated clockwise or counterclockwise to correspond to the thickness of the sealing part (S), thereby adjusting the overall protrusion height of the first stopper part (140) and the second stopper part (240).

[0099]

[0100] As described above, specific parts of the present invention have been described in detail. To those skilled in the art, such specific descriptions are merely preferred embodiments, and the scope of the present invention is not limited thereby. It is obvious to those skilled in the art that various changes and modifications are possible within the scope and technical idea of ​​the present invention, and it is natural that such changes and modifications fall within the scope of the appended patent claims.

[0101]

[0102] (Explanation of symbols)

[0103] 10: Pouch-type secondary battery

[0104] 11: Electrode assembly 12: Battery case

[0105] 100: 1st sealing unit

[0106] 110: First heating block 111: First heater

[0107] 120: First support block

[0108] 130: First sealing tool

[0109] 140: First stopper section

[0110] 141: Contact surface 142: Insertion hole

[0111] 143: Fastening member 144: Packing member

[0112] 145: Display

[0113] 200: Second sealing unit

[0114] 210: Second heating block 211: Second heater

[0115] 220: Second support block

[0116] 230: Second sealing tool

[0117] 240: Second stopper section 241: Inclined surface

[0118] S: Sealing part

Claims

1. A sealing device for sealing the sealing part of a battery case in which an electrode assembly is stored. A first sealing unit located on one side of the sealing portion of the above battery case; and A second sealing unit located on the other side of the sealing portion of the above battery case; The above first sealing unit, A sealing device comprising: a first heating block heated to a constant temperature; a first support block in close contact with the first heating block; a first sealing tool positioned in close contact with one surface of the first support block so as to press one surface of the sealing portion; and a pair of first stopper parts positioned on both sides of the first support block and rotatably coupled and having inclined contact surfaces formed to have different heights along the circumference.

2. In paragraph 1, A sealing device characterized in that the second sealing unit includes a second stopper part that is in close contact with the contact surface of the first stopper part, and the contact surface of the first stopper part and the second stopper part are in line contact or point contact.

3. In paragraph 2, A sealing device characterized in that the second sealing unit includes a second heating block heated to a constant temperature, a second support block in close contact with the second heating block, a second sealing tool positioned in close contact with one surface of the second support block so as to press the other surface of the sealing portion, and a pair of second stopper parts positioned on both sides of the second support block.

4. In paragraph 3, A sealing device characterized in that the second stopper portion has a blade shape with one end having a slope so as to make linear contact with the contact surface of the first stopper portion.

5. In paragraph 3, A sealing device characterized in that one end of the second stopper portion is hemispherical so as to make point contact with the contact surface of the first stopper portion.

6. In paragraph 2, A sealing device characterized in that an insertion hole is provided in the center of the contact surface of the first stopper part, and a fastening member for connecting the first support block and the first stopper part is accommodated in the insertion hole.

7. In paragraph 6, A sealing device characterized in that the above fastening member is a bolt.

8. In paragraph 7, A sealing device characterized in that a packing member is received in the above insertion hole, and the fastening member penetrates the packing member and is fastened to the first support block.

9. In paragraph 8, A sealing device characterized in that the above packing member is made of an elastic material.

10. In paragraph 9, A sealing device characterized in that the above packing member comprises a rubber or silicone material.

11. In paragraph 4, A sealing device characterized in that the above contact surface is provided with a radial marking portion.

12. In a sealing method using a sealing device according to any one of the first to eleventh clauses, (S1) A step of adjusting the contact position of the first stopper part and the second stopper part to correspond to the thickness of the sealing part; (S2) a step of positioning the sealing part between the first sealing tool and the second sealing tool; and (S3) A sealing method characterized by including a step of sealing by pressurizing and heating the sealing part through the first sealing tool and the second sealing tool.

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