Sealing tip of apparatus that seals pouch-type secondary battery cell

Abstract

Disclosed is a sealing tip of an apparatus that seals a pouch-type secondary battery cell. The sealing tip may comprise: a connection block connected to the apparatus; a sealing block coupled to the connection block and having a contact surface in contact with a pouch exterior material of a secondary battery cell; an insulation plate interposed between the connection block and the sealing block; and a heater unit mounted inside the sealing block to be surrounded by an inner surface of the sealing block and one surface of the insulation plate.

Description

Sealing tip of a device for sealing pouch-type secondary battery cells

[0001] The present invention relates to a sealing tip of a device for sealing a pouch-type secondary battery cell, and more specifically, to a sealing tip configured to transmit heat of a film heater to the contact surface of a sealing block as much as possible, thereby enabling a sealing process of a pouch-type secondary battery cell without heat loss.

[0002] Lithium secondary batteries, with their high energy density, long lifespan, and low self-discharge rate, are widely used as core components in portable electronic devices, energy storage systems (ESS), and electric vehicles. Lithium secondary batteries are broadly classified into three types: prismatic, polymer, and cylindrical.

[0003] Here, polymer batteries are also called pouch-type secondary batteries because the electrode assembly is wrapped in an aluminum film (commonly called a pouch), and their use continues to increase as they can be made thinner and lighter.

[0004] During the manufacturing process of these pouch-type secondary batteries, there is a sealing process using heaters, etc., and the three representative processes are as follows.

[0005] 1) Process of inserting an electrode assembly (bicell) into a secondary battery pouch and sealing the side portion.

[0006] 2) A process for sealing the pouch along with a degassing process to remove gas from the pouch after filling the electrolyte inside the pouch.

[0007] 3) Sealing process to fix the terrace part, which is the outer part of the sealed pouch, after folding it.

[0008] The sealing process described above is performed in a sealing device, and the sealing tip provided in this sealing device is mainly a cartridge heater in the form of a rod, and heat is applied. Although the cartridge heater has the advantage of being easy to maintain, a temperature deviation may occur in each section depending on the internal winding ratio, heat may be radiated in all directions, resulting in heat loss, and since the distance from the contact surface of the sealing tip is far, the heat of the heater may not be sufficiently applied to the pouch-type secondary battery that touches the contact surface of the sealing tip.

[0009] The matters described in the background art above are intended to help understand the background of the invention and may include matters that are not publicly disclosed prior art.

[0010] The present invention has been devised to solve the above-described problem, and provides a sealing tip of a device for sealing a pouch-type secondary battery cell, which increases thermal conductivity by interposing a film heater between a cover block and a frame block made of aluminum and installing it inside a sealing block, and allows the heat of the film heater to be transferred to the contact surface of the sealing block as much as possible.

[0011] According to an embodiment of the present invention for solving the above-described problem, a sealing tip of a device for sealing a pouch-type secondary battery cell may include a connecting block connected to the device, a sealing block coupled to the connecting block and having a contact surface formed to come into contact with the secondary battery cell, an insulating plate interposed between the connecting block and the sealing block, and a heater part mounted inside the sealing block and surrounded by an inner surface of the sealing block and one surface of the insulating plate.

[0012] The heater unit may include a frame block mounted inside the sealing block and having a receiving groove formed therein, a film heater mounted in the receiving groove of the frame block, and a cover block mounted in the receiving groove of the frame block with the film heater interposed therebetween to cover the film heater.

[0013] The film heater can be arranged vertically inside the receiving groove.

[0014] The contact surface of the sealing block and one side of the film heater can be perpendicular to each other.

[0015] The film heater may have a cover block attached to one side and a frame block attached to the other side.

[0016] The frame block and cover block can be formed from aluminum material.

[0017] The insulation plate may include a first insulation plate interposed between the upper side of the connecting block and the upper surface of the sealing block to block heat transfer, and a second insulation plate interposed between the lower side of the connecting block and the rear surface of the sealing block to block heat transfer.

[0018] The heater part is mounted in the groove of the sealing block and is surrounded on three sides by the first inner surface, the second inner surface, and the third inner surface of the sealing block, and the rear side of the heater part can be surrounded by the front side of the second insulation plate.

[0019] The insulation board may be in the shape of an 'L' with a second insulation board arranged vertically on one end of a first insulation board arranged horizontally.

[0020] The sealing block can have a contact surface that comes into contact with the secondary battery cell when pressed in a vertical direction.

[0021] According to the sealing tip of the present invention, the heater part is mounted inside the sealing block and is surrounded on four sides by the first to third inner surfaces of the sealing block and the front surface of the second insulating plate, so that the contact area with the heater part is widened, and thus the heat of the heater part can be transferred to the contact surface of the sealing block to the greatest extent possible.

[0022] In addition, according to the sealing tip of the present invention, since the path through which heat from the heater unit is transferred to the connection block is blocked by the insulating plate and is concentrated on the sealing block, sufficient heat is applied to the contact surface of the sealing block without heat loss, so that the process of sealing a pouch-type secondary battery cell can be effectively performed.

[0023] In addition, according to the sealing tip of the present invention, since the cover block and the frame block covering one side and the other side of the film heater are formed of an aluminum material, the heat transfer rate to the contact surface of the sealing block increases, and the thermal parallelism characteristics can be improved.

[0024] In addition, according to the sealing tip of the present invention, since the film heater is mounted between the cover block and the frame block, the distance between one side of the film heater and the contact surface of the sealing block can be shortened, thereby increasing the heat transfer speed.

[0025] In addition, according to the sealing tip of the present invention, since the contact surface of the sealing block and one side of the film heater are perpendicular to each other, even if a force is applied in a vertical direction to press the contact surface of the sealing block against the pouch, the film heater is not pressed by the pressure and can be protected.

[0026] Figure 1 is a perspective view illustrating an example of a pouch-type secondary battery cell.

[0027] Figure 2 is a schematic diagram showing the sealing process of the pouch-type secondary battery of Figure 1.

[0028] FIG. 3 is a perspective view of a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention.

[0029] Figure 4 is an exploded perspective view of the front side of a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention.

[0030] FIG. 5 is an exploded perspective view of the back side of a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention.

[0031] Figure 6 is a cross-sectional view taken along line A-A' of Figure 3.

[0032] FIG. 7 is a front exploded perspective view showing a heater section at a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention.

[0033] FIG. 8 is a rear exploded perspective view showing a heater section at a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention.

[0034] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0035] These examples are provided to more fully illustrate the present invention to those skilled in the art. The following examples may be modified in various ways, and the scope of the present invention is not limited to the examples described below. Rather, these examples are provided to further faithfully and completely convey the spirit of the present invention.

[0036] The terms used herein are used to describe specific embodiments and are not intended to limit the present invention. Furthermore, the singular forms used herein may include the plural forms, unless the context clearly dictates otherwise.

[0037] In the description of the embodiments, when each layer (film), region, pattern or structure is described as being formed "on" or "under" the substrate, each layer (film), region, pad or pattern, "on" and "under" include both being formed "directly" or "indirectly" through another layer. In addition, the reference for above or below each layer is, in principle, based on the drawing.

[0038] The drawings are intended solely to facilitate understanding of the invention and should not be construed as limiting the scope of the invention. Furthermore, relative thicknesses, lengths, and sizes in the drawings may be exaggerated for convenience and clarity of explanation.

[0039] Fig. 1 is a perspective view illustrating an example of a pouch-type secondary battery cell, and Fig. 2 is a schematic diagram illustrating a sealing process of the pouch-type secondary battery of Fig. 1.

[0040] Referring to Fig. 1, a secondary battery cell (10) may be configured to include an electrode assembly (11) and a pouch outer case (12). Although not illustrated in detail, the electrode assembly (11) may be a stacked (laminated) electrode assembly in which a plurality of positive and negative electrode plates cut into predetermined size units are laminated with a separator interposed therebetween. The positive electrode lead (11a) and the negative electrode lead (11b) of the electrode assembly (11) may protrude from both sides of the pouch outer case (12), and may protrude from the same side according to an embodiment.

[0041] The pouch outer case (12) is configured to accommodate the electrode assembly (11) and the electrolyte, and may have a circumferential portion sealed. Here, the circumferential portions on both sides of the pouch outer case (12) where the positive electrode lead (11a) and the negative electrode lead (11b) are not arranged may be referred to as terraces (12a).

[0042] The terrace (12a) of the secondary battery cell (10) can be created during the sealing process of the pouch of the secondary battery. Subsequently, by folding the terrace using folding equipment, the terrace (12a) of the pouch outer material (12) can be folded and reduced in size, thereby improving space efficiency when mounted in a secondary battery pack.

[0043] A device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention can be used to seal a pouch outer material (12) to seal a pouch-type secondary battery, or to seal or pressurize a folded terrace (12a) after the terrace (12a) of the pouch-type outer material (12) is folded.

[0044] As illustrated in FIG. 2, the sealing tip (1) of the device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention can be positioned at the upper and lower portions with the pouch outer case (12) of the secondary battery cell (10) interposed therebetween, and is provided to be able to move up and down to pressurize and heat the pouch outer case (12). Here, the heating can be performed by the heater unit (400) included in the sealing tip (1). The pouch outer case (12) of the secondary battery cell (10) can be cooled and annealed after being pressurized and heated by the sealing tip (1). Accordingly, the internal stress of the terrace (12a) is removed, so that a springback phenomenon does not occur, and the terrace (12a) can be completely folded at 180 degrees.

[0045] FIG. 3 is a perspective view of a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention, FIG. 4 is a front-side exploded perspective view of a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention, FIG. 5 is a rear-side exploded perspective view of a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention, and FIG. 6 is a cross-sectional view taken along line A-A' of FIG. 3.

[0046] Referring to FIGS. 3 to 6, a sealing tip (1) according to an embodiment of the present invention is formed to be long along the longitudinal direction (X direction) so as to be able to seal a pouch-type secondary battery cell (10), and may be configured to include a connecting block (100), a sealing block (200), an insulating plate, and a heater part (400).

[0047] The connecting block (100) is connected to a device that seals a pouch-type secondary battery cell (10). Although not shown, the connecting block (100) may be provided to be coupled to a drive block (not shown) of the device so as to be able to move up and down. Here, the detailed configuration of the device that moves the connecting block (100) up and down is not a core matter of the present invention, and thus a detailed description thereof is omitted.

[0048] The connecting block (100) may be in the shape of an 'ㄱ' in which a lower part (120) is vertically connected to one end of an upper part (110). An insulating plate (300), a heater part (400), and a sealing block (200) may be placed in the space (130) between the upper part (110) and the lower part (120) of the connecting block (100).

[0049] The sealing block (200) has a contact surface (220) formed therein that comes into contact with a pouch-type secondary battery cell (10), and can be coupled to the connection block (100). The sealing block (200) can have a coupling hole (201) formed at a position corresponding to the coupling hole (101) of the connection block (100) for coupling with the connection block (100). Although not shown, a coupling means such as a bolt can be coupled by continuously penetrating the coupling hole (201) of the sealing block (200), the communication hole (323) of the second insulating plate (320), and the coupling hole (101) of the connection block (100), through which the sealing block (200), the second insulating plate (320), and the connection block (100) can be coupled.

[0050] The sealing block (200) may have a front surface (250) blocked and a groove (210) formed along the longitudinal direction (X direction) on the rear surface (240). A heater unit (400) may be placed inside the groove (210) of the sealing block (200). At this time, the first inner surface (211), the second inner surface (212), and the third inner surface (213) of the groove (210) may be in contact with the heater unit (400). In this way, the sealing block (200) is formed to surround three sides of the heater unit (400) through the first inner surface (211), the second inner surface (212), and the third inner surface (213), so that as the contact area with the heater unit (400) increases, the heat of the heater unit (400) can be transferred to the contact surface (220) of the sealing block (200) as much as possible.

[0051] An insulating plate (300) may be interposed between the connecting block (100) and the sealing block (200). The insulating plate (300) may be configured to include a first insulating plate (310) and a second insulating plate (320).

[0052] The first insulation plate (310) is interposed between the upper part (110) of the connection block (100) and the upper surface (230) of the sealing block (200) to block the heat of the heater part (400) arranged inside the sealing block (200) from being transferred to the connection block (100). The upper surface (311) of the first insulation plate (310) is in contact with the upper part (110) of the connection block (100), and the lower surface (312) of the first insulation plate (310) is in contact with the upper surface (230) of the sealing block (200). The second insulation plate (320) is interposed between the lower part (120) of the connection block (100) and the rear surface (240) of the sealing block (200) to block the heat of the heater part (400) from being transferred to the connection block (100). At this time, the front surface (321) of the second insulation plate (320) may be in contact with the rear surface (240) of the sealing block (200) and the heater section (400), and the rear surface (322) of the second insulation plate (320) may be in contact with the lower portion (120) of the connecting block (100). The insulation plate (300) may be in an 'ㄱ' shape in which the second insulation plate (320) is vertically arranged on one end of the first insulation plate (310) arranged horizontally.

[0053] The insulation plate (300) can play a role in concentrating the heat of the heater unit (400) toward the contact surface (220) of the sealing block (200) as much as possible. That is, the heat generated from the heater unit (400) must be concentrated toward the contact surface (220) of the sealing block (200) without heat loss so that the heat of the heater unit (400) can be sufficiently applied to the pouch-type secondary battery cell (10) that touches the contact surface (220) of the sealing block (200). If the insulation plate (300) is not provided, the heat of the heater unit (400) is transferred not only to the sealing block (200) but also to the connection block (100), so that the heat of the heater unit (400) cannot be concentrated toward the contact surface (220) of the sealing block (200). In addition, since the connecting block (100) is a part connected to a device for sealing the pouch outer material (12) of the pouch-type secondary battery cell (10), it is desirable that heat be applied as little as possible. Accordingly, the sealing tip (1) according to the embodiment of the present invention interposes an insulating plate (300) between the connecting block (100) and the sealing block (200), so that the heat of the heater part (400) inserted into the groove (210) of the sealing block (200) is blocked by the insulating plate (300) and is not transmitted to the connecting block (100), but is concentrated as much as possible on the sealing block (200).

[0054] In addition, the heater part (400) of the sealing tip (1) according to the embodiment of the present invention is mounted inside the sealing block (200) and is surrounded on three sides by the first to third inner surfaces (211, 212, 213) of the sealing block (200), and the rear surface of the heater part (400) is surrounded by the front surface (321) of the second insulating plate (320), and the path through which the heat from the heater part (400) is transferred to the connection block (100) is blocked by the insulating plate (300) and concentrated on the sealing block (200), so that heat is sufficiently applied to the contact surface (220) of the sealing block (200) without heat loss, so that the process of sealing the pouch-type secondary battery cell (10) can be effectively performed.

[0055] Hereinafter, the structure of the heater part (400) in the sealing tip (1) of the device for sealing a pouch-type secondary battery cell (10) according to an embodiment of the present invention will be described in detail.

[0056] FIG. 7 is a front exploded perspective view showing a heater part at a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention, and FIG. 8 is a back exploded perspective view showing a heater part at a sealing tip of a device for sealing a pouch-type secondary battery cell according to an embodiment of the present invention.

[0057] As shown in FIGS. 7 and 8, the heater unit (400) in the sealing tip (1) of the device for sealing a pouch-type secondary battery cell (10) according to an embodiment of the present invention may be configured to include a frame block (410), a film heater (420), and a cover block (430).

[0058] The frame block (410) is mounted inside the sealing block (200), and a receiving groove (413) may be formed along the longitudinal direction (X direction) on the front side (411), and the rear side (412) may be closed. A film heater (420) may be mounted inside the receiving groove (413) of the frame block (410). At this time, the film heater (420) may be arranged vertically inside the receiving groove (413), and a wiring connector (440) may be connected to one side.

[0059] Although not illustrated in detail, the film heater (420) may be equipped to improve temperature deviations by section by applying a heating wire of a certain pattern. That is, in the case of a cartridge heater, temperature deviations by section may occur depending on the internal winding ratio, but in the case of a film heater (420), a uniform temperature can be maintained by section by applying a heating wire of a certain pattern.

[0060] Since the film heater (420) is formed with a thin thickness, a space may remain even after the film heater (420) is mounted in the receiving groove (413), and the cover block (430) may be mounted in the remaining space of the receiving groove (413). That is, the cover block (430) may be mounted in the receiving groove (413) of the frame block (410) with the film heater (420) interposed therebetween to cover the film heater (420). The cover block (430) may be configured to include a first cover block (431) and a second cover block (432). For example, the cover block (430) may be mounted with a second cover block (432) that covers most of the area of ​​the film heater (420), and then a first cover block (431) that covers the connection portion of the wiring connector (440) and the film heater (420) may be mounted, but this is not limited thereto, and the first cover block (431) and the second cover block (432) may be formed integrally.

[0061] The film heater (420) has a cover block (430) attached to one side (421) and a frame block (410) attached to the other side (422), and may be formed of an aluminum material to increase heat transfer efficiency. Since aluminum is a material with high thermal conductivity, when the cover block (430) and the frame block (410) surrounding the film heater (420) are made of aluminum, the heat transfer speed to the contact surface (220) of the sealing block (200) increases, the thermal parallelism characteristics can be improved, and the temperature deviation problem by section can be improved due to the thermal diffusivity of aluminum, so that the pouch-type secondary battery cell (10) can be uniformly sealed as a whole, thereby improving the thickness quality.

[0062] In addition, since the film heater (420) is mounted between the cover block (430) and the frame block (410), the distance between one side (421) of the film heater (420) and the contact surface (220) of the sealing block (200) can be shortened. That is, in the case of a rod-shaped cartridge heater, the distance from the contact surface (220) of the sealing block (200) is far when mounted on the sealing block (200), but in the case of the film heater (420), since it is relatively small in size and thinner in thickness, it is possible to be mounted between the cover block (430) and the frame block (410), so that one side (421) of the film heater (420) can be brought closer to the contact surface (220) of the sealing block (200) by the thickness of the portion where the receiving groove (413) is formed in the frame block (410), thereby increasing the heat transfer speed.

[0063] Meanwhile, as described above, the sealing block (200) is connected to a device for sealing a pouch-type secondary battery cell (10) and can pressurize the folded terrace (12a) in the vertical direction during the sealing process. When the sealing block (200) presses the folded terrace (12a) in the vertical direction, the contact surface (220) can come into contact with the folded terrace (12a) of the secondary battery cell (10). At this time, since the contact surface (220) of the sealing block (200) and one side (421) of the film heater (420) are perpendicular to each other, even if a force is applied in the vertical direction so that the contact surface (220) of the sealing block (200) presses the folded terrace (12a), the film heater (420) is not pressed by the pressure. If one side (421) of the film heater (420) is parallel to the contact surface (220) of the sealing block (200), when force is applied in a vertical direction to press the folded terrace (12a) against the contact surface (220) of the sealing block (200), the area on which pressure is applied to the film heater (420) increases, which may cause damage. Therefore, one side (421) of the film heater (420) is arranged vertically with respect to the contact surface (220) of the horizontally formed sealing block (200), thereby protecting the film heater (420) from damage that may occur when the sealing block (200) is pressed in the vertical direction.

[0064] In the embodiment of the present invention, an example in which the sealing tip (1) is applied to sealing a pouch-type secondary battery cell (10) is described, but the present invention is not limited thereto, and the sealing tip according to the present embodiment can also be applied in the manufacture of other secondary batteries.

[0065] The above description is merely an illustrative illustration of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the technical idea of ​​the present invention, and the scope of the technical idea 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 ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

[0066] The present invention relates to a sealing tip of a device for sealing a pouch-type secondary battery cell.

Claims

1. As a sealing tip of a device for sealing a pouch-type secondary battery cell, A connection block connected to the above device; A sealing block coupled to the above connecting block and having a contact surface formed that comes into contact with the pouch outer material of the secondary battery cell; An insulating plate interposed between the above connecting block and the above sealing block; and A heater part mounted inside the sealing block and surrounded by the inner surface of the sealing block and one surface of the insulating plate; A sealing tip of a device for sealing a pouch-type secondary battery cell including a .

2. In paragraph 1, The above heater part, A frame block mounted inside the above sealing block and having a receiving groove formed therein; A film heater mounted in the receiving groove of the above frame block; and A cover block mounted in a receiving groove of the frame block with the film heater interposed therebetween and covering the film heater; A sealing tip of a device for sealing a pouch-type secondary battery cell including a .

3. In paragraph 2, The above film heater is a sealing tip of a device that seals pouch-shaped secondary battery cells arranged vertically inside the receiving groove.

4. In paragraph 2, A sealing tip of a device for sealing a pouch-type secondary battery cell, wherein the contact surface of the sealing block and one side of the film heater are perpendicular to each other.

5. In paragraph 2, The above film heater, A sealing tip of a device for sealing a pouch-type secondary battery cell, in which the cover block is adhered to one side and the frame block is adhered to the other side.

6. In paragraph 2, The above frame block and the cover block are sealing tips of a device for sealing a pouch-shaped secondary battery cell formed of aluminum material.

7. In paragraph 1, The above insulation board, A first insulating plate interposed between the upper part of the above connecting block and the upper surface of the above sealing block to block heat transfer; and A sealing tip of a device for sealing a pouch-shaped secondary battery cell, the device including a second insulating plate interposed between the lower part of the above-mentioned connecting block and the rear surface of the sealing block to block heat transfer.

8. In paragraph 7, The above heater part is mounted in the groove of the sealing block and is surrounded on three sides by the first inner surface, the second inner surface, and the third inner surface of the sealing block, The rear side of the above heater section is a sealing tip of a device that seals a pouch-shaped secondary battery cell wrapped by the front side of the second insulating plate.

9. In paragraph 7, The above insulation board, A sealing tip of a device for sealing a pouch-shaped secondary battery cell in an 'ㄱ' shape, with the second insulating plate arranged vertically on one end of the first insulating plate arranged horizontally.

10. In paragraph 1, The above sealing block is a sealing tip of a device for sealing a pouch-type secondary battery cell, wherein the contact surface comes into contact with the pouch outer material of the secondary battery cell when pressed in a vertical direction.

Images