Molding apparatus and molding method, and pouch-type battery case molded by same

Abstract

The molding apparatus according to an embodiment of the present invention can mold a soft envelope. The molding apparatus may include: a mold in which a first opening is defined; the demolding device is arranged above the mold to fix the soft wrapping film and is provided with a second opening; a sub-mold having a height that is variable relative to the mold inside the first opening; a punch configured to press the soft envelope through the second opening and disposed to face the sub-mold; and a sub-punch configured to press the soft envelope between the inner periphery of the first opening and the outer periphery of the sub-mold through a space between the inner periphery of the second opening and the outer periphery of the punch.

Description

Technical Field

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of priority of Korean Patent Application No. 10 - 2022 - 0136748, filed on October 21, 2022, which is incorporated herein by reference in its entirety. Technical Field

[0004] The present invention relates to a molding device and a molding method for molding a soft package film and a soft - package type battery case molded thereby. Background Art

[0005] Generally, secondary batteries include nickel - cadmium batteries, nickel - metal hydride batteries, lithium - ion batteries, and lithium - ion polymer batteries. Such secondary batteries are being applied to small products such as digital cameras, P - DVDs, MP3Ps, mobile phones, PDAs, portable game devices, power tools, electric bicycles, etc., large products that require high power such as electric vehicles and hybrid vehicles, power storage devices for storing surplus power or renewable energy, and backup power storage devices.

[0006] Generally, in order to manufacture a secondary battery, first, an electrode active material slurry is coated on a positive electrode current collector and a negative electrode current collector to manufacture a positive electrode and a negative electrode. Then, the electrodes are laminated on both sides of a separator to form an electrode assembly. In addition, the electrode assembly is accommodated in a battery case, and then, after injecting an electrolyte therein, the battery case is sealed.

[0007] According to the material of the case that houses the electrode assembly, such secondary batteries are classified into soft - package type secondary batteries and can - type secondary batteries. In a soft - package type secondary battery, the electrode assembly is accommodated in a soft package made of a flexible polymer material. In addition, in a can - type secondary battery, the electrode assembly is accommodated in a case made of a metal material or a plastic material.

[0008] Generally, a soft - package type battery case is manufactured by performing a pressing process on a flexible soft - package film to form a cup part. Additionally, when forming the cup part, the electrode assembly is accommodated in the cup part, and then, the side part of the cup part is sealed to manufacture a secondary battery.

[0009] Generally, in the pressing process, stretch forming is performed by inserting the soft - package film between a mold and a stripper and applying pressure to the soft - package film using a punch to stretch the soft - package film.

[0010] However, in the method according to the related art, when molding the cup part, there is a risk of cracks appearing in the soft - package film, and there is a limit to the increase in the depth of the cup part. Summary of the Invention

[0011] Technical Problem

[0012] An object of the present invention is to provide a molding apparatus and a molding method capable of molding a cup portion deeper in a soft film package by dividing a molding process into multiple times.

[0013] Another object of the present invention is to provide a soft package type battery case manufactured by the molding apparatus or the molding method.

[0014] Technical Solution

[0015] A molding apparatus according to an embodiment of the present invention can mold a soft film package. The molding apparatus may include: a mold in which a first opening is defined; a stripper disposed above the mold to fix the soft film package and having a second opening; a sub-mold having a height variable relative to the mold inside the first opening; a punch configured to press the soft film package through the second opening and disposed to face the sub-mold; and a sub-punch configured to press the soft film package located between the inner periphery of the first opening and the outer periphery of the sub-mold through a space between the inner periphery of the second opening and the outer periphery of the punch.

[0016] The sub-punch may be configured to press the soft film package once in a state where the top surface of the sub-mold and the top surface of the mold are disposed on the same plane, and the punch and the sub-punch may be configured to press the soft film package twice in a state where the top surface of the sub-mold is disposed below the top surface of the mold.

[0017] The sub-punch may be disposed to surround the outer periphery of the punch.

[0018] A protrusion protruding from the inner periphery of the first opening toward the outer periphery of the sub-mold and overlapping with the sub-punch in the vertical direction may be provided on the mold.

[0019] A molding apparatus according to an embodiment of the present invention can perform molding of a soft film package. The molding method may include: fixing the soft film package between a mold forming a first opening and a stripper forming a second opening; causing the sub-punch to press the soft film package once through the second opening between the outer periphery of the sub-mold disposed in the first opening and the inner periphery of the first opening; and causing the punch disposed to face the sub-mold with the soft film package interposed therebetween and the sub-punch to press the soft film package twice through the second opening toward the first opening.

[0020] In the fixing and / or the first pressing, the top surface of the sub-mold may be disposed on the same plane as the top surface of the mold.

[0021] In the fixing and / or the first pressing, the soft film package may be fixed between the sub-mold and the punch.

[0022] In the second pressing, the bottom surface of the punch may be disposed on the same plane as the bottom surface of the sub-punch.

[0023] In one pressing, the sub-punch can mold a recess with a first depth in the soft packaging film, and in a second pressing, the punch and the sub-punch can mold a cup portion with a second depth deeper than the first depth in the soft packaging film.

[0024] In the second pressing, the recess can be expanded to be molded into a cup portion.

[0025] A protrusion protruding from the inner periphery of the first opening toward the outer periphery of the sub-mold can be formed on the mold. In the second pressing, the sub-punch can press the soft packaging film to a depth at which the soft packaging film contacts the protrusion.

[0026] In the second pressing, the top surface of the sub-mold can be disposed on the same plane as the top surface of the protrusion.

[0027] The soft package type battery case according to an embodiment of the present invention may include: a cup portion having a concave shape; and a platform disposed on the periphery of the cup portion. The peripheral portion of the cup portion may include: a first peripheral portion connected to the platform through a mold edge; and a second peripheral portion connected to the first peripheral portion and having a thickness smaller than the thickness of the first peripheral portion.

[0028] The bottom of the cup portion may include: a first bottom disposed at its center; and a second bottom having a thickness smaller than the thickness of the first bottom and connected to the peripheral portion of the cup portion through a stamping edge.

[0029] The thickness of the second peripheral portion may be smaller than the thickness of the second bottom.

[0030] The thickness of the first peripheral portion may be smaller than the thickness of the first bottom.

[0031] The thickness of the stamping edge connecting the second peripheral portion and the second bottom may be the same as the thickness of the second bottom or the second peripheral portion.

[0032] The thickness of the stamping edge connecting the second peripheral portion and the second bottom may be the same as the thickness of the second peripheral portion and smaller than the thickness of the second bottom.

[0033] The thickness of the stamping edge connecting the second peripheral portion and the second bottom may be the same as the thickness of the second bottom and greater than the thickness of the second peripheral portion.

[0034] The peripheral portion of the cup portion may further include a third peripheral portion connected to the second peripheral portion and having a thickness greater than the thickness of the second peripheral portion. The thickness of the stamping edge connecting the third peripheral portion and the second bottom may be the same as the thickness of each of the third peripheral portion and the second bottom and greater than the thickness of the second peripheral portion.

[0035] Advantageous Effects

[0036] According to a preferred embodiment of the present invention, a deeper cup portion can be molded without cracks occurring in the soft film envelope. More specifically, according to the related art, since the cup portion is molded by a single press, only a specific area of the soft film envelope is overstretched, so the depth of the cup portion may be limited to prevent cracks. On the other hand, in the present invention, since the molding process is performed several times, the areas of the soft film envelope that were not stretched in the related art are also stretched, and the advantage is that the cup portion can be molded deeper.

[0037] In addition, effects that are obvious to those skilled in the art can be predicted from the configuration of the embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The following drawings attached to this specification illustrate preferred embodiments of the present invention and are used to further understand the technical concept of the present invention and the specific implementation manners of the present invention. Therefore, the present invention should not be construed as being limited to the drawings.

[0039] Figure 1 is a schematic diagram of a molding device according to an embodiment of the present invention.

[0040] Figures 2 to 5 is a schematic diagram continuously showing the operation of a molding device according to an embodiment of the present invention.

[0041] Figure 6 is a flowchart of a molding method according to another embodiment of the present invention.

[0042] Figure 7 is a schematic diagram showing the manufacturing process of a soft-pack type battery case according to still another embodiment of the present invention.

[0043] Figure 8 is a cross-sectional view of a soft-pack type secondary battery according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0044] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention can be implemented in several different forms and is not limited or restricted by the following examples.

[0045] To clearly describe the present invention, detailed descriptions of parts that are not related to the description or related known technologies and may unnecessarily obscure the key points of the present invention have been omitted, and reference numerals are added to the components in each of the drawings in this specification. In this case, throughout the specification, the same or similar reference numerals denote the same or similar elements.

[0046] In addition, the terms or words used in the specification and claims should not be construed restrictively in accordance with their ordinary or dictionary meanings, but rather, based on the principle that the inventor can appropriately define the concepts of the terms, should be construed to have meanings and concepts that conform to the scope of the present invention, so as to describe and explain his or her invention in the best manner.

[0047] Figure 1 is a schematic view of a molding device according to an embodiment of the present invention, and Figures 2 to 5 is a schematic view successively showing the operation of a molding device according to an embodiment of the present invention.

[0048] A molding device according to an embodiment of the present invention can mold a soft packaging film 100. The soft packaging film 100 can have a predetermined thickness. The soft packaging film 100 can be a laminated sheet having formability. More specifically, the soft packaging film 100 can be a laminated sheet in which a pair of resin layers are laminated at two outermost surfaces and a metal layer is provided between the pair of resin layers.

[0049] A molding device according to an embodiment of the present invention can include a mold 10, a stripper 20, a sub-mold 30, a punch 40, and a sub-punch 50.

[0050] Some of the mold 10, the stripper 20, the sub-mold 30, the punch 40, and the sub-punch 50 can be configured to rise relative to other components. For example, any one of the mold 10, the stripper 20, the sub-mold 30, the punch 40, and the sub-punch 50 can be fixed, and the other components can be configured to rise independently of any one component. As another example, each of the mold 10, the stripper 20, the sub-mold 30, the punch 40, and the sub-punch 50 can be configured to rise independently.

[0051] The mold 10 can be provided below the soft packaging film 100. A first opening 12 can be defined in the mold 10. The first opening 12 can be defined downward from the top surface of the mold 10. The first opening 12 can be a molding space in which the soft packaging film 100 is recessed. In addition, the first opening 12 can be a space in which the sub-mold 30 described later is provided.

[0052] The cross-section of the first opening 12 can be generally square, but is not limited thereto.

[0053] A rounded edge 11 can be defined on the mold 10. More specifically, the top surface of the mold 10 and the inner circumference of the first opening 12 can be connected to each other by the rounded edge 11. The edge 11 can have a predetermined radius of curvature. The edge 11 can be provided in a circular shape to prevent the portion in close contact with the edge 11 from breaking when the soft packaging film 100 is stretched into the first opening 12.

[0054] On the mold 10, a protrusion 14 that protrudes inward from the inner periphery of the first opening 12 can be provided. The protrusion 14 can protrude toward the outer periphery of the sub-mold 30.

[0055] The protrusion 14 can overlap with the sub-punch 50 in a direction perpendicular to the sub-punch 50, which will be described later. Therefore, the protrusion 14 can be used as a stopper that restricts the descent of the sub-punch 50.

[0056] The protrusion 14 can be provided at a position spaced downward from the top surface of the mold 10 by a predetermined distance. As Figure 1 shown, the mold 10 can include a lower body that defines the protrusion 14 inside thereof and an upper body that is provided on the upper side of the lower body and contacts the soft film 100. However, it is not limited thereto, and the configuration of the mold can be changed as needed. For example, the mold 10 can be provided integrally.

[0057] The stripper 20 can face the mold 10, and the soft film 100 is located between the stripper 20 and the mold 10. The stripper 20 can fix the soft film 100 on the upper side of the mold 10.

[0058] More specifically, at least one of the mold 10 or the stripper 20 can be configured to rise, and the gap between the mold 10 and the stripper 20 can be variable. When the mold 10 and the stripper 20 are spaced apart from each other, the soft film 100 can be inserted between the mold 10 and the stripper 20, and then when the mold 10 and the stripper 20 approach each other, the soft film 100 can be fixed between the mold 10 and the stripper 20. That is, the soft film 100 can be fixed between the top surface of the mold 10 and the bottom surface of the stripper 20.

[0059] A second opening 22 can be defined in the stripper 20. The second opening 22 can be defined to penetrate upward from the bottom surface of the stripper 20. The second opening 22 can be a space for setting a punch 40 and a sub-punch 50, which will be described later.

[0060] The cross-section of the second opening 22 can be generally square, but it is not limited thereto. The second opening 22 can be provided above the first opening 12. The second opening 22 and the first opening 12 can face each other, and the soft film 100 is located between them.

[0061] The height of the sub-mold 30 relative to the mold 10 within the first opening 12 can be variable. More specifically, at least one of the mold 10 or the sub-mold 30 can be configured to rise, and the height difference between the top surface of the mold 10 and the top surface of the sub-mold 30 can be variable.

[0062] A rounded edge 31 can be provided on the sub-mold 30. More specifically, the top surface and the outer periphery of the sub-mold 30 can be connected to each other by the rounded edge 31. The edge 31 can have a predetermined radius of curvature. The edge 31 can be set to be circular to prevent the portion in close contact with the edge 31 from breaking when the soft film envelope 100 is stretched into the first opening 12.

[0063] Referring to Figure 2 and Figure 3 , in a primary molding where the sub-punch 50 presses the soft film envelope 100, the sub-mold 30 can fix the soft film envelope 100 together with the punch 40. More specifically, when the sub-punch 50 presses the soft film envelope 100, the central portion of the soft film envelope 100 can be fixed between the bottom surface of the punch 40 and the top surface of the sub-mold 30.

[0064] Referring to Figure 4 and Figure 5 , in a secondary molding where the punch 40 and the sub-punch 50 are pressed together to press the soft film envelope 100, the top surface of the sub-mold 30 can be disposed below the top surface of the mold 10. More specifically, when the punch 40 and the sub-punch 50 press the soft film envelope 100 together, the top surface of the sub-mold 30 can be disposed on the same plane as the top surface of the protrusion 14. Here, the sub-mold 30 can be used as a stopper to limit the descent of the punch 40.

[0065] The punch 40 can press the soft film envelope 100 through the second opening 22. The height of the punch 40 relative to the sub-mold 30 within the second opening 22 can be variable. More specifically, at least one of the punch 40 and the sub-mold 30 can be configured to rise, and the height difference between the bottom surface of the punch 40 and the top surface of the sub-mold 30 can be variable.

[0066] A rounded edge 41 can be provided on the punch 40. More specifically, the outer periphery and the bottom surface of the punch 40 can be connected to each other by the rounded edge 41. The edge 41 can have a predetermined radius of curvature. The edge 41 can be set to be circular to prevent the portion in close contact with the edge 41 from breaking when the punch 40 presses the soft film envelope 100.

[0067] As described above, in the primary molding, the punch 40 can fix the soft film envelope 100 together with the sub-mold 30, and in the secondary molding, the punch 40 can press the soft film envelope 100 together with the sub-punch 50. More specifically, the punch 40 can press the soft film envelope 100 while descending toward the sub-mold 30.

[0068] The sub-punch 50 can press the soft film envelope 100 through the second opening 22. More specifically, the sub-punch 50 can press the soft film envelope 100 between the inner periphery of the first opening 12 and the outer periphery of the sub-mold 30 through the space between the inner periphery of the second opening 22 and the outer periphery of the punch 40.

[0069] The sub-punch 50 can face the protrusion 14 of the mold 10 in the vertical direction. The sub-punch 50 can be arranged around the outer periphery of the punch 40. The sub-punch 50 can be arranged between the outer periphery of the punch 40 and the inner periphery of the second opening 22. That is, the outer periphery of the sub-punch 50 can face the inner periphery of the second opening 22, and the inner periphery of the sub-punch 50 can face the outer periphery of the punch 40.

[0070] The sub-punch 50 can rise independently of the punch 40. The height of the sub-punch 50 relative to the mold 10 within the second opening 22 can be variable. More specifically, at least one of the sub-punch 50 and the mold 10 can be configured to rise, and the height difference between the bottom surface of the sub-punch 50 and the top surface of the mold 10 can be variable.

[0071] A rounded edge 51 can be provided on the sub-punch 50. More specifically, the outer and inner peripheries of the sub-punch 50 can be connected to the bottom surface by rounded edges 45. The edge 51 can have a predetermined radius of curvature. Alternatively, the bottom surface of the sub-punch 50 can be arranged to be circular. Thus, when the sub-punch 50 presses the soft film package 100, the part of the soft film package 100 in close contact with the edge 51 or the bottom surface of the sub-punch 50 can be prevented from cracking.

[0072] In a first molding, the sub-punch 50 can mold the soft film package 100 to a first depth d1. In a second molding, the punch 40 and the sub-punch 50 can mold the soft film package 100 to a second depth d2 greater than the first depth d1.

[0073] Hereinafter, the operation of the molding device according to an embodiment of the present invention will be described. In addition, for convenience of explanation, hereinafter, the case where the mold 10 is fixed and each of the ejector 20, the sub-mold 30, the punch 40, and the sub-punch 50 rises independently will be described as an example.

[0074] Refer to Figure 1 , in a state where the soft film package 100 enters between the mold 10 and the ejector 20, the ejector 20 descends toward the mold 10, and a part of the outer side of the soft film package 100 can be fixed between the ejector 20 and the mold 10. In addition, the punch 40 can descend toward the sub-mold 30, so that a part inside the soft film package 100 can be fixed between the punch 40 and the sub-mold 30. Here, the top surface of the mold 10 and the top surface of the sub-mold 30 can be arranged on the same horizontal plane, and the bottom surface of the punch 40 and the bottom surface of the ejector 20 can be arranged on the same horizontal plane. Therefore, the soft film package 100 can be fixed while maintaining its flat state as much as possible.

[0075] Refer to Figure 2, the sub-punch 50 can press the flexible packaging film 100 between the inner circumference of the first opening 12 and the outer circumference of the sub-mold 30 through the space between the inner circumference of the second opening 22 and the outer circumference of the punch 40. This can be referred to as primary molding, and a recessed portion 110 can be defined in the flexible packaging film 100 through primary molding. The recessed portion 110 can have a first depth d1.

[0076] After that, referring to Figure 3 , the sub-mold 30 can be lowered. Accordingly, the portion of the flexible packaging film 100 fixed between the sub-mold 30 and the punch 40 can be released. More specifically, the sub-mold 30 can be lowered such that the top surface of the sub-mold 30 and the top surface of the protrusion 14 are disposed on the same horizontal plane. In addition, the sub-punch 50 can be raised. More specifically, the sub-punch 50 can be raised such that the bottom surface of the sub-punch 50 and the bottom surface of the punch 40 are disposed on the same horizontal plane.

[0077] After that, referring to Figure 4 , the punch 40 and the sub-punch 50 can be lowered together to press the flexible packaging film 100. Here, the sub-punch 50 can press the flexible packaging film 100 to the depth at which the flexible packaging film 100 contacts the protrusion 14, and the punch 40 can press the flexible packaging film 100 to the depth at which the flexible packaging film 100 contacts the sub-mold 30.

[0078] This can be referred to as secondary molding, and the recessed portion 110 previously molded in the flexible packaging film 100 can be expanded through secondary molding to mold the cup portion 120. The second depth d2 of the cup portion 120 can be greater than the first depth d1 of the recessed portion 110.

[0079] After that, referring to Figure 5 , the punch 40 and the sub-punch 50 can be raised to return to their initial positions. In addition, although not shown in the figure, the ejector 20 can also be raised, and the flexible packaging film 100 fixed between the mold 10 and the ejector 20 can be released.

[0080] Due to this series of processes, the molding of the cup portion 120 on the flexible packaging film 100 can be completed. In the related art, the cup portion is molded by a single pressing, but in this case, only a specific area of the flexible packaging film is overstretched, so the depth of the cup portion is limited to prevent cracks. On the other hand, in the present invention, since the flexible packaging film 100 is molded multiple times, the areas of the flexible packaging film that are not stretched in the related art are also stretched, having the advantage that the cup portion 120 can be molded deeper.

[0081] Figure 6 is a flowchart of a molding method according to another embodiment of the present invention.

[0082] Hereinafter, a molding method of molding the flexible packaging film 100 using the above molding device will be described as another embodiment of the present invention.

[0083] The molding method according to another embodiment of the present invention may include a process of fixing the flexible packaging film 10 between the mold 10 and the stripper 20 (S10) (hereinafter referred to as the "fixing process"); a process of pressing the flexible packaging film 100 once between the outer periphery of the sub-punch 50 and the inner periphery of the first opening 12 in the sub-mold 30 (S20) (hereinafter referred to as the "primary molding process"), and a process of pressing the flexible packaging film 100 a second time together with the punch 40 and the sub-punch 50 (S30) (hereinafter referred to as the "secondary molding process").

[0084] In each of the processes (S10, S20, and S30), the foregoing description of the operation of the molding equipment may be referred to. More specifically, for the fixing process (S10), reference may be made to the content described with reference to Figure 1 For the primary molding process (S20), reference may be made to the content described with reference to Figure 2 and Figure 3 For the secondary molding process (S30), reference may be made to the content described with reference to Figure 4 and Figure 5 The content described. Hereinafter, the main features will be briefly described.

[0085] In the fixing process (S10) and / or the primary molding process (S20), the top surface of the sub-mold 30 may be disposed on the same plane as the top surface of the mold 10. In the fixing process (S10) and / or the primary molding process (S20), the flexible packaging film 100 may be fixed between the sub-mold 30 and the punch 40.

[0086] In the primary molding process (S20), the sub-punch 50 may mold a recessed portion 110 having a first depth d1 in the flexible packaging film 100.

[0087] In the secondary molding process (S30), the punch 40 and the sub-punch 50 may mold a cup portion 120 having a second depth d2 greater than the first depth d1 in the flexible packaging film 100. In the secondary molding process (S30), the recessed portion 110 may be expanded and molded into the cup portion 120. In the secondary molding process (S30), the sub-punch 50 may press the flexible packaging film 100 to a depth at which the flexible packaging film 100 contacts the protruding portion 14.

[0088] In the secondary molding process (S30), the bottom surface of the punch 40 may be disposed on the same plane as the bottom surface of the sub-punch 50. In the secondary molding process (S30), the top surface of the sub-mold 30 may be disposed on the same plane as the top surface of the protruding portion 14.

[0089] Figure 7 is a schematic view showing the manufacturing process of a flexible package type battery case according to still another embodiment of the present invention, and Figure 8is a cross-sectional view of a pouch-type secondary battery according to an embodiment of the present invention. In Figure 7 the solid line represents the recessed portion 110, and the dashed line represents the cup portion 120.

[0090] Hereinafter, a pouch-type battery case manufactured by the above molding device or molding method will be described as another embodiment of the present invention.

[0091] A pouch-type battery case (hereinafter referred to as "battery case") according to another embodiment of the present invention may include a cup portion 120 having a recessed shape and a platform 130 provided to surround the cup portion 120.

[0092] The cup portion 120 may define a space for accommodating an electrode assembly (not shown). The platform 130 may be a portion of the pouch film 100 fixed between the mold 10 and the stripper 20 and in which the cup portion 120 is not molded.

[0093] In the manufacturing process of the battery case, the recessed portion 110 may be molded once, the recessed portion 110 may be expanded, and the cup portion 120 having a depth deeper than that of the recessed portion 110 may be molded twice.

[0094] The recessed portion 110 may include an outer peripheral portion 112, an inner peripheral portion 113, and a connecting portion 114.

[0095] The outer peripheral portion 112 may be connected to the platform 130 through a mold edge 111. The mold edge 111 may be formed in a circular shape. More specifically, the mold edge 111 may have a predetermined radius of curvature. The mold edge 111 may be formed by the edge 11 of the mold 10 (see Figure 1 ) and may have a radius of curvature corresponding to that of the edge 11 of the mold 10.

[0096] The inner peripheral portion 113 may be connected to the central portion 101 through a connecting edge 115. The central portion 101 may be a portion of the pouch film 100 fixed between the punch 40 and the sub-mold 30 during the first molding and in which the recessed portion 110 is not formed. The connecting edge 115 may be formed in a circular shape. More specifically, the connecting edge 115 may have a predetermined radius of curvature. The connecting edge 115 may be formed by the edge 31 of the sub-mold 30 (see Figure 1 ) and may have a radius of curvature corresponding to that of the edge 31 of the sub-mold 30.

[0097] The connecting portion 114 may connect the outer peripheral portion 112 to the inner peripheral portion 113. The shape of the connecting portion 114 may correspond to the shape of the bottom surface of the sub-punch 50.

[0098] In the first molding of the soft film package 100, the platform 130 and the central portion 101 may not be stretched, so the remaining thickness may be relatively thick and may be the same as the thickness of the soft film package 100.

[0099] Since the connecting portion 114 is directly pressed by the auxiliary punch 50, the connecting portion 114 can be relatively stretched and its remaining thickness can be thinned. In addition, the outer peripheral portion 112 and the inner peripheral portion 113 can be stretched relatively less than the connecting portion 114. The die edge 111 and the connecting edge 115 can also be stretched to the same or similar extent as each of the outer peripheral portion 112 and the inner peripheral portion 113.

[0100] Therefore, the thickness of each of the outer peripheral portion 112, the inner peripheral portion 113, the die edge 111 and the connecting edge 115 can be greater than the thickness of the connecting portion 114 and can be less than the thickness of each of the platform 130 and the central portion 101.

[0101] In the second molding of the soft film package 100, the outer peripheral portion 112 of the recessed portion 110 can form the first peripheral portion 122a of the peripheral portion 122 of the cup portion 120. In addition, the connecting portion 114, the inner peripheral portion 113, the connecting edge 115 and the central portion 101 of the recessed portion 110 can form the second peripheral portion 122b, the bottom 121 and the stamping edge 123 of the other parts of the peripheral portion of the cup portion 120.

[0102] Therefore, based on Figure 7 the cross-sectional view shown in 1 , in the recessed portion 110, the length of the connecting portion 114 is L 2 , the length of the inner peripheral portion 113 is L 3 , the length of the connecting edge 115 is L 4 , and the length of the central portion 101 is L 5 , and in the cup portion 120, the length of the second peripheral portion 122b is L 6 , the length of the stamping edge 123 is L 7 , and the length of the bottom 121 is L 1 +L 2 +L 3 )+L 2 =2*(L 5 +L 7 )+L 6 .

[0103] The reference numeral L 1 as the length of the connecting portion 114 can refer to the length from the boundary P1 between the outer peripheral portion 112 and the connecting portion 114 to the boundary P2 between the connecting portion 114 and the inner peripheral portion 113. The reference numeral L 2It may refer to the length from the boundary P2 between the connecting portion 114 and the inner peripheral portion 113 to the boundary P3 between the inner peripheral portion 113 and the connecting edge 115. The reference numeral L for the length of the connecting edge 115 3 It may refer to the length from the boundary P3 between the inner peripheral portion 113 and the connecting edge 115 to the boundary P4 between the connecting edge 115 and the central portion 101. The reference numeral L for the length of the central portion 101 4 It may refer to the length between the boundaries between the two connecting edges 115 and the central portion 101. The reference numeral L for the length of the second peripheral portion 122b 5 It may refer to the distance from the boundary P1 between the outer peripheral portion 112 and the connecting portion 114 to the boundary P5 between the second peripheral portion 122b and the stamping edge 123. The reference numeral L for the length of the stamping edge 123 6 It may refer to the distance from the boundary P5 between the second peripheral portion 122b and the stamping edge 123 to the boundary P6 between the stamping edge 123 and the bottom 121. The reference numeral L for the length of the bottom 121 7 It may refer to the length between the boundaries P6 between the two stamping edges 123 and the bottom 121.

[0104] Since the recessed portion 110 is expanded to form the cup portion 120, the thickness of each part of the cup portion 120 may be different from the thickness of the cup portion formed by the conventional method. Hereinafter, reference will be made to Figure 7 and Figure 8 to describe the cup portion 120.

[0105] The cup portion 120 may include a bottom 121 and a peripheral portion 122.

[0106] The peripheral portion 122 of the cup portion 120 may be connected to the platform 130 and the die edge 111. The die edge 111 may maintain the state that has been formed when it held the recessed portion 110 before molding.

[0107] The bottom 121 of the cup portion 120 may be connected to the peripheral portion 122 and the stamping edge 123. The stamping edge 123 may be formed into a circular shape. More specifically, the stamping edge 123 may have a predetermined radius of curvature. The stamping edge 123 may be formed by the edge 51 of the sub-punch 50 (see Figure 1 ) and may have a radius of curvature corresponding to the radius of curvature of the edge 51 of the sub-punch 50.

[0108] The peripheral portion 122 of the cup portion 120 may include a first peripheral portion 122a connected to the platform 130 through the die edge 111 and a second peripheral portion 122b connected to the bottom 121 through the stamping edge 123 and having a thickness smaller than the thickness of the first peripheral portion 122a.

[0109] The first peripheral portion 122a can correspond to the outer peripheral portion 112 of the recessed portion 110, and the second peripheral portion 122b can correspond to the connecting portion 114 of the recessed portion 110. That is to say, the outer peripheral portion 112 can form the first peripheral portion 122a, and the connecting portion 114 can be unfolded to form the second peripheral portion 122b. As described above, the remaining thickness of the connecting portion 114 can be less than the remaining thickness of the outer peripheral portion 112, so the thickness t2 of the second peripheral portion 122b can be relatively less than the thickness of the first peripheral portion 122a.

[0110] The bottom 121 of the cup portion 120 can include a first bottom 121a provided at its center and a second bottom 121b having a thickness smaller than that of the first bottom 121a and connected to the peripheral portion 122 through a stamping edge 123.

[0111] The first bottom 121a can correspond to the central portion 101, and the second bottom 121b can correspond to the inner peripheral portion 113 and the connecting edge 115 of the recessed portion 110. That is to say, the central portion 101 can form the first bottom 121a, and the inner peripheral portion 113 and the connecting edge 115 can be unfolded to form the second bottom 121b. As described above, the remaining thickness of each of the inner peripheral portion 113 and the connecting edge 115 can be less than the remaining thickness of the central portion 101, so the thickness t4 of the second bottom 121b can be relatively less than the thickness of the first bottom 121a.

[0112] In addition, the thickness t2 of the second peripheral portion 122b can be less than the thickness of the second bottom 121b. As described above, this is because the remaining thickness of the connecting portion 114 is less than the remaining thickness of each of the inner peripheral portion 113 and the connecting edge 115.

[0113] In addition, the thickness t1 of the first peripheral portion 122a can be less than the thickness t3 of the first bottom 121a. As described above, this is because the remaining thickness of the outer peripheral portion 112 is less than the remaining thickness of the central portion 101.

[0114] The thickness of the stamping edge 123 can vary according to the length ratio of the connecting portion 114 to the inner peripheral portion 113, because the connecting portion 114 or the inner peripheral portion 113 forms the stamping edge 123. As described above, the remaining thickness of the connecting portion 114 is less than the remaining thickness of the inner peripheral portion 113.

[0115] As a first example, when the connecting portion 114 is long enough, the connecting portion 114 can be unfolded to form not only the second peripheral portion 122b but also the stamping edge 123. The inner peripheral portion 113 can be unfolded to form the second bottom portion 121b. In this case, the thickness of the stamping edge 123 can be the same as the thickness t2 of the second peripheral portion 122b and can be less than the thickness t4 of the second bottom portion 121b. Additionally, the stamping edge 123 can connect the second peripheral portion 122b and the second bottom portion 121b.

[0116] As a second example, when the connecting portion 114 is shorter than the connecting portion 114 in the first example, the connecting portion 114 can be unfolded to form the second peripheral portion 122b, and the inner peripheral portion 113 can be unfolded to form the stamping edge 123 and the second bottom portion 121b. In this case, the thickness of the stamping edge 123 can be the same as the thickness t4 of the second bottom portion 121b and can be greater than the thickness t2 of the second peripheral portion 122b. Additionally, the stamping edge 123 can connect the second peripheral portion 122b and the second bottom portion 121b.

[0117] As a third example, when the connecting portion 114 is shorter than the connecting portion 114 in the second example, the connecting portion 114 can be unfolded to form the second peripheral portion 122b, and the inner peripheral portion 113 can be unfolded to form a third peripheral portion, the stamping edge 123, and the second bottom portion 121b. The third peripheral portion can be the portion between the second peripheral portion 122b and the stamping edge 123. That is, the peripheral portion 122 of the cup portion 120 can further include a third peripheral portion that is connected to the second peripheral portion 122b and has a thickness greater than the thickness of the second peripheral portion 122b.

[0118] In this case, the thickness of the stamping edge 123 can be the same as the thickness t4 of each of the third peripheral portion and the second bottom portion 121b and can be greater than the thickness t2 of the second peripheral portion 122b. Additionally, the stamping edge 123 can connect the third peripheral portion and the second bottom portion 121b.

[0119] When summarizing the first example to the third example, the thickness of the stamping edge 123 can be the same as the thickness t2 of the second peripheral portion 122b or the thickness t4 of the second bottom portion 121b. Additionally, the thickness of the stamping edge 123 can be less than the thickness t4 of the second bottom portion 121b or greater than the thickness t2 of the second peripheral portion 122b.

[0120] The subject matter disclosed above is considered illustrative and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments that fall within the true spirit and scope of the present invention.

[0121] Therefore, the embodiments of the present invention are considered illustrative rather than restrictive, and the technical spirit of the present invention is not limited to the foregoing embodiments.

[0122] Therefore, the scope of the present invention is not defined by the detailed description of the present invention, but by the appended claims, and all differences within the scope will be construed as being included in the present invention.

[0123] [Description of Reference Numerals]

[0124] 10: Mold 12: First opening

[0125] 14: Protrusion 20: Ejector

[0126] 22: Second opening 121 30: Sub-mold

[0127] 40: Punch 50: Sub-punch

[0128] 100: Soft film package 101: Central part

[0129] 110: Recessed part 111: Mold edge

[0130] 112: Outer peripheral part 113: Inner peripheral part

[0131] 114: Connecting part 115: Connecting edge

[0132] 120: Cup part 121: Bottom

[0133] 12la: First bottom 12lb: Second bottom

[0134] 122: Peripheral part 122a: First peripheral part

[0135] 122b: Second peripheral part 130: Platform

Claims

1. A molding device for molding a soft packaging film, the molding device comprises: a mold, in which a first opening is defined; a demolding device, which is arranged above the mold to fix the soft packaging film and has a second opening; a sub-mold, which has a height that can be changed relative to the mold inside the first opening; a punch, which is configured to press the soft packaging film through the second opening and is arranged to face the sub-mold; and a sub-punch, which is configured to press the soft packaging film between the inner periphery of the first opening and the outer periphery of the sub-mold through the space between the inner periphery of the second opening and the outer periphery of the punch.

2. The molding device according to claim 1, wherein, the sub-punch is configured to press the soft packaging film once in a state where the top surface of the sub-mold and the top surface of the mold are arranged on the same plane, and the punch and the sub-punch are configured to press the soft packaging film a second time in a state where the top surface of the sub-mold is arranged below the top surface of the mold.

3. The molding device according to claim 1, wherein, the sub-punch is arranged to surround the outer periphery of the punch.

4. The molding device according to claim 1, wherein, a protrusion is provided on the mold, which protrudes from the inner periphery of the first opening towards the outer periphery of the sub-mold and overlaps with the sub-punch in the vertical direction.

5. A molding method for molding a soft packaging film, the molding method comprises: fixing the soft packaging film between a mold formed with a first opening and a demolding device formed with a second opening; causing the sub-punch to press the soft packaging film once between the outer periphery of a sub-mold arranged in the first opening and the inner periphery of the first opening through the second opening; and causing a punch arranged to face the sub-mold with the soft packaging film interposed therebetween and the sub-punch to press the soft packaging film a second time towards the first opening through the second opening.

6. The molding method according to claim 5, wherein, in the fixing and / or the first pressing, the top surface of the sub-mold and the top surface of the mold are arranged on the same plane.

7. The molding method according to claim 5, wherein, in the fixing and / or the first pressing, the soft packaging film is fixed between the sub-mold and the punch.

8. The molding method according to claim 5, wherein, in the second pressing, the bottom surface of the punch and the bottom surface of the sub-punch are arranged on the same plane.

9. The molding method according to claim 5, wherein, in the first pressing, the sub-punch molds a recessed portion with a first depth in the soft packaging film, and in the second pressing, the punch and the sub-punch mold a cup portion with a second depth deeper than the first depth in the soft packaging film.

10. The molding method according to claim 9, wherein, in the second pressing, the recessed portion expands to be molded into the cup portion.

11. The molding method according to claim 5, wherein, A protruding portion protruding from the inner periphery of the first opening toward the outer periphery of the sub-mold is formed on the mold, and in the secondary pressing, the sub-punch presses the soft package film to a depth at which the soft package film contacts the protruding portion.

12. The molding method according to claim 11, wherein, in the secondary pressing, the top surface of the sub-mold and the top surface of the protruding portion are disposed on the same plane.

13. A soft-pack type battery case, comprising: a cup portion having a concave shape; and a platform disposed at a periphery of the cup portion, wherein a peripheral portion of the cup portion includes: a first peripheral portion connected to the platform through a mold edge; and a second peripheral portion connected to the first peripheral portion and having a thickness smaller than that of the first peripheral portion.

14. The soft-pack type battery case according to claim 13, wherein, a bottom portion of the cup portion includes: a first bottom portion disposed at a center of the bottom of the cup portion; and a second bottom portion having a thickness smaller than that of the first bottom portion and connected to the peripheral portion of the cup portion through a stamping edge.

15. The soft-pack type battery case according to claim 14, wherein, the thickness of the second peripheral portion is smaller than the thickness of the second bottom portion.

16. The soft-pack type battery case according to claim 14, wherein, the thickness of the first peripheral portion is smaller than the thickness of the first bottom portion.

17. The soft-pack type battery case according to claim 14, wherein, the thickness of the stamping edge connecting the second peripheral portion and the second bottom portion is the same as the thickness of the second bottom portion or the second peripheral portion.

18. The soft-pack type battery case according to claim 14, wherein, the thickness of the stamping edge connecting the second peripheral portion and the second bottom portion is the same as the thickness of the second peripheral portion and smaller than the thickness of the second bottom portion.

19. The soft-pack type battery case according to claim 14, wherein, the thickness of the stamping edge connecting the second peripheral portion and the second bottom portion is the same as the thickness of the second bottom portion and larger than the thickness of the second peripheral portion.

20. The soft-pack type battery case according to claim 14, wherein, the peripheral portion of the cup portion further includes a third peripheral portion connected to the second peripheral portion and having a thickness larger than that of the second peripheral portion, and the thickness of the stamping edge connecting the third peripheral portion and the second bottom portion is the same as the thickness of each of the third peripheral portion and the second bottom portion and larger than the thickness of the second peripheral portion.

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