Bag type battery shell and forming equipment thereof

Abstract

A pouch-type battery case according to an embodiment of the present invention may include a pair of cases. At least one of the pair of housings may include: a recessed cup; the platform part is arranged on the periphery of the cup part, and a sealing part is arranged on the platform part; and a protruding portion protruding from the platform portion in a direction opposite to a depth direction of the cup portion. At least a portion of the sealing portion may be disposed on the protrusion.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority of Korean Patent Application No. 10-2022-0101639 filed on August 12, 2022, and Korean Patent Application No. 10-2023-0094872 filed on July 20, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0004] The invention relates to a pouch-type battery casing and a molding device for manufacturing the pouch-type battery casing. Background Art

[0005] Generally, types of secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, lithium-ion polymer batteries, etc. These secondary batteries are suitable not only for small products such as digital cameras, P-DVDs, MP3Ps, mobile phones, PDAs, portable game devices, power tools, and electric bicycles, but also for large products such as electric vehicles or hybrid vehicles that require high output, energy storage systems for storing excess electricity or newly regenerated energy, and backup energy storage systems.

[0006] To manufacture these secondary batteries, the positive electrode collector and the negative electrode collector are coated with electrode active material slurry to manufacture the positive electrode and the negative electrode, and then the positive electrode and the negative electrode are stacked on both sides of the separator to form an electrode assembly having a predetermined shape. Afterwards, the battery case accommodates the electrode assembly and is sealed after injecting the electrolyte.

[0007] According to the material of the shell containing the electrode assembly, the secondary battery is divided into a pouch type, a can type, etc. In the pouch type, the electrode assembly is contained in a bag made of a flexible polymer material. In the can type, the electrode assembly is contained in a shell made of a material such as metal or plastic.

[0008] Reference Figure 1, the pouch-type battery case 1 is generally manufactured by performing a press process on a flexible pouch sheet to form a cup portion 2. When the cup portion 2 is formed, the electrode assembly is accommodated inside the cup portion 2, and the platform portion 4 is sealed to manufacture a secondary battery. Drawing molding of this press process is performed by inserting the pouch sheet into a molding device such as a press device, and applying pressure to the pouch sheet by using a punch to stretch the pouch sheet.

[0009] During the forming operation of the cup portion 3, corrugations 5 may be generated around the cup portion 3 of the bag sheet. In particular, such corrugations 5 may protrude near the corner 3 of the cup portion 2. Therefore, there is a problem that sealing defects of the pouch-type battery case 1 may occur due to the corrugations 5. Summary of the invention

[0010] Technical issues

[0011] To solve the above problems, an object of the present invention is to provide a pouch-type battery case whose sealing quality is improved due to a protrusion provided on the periphery of a cup portion and a molding apparatus for manufacturing the pouch-type battery case.

[0012] Technical Solution

[0013] The pouch-type battery case according to an embodiment of the present invention may include a pair of cases. At least one of the pair of cases may include: a concave cup portion; a platform portion, the platform portion being disposed on the periphery of the cup portion and having a sealing portion disposed on the platform portion; and a protrusion, the protrusion protruding from the platform portion in a direction opposite to the depth direction of the cup portion. At least a portion of the sealing portion may be disposed on the protrusion.

[0014] Each of the pair of housings may include the cup portion, the platform portion, and the protrusion.The protrusion of one housing and the protrusion of the other housing of the pair of housings may contact each other to be sealed.

[0015] The protrusion may extend along the sealing portion.

[0016] At least a portion of the protrusion may be disposed outside a corner of the cup portion.

[0017] The width of the protrusion may be greater than the width of the sealing portion.

[0018] Edges of the sealing portion at both sides in the width direction may be disposed inward from edges of the protruding portion at both sides in the width direction, respectively.

[0019] The protrusion may include a first portion disposed outside the cup portion in a width direction of the cup portion and a second portion connected to the first portion and disposed outside the cup portion in a length direction of the cup portion.

[0020] The first portion may extend parallel to a length of the cup portion, and the second portion may extend parallel to a width of the cup portion.

[0021] According to an embodiment of the present invention, a molding device may include: a mold defining a molding groove; a punch arranged to face the molding groove; a demolding piece arranged on the periphery of the punch to face the mold; a secondary molding groove defined in the demolding piece; a secondary punch protruding from the mold to face the secondary molding groove; a pressing portion arranged in the secondary molding groove; and an elastic member configured to apply an elastic force directed to the secondary punch to the pressing portion.

[0022] The auxiliary punch may be arranged outside the forming groove.

[0023] At least a portion of the auxiliary punch may be disposed outside a corner of the forming groove.

[0024] The auxiliary punch may include: a first punch portion disposed outside the molding groove in a width direction of the molding groove; and a second punch portion connected to the first punch portion and disposed outside the molding groove in a length direction of the molding groove.

[0025] The first punch portion may extend parallel to a length of the forming groove, and the second punch portion may extend parallel to a width of the cup portion.

[0026] The auxiliary punch may further include: a third punch portion disposed outward from the first punch portion and spaced apart from the first punch portion by a predetermined gap; and a fourth punch portion connecting the third punch portion to the first punch portion.

[0027] The third punch portion may extend in parallel with the first punch portion, and the fourth punch portion may extend in parallel with the second punch portion.

[0028] A mounting groove may be defined in the die, and the auxiliary punch is mounted in the mounting groove.

[0029] Beneficial Effects

[0030] According to the preferred embodiment of the present invention, due to the protrusion, it is possible to prevent ripples from being generated in the bag sheet around the cup portion.

[0031] Furthermore, when compared with a battery case in which corrugations are generated around a cup portion in a platform portion according to the related art, a protrusion protruding in a direction opposite to the cup portion may be sealed to improve the sealing reliability of the battery case and minimize the problem that electrolyte may leak.

[0032] The effects of the present invention are not limited to the above-mentioned, and more various effects are included in the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is an enlarged view illustrating the periphery of a corner portion of a cup portion of a pouch-type battery case according to the related art.

[0034] Figure 2 is a schematic cross-sectional view of a molding apparatus according to a first embodiment of the present invention.

[0035] Figure 3 is a plan view of a mold included in the molding apparatus according to the first embodiment of the present invention.

[0036] Figure 4 is a schematic diagram of a pouch-type battery case molded by a molding apparatus according to a first embodiment of the present invention.

[0037] Figure 5 is along Figure 4 A cross-sectional view taken along line AA' in FIG.

[0038] Figure 6 It is a graphic Figure 4 0 is a side view of a state in which the pouch-type battery case shown in FIG. 1 is sealed.

[0039] Figure 7 yes Figure 4 A modified example of the pouch-type battery case shown in .

[0040] Figure 8 It is a graphic Figure 7 FIG. 4 is a side view of a state in which a pouch-type battery case is folded.

[0041] Fig. 9 is a plan view of a mold included in a molding apparatus according to a second embodiment of the present invention.

[0042] Fig.10 is a schematic diagram of a pouch-type battery case molded by a molding apparatus according to a second embodiment of the present invention.

[0043] Fig.11 It is a graphic Fig.10 1 is a plan view of a state in which a pouch-type battery case is sealed.

[0044] Fig.12is a plan view of a mold included in a molding apparatus according to a third embodiment of the present invention.

[0045] Fig.13 is a schematic diagram of a pouch-type battery case molded by a molding apparatus according to a third embodiment of the present invention.

[0046] Fig.14 It is a graphic Fig.13 1 is a plan view of a state in which a pouch-type battery case is sealed. DETAILED DESCRIPTION

[0047] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. However, the present invention can be implemented in different forms and is not limited to the embodiments described below.

[0048] In order to clearly describe the present invention, parts irrelevant to the description, or detailed description of related well-known technologies that may unnecessarily obscure the gist of the present invention will be excluded. Throughout the application, the same reference numerals denote the same elements.

[0049] Furthermore, the terms or words used in the specification and claims should not be restrictively interpreted as ordinary meanings or dictionary-based meanings, but should be interpreted as meanings and concepts consistent with the scope of the present invention based on the principle that the inventor can appropriately define the concepts of the terms to best describe and interpret his or her invention.

[0050] Figure 2 is a schematic cross-sectional view of a molding apparatus according to a first embodiment of the present invention. Figure 3 is a plan view of a mold included in the molding apparatus according to the first embodiment of the present invention.

[0051] The molding apparatus according to the first embodiment of the present invention may mold a pouch sheet (not shown) to manufacture a pouch-type battery case 100 (see Figure 3 ). The bag sheet may be a sheet member laminated with a plurality of layers. For example, the bag sheet may include: a first resin layer (e.g., a polypropylene material) constituting one surface, a second resin layer (e.g., a polyethylene terephthalate material) constituting the other surface, and a metal layer (e.g., an aluminum material) disposed between the first resin layer and the second resin layer. The bag sheet may have flexibility and formability. The bag sheet may be referred to as a bag film.

[0052] The molding equipment may include: a mold 10 defining a molding groove 11, a punch 20 arranged to face the molding groove 11, a demolding piece 30 arranged on the periphery of the punch 20 to face the mold 10, a secondary molding groove 40 defined in the demolding piece 30, and a secondary punch 50 protruding from the mold 10 to face the secondary molding groove 40.

[0053] The mold 10 may have a substantially horizontal plate shape. When the bag sheet is disposed between the mold 10 and the demolding member 30, the top surface of the mold 10 may face the bottom surface of the bag sheet.

[0054] The mold 10 may be bonded to a mold back plate 10a.

[0055] At least one molding groove 11 recessed downward from the top surface of the mold 10 may be defined in the mold 10. The molding groove 11 may penetrate to the bottom surface of the mold 10, but is not limited thereto. A punch 20 described later may be inserted into the molding groove 11 and press the bag sheet so that a cup portion 110 (see FIG. 1 ) is formed in the bag sheet. Figure 4 ).

[0056] According to this embodiment, a pair of molding grooves 11 separated from each other may be defined in the mold 10. The pair of molding grooves 11 may be disposed adjacent to each other, and the mold 10 may have a partition wall 12 disposed between the pair of molding grooves 11. When stretch molding is performed on the bag sheet by simultaneously inserting a punch 20 described later into each of the pair of molding grooves 11, a pair of cup portions 110 may be disposed corresponding to the pair of molding grooves 11, and a bridge portion 130 corresponding to the partition wall 12 of the mold 10 may be disposed between the pair of cup portions 110.

[0057] The demolding member 30 may have a substantially horizontal plate shape. When the bag sheet is disposed between the mold 10 and the demolding member 30, the bottom surface of the demolding member 30 may face the top surface of the bag sheet. The demolding member 30 may fix the bag sheet together with the mold 10.

[0058] An open portion vertically penetrated and provided with the punch 20 may be defined in the stripper 30. That is, the stripper 30 may surround the punch 20.

[0059] The stripper 30 may be coupled to the lower side of the stripper back plate 30a. A sub-opening portion corresponding to the opening portion of the stripper 30 may be defined in the stripper back plate 30a. Therefore, the punch 20 may protrude upward from the stripper back plate 30a.

[0060] At least one of the demolding member 30 or the mold 10 may be configured to be liftable so that the distance between the demolding member 30 and the mold 10 changes. In a state where the demolding member 30 and the mold 10 are spaced apart from each other, a bag sheet may be introduced between the demolding member 30 and the mold 10. In a state where the bag sheet is disposed between the demolding member 30 and the mold 10, the demolding member 30 may be lowered toward the mold 10, or the mold 10 may be raised toward the demolding member 30. Therefore, the bag sheet may be fixed between the top surface of the mold 10 and the bottom surface of the demolding member 30.

[0061] The punch 20 may be disposed in an open portion of the demolding member 30. When the bag sheet is disposed between the mold 10 and the demolding member 30, the punch 20 may face the molding groove 11 defined in the mold 10 with the bag sheet therebetween. When a pair of molding grooves 11 is defined in the mold 10, the punch 20 may also be disposed in pairs to correspond to the pair of molding grooves 11. The pair of punches 20 may be connected to each other, or may be separated from each other.

[0062] When the mold 10 and the demolding member 30 are raised relative to the punch 20 while the bag sheet is fixed, the punch 20 can be inserted into the molding groove 11 of the mold 10 while pressing the bag sheet. Alternatively, when the punch 20 is lowered relative to the mold 10 and the demolding member 30 while the mold 10 and the demolding member 30 are fixing the bag sheet, the punch 20 can be inserted into the molding groove 11 of the mold 10 while pressing the bag sheet.

[0063] Therefore, the portion of the bag sheet pressed by the punch 20 and the portion around it can be stretched, and the cup portion 110 can be formed (see FIG. Figure 4 ).

[0064] The secondary molding groove 40 may be formed in the demolding member 30. In more detail, the secondary molding groove 40 may be recessed upward from the bottom surface of the demolding member 30. The secondary molding groove 40 may be provided to have a predetermined depth, or pass through the demolding member 30.

[0065] The secondary molding groove 40 may be arranged outward from the punch 20. That is, the secondary molding groove 40 may be provided outward from the opening portion defined in the demolding member 30. The secondary punch 50 described later may be inserted into the secondary molding groove 40 and press the bag sheet so that the protrusion 140 is provided on the bag sheet (see Figure 4 ).

[0066] The auxiliary punch 50 may protrude upward from the die 10 . The auxiliary punch 50 may face the auxiliary molding groove 40 defined in the demolding member 30 .

[0067] The auxiliary punch 50 may be installed in the die 10. For example, a mounting groove 13 in which the auxiliary punch 50 is installed may be defined in the die 10. However, the embodiments of the present invention are not limited thereto, and the auxiliary punch 50 and the die 10 may be provided as one body.

[0068] The auxiliary punch 50 may be disposed outward from the forming groove 11 .

[0069] Reference Figure 3 , the auxiliary punch 50 of the molding apparatus according to this embodiment may be disposed outside the corners of the molding groove 11. Each molding groove 11 may have a substantially rectangular shape, and the portion corresponding to the vertex of the rectangular shape may be referred to as the corner of the molding groove 11. It may also be easily understood by those skilled in the art that the corners of the molding groove 11 are set to be rounded.

[0070] A plurality of auxiliary punches 50 may be provided. Figure 3 As shown in , the plurality of auxiliary punches 50 may include a first auxiliary punch 50A disposed outside a corner of one molding groove 11 , and a second auxiliary punch 50B disposed outside a corner of another molding groove 11 .

[0071] Likewise, a plurality of auxiliary molding grooves 40 may be provided. The first auxiliary punch 50A may be inserted into one of the plurality of auxiliary molding grooves 40, and the second auxiliary punch 50B may be inserted into another one.

[0072] A plurality of auxiliary punches 50 may be provided on a side opposite to the partition wall 12 of the die 10. In more detail, a pair of inner corners among the four corners of each molding groove 11 may be defined by the partition wall 12, and a pair of outer corners may be provided on a side opposite to the partition wall 12. Each auxiliary punch 50 may be provided outside the outer corner of the molding groove 11. In more detail, the first auxiliary punch 50A may be provided outside the outer corner of one molding groove 11, and the second auxiliary punch 50B may be provided outside the outer corner of another molding groove 11. That is, the first auxiliary punch 50A and the second auxiliary punch 50B may each be provided in pairs.

[0073] Each of the auxiliary punches 50 may have a shape surrounding a corner of the forming groove 11. In more detail, each of the auxiliary punches 50 may include a first punch portion 51 and a second punch portion 52.

[0074] The first punch portion 51 may be disposed outward from the molding groove 11 in a width direction of the molding groove 11. The first punch portion 51 may extend in parallel with the length of the molding groove 11.

[0075] The second punch portion 52 may be disposed outward from the forming groove 11 in the length direction of the forming groove 11. The second punch portion 52 may extend parallel to the width of the forming groove 11.

[0076] The first punch portion 51 and the second punch portion 52 may be connected to each other.

[0077] The distance between the molding groove 11 and the auxiliary punch 50 may be substantially constant on the top surface of the mold 10. In more detail, the distance between the first punch portion 51 and the molding groove 11 in the width direction of the molding groove 11 may correspond to the distance between the second punch portion 52 and the molding groove 11 in the length direction of the molding groove 11. However, embodiments of the present invention are not limited thereto.

[0078] The secondary molding groove 40 may have a shape corresponding to that of the secondary punch 50. When the secondary punch 50 is inserted into the secondary molding groove 40, a predetermined gap may be defined between the inner circumference of the secondary molding groove 40 and the outer circumference of the secondary punch 50 so that the bag sheet is easily stretched.

[0079] Therefore, the portion of the bag sheet pressed by the auxiliary punch 50 inserted into the auxiliary molding groove 40 and the portion around it can be stretched, and the protrusion 140 (see Figure 4 Due to the protrusion 140, it is possible to prevent ripples from being generated in the bag sheet around the corners of the cup portion 110.

[0080] The molding apparatus may further include a pressing portion 61 disposed inside the secondary molding groove 40 , and an elastic member 62 applying elastic force to the pressing portion 61 .

[0081] The pressing portion 61 may have a shape corresponding to the auxiliary molding groove 40 and the auxiliary punch 50. The pressing portion 61 may be slidably provided in the auxiliary molding groove 40.

[0082] The elastic member 62 may be disposed inside the auxiliary molding groove 40. The elastic member 62 may apply elastic force to the pressing portion 61 toward the auxiliary punch 50. For example, the elastic member 62 may be a spring.

[0083] Therefore, the pressing part 61 can apply a predetermined surface pressure to the bag sheet stretched into the secondary molding groove 40 through the secondary punch 50. Therefore, a uniform surface pressure can be applied to the bag sheet stretched into the secondary molding groove 40, and generation of corrugations in the bag sheet can be prevented.

[0084] Figure 4 is a schematic diagram of a pouch-type battery case molded by the molding apparatus according to the first embodiment of the present invention. Figure 5 is along Figure 4 A cross-sectional view taken along line AA' in FIG. Figure 6 It is a graphic Figure 4 0 is a side view of a state in which the pouch-type battery case shown in FIG. 1 is sealed.

[0085] Hereinafter, a pouch type battery case 100 manufactured by the molding apparatus according to the first embodiment will be described as an embodiment of the present invention.

[0086] The pouch-type battery case 100 (hereinafter referred to as "battery case") can accommodate an electrode assembly (not shown) therein and can be provided by molding a pouch sheet. In more detail, when the pouch sheet is subjected to deep drawing molding by the molding apparatus according to an embodiment of the present invention, a portion of the pouch sheet can be stretched to provide the cup portion 110 and the protrusion 140, thereby manufacturing the battery case 100.

[0087] The battery case 100 may include a recessed cup portion 110 , a platform portion 120 disposed on the periphery of the cup portion 110 , and a protrusion 140 protruding from the platform portion 120 in a direction opposite to a depth direction of the cup portion 110 and disposed outside the cup portion 110 .

[0088] In more detail, the battery case 100 may include a pair of cases 101 and 102 , in more detail, a first case 101 and a second case 102 , and at least one of the first case 101 or the second case 102 may include a cup portion 110 , a platform portion 120 , and a protrusion 140 .

[0089] In the following, Figure 4 As shown in FIG. 1 , a case where one side of the first housing 101 and one side of the second housing 102 are connected to each other will be described as an example. However, the embodiments of the present invention are not limited thereto, and the first housing 101 and the second housing 102 may also be separated from each other and manufactured separately.

[0090] In this embodiment, each of the first housing 101 and the second housing 102 may include a cup portion 110 , a platform portion 120 , and a protrusion 140 .

[0091] That is, the battery case 100 may include a pair of cup portions 110. The battery case 100 may further include a bridge portion 130 disposed between the pair of cup portions 110.

[0092] The cup portion 110 may be recessed from the platform portion 120 to a predetermined depth to define a space for accommodating an electrode assembly (not shown). The electrode assembly may be accommodated in one of the cup portions 110, and then the bridge portion 130 may be folded so that the pair of cup portions 110 face each other. Then, the other cup portion 110 may cover the electrode assembly from the upper side. Therefore, the electrode assembly may be accommodated inside the pair of cup portions 110.

[0093] Each cup portion 110 may have a substantially rectangular shape. The portion where the long side and the short side of each cup portion 110 meet each other may be referred to as a corner 111 of the cup portion 110. It may also be easily understood by those skilled in the art that the corner 111 of the cup portion 110 is configured to be rounded.

[0094] The platform portion 120 of the first housing 101 and the platform portion 120 of the second housing 102 may be connected to each other at both sides of the bridge portion 130. When the bridge portion 130 is folded, the platform portions 120 may be folded together. In more detail, the portion where the platform portion 120 of the first housing 101 and the platform portion 120 of the second housing 102 are connected to each other may be folded together with the bridge portion 130.

[0095] The protrusion 140 may protrude from the platform portion 120 in a direction opposite to the cup portion 110. For example, the cup portion 110 may be recessed downward, and the protrusion 140 may protrude upward.

[0096] The protrusion 140 may be disposed outward from the cup portion 110. At least a portion of the protrusion 140 may be disposed outside a corner of the cup portion 110.

[0097] In this embodiment, the protrusion 140 may be disposed on the platform portion 120 and outside the corner portion of the cup portion 110 .

[0098] A plurality of protrusions 140 may be provided. The plurality of protrusions 140 may include a first protrusion 140A provided outside a corner of the cup portion 110 and a second protrusion 140B provided outside a corner of another cup portion 110. That is, the first housing 101 may include one of the first protrusion 140A and the second protrusion 140B, and the second housing 102 may include the other.

[0099] Each protrusion 140 may have a shape surrounding a corner of the cup portion 110. In more detail, each protrusion 140 may include a first portion 141 and a second portion 142.

[0100] The first portion 141 may be disposed outward from the cup portion 110 in a width direction of the cup portion 110. The first portion 141 may extend parallel to the length of the cup portion 110.

[0101] The second portion 142 may be disposed outward from the cup portion 110 in the length direction of the cup portion 110. The second portion 142 may extend parallel to the width of the cup portion 110.

[0102] The first portion 141 and the second portion 142 may be connected to each other.

[0103] The distance between the cup portion 110 and the protrusion 140 may be substantially constant on the platform portion 120. In more detail, the distance between the first portion 141 and the cup portion 110 in the width direction of the cup portion 110 may correspond to the distance between the second portion 142 and the cup portion 110 in the length direction of the cup portion 110. However, embodiments of the present invention are not limited thereto.

[0104] A plurality of protrusions 140 may be provided on a side opposite to the bridge portion 130. In more detail, a pair of inner corners among the four corners of each cup portion 110 may be defined by the bridge portion 130, and a pair of outer corners may be provided on a side opposite to the bridge portion 130. Each protrusion 140 may be provided outside the outer corners of the cup portion 110. In more detail, a first protrusion 140A may be provided outside the outer corner of one cup portion 110, and a second protrusion 140B may be provided outside the outer corner of another cup portion 110. That is, the first protrusion 140A and the second protrusion 140B may each be provided in pairs.

[0105] Although not shown in the drawings, the pair of first protrusions 140A may be provided to be connected to each other. In more detail, the corresponding first portions 141 of the pair of first protrusions 140A may be elongated so as to be connected to each other.

[0106] In the protrusion 140 and the cup portion 110 , the bag sheets may be stretched in opposite directions, and thus it is possible to prevent ripples from being generated in the platform portion 120 around the corners of the cup portion 110 .

[0107] When the bridging portion 130 is folded, the platform portion 120 of the first shell 101 and the platform portion 120 of the second shell 102 may face each other and may be sealed with each other. The area where the platform portion 120 of the first shell 101 and the platform portion 120 of the second shell 102 are sealed with each other may be defined as a sealing portion 150. The sealing portion 150 may extend along the periphery of the cup portion 110. When the first shell 101 and the second shell 102 are connected by the bridging portion 130 as in this embodiment, the sealing portion 150 may be arranged along three sides of the battery housing 10. On the contrary, when the first shell 101 and the second shell 102 are separated from each other, the sealing portion 150 may be arranged along four sides of the battery housing 100.

[0108] At least a portion of the sealing portion 150 may be disposed on the protrusion 140 .

[0109] That is, the protrusion 140 may be sealed. When each of a pair of housings 101 and 102 includes a protrusion 140 as in this embodiment, a protrusion 140A of one of the pair of housings 101 and 102 and a protrusion 140B of the other may contact each other to be sealed. That is, the protrusion 140A and the protrusion 140B may contact each other to be sealed. In more detail, the sealing portion 150 of the battery housing 100 may be provided as a portion that passes through the protrusion 140A and contacts the protrusion 140B.

[0110] The width W1 of the protrusion 140 may be greater than the width W2 of the sealing portion 150. In more detail, the edges of the sealing portion 150 at both sides in the width direction may be respectively disposed inward from the edges of the protrusion 140 at both sides in the width direction. That is, the sealing tool for sealing the battery case 100 may press and seal the inside of the protrusion 140 without pressing both sides of the protrusion 140 in the width direction. Therefore, a high sealing quality can be maintained.

[0111] The sealing tool (not shown) for sealing the battery case 100 can set the sealing portion 150 by pressing the protrusion 140 together with the portion of the platform portion 120 on which the protrusion 140 is not set (in this embodiment, the portion of the periphery of the cup portion except for the periphery of the corner portion of the cup portion). The protrusion 140 can protrude from the platform portion 120 to have a height that does not interfere with the setting of the sealing portion 150. Therefore, when the first protrusion 140A and the second protrusion 140B contact each other, the platform portion 120 of the first case 101 and the platform portion 120 of the second case 102 can also contact or be adjacent to each other, and the sealing portion 150 can be easily set.

[0112] Since the protrusion 140 is sealed as above, when compared with a battery case according to the related art in which corrugations are generated around the cup portion in the platform portion, the sealing reliability of the battery case 100 may be improved, and a problem that the electrolyte may leak may be minimized.

[0113] In particular, when the protrusion 140 is provided only around the corner 111 of the cup portion 110 as in this embodiment, it is advantageous in that the stretching amount of the bag sheet stretched into the molding groove 11 of the mold 10 during the molding process of the cup portion 110 can be made uniform. In addition, since the ripples are concentrated around the corners of the cup portion 110 when the protrusion 140 is not present on the platform portion 120, the ripples can be effectively removed.

[0114] In addition, since the bridge portion 130 is folded, it is not necessary to seal the bridge portion 130 separately. When the protrusion 140 is provided on the side of the inner corner portion 111 of the cup portion 110 adjacent to the bridge portion 130, the thickness of the bridge portion 130 can be increased, so there is a problem that the energy density and appearance quality of the battery case 100 can be reduced. That is, since a plurality of protrusions 140 are provided on the side opposite to the bridge portion 130, the energy density and appearance quality of the battery case 100 can be maintained high, and the sealing reliability can also be improved.

[0115] Figure 7 yes Figure 4 A modified example of the pouch-type battery case shown in . Figure 8 It is a graphic Figure 7 FIG. 4 is a side view of a state in which a pouch-type battery case is folded.

[0116] Hereinafter, the contents common to the above contents will be omitted, and the description will focus on the differences.

[0117] In the pouch type battery case, only one of the first case 101 and the second case 102 may include the cup portion 110, the platform portion 120, and the protrusion 140. That is, the battery case 100 may include a single cup portion 110.

[0118] A plurality of protrusions 140 may be respectively disposed on the four corners 111 of the cup portion 110. That is, the first housing 101 or the second housing 102 may include four protrusions 140. Although not shown in the drawings, at least some of the four protrusions 140 may be disposed to be connected to each other. In more detail, the corresponding first portions 141 and / or second portions 142 of at least some of the four protrusions 140 may be elongated so as to be connected to each other.

[0119] When the first housing 101 and the second housing 102 are connected to each other, the first housing 101 and the second housing 102 may be separated by the folding line 130 ′. Hereinafter, a case where the second housing 102 includes the cup portion 110 , the platform portion 120 , and the protrusion 140 will be described as an example.

[0120] The electrode assembly (not shown) may be accommodated in the cup portion 110 provided in the second case 102 , and then the folding line 130 ′ may be folded such that the first case 101 covers the cup portion 110 .

[0121] When the folding line 130 ′ is folded, the second housing 102 and the platform portion 120 of the first housing 101 may face each other and may be sealed with each other. An area where the second housing 102 and the platform portion 120 of the first housing 101 are sealed with each other may be defined as a sealing portion 150 .

[0122] The protrusion 140 of the second housing 102 may contact the first housing 101 to be sealed. In more detail, the sealing portion 150 may be provided through a portion where the protrusion 140 of the second housing 102 and the first housing 101 contact each other.

[0123] When the folding line 130' is folded, it is not necessary to seal the folding line 130' separately. Therefore, in order to arrange the folding line 130' adjacent to the cup portion 110 as much as possible, an embodiment in which the protrusion 140 is arranged at a side opposite to the folding line 130' may also be provided.

[0124] That is to say, different from Figure 7 As shown in , the first shell 101 or the second shell 102 may include a pair of protrusions 140 respectively disposed on one side of the outer corner of the cup portion 110, and may not include a pair of protrusions respectively disposed on one side of the inner corner of the cup portion 110.

[0125] Fig. 9 is a plan view of a mold included in a molding apparatus according to a second embodiment of the present invention.

[0126] The auxiliary punch 50 protruding from the die 10 of the molding apparatus according to this embodiment may be disposed outside the molding groove 11. In more detail, the auxiliary punch 50 may extend along the circumference of the molding groove 11.

[0127] At least a portion of the auxiliary punch 50 may be disposed outside a corner portion of the forming groove 11 .

[0128] The auxiliary punch 50 may include a first punch portion 51 extending in parallel with the length of the forming groove 11 , and a second punch portion 52 extending in parallel with the width of the forming groove 11 .

[0129] The auxiliary punch 50 may form a single closed loop surrounding the pair of molding grooves 11. In more detail, the first punch portion 51 and the second punch portion 52 may form a single closed loop.

[0130] When a single molding groove 11 is provided in the die 10 , the sub-punch 50 may form a single closed loop surrounding the single molding groove 11 .

[0131] However, the embodiments of the present invention are not limited thereto, and the auxiliary punch 50 may also be configured such that the auxiliary punch 50 extends along a closed loop, and some sections are disconnected.

[0132] It may also be easily understood by those skilled in the art that a secondary molding groove 40 corresponding to the secondary punch 50 is defined in the demolding member 30 of the molding apparatus according to this embodiment.

[0133] Fig.10 is a schematic diagram of a pouch-type battery case molded by a molding apparatus according to a second embodiment of the present invention. Fig.11 It is a graphic Fig.10 1 is a plan view of a state in which a pouch-type battery case is sealed.

[0134] Hereinafter, a pouch type battery case 100 manufactured by a molding apparatus according to a second embodiment as an embodiment of the present invention will be described by applying common contents to the above-described contents and focusing on differences.

[0135] The protrusion 140 may be formed by the auxiliary punch 50 of the die 10. The protrusion 140 may have a shape corresponding to the auxiliary punch 50 of the die 10.

[0136] The protrusion 140 may be provided outward from the cup portion 110. The protrusion 140 may extend along the sealing portion 150. That is, the protrusion 140 may be provided on a region of the platform portion 120 to be sealed.

[0137] The protrusion 140 may have a shape surrounding the cup portion 110. In more detail, the protrusion 140 may include a first portion 141 extending in parallel with the length of the cup portion 110, and a second portion 142 extending in parallel with the width of the cup portion 110.

[0138] In a state where the pouch-type battery case 100 is unfolded, the protrusion 140 may form a single closed loop around the pair of cup portions 110. When a single cup portion 110 is provided in the mold 10, the auxiliary punch 50 may form a single closed loop around the single cup portion 110. However, the embodiments of the present invention are not limited thereto, and the protrusion 140 may also be provided such that the protrusion 140 extends along a closed loop, and some sections are disconnected.

[0139] A portion of the protrusion 140 may be disposed outside one cup portion 110, and another portion may be disposed outside the other cup portion 110. That is, a portion of the protrusion 140 may be included in the first housing 101, and another portion may be included in the second housing 102. The protrusion 140 included in the first housing 101 and the protrusion 140 included in the second housing 102 may have symmetrical shapes.

[0140] like Fig.11 As shown in , when the bridge portion 130 is folded, the protrusion 140 of the first shell 101 and the protrusion 140 of the second shell 102 may face each other, and may be sealed with each other to set a sealing portion 150. The sealing portion 150 may extend along the periphery of the cup portion 110. When the first shell 101 and the second shell 102 are connected by the bridge portion 130 as in this embodiment, the sealing portion 150 may be provided along three sides of the battery case 100. On the contrary, when the first shell 101 and the second shell 102 are separated from each other, the sealing portion 150 may be provided along four sides of the battery case 100.

[0141] At least a portion of the sealing portion 150 may be disposed on the protrusion 140. In this embodiment, the sealing portion 150 may be disposed on the protrusion 140. A sealing tool (not shown) for sealing the battery case 100 may press the protrusion 140 to dispose the sealing portion 150.

[0142] In more detail, the sealing part 150 may include a first sealing part 151 disposed along the second portion 142 and a second sealing part 152 disposed along the first portion 141. The first sealing part 151 may be disposed on the second portion 142, and the second sealing part 141 may be disposed on the first portion 141.

[0143] Since the protrusion 140 is sealed as above, when compared with a related art battery case in which corrugations are generated around the corners of the cup portion, the sealing reliability of the battery case 100 may be improved, and a problem that the electrolyte may leak may be minimized.

[0144] In particular, when the protrusion 140 extends along the sealing portion 150 as in this embodiment, there is an advantage in that the sealing reliability of the entire sealing portion 150 can be further improved.

[0145] Fig.12 is a plan view of a mold included in a molding apparatus according to a third embodiment of the present invention.

[0146] The sub-punch 50 protruding from the die 10 of the molding apparatus according to this embodiment may further include a third punch portion 53 disposed outward from the first punch portion 51 , and a fourth punch portion 54 connecting the third punch portion 53 to the first punch portion 51 .

[0147] The third punch portion 53 may be spaced apart by a predetermined gap from the first punch portion 51. In the pouch type battery case 100, a portion corresponding to the gap may serve as an air pocket portion.

[0148] The third punch portion 53 may extend parallel to the first punch portion 51. That is, the third punch portion 53 may be parallel to the length of the molding groove 11.

[0149] The fourth punch portion 54 may extend from the second punch portion 52. That is, the fourth punch portion 54 may also be disposed in line with the second punch portion 52.

[0150] The first punch portion 51 and the second punch portion 52 may form a closed loop surrounding the molding groove 11. The first punch portion 51, the third punch portion 53, and the fourth punch portion 54 may form another closed loop.

[0151] It may also be easily understood by those skilled in the art that a secondary molding groove 40 corresponding to the secondary punch 50 is defined in the demolding member 30 of the molding apparatus according to this embodiment.

[0152] Fig.13 is a schematic diagram of a pouch-type battery case molded by a molding apparatus according to a third embodiment of the present invention. Fig.14 It is a graphic Fig.13 1 is a plan view of a state in which a pouch-type battery case is sealed.

[0153] Hereinafter, a pouch type battery case 100 manufactured by a molding apparatus according to a third embodiment as an embodiment of the present invention will be described by applying common contents to the above-described contents and focusing on differences.

[0154] The protrusion 140 may be formed by the auxiliary punch 50 of the die 10. The protrusion 140 may have a shape corresponding to the auxiliary punch 50 of the die 10.

[0155] The protrusion 140 may be provided outward from the cup portion 110. The protrusion 140 may extend along the sealing portion 150. That is, the protrusion 140 may be provided on a region of the platform portion 120 to be sealed.

[0156] The protrusion 140 may have a shape surrounding the cup portion 110. In more detail, the protrusion 140 may include a first portion 141 extending in parallel with the length of the cup portion 110, and a second portion 142 extending in parallel with the width of the cup portion 110. The protrusion 140 may further include a third portion 143 parallel to the first portion 141, and a fourth portion 144 connecting the first portion 141 to the third portion 143.

[0157] The first portion 141 may be spaced apart from the third portion 143 by a predetermined gap. The fourth portion 144 may extend from the second portion 142 .

[0158] In a state where the pouch type battery case 100 is unfolded, the first portion 141 and the second portion 142 may form one closed loop around the cup portion 110 , and the first portion 141 , the third portion 143 , and the fourth portion 144 may form another closed loop.

[0159] like Fig.14 As shown in FIG. 1 , when the bridge portion 130 is folded, the protrusion 140 of the first housing 101 and the protrusion 140 of the second housing 102 may face each other and may be sealed with each other to provide a sealing portion 150 .

[0160] In this embodiment, the sealing portion 150 may be provided on the protrusion 140. A sealing tool (not shown) for sealing the battery case 100 may press the protrusion 140 to provide the sealing portion 150.

[0161] In more detail, the sealing portion 150 may include a first sealing portion 151 disposed along the second portion 142 and the fourth portion 144, a second sealing portion 152 disposed along the first portion 141, and a third sealing portion 153 disposed along the third portion 143. The first sealing portion 151 may be disposed on the second portion 142 and the fourth portion 144, the second sealing portion 152 may be disposed on the first portion 141, and the third sealing portion 153 may be disposed on the third portion 143.

[0162] Hereinafter, each sealing portion will be briefly described.

[0163] In a state where the bridge portion 130 is folded, the first sealing portion 151 may be provided first. In this case, the first housing 101 and the second housing 102 may have a bag shape with one end open. The electrolyte may be injected into the cup portion 110 through the open end.

[0164] Then, the open end may be sealed to provide the third sealing portion 153. A portion between the cup portion 110 and the third sealing portion 153 may be defined as an air pocket portion 160. Gas generated due to activation of the electrode assembly in the pouch type battery case 100 may be collected in the air pocket portion 160. In addition, a degassing process of punching the air pocket portion 160 to discharge gas may be performed.

[0165] After that, the second sealing portion 152 may be provided. The second sealing portion 152 may be provided adjacent to the cup portion 110. The platform portion 120 may be cut along a cutting line CL provided outward from the second sealing portion 152. That is, a portion provided outside the cutting line CL may be removed. When all of the sealing portions 150 involved in the manufacturing process are provided on the protrusion 140 as described above, the sealing reliability of the entire sealing portion 150 may be further improved.

[0166] The description of the present invention is intended to be illustrative and various changes and modifications may be made by one skilled in the art to which the present invention pertains without departing from the spirit and scope of the present invention as defined in the following claims.

[0167] Therefore, the embodiments described herein are used to describe the technical spirit of the present invention rather than to limit the scope of the technical spirit of the present invention. The scope of the technical spirit of the present invention is not limited to these embodiments.

[0168] Furthermore, the protection scope of the present invention should be determined by reasonable interpretation of the appended claims, and all technical concepts falling within the equivalent scope of the present application should be interpreted as being within the scope of the rights of the present application.

[0169] [Description of symbols]

[0170] 10: Mold 11: Molding groove

[0171] 13: Mounting slot 20: Punch

[0172] 30: demoulding part 40: auxiliary molding groove

[0173] 50: auxiliary punch 61: pressing part

[0174] 62: Elastic member 100: Pouch type battery case

[0175] 110: cup part 111: corner part (of the cup part)

[0176] 120: platform part 130: bridge part

[0177] 140: protrusion 141: first part

[0178] 142: Part 2 143: Part 3

[0179] 144: Part 4 150: Sealing part

[0180] 160: Airbag department.

Claims

1. A pouch-type battery case comprising a pair of cases, wherein at least one of the pair of cases comprises: Concave cup; a platform portion, the platform portion being arranged on the periphery of the cup portion and having a sealing portion arranged on the platform portion; as well as a protrusion protruding from the platform portion in a direction opposite to a depth direction of the cup portion, At least a portion of the sealing portion is disposed on the protruding portion.

2. The pouch-type battery case according to claim 1, wherein each of the pair of cases comprises the cup portion, the platform portion and the protrusion, The protrusion of one housing and the protrusion of the other housing of the pair of housings contact each other to be sealed. The pouch type battery case according to claim 1 , wherein the protrusion extends along the sealing portion. The pouch type battery case according to claim 1 , wherein at least a portion of the protrusion is disposed outside a corner of the cup portion. The pouch type battery case of claim 1 , wherein a width of the protrusion is greater than a width of the sealing portion. 6 . The pouch type battery case according to claim 5 , wherein edges at both sides of the sealing portion in the width direction are respectively disposed inward from edges at both sides of the protruding portion in the width direction.

7. The pouch-type battery case according to claim 1, wherein the protrusion comprises: a first portion, the first portion being arranged outside the cup portion in a width direction of the cup portion; and A second portion is connected to the first portion and is disposed outside the cup portion in a length direction of the cup portion.

8. The pouch-type battery case according to claim 7, wherein the first portion extends parallel to the length of the cup portion, and The second portion extends parallel to a width of the cup portion.

9. A molding device comprising: A mold having a forming groove is defined; A punch configured to face the forming groove; a stripper disposed on a periphery of the punch to face the die; a secondary molding groove defined in the stripper; a secondary punch protruding from the die to face the secondary forming groove; a pressing portion disposed in the secondary molding groove; as well as An elastic member configured to apply an elastic force directed toward the sub-punch to the pressing portion. 10 . The molding apparatus according to claim 9 , wherein the auxiliary punch is disposed outside the molding groove. 11 . The molding apparatus according to claim 10 , wherein at least a portion of the auxiliary punch is disposed outside a corner portion of the molding groove.

12. The molding apparatus according to claim 9, wherein the auxiliary punch comprises: a first punch portion, the first punch portion being arranged outside the molding groove in a width direction of the molding groove; and A second punch portion is connected to the first punch portion and is disposed outside the molding groove in a length direction of the molding groove.

13. The molding apparatus according to claim 12, wherein the first punch portion extends parallel to the length of the molding slot, and The second punch portion extends parallel to a width of the cup portion.

14. The molding apparatus according to claim 12, wherein the auxiliary punch further comprises: a third punch portion, the third punch portion being disposed outward from the first punch portion and being separated from the first punch portion by a predetermined gap; and A fourth punch portion connecting the third punch portion to the first punch portion.

15. The molding apparatus according to claim 14, wherein the third punch portion extends parallel to the first punch portion, and The fourth punch portion extends parallel to the second punch portion. 16 . The molding apparatus according to claim 9 , wherein a mounting groove is defined in the die, and the auxiliary punch is mounted in the mounting groove.

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