Sealing device comprising bent portion, and pouch-type battery cell manufactured using sealing device

Abstract

The present invention relates to a sealing device and a pouch-type battery cell manufactured using the sealing device, the sealing device comprising: a first sealing jig for pressing a first surface of the pouch-type battery cell; and a second sealing jig for pressing a second surface of the pouch-type battery cell, wherein each of the first sealing jig and the second sealing jig includes a flat portion having a flat pressing surface, and a bent portion which is one end of the flat portion and which is bent to be inclined at a predetermined angle with respect to the flat portion.

Description

A sealing device including a folded portion and a pouch-type battery cell manufactured using said sealing device

[0001] This application claims the benefit of priority based on Korean Patent Application No. 2024-0198524 filed December 27, 2024 and Korean Patent Application No. 2025-0206657 filed December 22, 2025, and all contents disclosed in the documents of said Korean patent applications are incorporated herein as part of this specification.

[0002] The present invention relates to a sealing device including a folded portion and a pouch-type battery cell manufactured using the sealing device. Specifically, to solve the problem of the width of the battery cell increasing when a sealing portion is formed at both ends of the outer periphery where the folding line of a pouch-type battery case is located, the invention relates to a sealing device including a folded portion with a deformed pressure surface and a pouch-type battery cell manufactured using the sealing device.

[0003]

[0004] Lithium-ion batteries are classified into cylindrical, prismatic, and pouch types based on the shape of the case. Cylindrical and prismatic batteries are batteries with a structure in which an electrode assembly is mounted in a metal can, while pouch-type batteries are batteries with a structure in which an electrode assembly is mounted in a pouch-type battery case, typically made of an aluminum laminate sheet. Pouch-type batteries have the advantages of being able to be stacked with high integration density, having high energy density per unit weight, being inexpensive, and easy to deform.

[0005] Pouch-type battery cases can be classified into separable battery cases in which the upper case and lower case are separated from each other, and integrated battery cases in which the upper case and lower case are connected to each other. Regardless of whether the upper case and lower case are separated, they can also be classified into one cavity battery cell in which the electrode assembly housing is composed of one, and two cavity battery cells in which the electrode assembly housing is composed of a total of two, with the upper case and lower case respectively.

[0006] Pouch-type battery cells are typically sealed via thermal fusion. In the case of detachable pouch-type battery cases, uniform thermal fusion is achieved around the outer periphery of the electrode assembly housing, preventing issues such as seal slippage.

[0007] In integrated pouch-type battery cases, when sealing the sealing portion, the adhesive layer of the laminate sheet is subjected to pressure and is pushed outward around the outer edge of the fold. Because the part of the sealing portion that is partially stretched due to this pushing of the adhesive layer resembles a bat's ear, it is called a bat ear.

[0008] FIG. 1 is a perspective view and a partial enlarged view of a pouch-type battery cell, FIG. 2 is a plan view and a front view of a conventional sealing device, and FIG. 3 is a front view of a pouch-type battery cell with a conventional sealing device placed thereon.

[0009] Referring to FIGS. 1 to 3, the pouch-type battery cell (100) is a bidirectional battery cell configured such that a positive lead (111) and a negative lead (112) protrude in opposite directions, and an electrode assembly housing (120) is formed to accommodate an electrode assembly. The pouch-type battery case includes a first case (101) and a second case (102), and the first case (101) and the second case (102) are formed as an integrated battery case that is folded and heat-fused so that their outer edges overlap each other.

[0010] The above-mentioned integrated battery case is folded at a folding line (124) adjacent to the electrode assembly housing, so that the outer periphery of the first case (101) and the outer periphery of the second case (102) are heat-fused, and a first sealing part (121), a second sealing part (122), and a third sealing part (123) are formed along the outer periphery of the electrode assembly housing (120), and a folding line (124) is formed opposite the third sealing part (123).

[0011] The sealing device includes a first sealing jig (200) and a second sealing jig (300) located on the upper and lower surfaces of a pouch-type battery case, respectively. The first sealing jig (200) includes a first pressure part (220) and a first main body part (210) that applies pressure to the first pressure part (220), and the second sealing jig (300) includes a second pressure part and a second main body part that applies pressure to the second pressure part.

[0012] Referring to FIG. 2, (a) is a plan view of the first sealing jig (200), and (b) is a front view of the first sealing jig (200). The entire pressure surface (230) formed on the first pressure part (220) of the first sealing jig (200) is configured in a planar shape.

[0013] In the case of a pouch-type battery cell (100) using an integrated battery case illustrated in Fig. 1, during the heat fusion process, the corner where the first sealing part (121) and the second sealing part (122) meet the folding line (124) protrudes further than the folding line (124), forming a deformation part (130) called a bat-ear.

[0014] Since the dimensions of the battery case increase due to the deformation part (130), when the relevant part or surrounding part is bent, stress is concentrated and the battery case is damaged. In addition, there is a problem that the battery dimensional defects tend to occur in consecutive cells, resulting in a very high defect level, such as a defect rate of 60% to 80%.

[0015] Patent Document 1 discloses a configuration in which a protrusion is folded using a separate roller to remove a first side sealing portion formed at both ends of a pouch film and a protrusion formed at the end of a second side sealing portion.

[0016] Patent Document 2 describes a battery cell comprising a folding portion folded along one edge of an electrode assembly and a sealing portion formed along the remaining edge of the electrode assembly, wherein the portion where the sealing portion and the folding portion intersect includes a bending portion bent toward the sealing portion.

[0017] The protrusion of Patent Document 1 and the bending part of Patent Document 2 correspond to the deformation part (130) described above, and a method of folding the deformation part using a separate device is used to remove it. In addition, this method requires an additional process separate from the sealing part formation process.

[0018] (Prior Art Literature)

[0019] (Patent Document 1) Korean Published Patent Application No. 2023-0013599 (January 26, 2023)

[0020] (Patent Document 2) Korean Published Patent Application No. 2023-0034601 (March 10, 2023)

[0021]

[0022] The present invention aims to solve the above-mentioned problem by providing a sealing device including a folded portion and a pouch-type battery cell manufactured using said sealing device, in order to prevent defective battery cells from occurring due to deformation in the sealing portion adjacent to the folding line in a pouch-type battery cell.

[0023]

[0024] A sealing device according to the present invention for achieving such an objective comprises a first sealing jig for pressing a first surface of a pouch-type battery cell and a second sealing jig for pressing a second surface of the pouch-type battery cell, wherein the first sealing jig and the second sealing jig may include a flat portion having a flat surface for pressing, and a bent portion having one end of the flat portion that is bent to be inclined at a certain angle to the flat portion.

[0025] In a sealing device according to the present invention, the first sealing jig may include a first pressure portion in which a first flat portion and a first bend portion are continuously arranged, and a first main body portion for supporting the first pressure portion and fixing it to a pressure device, and the second sealing jig may include a second pressure portion in which a second flat portion and a second bend portion are continuously arranged, and a second main body portion for supporting the second pressure portion and fixing it to a pressure device.

[0026] In the sealing device according to the present invention, in the first sealing jig, the first pressure surface of the first planar portion is parallel to the first surface of the pouch-type battery cell, and the first bend portion is bent toward the first main body portion with respect to the first pressure surface, and in the second sealing jig, the second pressure surface of the second planar portion is parallel to the second surface of the pouch-type battery cell, and the second bend portion can be bent toward the second main body portion with respect to the second pressure surface.

[0027] In the sealing device according to the present invention, the bending angle of the first connecting part and the bending angle of the second connecting part may be configured to be the same.

[0028] In the sealing device according to the present invention, the bending angle of the first bending portion and the bending angle of the second bending portion may be formed to be greater than 0° and less than or equal to 90°.

[0029] In the sealing device according to the present invention, the bending angle of the first bending portion and the bending angle of the second bending portion may be formed to be 10° or more and 45° or less.

[0030] In the sealing device according to the present invention, the connecting portion connecting the flat portion and the bent portion may be formed as a curved surface.

[0031] In a sealing device according to the present invention, the first sealing jig includes a first inner surface which is an outer surface close to the pouch-type battery cell and a second outer surface which is opposite to the first inner surface, and the first bending part is configured such that the height of the first outer surface is lower than the height of the first inner surface, and the second sealing jig includes a second inner surface which is an outer surface close to the pouch-type battery cell and a second outer surface which is opposite to the second inner surface, and the second bending part may be configured such that the height of the second outer surface is higher than the height of the second inner surface.

[0032] In the sealing device according to the present invention, the folded portion may be located at a portion corresponding to both ends of the outer periphery opposite to the gas discharge direction in the pouch-type battery cell.

[0033] A pouch-type battery cell manufactured using a sealing device according to the present invention comprises an electrode assembly and a pouch-type battery case housing the electrode assembly, wherein the pouch-type battery case comprises a first case and a second case that are heat-fused to each other along the outer periphery, and a folded sealing portion may be formed at least one corner portion of the sealing portion where the first case and the second case are heat-fused.

[0034] In a pouch-type battery cell according to the present invention, the first case and the second case are formed as an integrated unit that is folded along a folding line and has an outer periphery heat-fused, and the folding sealing portion may be formed adjacent to the folding line.

[0035] In the pouch-type battery cell according to the present invention, the boundary between the folded sealing portion and the flat sealing portion, which is the remaining unfolded sealing portion, may be formed in the shape of an angled corner.

[0036] In the pouch-type battery cell according to the present invention, the boundary between the folded sealing portion and the flat sealing portion, which is the remaining unfolded sealing portion, may be formed in a curved shape.

[0037] In a pouch-type battery cell according to the present invention, the fold sealing portion includes an inner portion adjacent to an electrode assembly housing portion and an outer portion opposite to the inner portion, and the outer portion may be formed in a shape in which it is folded further toward the first case than the inner portion.

[0038] In the pouch-type battery cell according to the present invention, the boundary between the folded sealing portion and the flat sealing portion may be formed parallel to the folding line.

[0039] In the pouch-type battery cell according to the present invention, the boundary between the fold sealing portion and the flat sealing portion may be formed in a shape inclined with respect to the extension of the folding line.

[0040]

[0041] The present invention can also be provided in a form that combines various means for solving the above problem.

[0042]

[0043] The present invention can prevent defective battery cells from occurring by reducing the planar area of ​​the deformation portion where the sealing portion of a pouch-type battery cell is deformed.

[0044] In addition, since a pouch-type battery cell as described above can be manufactured by modifying the shape of the sealing device itself, the occurrence of defects in the pouch-type battery cell can be reduced solely through the sealing process without adding a separate process other than the sealing process.

[0045]

[0046] Figure 1 is a perspective view and a partial enlarged view of a pouch-type battery cell.

[0047] Figure 2 is a plan view and a front view of a conventional sealing device.

[0048] FIG. 3 is a front view of a pouch-type battery cell with a conventional sealing device placed thereon.

[0049] FIG. 4 is a plan view and a front view of a sealing device according to the present invention.

[0050] Figure 5 is a front view for comparing the sealing device of Figure 3 and the sealing device of Figure 4.

[0051] FIG. 6 is a front view of a pouch-type battery cell with the sealing device of the present invention placed thereon.

[0052] FIG. 7 is a perspective view of a sealing device according to the first embodiment placed in a pouch-type battery cell.

[0053] FIG. 8 is a perspective view of a portion of a pouch-type battery cell manufactured using the sealing device of FIG. 7.

[0054] FIG. 9 is a perspective view of a sealing device according to a second embodiment placed in a pouch-type battery cell.

[0055] FIG. 10 is a perspective view and a partial enlarged view of a pouch-type battery cell manufactured using the sealing device of FIG. 9.

[0056] FIG. 11 is a perspective view of a sealing device according to the third embodiment placed in a pouch-type battery cell.

[0057] FIG. 12 is a perspective view of a pouch-type battery cell manufactured using the sealing device of FIG. 11.

[0058]

[0059] Embodiments that enable a person skilled in the art to easily practice the present invention are described in detail below with reference to the attached drawings. In describing the operating principles of the embodiments of the present invention in detail, specific descriptions of related known functions or configurations are omitted if it is determined that such detailed descriptions may unnecessarily obscure the essence of the present invention.

[0060] The same reference numerals are used for parts having similar functions and operations throughout the drawings. Throughout the specification, when a part is described as being connected to another part, this includes not only cases where they are directly connected but also cases where they are indirectly connected with other elements in between. Furthermore, the inclusion of a certain component means that, unless specifically stated otherwise, it does not exclude other components but rather implies that additional components may be included.

[0061] Descriptions that specify components by limiting or adding them may be applied to all inventions unless specifically limited, and are not limited to descriptions of specific inventions.

[0062] Throughout the description of the invention and claims of this application, anything indicated in the singular includes cases where it is plural unless otherwise noted.

[0063] Throughout the description of the invention and the claims of the present invention, "or" includes "and" unless otherwise noted. Therefore, "comprising A or B" means all three of the above cases: including A, including B, or including both A and B.

[0064] The present invention is described in detail with reference to the drawings and embodiments.

[0065] FIG. 4 is a plan view and a front view of a sealing device according to the present invention, FIG. 5 is a front view for comparing the sealing device of FIG. 3 and the sealing device of FIG. 4, and FIG. 6 is a front view of the sealing device of the present invention placed in a pouch-type battery cell.

[0066] Referring to FIGS. 4 to 6, the sealing device according to the present invention includes a first sealing jig (200) for pressing a first surface of a pouch-type battery cell and a second sealing jig (300) for pressing a second surface of a pouch-type battery cell, and the first sealing jig (200) and the second sealing jig (300) each include a flat portion having a flat surface for pressing, and a bent portion having one end of the flat portion that is bent to be inclined at a certain angle to the flat portion.

[0067] The first surface above may be the upper surface of the pouch-type battery cell, and the second surface above may be the lower surface of the pouch-type battery cell.

[0068] FIG. 4 (a) is a plan view of the first sealing jig (200), FIG. 4 (b) is a front view of the first sealing jig (200), FIG. 4 (c) is a plan view of the second sealing jig (300), and FIG. 4 (d) is a front view of the second sealing jig (300).

[0069] The first sealing jig (200) includes a first pressure portion (220) in which a first flat portion (221) and a first bend portion (222) are arranged continuously, and a first main body portion (210) for supporting the first pressure portion (220) and fixing it to a pressure device.

[0070] The second sealing jig (300) includes a second pressure part (320) in which a second flat part (321) and a second bent part (322) are arranged continuously, and a second main body part (310) for supporting the second pressure part (320) and fixing it to a pressure device.

[0071] The flat portion includes a first flat portion (221) and a second flat portion (321), and the fold portion includes a first fold portion (222) and a second fold portion (322), and the flat portion and the fold portion are in close contact with and pressurized by a pouch-type battery case.

[0072] The above-mentioned planar portion includes a first area (A) that presses the venting direction sealing portion of the pouch-type battery case and a second area (B) that presses the outer periphery where the electrode lead is placed. In the second area (B), the portion where the electrode lead is placed among the first pressing surface (223) and the second pressing surface (323) may be configured to be more concave than the first pressing surface (223) and the second pressing surface (323) of the first area (A) in consideration of the thickness of the electrode lead and the lead film; however, in this specification, the concave shape of the portion where the electrode lead is placed in the second area (B) is considered to be included in the planar portion.

[0073] The first sealing jig (200) and the second sealing jig (300) are fixed to a pressure device for applying pressure, and can move to move closer to each other to pressurize a pouch-type battery case or move away from each other after sealing. The first main body part (210) and the second main body part (220) may include a fastening structure for using fastening members such as bolts.

[0074] In the first sealing jig (200), the first pressure surface (223) of the first flat portion (221) is parallel to the first surface, which is the intended sealing portion of the pouch-type battery cell, and the first bending portion (222) is bent toward the first main body portion (210) with respect to the first pressure surface (223); and in the second sealing jig (300), the second pressure surface (323) of the second flat portion (321) is parallel to the second surface, which is the intended sealing portion of the pouch-type battery cell, and the second bending portion (322) is bent so as to move away from the second main body portion (310) with respect to the second pressure surface (323).

[0075] The first sealing jig (200) and the second sealing jig (300) are in close contact with each other with the pouch-type battery case interposed between them, and heat-seal the outer periphery of the pouch-type battery case. Accordingly, the bending angle (θ) of the first connecting part (224) and the bending angle (θ) of the second connecting part (324) are configured to be the same size.

[0076] The bending angle (θ) refers to the angle at which the first pressure surface (223) of the first bending part (222) is bent relative to the first pressure surface (223) of the first planar part (221), and the angle at which the second pressure surface (323) of the second bending part (322) is bent relative to the second pressure surface (323) of the second planar part (321). That is, the closer the bending angle is to 0, the more parallel the first bending part (222) and the second bending part (322) are to the first planar part (221) and the second planar part (321), respectively, and the greater the bending angle, the greater the angle at which the first bending part (222) and the second bending part (322) are bent.

[0077] Specifically, the first connecting part (224) and the second connecting part (324) may be configured in an angular shape, and the bending angle (θ) of the first connecting part (224) and the bending angle of the second connecting part (324) may be formed to be greater than 0° and less than or equal to 90°, and more specifically, formed to be greater than or equal to 10° and less than or equal to 45°, and more specifically, formed to be greater than or equal to 10° and less than or equal to 30°.

[0078] Alternatively, in another specific example, the connecting portion where the flat portion and the folded portion are connected may be formed in an angular shape or in a curved shape. Considering the sealing force of the sealing portion of the pouch-type battery case and the prevention of crack formation, it is preferable for the connecting portion to be formed in a curved shape.

[0079] Referring to FIG. 5, the length (L2) of the sealing device of the present invention is formed to be shorter than the length (L1) of a conventional sealing device. For example, when the length of the part where the bend is formed in (a) is x, the length becomes x(1-cosθ) when the bend is formed as in (b). Specifically, when the bend angle (θ) is 20° and the bat length is 4.58mm, the effect of reducing by 0.28mm can be obtained.

[0080] FIG. 7 is a perspective view of a sealing device according to the first embodiment placed in a pouch-type battery cell.

[0081] Referring to FIG. 7, a pouch-type battery cell (100) is placed between the first sealing jig (200) and the second sealing jig (300).

[0082] FIG. 7 shows only the first pressure part (220) of the first sealing jig (200) and only the second pressure part (320) of the second sealing jig (300).

[0083] In the first sealing jig (200), the first pressure portion (220) includes a first inner surface (222a) which is the outer periphery close to the pouch-type battery cell (100) and a first outer surface (222b) which is the opposite side of the first inner surface (222a), and the first bend portion (222) has the same height (H1a) of the first inner surface and the same height (H1b) of the first outer surface.

[0084] In the second sealing jig (300), the second pressure portion (320) includes a second inner surface (322a) which is the outer periphery close to the pouch-type battery cell (100) and a second outer surface (322b) which is the opposite side of the second inner surface (322a), and the second bend portion (322) has the same height (H2a) of the second inner surface and the same height (H2b) of the second outer surface.

[0085] That is, in the first sealing jig (200) and the second sealing jig (300) illustrated in FIG. 7, when the first pressure surface (223) of the first planar portion (221) and the second pressure surface (323) of the second planar portion (321) are each in the xy plane, the first pressure surface (223) of the first bending portion (222) and the second pressure surface (323) of the second bending portion (322) can each be bent by rotating along the y-axis with respect to the xy plane.

[0086] In addition, the first connecting part (224) to which the first planar part (221) and the first bending part (222) are connected, and the second connecting part (324) to which the second planar part (321) and the second bending part (322) are connected are provided parallel to the y-direction parallel to the length of the folding line (124) or the pouch-type battery cell (100).

[0087] In the case of the sealing device illustrated in FIG. 7, the measurement location of the bending angle (θ) of the first connecting part (224) and the bending angle (θ) of the second connecting part (324) can be designated as a specific part of the first connecting part (224) or the second connecting part (324), and in detail, can be measured at the first connecting part (224) that meets the first inner surface (222a) or at the second connecting part (324) that meets the second inner surface (322a), or at the first connecting part (224) that meets the first outer surface (222b) or at the second connecting part (224) that meets the second outer surface (322b).

[0088] Since the first sealing jig (200) and the second sealing jig (300) are configured to be in close contact with each other when sealing a pouch-type battery cell, the bending angle of the first connecting part (224) meeting the first inner surface (222a) may be the same as the bending angle of the second connecting part (324) meeting the second inner surface (322a), and the bending angle of the first connecting part (224) meeting the first outer surface (222b) may be the same as the bending angle of the second connecting part (324) meeting the second outer surface (322b).

[0089] In the sealing device according to the first embodiment, the bending angle of the first connecting part (224) meeting the first inner surface (222a) is the same as the bending angle of the first connecting part (224) meeting the first outer surface (222b), and the bending angle of the second connecting part (324) meeting the second inner surface (322a) is the same as the bending angle of the second connecting part (324) meeting the second outer surface (322b).

[0090] The first bend portion (222) and the second bend portion (322) are located at parts corresponding to both ends of the outer periphery opposite to the gas discharge direction (G) in the pouch-type battery cell (100). However, in FIG. 7, they are shown to be placed only at the part corresponding to one end.

[0091] FIG. 8 is a perspective view of a portion of a pouch-type battery cell manufactured using the sealing device of FIG. 7.

[0092] Referring to FIG. 8 together with FIG. 7, the pouch-type battery cell (100) according to the present invention comprises an electrode assembly and a pouch-type battery case having an electrode assembly housing portion (120) for housing the electrode assembly, wherein the pouch-type battery case comprises a first case (101) and a second case (102) that are heat-fused to each other along the outer periphery, and a folded sealing portion (140) is formed at least one corner portion of the sealing portion where the first case (101) and the second case (102) are heat-fused.

[0093] The first case (101) and the second case (102) are formed as an integrated unit with overlapping outer edges by being folded along the folding line (124), and the folding sealing part (140) is formed adjacent to the folding line (124).

[0094] The first sealing portion (121) and the second sealing portion (122), formed to be perpendicular to the folding line (124), include a flat sealing portion (150) in a flat shape and a folded sealing portion (140) that is folded at an angle to the flat sealing portion (150). In this specification, the folded sealing portion (140) refers to a folded sealing portion formed at the corner of the sealing portion, and the flat sealing portion (150) refers to the sealing portion excluding the folded sealing portion (140).

[0095] As shown in FIG. 8(a), the boundary (160) between the folded sealing portion (140) and the flat sealing portion (150), which is the remaining unfolded sealing portion, may be formed in the shape of an angled corner. Alternatively, as shown in FIG. 8(b), the boundary (160) between the folded sealing portion (140) and the flat sealing portion (150), which is the remaining unfolded sealing portion, may be formed in the shape of a curved surface.

[0096] FIG. 9 is a perspective view of a sealing device according to a second embodiment placed in a pouch-type battery cell.

[0097] Referring to FIG. 9, only the first pressure part (220) of the first sealing jig (200) is shown, and only the second pressure part (320) of the second sealing jig (300) is shown.

[0098] In the first sealing jig (200), the first pressure portion (220) includes a first inner surface (222a) which is the outer periphery close to the pouch-type battery cell (100) and a second outer surface (222b) which is the opposite side of the first inner surface (222a), and the first bend portion (222) is configured such that the height of the first outer surface (H1b) is lower than the height (H1a) of the first inner surface.

[0099] In the second sealing jig (300), the second pressure portion (320) includes a second inner surface (322a) which is the outer periphery close to the pouch-type battery cell (100) and a second outer surface (322b) which is the opposite side of the second inner surface (322a), and the second bend portion (322) is configured such that the height of the second outer surface (H2b) is higher than the height of the second inner surface (H2a).

[0100] That is, in the first sealing jig (200) and the second sealing jig (300) illustrated in FIG. 9, when the first pressure surface (223) of the first planar portion (221) and the second pressure surface (323) of the second planar portion (321) are each in the xy plane, the first pressure surface (223) of the first bending portion (222) and the second pressure surface (323) of the second bending portion (322) are each bent by rotating along the y-axis with respect to the xy plane, and can also be bent by rotating clockwise along the x-axis toward the pouch-type battery cell.

[0101] Additionally, the first connecting part (224) and the second connecting part (324) may be parallel to the folding line (124) or parallel to the y-direction parallel to the length of the pouch-type battery cell.

[0102] Since the first sealing jig (200) and the second sealing jig (300) are configured to be in close contact with each other when sealing a pouch-type battery cell, the bending angle of the first connecting part (224) meeting the first inner surface (222a) may be the same as the bending angle of the second connecting part (324) meeting the second inner surface (322a), and the bending angle of the first connecting part (224) meeting the first outer surface (222b) may be the same as the bending angle of the second connecting part (324) meeting the second outer surface (322b).

[0103] In the sealing device according to the second embodiment, the bending angle of the first connecting part (224) meeting the first inner surface (222a) is smaller than the bending angle of the first connecting part (224) meeting the first outer surface (222b), and the bending angle of the second connecting part (324) meeting the second inner surface (322a) is smaller than the bending angle of the second connecting part (324) meeting the second outer surface (322b).

[0104] FIG. 10 is a perspective view and a partial enlarged view of a pouch-type battery cell manufactured using the sealing device of FIG. 9.

[0105] Referring to FIG. 10, in a pouch-type battery cell, the fold sealing portion (140) includes an inner portion (141) adjacent to the electrode assembly housing portion (120) and an outer portion (142) opposite to the inner portion (141), and is formed in a shape in which the outer portion (142) is folded further toward the first case (101) than the inner portion (141).

[0106] FIG. 11 is a perspective view of a sealing device according to the third embodiment placed in a pouch-type battery cell.

[0107] Referring to FIG. 11, a pouch-type battery cell (100) is placed between the first sealing jig (200) and the second sealing jig (300).

[0108] FIG. 11 shows only the first pressure part (220) of the first sealing jig (200) and only the second pressure part (320) of the second sealing jig (300).

[0109] The sealing device according to the third embodiment is identical to the sealing device according to the second embodiment in that the heights of the first inner surface (222a) and the first outer surface (222b) in the first bending portion (222) of the first pressing portion (220) are different, and the heights of the second inner surface (322a) and the second outer surface (322b) in the second bending portion (324) of the second pressing portion (320) are different, but the first connecting portion (224) and the second connecting portion (324) are provided at an angle inclined with respect to the y-direction parallel to the length of the folding line (124) or the pouch-type battery cell.

[0110] FIG. 12 is a perspective view of a pouch-type battery cell manufactured using the sealing device of FIG. 11.

[0111] Referring to FIG. 12, the fold sealing portion (140) includes an inner portion (141) adjacent to the electrode assembly housing portion (120) and an outer portion (142) opposite to the inner portion (141), and the inner portion (141) is in contact with the folding line (124), while the outer portion (142) is folded further toward the flat sealing portion (150) than the folding line (124).

[0112] In such cases, even if the size of the deformation portion of the pouch-type battery cell is small, the bending sealing portion can be formed more easily at the corner portion, and the length of the pouch-type battery cell in the x-direction can be effectively reduced.

[0113]

[0114] In this way, the present invention provides a sealing device including a folding portion and a pouch-type battery cell including a folding sealing portion, thereby reducing the deformation portion (130) that extends further outward from the folding line in the pouch-type battery cell and improving the dimensional safety of the pouch-type battery cell, which can lower the rate of defective battery cell occurrence.

[0115]

[0116] A person skilled in the art to which the present invention pertains would be able to perform various applications and modifications within the scope of the present invention based on the above content.

[0117] (Explanation of symbols)

[0118] 100: Pouch-type battery cell

[0119] 101: Case 1

[0120] 102: Case 2

[0121] 111: Positive lead

[0122] 112: Cathode lead

[0123] 120: Electrode assembly housing

[0124] 121: First sealing section

[0125] 122: Second sealing section

[0126] 123: Third sealing part

[0127] 124: Folding Line

[0128] 130: Transformation part

[0129] 140: Bending sealing part

[0130] 141: Medial part

[0131] 142: Lateral part

[0132] 150: Flat sealing part

[0133] 160: Boundary

[0134] 200: 1st sealing jig

[0135] 210: First main body part

[0136] 220: First pressurizing unit

[0137] 221: First plane section

[0138] 222: First bend

[0139] 222a: First inner surface

[0140] 222b: First outer surface

[0141] 223: First pressurized surface

[0142] 224: First connection part

[0143] 230: Pressurized surface

[0144] 300: 2nd sealing jig

[0145] 310: Second main body part

[0146] 320: Second pressurizing unit

[0147] 321: Second plane

[0148] 322: Second bend

[0149] 322a: Second inner surface

[0150] 322b: Second outer surface

[0151] 323: Second pressurized surface

[0152] 324: Second connection part

[0153]

[0154] A: Area 1

[0155] B: Area 2

Claims

1. A first sealing jig for pressing a first surface of a pouch-type battery cell, and a second sealing jig for pressing a second surface of the pouch-type battery cell, and The above-mentioned first sealing jig and the above-mentioned second sealing jig are, A sealing device comprising a flat portion having a flat surface for applying pressure, and a bent portion having one end of the flat portion, which is bent to be inclined at a certain angle to the flat portion.

2. In Paragraph 1, The above-mentioned first sealing jig is, It includes a first pressure part in which a first planar part and a first bending part are continuously arranged, and a first main body part for supporting the first pressure part and fixing it to a pressure device, The above second sealing jig is, A sealing device comprising a second pressure portion in which a second planar portion and a second bending portion are continuously arranged, and a second main body portion for supporting the second pressure portion and fixing it to a pressure device.

3. In Paragraph 2, In the first sealing jig above, the first pressure surface of the first planar portion is parallel to the first surface of the pouch-type battery cell, and the first bend portion is bent toward the first main body portion with respect to the first pressure surface. A sealing device in which, in the second sealing jig above, the second pressure surface of the second planar portion is parallel to the second surface of the pouch-type battery cell, and the second bend portion is bent so as to be away from the second main body portion with respect to the second pressure surface.

4. In Paragraph 3, A sealing device in which the bending angle of the first connecting part and the bending angle of the second connecting part are configured to be the same.

5. In Paragraph 3, A sealing device in which the bending angle of the first bending portion and the bending angle of the second bending portion are formed to be greater than 0° and less than or equal to 90°.

6. In Paragraph 5, A sealing device in which the bending angle of the first bending portion and the bending angle of the second bending portion are formed to be 10° or more and 45° or less.

7. In Paragraph 1, A sealing device in which the connecting portion connecting the above-mentioned flat portion and the above-mentioned bent portion is formed as a curved surface.

8. In Paragraph 3, In the first sealing jig above, the first pressing part includes a first inner surface which is an outer surface close to the pouch-type battery cell and a second outer surface which is opposite to the first inner surface, and The first bend portion is configured such that the height of the first outer surface is lower than the height of the first inner surface, and In the second sealing jig above, the second pressing part includes a second inner surface which is an outer surface close to the pouch-type battery cell and a second outer surface which is opposite to the second inner surface, and A sealing device in which the second bend portion is configured such that the height of the second outer surface is higher than the height of the second inner surface.

9. In Paragraph 1, The above-mentioned bending portion is a sealing device located at a portion corresponding to both ends of the outer periphery opposite to the gas discharge direction in the pouch-type battery cell.

10. Includes an electrode assembly and a pouch-type battery case that accommodates the electrode assembly, and The above pouch-type battery case includes a first case and a second case that are heat-fused to each other along the outer periphery, and A pouch-type battery cell in which a folded sealing portion is formed at least one corner portion of the sealing portion in which the first case and the second case are heat-fused.

11. In Paragraph 10, The first case and the second case are formed as an integrated unit that is folded along a folding line and has its outer periphery heat-fused. The above-mentioned folding sealing portion is a pouch-type battery cell formed adjacent to the above-mentioned folding line.

12. In Paragraph 10, A pouch-type battery cell in which the boundary between the above-mentioned folded sealing portion and the flat sealing portion, which is the remaining unfolded sealing portion, is formed in the shape of an angled corner.

13. In Paragraph 10, A pouch-type battery cell in which the boundary between the above-mentioned folded sealing portion and the flat sealing portion, which is the remaining unfolded sealing portion, is formed in a curved shape.

14. In Paragraph 10, The above-mentioned bending sealing portion includes an inner portion adjacent to the electrode assembly housing portion and an outer portion opposite to the inner portion, and A pouch-type battery cell formed such that the outer portion is folded further toward the first case than the inner portion.

15. In Paragraph 12, A pouch-type battery cell in which the boundary between the above-mentioned folded sealing portion and the above-mentioned flat sealing portion is formed parallel to the folding line.

16. In Paragraph 12, A pouch-type battery cell in which the boundary between the above-mentioned folded sealing portion and the above-mentioned flat sealing portion is formed in a shape inclined with respect to the extension of the folding line.

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