Sealing apparatus and secondary battery sealing method

Abstract

A sealing apparatus according to one embodiment of the present invention is provided to seal an exterior material and a cover member of a secondary battery and may comprise an edge sealing unit provided to seal a plurality of edges formed between adjacent sealing surfaces among a plurality of sealing surfaces of the exterior material, the secondary battery comprising an electrode assembly, the exterior material having an inner space accommodating the electrode assembly and an exterior material opening allowing the inner space to communicate with the outside, and the cover member covering the exterior material opening of the exterior material so as for same to be sealed.

Description

Sealing device and secondary battery sealing method

[0001] [Cross-reference with related applications]

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0162751, filed November 21, 2023, the entire disclosure of which is incorporated herein by reference.

[0003] [Technical Field]

[0004] The present invention relates to a sealing device, and more particularly, to a sealing device provided to seal an outer material of a secondary battery.

[0005] Secondary batteries are highly applicable to a wide range of product groups and possess electrical properties that enable high energy density. These batteries are used not only in portable electronic devices but also in electric or hybrid vehicles powered by electrical power sources, as well as in power storage devices. Secondary batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency, not only because they can dramatically reduce fossil fuel use, but also because they produce no byproducts from energy use.

[0006] In general, a pouch-type secondary battery can be manufactured by stacking or winding an electrode assembly composed of a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode, embedding the electrode assembly in a battery case of a pouch sheet, and then injecting or impregnating the electrode assembly with an electrolyte.

[0007] Pouch-type secondary batteries can ensure airtightness by sealing the top and bottom surfaces of the pouch sheet that protrudes along the perimeter of the secondary battery. However, while this existing sealing method is suitable for thin secondary batteries, the production of high-energy secondary batteries has led to thicker secondary batteries. As a result, the areas requiring sealing are formed into three-dimensional structures. Therefore, sealing using existing sealing methods has the problem of making it difficult to ensure airtightness in the side and corner areas.

[0008] Therefore, there is a need to develop technology to solve the above problems.

[0009] The background technology described above is something that the inventor possessed or acquired in the process of deriving the disclosure of the present application, and cannot necessarily be said to be a publicly known technology disclosed to the general public prior to the present application.

[0010] The present invention has been devised to solve the above problems,

[0011] An object of one embodiment of the present invention is to provide a sealing device capable of efficiently sealing an edge formed between sealing surfaces.

[0012] An object of one embodiment of the present invention is to provide a sealing device capable of improving the sealing quality of a corner area of ​​an exterior material.

[0013] A sealing device according to one embodiment of the present invention may include an electrode assembly, an outer material having an internal space for accommodating the electrode assembly and an outer material opening for communicating the internal space with the outside, and a cover member for sealingly covering the outer material opening of the outer material, and may include a corner sealing portion provided to seal a plurality of corners formed between adjacent sealing surfaces among a plurality of sealing surfaces of the outer material.

[0014] The above corner sealing portion may include at least one corner sealing block having a curved shape corresponding to the shape of the corner.

[0015] The above corner sealing block may be arranged to be driven in a diagonal direction oblique to the sealing surface.

[0016] The above corner sealing portion may further include a support frame provided to support the secondary battery with respect to the driving of the corner sealing block.

[0017] The above support frame may be provided on the opposite side of the corner sealing block with the secondary battery therebetween.

[0018] The above corner sealing blocks may be provided in multiple numbers to correspond to the number of corners of the secondary battery.

[0019] A plurality of the above corner sealing blocks can be driven simultaneously in a direction toward the center of the secondary battery.

[0020] The above corner sealing block may have an L-shape.

[0021] At least a portion of the inner surface of the corner sealing block that comes into contact with the corner of the secondary battery may be formed into a curved surface.

[0022] The above corner sealing portion may further include an elastic pad that overlaps the inner surface of the corner sealing block so as to adhere closely to the corner.

[0023] The above sealing device may further include a sealing surface sealing portion that is provided to contact the sealing surface in a direction perpendicular to the sealing surface and seal the sealing surface.

[0024] The above sealing surface sealing portion may be provided so as not to overlap with the edge of the exterior material.

[0025] A sealing method of a secondary battery according to the present invention may include a sealing step of sealing a secondary battery including a plurality of sealing surfaces and a plurality of corners formed between the adjacent sealing surfaces, driving a sealing surface sealing unit provided to contact the sealing surfaces and seal the sealing surfaces to seal the sealing surfaces, and a corner sealing step performed after the sealing surface sealing step, driving a corner sealing unit having a plurality of corner sealing blocks having a curved shape corresponding to the shape of the corners to seal the corners.

[0026] The above corner sealing step may be a step of sequentially sealing the four corners of the secondary battery with a single corner sealing block.

[0027] The above corner sealing step may be a step performed simultaneously on four corners of the secondary battery using a plurality of corner sealing blocks.

[0028] A sealing device according to one embodiment of the present invention can efficiently seal an edge formed between sealing surfaces.

[0029] A sealing device according to one embodiment of the present invention can improve the sealing quality of a corner area of ​​an exterior material.

[0030] In addition, the configurations according to the embodiments of the present invention may include effects that can be easily predicted by those skilled in the art.

[0031] Figure 1 is an exploded perspective view of a secondary battery, which is a sealing target of a sealing device according to Example 1 of the present invention.

[0032] Figure 2 is a perspective view showing a schematic form of a combined secondary battery.

[0033] Figure 3 is a perspective view showing a form in which a pair of facing sealing surfaces are sealed by a sealing surface sealing portion.

[0034] Figure 4 is a perspective view showing another pair of sealing surfaces being sealed by a sealing surface sealing portion.

[0035] Fig. 5 is a perspective view showing the shape of the support frame of the corner sealing portion and the drive of the corner sealing block.

[0036] Fig. 6 is a perspective view showing a form in which an elastic pad is added to the inner surface of a corner sealing block.

[0037] Fig. 7 is a perspective view showing the driving form of a sealing device according to Example 2 of the present invention.

[0038] Hereinafter, with reference to the attached drawings, preferred embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the invention. The following description is one of several aspects of the embodiments, and in describing one embodiment, detailed descriptions of well-known functions or configurations will be omitted to clarify the gist of the present invention.

[0039] In this specification, when adding reference signs to components in each drawing, the same or similar reference signs are attached to identical or similar components throughout the specification. Components included in one embodiment and components that have common functions will be described using the same names in other embodiments. Terms or words used in this specification and the claims should not be interpreted as limited to their usual or dictionary meanings, and should be interpreted as meanings and concepts that are consistent with the technical spirit of the present invention based on the principle that the inventor can appropriately define the concept of the term to best explain his or her invention.

[0040] Furthermore, the present invention is not limited to the embodiments described above, and those skilled in the art will readily appreciate that various modifications and variations can be made based on this disclosure. Therefore, the spirit of the present invention should not be construed as limited to the embodiments described above, and all variations equivalent to or equivalent to the claims, as well as the scope of the claims, are deemed to fall within the scope of the present invention.

[0041] Example 1

[0042] Figures 1 and 2 illustrate a secondary battery, which is a sealing target of a sealing device according to Embodiment 1 of the present invention. Figure 1 is an exploded perspective view of a secondary battery, which is a sealing target of a sealing device according to Embodiment 1 of the present invention. Figure 2 is a perspective view schematically illustrating a combined secondary battery.

[0043] Referring to FIG. 1, the secondary battery to be sealed in the sealing device according to Example 1 of the present invention may include an electrode assembly (1), an outer material (20), and a cover member (10).

[0044] Electrode assembly (1)

[0045] The electrode assembly (1) can be prepared by stacking a positive electrode, a negative electrode, and a separator in a preset arrangement, and can have a rectangular shape having a longitudinal direction.

[0046] Electrode tabs may be formed at both ends of the electrode assembly (1). A plurality of positive electrode tabs may be placed at one end in the longitudinal direction of the electrode assembly (1), and a plurality of negative electrode tabs may be placed at the other end in a form in which they are joined to each other.

[0047] Exterior material (20)

[0048] The outer material (20) may be provided to accommodate the electrode assembly (1). The outer material (20) may have an internal space for accommodating the electrode assembly (1) and an outer material opening (2) that connects the internal space to the outside.

[0049] The exterior material (20) can be formed by rolling or folding a film-shaped exterior material sheet. The exterior material sheet forming the exterior material may be a sheet including a metal layer such as aluminum or stainless steel. The exterior material sheet may be a laminate sheet further including a resin layer laminated to the metal layer.

[0050] An outer covering (20) having outer covering openings (2) formed at both ends can be obtained by rolling or folding a film-shaped outer covering sheet so that both ends meet, and bonding the overlapping ends with an adhesive or by thermal fusion. The outer covering openings (2) can be provided at both ends in the longitudinal direction of the electrode assembly (1) accommodated in the outer covering (20).

[0051] Cover absence (10)

[0052] The cover member (10) may be a member that covers the outer material opening (2) of the outer material (20). In order to prevent leakage of the electrolyte that fills the internal space of the outer material (20) in which the electrode assembly (1) is accommodated, the cover member (10) may seal the outer material opening (2) of the outer material (20). The cover member (10) may be sealed with the outer material (20) by a sealing device according to the present invention while being coupled to both longitudinal ends of the outer material (20), thereby sealing the outer material opening (2) of the outer material (20). The cover members (10) may be formed as a pair corresponding to the outer material opening (2). The cover members (10) may be formed in a rectangular shape corresponding to the shape of the outer material opening (2).

[0053] Referring to Fig. 2, the outer material (20) may be covered by the cover member (10) while containing the electrode assembly (1) therein. The outer material (20) combined with the cover member (10) may be sealed with the cover member (10). The outer material (20) may include a sealing surface (21) and a corner (22).

[0054] Sealing surface (21) and corner (22)

[0055] The sealing surface (21) of the outer material (20) may be formed in multiple numbers. As illustrated, when the cover member (10) has a rectangular shape, four sealing surfaces may be formed on the outer material (20) along the circumferential direction of the cover member (10).

[0056] The corner (22) can be formed between two adjacent sealing surfaces (21). The corners (22) of the exterior material (20) can be formed in multiple numbers. For example, when the cover member (10) has a rectangular shape, four corners (22) can be formed on the exterior material (20) corresponding to the four corners of the rectangular cover member (10). As described above, the exterior material (20) includes a resin layer (e.g., polypropylene (PP), polyethylene terephthalate (PET), etc.) and is formed by being folded or rolled, so the corners (22) of the exterior material (20) can be formed in a round shape with a predetermined curvature.

[0057] Sealing surface sealing part (100)

[0058] Figures 3 and 4 illustrate a sealing surface sealing portion (100) of a sealing device according to Embodiment 1 of the present invention. Figure 3 is a perspective view illustrating a configuration in which a pair of sealing surfaces (21) facing each other are sealed by the sealing surface sealing portion (100). Figure 4 is a perspective view illustrating a configuration in which another pair of sealing surfaces (21) are sealed by the sealing surface sealing portion (100).

[0059] Referring to FIGS. 3 and 4, the sealing surface (21) of the exterior material (20) can be sealed by a sealing surface sealing portion (100). The sealing surface sealing portion (100) can include a pair of sealing blocks facing each other. The sealing blocks of the sealing surface sealing portion (100) can be provided to contact the sealing surface (21) of the exterior material (20) and apply heat and pressure to the sealing surface (21).

[0060] The sealing surface sealing portion (100) may include, for example, a first sealing block (101) arranged on one side of the exterior material (20), and a second sealing block (102) arranged on the other side of the exterior material (20) so as to face the first sealing block (101) with the exterior material (20) interposed therebetween. The first sealing block (101) and the second sealing block (102) may be arranged to face each other in parallel.

[0061] The first sealing block (101) and the second sealing block (102) can be driven in a direction toward each other while facing each other. The first sealing block (101) and the second sealing block (102) can be driven in a direction perpendicular to the sealing surface (21) to be sealed.

[0062] The sealing surface sealing unit (100) can simultaneously seal a pair of sealing surfaces facing each other among a plurality of sealing surfaces (21) formed along the outer circumference of the exterior material (20). Thereafter, the exterior material (20) may be rotated, for example, in one direction (see FIG. 3), so that another pair of sealing surfaces (21) that are not sealed can also be sealed by the sealing surface sealing unit (100) in the same manner. In this case, the area of ​​the sealing surface (21) sealed by the sealing surface sealing unit (100) may not overlap with the area of ​​the corner (22) sealed by the corner sealing unit to be described later. In other words, the sealing block of the sealing surface sealing unit (100) is provided so as not to overlap with the area of ​​the corner (22) of the exterior material (20), so that a double sealing phenomenon of the sealing surface sealing unit (100) and the corner sealing unit to be described later can be prevented.

[0063] Corner sealing part (200)

[0064] Figures 5 and 6 illustrate a corner sealing portion (200) of a sealing device according to Embodiment 1 of the present invention. Figure 5 is a perspective view showing the driving form of a support frame (202) and a corner sealing block (201) of the corner sealing portion (200). Figure 6 is a perspective view showing a form in which an elastic pad (2013) is added to the inner surface of the corner sealing block (201).

[0065] Referring to FIG. 5, the corner sealing portion (200) of the sealing device according to Embodiment 1 of the present invention may be provided to seal the corner (22) portion of the exterior material (20). The above-described sealing surface sealing portion (100) and the corner sealing portion (200) may be independently driven. Preferably, the sealing of the corner (22) of the exterior material (20) by the corner sealing portion (200) may be performed after the sealing of the sealing surface (21) of the exterior material (20) by the sealing surface sealing portion (100), but is not limited thereto.

[0066] Corner sealing block (201)

[0067] The corner sealing portion (200) may include a corner sealing block (201) that is provided to seal the corner by contacting the corner (22) of the exterior material (20). The corner sealing block (201) may seal the corner (22) of the cover member (10) and the exterior material (20) by pressing and heating the corner (22) of the exterior material (20).

[0068] The corner sealing block (201) may have a curved shape to correspond to the shape of the corner (22) of the exterior material (20). For example, the corner sealing block (201) may be provided to have an overall L-shape.

[0069] The corner (22) portion of the exterior material (20) can be pressed against the inner surface (2011) of the corner sealing block (201). The inner surface (2011) of the corner sealing block (201) can be provided in a shape corresponding to the shape of the outer surface of the exterior material (20). For example, the inner surface (2011) of the corner sealing block (201) can be formed to include a curved surface (2012) portion having a predetermined curvature corresponding to the corner (22) of the exterior material (20). By adopting the shape of the curved surface (2012), the inner surface of the corner sealing block (201) can be pressed against the corner (22) of the exterior material (20) more closely and the corner (22) portion can be pressed without any play.

[0070] The corner sealing block (201) can be driven in a diagonal direction oblique to the sealing surface (21). The driving direction of the corner sealing block (201) can be, for example, a direction toward the center of the cover member (10) having a rectangular shape.

[0071] Support frame (202)

[0072] The corner sealing portion (200) may further include a support frame (202). The support frame (202) may be provided to support the secondary battery with respect to the corner sealing block (201) that presses the secondary battery in a diagonal direction and is driven. The support frame (202) may be provided on the opposite side of the corner sealing block (201) with the secondary battery therebetween. The support frame (202) may be provided to contact and support at least one of the plurality of sealing surfaces of the outer material (20). The support frame (202) may be formed in a curved shape along the outer circumference of the outer material (20) of the secondary battery, for example, to support two adjacent sealing surfaces of the outer material (20). In this case, the support frame (202) may have an L-shape like the corner sealing block (201).

[0073] The corner sealing block (201) may be provided to seal one corner (22) of the secondary battery outer material (20) and then sequentially seal the remaining corners. In this case, the support frame (202) may be positioned on the opposite side of the corner sealing block (201) according to the operation of the corner sealing block (201) to support the secondary battery.

[0074] Elastic Pad (2013)

[0075] Referring to Fig. 6, an elastic pad (2013) may be provided on the inner surface (2011) of the corner sealing block (201) that comes into contact with the corner (22) of the exterior material (20). The elastic pad (2013) may be provided with a material having elasticity (e.g., rubber, silicone, urethane, etc.) and may overlap the inner surface (2011) of the corner sealing block (201) with a predetermined thickness.

[0076] By overlapping the inner surface (2011) of the corner sealing block (201) that presses the corner (22) of the exterior material (20), the corner (22) of the exterior material (20) can be pressed in close contact without any play, and the sealing quality of the corner (22) portion can be improved. In addition, even when the curvature of the curved surface (2013) area of ​​the inner surface (2011) of the corner sealing block (201) does not perfectly match the shape of the corner (22) of the exterior material (20), efficient sealing can be achieved by appropriately changing the shape of the elastic pad (2013).

[0077] Example 2

[0078] Fig. 7 is a perspective view showing the driving form of a sealing device according to Example 2 of the present invention.

[0079] Embodiment 2 of the present invention may differ from Embodiment 1 in that a plurality of corner sealing blocks (201) are provided corresponding to a plurality of corners (22) of the exterior material (20). Except for the difference, it should be noted that the contents of the sealing device according to Embodiment 1 of the present invention described above can be commonly applied to Embodiment 2 as well. Therefore, contents common to Embodiment 1 will be omitted as much as possible, and Embodiment 2 will be described focusing on the differences from Embodiment 1.

[0080] Referring to FIG. 7, the sealing device according to Embodiment 2 of the present invention may include a plurality of corner sealing blocks (201) corresponding to a plurality of corners (22) of the outer material (20). For example, when the cover member (10) is formed in a rectangular shape, four corner sealing blocks (201) may be provided corresponding to each of the four corners (22).

[0081] In this case, four corner sealing blocks (201) can be driven simultaneously to simultaneously seal multiple corners (22) of the outer material (20). Each corner sealing block (201) can be driven in a diagonal direction toward the center of the secondary battery. In this case, since the driving directions of one corner sealing block (201) and the corner sealing block (201) positioned opposite to it are opposite to each other, a separate support frame for supporting the secondary battery with respect to the corner sealing block (201) may not be required, and further, the time required for the sealing process may be reduced, thereby increasing process efficiency.

[0082] Sealing method

[0083] A sealing method of a secondary battery according to the present invention can be provided to seal a secondary battery including a plurality of sealing surfaces and a plurality of corners formed between adjacent sealing surfaces.

[0084] The sealing method of a secondary battery according to the present invention can be achieved through the components of the inventions described above. The sealing method of a secondary battery according to the present invention can include a sealing surface sealing step and an edge sealing step.

[0085] The sealing surface sealing step may be a step of sealing the sealing surface of the exterior material by driving the sealing surface sealing unit, and the edge sealing step may be a step of sealing the edge of the exterior material formed between the sealing surfaces by driving the edge sealing unit. The sealing process of the sealing surface and the edge of the exterior material is as described above.

[0086] At this time, the corner sealing step may be performed by sequentially sealing the four corners of the secondary battery with a single corner sealing block, or by simultaneously sealing the four corners of the secondary battery with multiple corner sealing blocks.

[0087] The sealing surface sealing step may be performed before the edge sealing step, but is not limited thereto, and the sealing surface sealing step may be performed after the edge sealing step.

[0088] The corners and sealing surfaces of the exterior material to be sealed in the corner sealing step and the sealing surface sealing step may be areas that do not overlap each other.

[0089] In the above description, although the present invention has been described by limited embodiments and drawings, the above description is merely an example of the technical idea of ​​the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations without departing from the essential characteristics of the present invention.

[0090] Accordingly, the embodiments disclosed in the present invention are intended to illustrate, rather than limit, the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical concepts within the scope equivalent thereto should be construed as being included within the scope of the present invention.

[0091] [Explanation of symbols]

[0092] 1: Electrode assembly

[0093] 2: Exterior opening

[0094] 10: Cover absence

[0095] 20: Exterior material

[0096] 21: Sealing surface

[0097] 22: Corner

[0098] 100: Sealing surface sealing part

[0099] 101: First sealing block

[0100] 102: Second sealing block

[0101] 200: Corner sealing part

[0102] 201: Corner sealing block

[0103] 2011: Inner side

[0104] 2012: Curved Surface

[0105] 2013: Elastic Pad

[0106] 202: Support frame

Claims

1. Electrode assembly; An outer material having an internal space for accommodating the electrode assembly and an outer material opening for communicating the internal space with the outside; and In a sealing device provided to seal the outer material of a secondary battery and the cover member, the outer material including a cover member that sealably covers the outer material opening of the outer material, A sealing device comprising: a corner sealing portion configured to seal a corner formed between adjacent sealing surfaces among a plurality of sealing surfaces positioned on different planes of the outer material; 2. In paragraph 1, The above corner sealing part is, A sealing device comprising at least one corner sealing block having a curved shape corresponding to the shape of the corner.

3. In paragraph 2, A sealing device in which the above corner sealing block is arranged to be driven in a diagonal direction oblique to the above sealing surface.

4. In paragraph 2, A sealing device, wherein the corner sealing portion further includes a support frame that is provided to support the secondary battery with respect to driving of the corner sealing block.

5. In paragraph 4, The above support frame is a sealing device provided on the opposite side of the corner sealing block with the secondary battery therebetween.

6. In paragraph 2, A sealing device in which the above corner sealing blocks are provided in multiple numbers corresponding to the number of corners of the secondary battery.

7. In paragraph 6, A sealing device in which a plurality of the above corner sealing blocks are driven simultaneously in a direction toward the center of the secondary battery.

8. In paragraph 2, The above corner sealing block is a sealing device having an L-shape.

9. In paragraph 8, A sealing device in which at least a portion of the inner surface of the corner sealing block that comes into contact with the corner of the secondary battery is formed into a curved surface.

10. In paragraph 8, The above corner sealing part is, A sealing device further comprising an elastic pad overlapping an inner surface of the corner sealing block so as to adhere closely to the corner.

11. In paragraph 1, A sealing device further comprising a sealing surface sealing portion provided to contact the sealing surface in a direction perpendicular to the sealing surface and seal the sealing surface.

12. In paragraph 11, A sealing device in which the sealing surface of the sealing portion is provided so as not to overlap with the edge of the outer material.

13. A sealing method for a secondary battery, which seals a secondary battery including a plurality of sealing surfaces and a plurality of edges formed between the adjacent sealing surfaces, A sealing surface sealing step for sealing the sealing surface by driving a sealing surface sealing part that is provided to contact the sealing surface and seal the sealing surface; and A secondary battery sealing method, comprising: a corner sealing step performed after the above-mentioned sealing surface sealing step, wherein a corner sealing unit having a plurality of corner sealing blocks having a curved shape corresponding to the shape of the corner is driven to seal the corner; 14. In paragraph 13, The above corner sealing step is a secondary battery sealing method that sequentially seals four corners of the secondary battery with a single corner sealing block.

15. In paragraph 13, A secondary battery sealing method, wherein the above corner sealing step is performed simultaneously on four corners of the secondary battery using a plurality of the above corner sealing blocks.

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