Pouch molding apparatus

Abstract

A pouch molding apparatus according to the present invention, which is configured to mold a pouch including an accommodation part configured to accommodate an electrode assembly and a sealing part extending from the accommodation part, comprises a heat press configured to press the sealing part for the purpose of forming an unfolding part extending from the accommodation part and a folding part extending in a direction different from a direction in which the unfolding part extends by bending at least a portion of the sealing part, wherein the heat press comprises: a main heat press configured to press the folding part; and a sub-heat press configured to heat a hinge part connecting the unfolding part and the folding part while the main heat press presses the folding part, the sub-heat press extending in a direction different from the direction in which the main heat press extends.

Description

Pouch forming device

[0001] [Cross-reference with related applications]

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0119954, filed September 8, 2023, the entire disclosure of which is incorporated herein by reference.

[0003] [Technical Field]

[0004] The present invention relates to a pouch forming device. More specifically, the invention relates to a pouch forming device for forming a pouch that encloses an electrode assembly.

[0005] With the technological development and increasing demand for electric vehicles, mobile devices, and other devices, the demand for secondary batteries as an energy source is increasing. Unlike primary batteries, secondary batteries can be recharged and reused after a single use. A secondary battery consists of an anode and a cathode. When a metal is oxidized at the anode, electricity is generated by the movement of electrons released from the metal. The oxidized metal moves to the cathode through the electrolyte and is reduced.

[0006] To manufacture such a secondary battery, an electrode active material slurry is first applied to a positive electrode current collector and a negative electrode current collector to manufacture a positive electrode and a negative electrode, which are then laminated on both sides of a separator to form an electrode assembly. The electrode assembly is then housed in a battery case, filled with electrolyte, and sealed.

[0007] Secondary batteries are classified into pouch type and can type, depending on the material of the case that houses the electrode assembly. Pouch type secondary batteries are formed by housing the electrode assembly in a pouch made of a flexible polymer material. Can type secondary batteries are formed by housing the electrode assembly in a case made of a material such as metal or plastic.

[0008] The pouch, which is the battery case of a pouch-type secondary battery, is manufactured by forming a receiving portion by pressing a flexible pouch film. Once the receiving portion is formed, an electrode assembly is placed in the receiving space of the receiving portion, and the edges of the receiving portion are fused to form a sealing portion, thereby sealing the pouch.

[0009] At this time, the overall width of the secondary battery needs to be reduced to allow more secondary batteries to be loaded into the battery module case. To reduce the overall width of the secondary battery, the sealing portion provided at the edge of the pouch is folded to form a folding portion. However, because the folding portion is formed by folding the sealing portion, the folding portion may gradually unravel over time.

[0010] If the folding is released, interference may occur between the loaded secondary batteries, and the secondary batteries may come into contact with the battery module case in which they are housed, causing current to flow through the secondary batteries, which may result in heat generation in the secondary batteries. Therefore, to prevent this, it is necessary to prevent the folding of the folding portion from being released.

[0011] Furthermore, cracks may occur in the sealant layer of the pouch during the folding process of the folding portion. The pouch film may include a moisture barrier layer made of a material such as metal and a sealant layer made of a material such as polymer. If a crack occurs in the sealant layer, the electrolyte may come into contact with the moisture barrier layer, and in this case, current may flow into the moisture barrier layer, causing a current leakage. If a current leakage occurs, the secondary battery's power generation cannot be performed efficiently, and the user may be injured if they touch the secondary battery or its case, so this needs to be prevented.

[0012] The present invention has been devised to solve the above problems, and the object of the present invention is to provide a pouch forming device configured to prevent the folding of a folding portion formed by folding a sealing portion from being released in order to secure full-width fairness of a secondary battery.

[0013] Another object of the present invention is to provide a pouch forming device configured to prevent cracks in the hinge portion of a pouch from occurring while forming a folding portion by bending a sealing portion.

[0014] The technical problems to be achieved in this document are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0015] A pouch forming device according to one embodiment of the present invention is a pouch forming device configured to form a pouch including a receiving portion configured to receive an electrode assembly and a sealing portion extending from the receiving portion, the pouch forming device including a heat press configured to press the sealing portion to form an unfolding portion extending from the receiving portion by bending at least a portion of the sealing portion and a folding portion extending in a direction different from a direction in which the unfolding portion extends, the heat press including a main heat press configured to press the folding portion and a sub heat press configured to heat a hinge portion connecting the unfolding portion and the folding portion while the main heat press presses the folding portion, the sub heat press extending in a direction different from the direction in which the main heat press extends.

[0016] A pouch forming device according to one embodiment of the present invention includes a heat press configured to pressurize a pouch, the heat press including a main heat press and a sub heat press coupled to the main heat press and extending in a direction different from an extension direction of the main heat press.

[0017] The pouch forming device according to the present invention includes a heat press configured to heat a hinge portion connecting an unfolding portion and a folding portion of a pouch while the main heat press presses a folding portion of the pouch, thereby having the effect of preventing the folding portion from unfolding.

[0018] The pouch forming device according to the present invention is configured to heat the hinge portion so that the sealant layer of the hinge portion connecting the unfolding portion and the folding portion of the pouch flows, thereby preventing cracks from occurring in the hinge portion while the sealing portion is bent to form the folding portion.

[0019] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0020] FIG. 1 is a perspective view illustrating an electrode assembly according to one embodiment of the present invention being accommodated in a pouch.

[0021] Fig. 2 is a cross-sectional view showing the first sealing portion adjacent to the second sealing portion of the pouch illustrated in Fig. 1.

[0022] Fig. 3 is a perspective view showing that a folding portion is formed after the first sealing portion is bonded to the second sealing portion of the pouch shown in Fig. 1.

[0023] Figure 4 is a conceptual diagram illustrating a step of forming a folding portion using a conventional pouch forming device.

[0024] Figure 5 is a conceptual diagram illustrating a step of forming a folding portion through a pouch forming device of the present invention.

[0025] Fig. 6 is a perspective view illustrating a heat press of a pouch forming device according to the first embodiment heating a hinge portion of a pouch.

[0026] Fig. 7 is an enlarged cross-sectional view showing the heat press and secondary battery shown in Fig. 6 cut along line Ⅶ-Ⅶ'.

[0027] Fig. 8 is a perspective view illustrating the heat press illustrated in Fig. 6.

[0028] FIG. 9 is a perspective view illustrating a cooling unit of a pouch forming device according to the first embodiment cooling a hinge portion of a pouch.

[0029] Fig. 10 is an enlarged cross-sectional view showing the cooling unit and secondary battery shown in Fig. 9 taken along line Ⅹ-Ⅹ'.

[0030] Figure 11 is a perspective view illustrating the cooling unit illustrated in Figure 9.

[0031] Fig. 12 is an enlarged cross-sectional view illustrating a heat press and a secondary battery according to a second embodiment.

[0032] Fig. 13 is an enlarged cross-sectional view illustrating a heat press and a secondary battery according to a third embodiment.

[0033] Fig. 14 is an enlarged cross-sectional view illustrating a heat press and a secondary battery according to the fourth embodiment.

[0034] Hereinafter, with reference to the attached drawings, preferred embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be implemented in various different forms and is not limited or restricted by the following examples.

[0035] In order to clearly explain the present invention, a detailed description of a part that is irrelevant to the description or a related known technology that may unnecessarily obscure the gist of the present invention has been omitted, and when adding reference signs to components of each drawing in this specification, the same or similar reference signs are attached to the same or similar components throughout the specification.

[0036] In addition, terms and words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best way.

[0037] It should be understood that the various embodiments and terms used in this document are not intended to limit the technical features described in this document to specific embodiments, but rather to include various modifications, equivalents, or substitutes of the embodiments.

[0038] In connection with the description of the drawings, similar reference numerals may be used for similar or related components.

[0039] The singular form of a noun corresponding to an item may include one or more of said items, unless the relevant context clearly indicates otherwise.

[0040] In this document, each of the phrases "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" may include any one of the items listed together in that phrase, or all possible combinations thereof.

[0041] The term "and / or" includes any combination of a plurality of related described elements or any one of a plurality of related described elements.

[0042] Terms such as "first," "second," or "first" or "second" may be used simply to distinguish one component from another and do not qualify the components in any other respect (e.g., importance or order).

[0043] When a component (e.g., a first component) is referred to as being "coupled" or "connected" to another component (e.g., a second component), with or without the terms "functionally" or "communicatively," it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0044] The terms "include" or "have" are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in this document, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0045] When a component is said to be “connected,” “coupled,” “supported,” or “in contact with” another component, this includes not only cases where the components are directly connected, coupled, supported, or in contact, but also cases where the components are indirectly connected, coupled, supported, or in contact through a third component.

[0046] When we say that a component is "on" another component, this includes not only cases where the component is in contact with the other component, but also cases where there is another component between the two components.

[0047] Meanwhile, the terms “upper and lower directions,” “lower side,” and “front and rear directions” used in the following description are defined based on the drawings, and the shape and position of each component are not limited by these terms.

[0048] Specifically, as illustrated in FIG. 1, the direction in which the electrode assembly (10) moves to be accommodated in the accommodation space (910S) is defined as downward, the direction in which the electrode lead (12) extends is defined as forward, and the upper side, rear side, left and right sides can be defined based on this.

[0049] Alternatively, as illustrated in Fig. 3, the direction in which the electrode lead (12) extends is defined as forward, the direction in which the folding portion (922) extends from the unfolding portion (921) is defined as upward, and based on this, the rear, lower, left and right sides can be defined.

[0050] Hereinafter, embodiments according to the present invention will be described in detail with reference to the attached drawings.

[0051] Fig. 1 is a perspective view illustrating an electrode assembly (10) according to one embodiment of the present invention being accommodated in a pouch (900). Fig. 2 is a cross-sectional view illustrating a first sealing portion (920') adjacent to a second sealing portion (920'') of the pouch (900) illustrated in Fig. 1. Fig. 3 is a perspective view illustrating a folding portion (922) formed after a first sealing portion (920') is bonded to a second sealing portion (920'') of the pouch (900) illustrated in Fig. 1.

[0052] Referring to FIGS. 1 to 3, a secondary battery (1) according to one embodiment of the present disclosure is described.

[0053] A secondary battery (1) may include an electrode assembly (10). The electrode assembly (10) may be formed by alternately stacking electrodes (not shown) and separators (not shown). First, a slurry containing an electrode active material, a binder, and a plasticizer may be applied to a positive electrode current collector and a negative electrode current collector to manufacture electrodes such as a positive electrode and a negative electrode. Then, separators may be stacked between the electrodes to form an electrode assembly (10), and the electrode assembly (10) may be inserted into a battery case (not shown) and sealed after applying an electrolyte (20).

[0054] Specifically, the electrode assembly (10) may include two types of electrodes, a positive electrode and a negative electrode, and a separator interposed between the electrodes to mutually insulate the electrodes. This electrode assembly (10) may be provided in a stack type, a jelly roll type, a stack and folding type, etc., depending on the way in which the positive electrode, the negative electrode, and the separator are stacked. The two types of electrodes, i.e., the positive electrode and the negative electrode, may each have a structure in which an active material slurry is applied to an electrode current collector in the form of a metal foil or metal mesh containing aluminum and copper, respectively. The slurry may typically be formed by stirring a granular active material, an auxiliary conductor, a binder, a plasticizer, etc. in a state in which a solvent is added. The solvent in the slurry may be removed in a subsequent process.

[0055] More specifically, the positive electrode may include a positive electrode material with a strong oxidizing ability that provides electrons. For example, the positive electrode material may include lithium ions, a transition metal, and oxygen. Nickel, cobalt, or manganese may be used as the transition metal. The negative electrode may include a negative electrode material with a strong reducing ability that accepts electrons. For example, the negative electrode material may include graphite. When the secondary battery (1) is charged and discharged, electrons may move according to the movement of lithium ions. In this case, lithium ions may move through an electrolyte (20) (see FIG. 7) located between the positive electrode and the negative electrode, and electrons may move through a conductor connecting the positive electrode and the negative electrode.

[0056] For example, when a secondary battery (1) is being charged, lithium ions in the positive electrode move to the graphite in the negative electrode, receive electrons from the negative electrode, become lithium, and can move between each layer of the graphite. Since graphite has a structure including multiple layers, even if lithium is stored in the graphite, dendrites that form protruding shapes on the negative electrode may not be generated. When the secondary battery (1) is being discharged, lithium between the graphite in the negative electrode releases electrons and becomes lithium ions, which can move to the positive electrode through the electrolyte (20). When the lithium ions move to the positive electrode, they can combine with a transition metal. Since the transition metal can be in an ionic state with multiple charges, even if the transition metal combines with lithium ions and has a different charge than before, the ionic state is maintained, and structural stability can be maintained. However, this is just one example, and the ions that move while repeating charging and discharging may be sodium ions or other substances, not lithium ions. Furthermore, the material used as the negative electrode material may be a material other than graphite. Additionally, the electrolyte (20) may be in a liquid state, but a solid electrolyte (20) may also be used in the secondary battery (1) of the present disclosure.

[0057] As illustrated in FIG. 1, the electrode assembly (10) may include electrode tabs (11). The electrode tabs (11) are respectively connected to the positive and negative electrodes of the electrode assembly (10) and may protrude outwardly from the electrode assembly (10) to serve as a path through which electrons may move between the inside and the outside of the electrode assembly (10). The plurality of electrode tabs (11) may protrude in different directions of the electrode assembly (10) as illustrated in FIG. 1, but are not limited thereto, and the plurality of electrode tabs (11) may protrude in parallel in the same direction or may protrude in various directions.

[0058] The electrode assembly (10) may include an electrode lead (12) that is connected to an electrode tab (11) and supplies electricity to the outside of the secondary battery (1). The electrode lead (12) may be connected to the electrode tab (11) by spot welding, etc.

[0059] The electrode assembly (10) may include an insulating portion (13) surrounding a portion of the electrode lead (12). The insulating portion (13) may be positioned to correspond to a position where the first sealing portion (920') and the second sealing portion (920'') are fused together. When the first sealing portion (920') and the second sealing portion (920'') are fused together, the insulating portion (13) may be positioned between the first sealing portion (920') and the second sealing portion (920''), thereby bonding the electrode lead (12) to the pouch (900). In addition, the insulating portion (13) may prevent electricity generated from the electrode assembly (10) from flowing to the pouch (900) through the electrode lead (12), and maintain the sealing of the pouch (900). Therefore, the insulating portion (13) may be made of a non-conductive material that does not conduct electricity well. For example, the insulating member (13) may be an insulating tape that is easy to attach to the electrode lead (12) and has a relatively thin thickness. However, the present invention is not limited thereto, and various materials may be used as long as they can insulate the electrode lead (12).

[0060] The electrode tab (11) configured to have a positive electrode may be referred to as a positive electrode tab, the electrode tab (11) configured to have a negative electrode may be referred to as a negative electrode tab, the electrode lead (12) configured to have a positive electrode may be referred to as a positive electrode lead, and the electrode lead (12) configured to have a negative electrode may be referred to as a negative electrode lead. The electrode lead (12) may have one end connected to the electrode tab (11) and the other end protruding outward from the pouch (900). That is, the electrode lead (12) may include a positive lead having one end connected to the positive electrode tab and extending in the direction in which the positive electrode tab protrudes, and a negative lead having one end connected to the negative electrode tab and extending in the direction in which the negative electrode tab protrudes. Meanwhile, both the positive electrode lead and the negative electrode lead may have other ends protruding outward from the pouch (900). Accordingly, the positive electrode lead and the negative electrode lead may supply electricity generated inside the electrode assembly (10) to the outside. Additionally, the positive and negative tabs can each extend in different directions.

[0061] The positive and negative leads may be made of different materials. The positive lead may be made of the same aluminum material as the positive current collector, and the negative lead may be made of the same copper material as the negative current collector or of nickel-coated copper. Furthermore, a portion of the electrode lead (12) protruding from the outside of the pouch (900) may serve as a terminal portion and be electrically connected to an external terminal.

[0062] The pouch (900) can be manufactured from a highly flexible material to accommodate the electrode assembly (10) therein. When a flexible pouch film (901) is drawn and formed using a punch (not shown), a portion thereof is stretched to form a receiving portion (910) having a pocket-shaped receiving space (910S), thereby manufacturing the pouch (900). The pouch (900) can accommodate and seal the electrode assembly (10) such that a portion of the electrode lead (12) is exposed.

[0063] When forming a receiving portion (910) on a pouch film (901), only one receiving portion (910) may be formed on one pouch film (901), but the present invention is not limited thereto, and two receiving portions (910) may be drawn and formed adjacent to each other on one pouch film (901). Then, as illustrated in FIG. 1, two receiving portions (910) adjacent to each other may be formed. Each receiving portion (910) may have the same depth, but the present invention is not limited thereto, and the depths of each receiving portion (910) may be different from each other. After the electrode assembly (10) is accommodated in one receiving portion (910), the pouch (900) may be folded about an axis so that another receiving portion (910) faces the receiving portion (910). Accordingly, another receiving portion (910) may accommodate the electrode assembly (10) from the upper side. Since two receiving portions (910) accommodate one electrode assembly (10), an electrode assembly (10) having a thicker thickness can be accommodated than when there is only one receiving portion (910). In addition, since the pouch (900) is folded, the first sealing portion (920') and the second sealing portion (920'') are integrally connected, so that the number of sides to be sealed can be reduced when performing a sealing process later. Accordingly, the process speed can be improved and the number of sealing processes can be reduced.

[0064] When the electrode lead (12) is connected to the electrode tab (11) of the electrode assembly (10) and an insulating portion (13) is formed on a portion of the electrode lead (12), the electrode assembly (10) is accommodated in a receiving space (910S) provided in a receiving portion (910), and another receiving portion (910) can cover the electrode assembly (10). Thereafter, a portion of the first sealing portion (920') and the second sealing portion (920'') is sealed, and an electrolyte (20) can be injected into the receiving space (910S) through an unsealed opening between the first sealing portion (920') and the second sealing portion (920''). When the electrolyte (20) is injected, the space between the first sealing portion (920') and the second sealing portion (920'') can be sealed.

[0065] As illustrated in FIG. 2, the pouch film (901) forming the sealing portion (920) may include multiple layers.

[0066] The pouch film (901) may include a sealant layer (905) and a moisture barrier layer (904). The pouch film (901) may include a stretching aid layer (903) positioned on the moisture barrier layer (904) and a surface protection layer (902) positioned on the outer side of the stretching aid layer.

[0067] The sealant layer (905) is made of a first polymer and is formed as the innermost layer so as to be in direct contact with the electrode assembly (10). Here, the innermost layer refers to the layer located last when facing the direction in which the electrode assembly (10) is positioned based on the moisture barrier layer (904). Since the sealant layer (905) is in direct contact with the electrode assembly (10), it can have insulation properties, and since it is in contact with the electrolyte (20), it can have corrosion resistance. In addition, since the sealant layer (905) must completely seal the inside to block material movement between the inside and the outside, it can have high sealing properties. That is, the sealing portion (920) in which the sealant layers (905) are bonded to each other can have excellent thermal bonding strength. For example, the first polymer for manufacturing the sealant layer (905) may be formed of one or more materials selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymers, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyparaphenylenebenzobisoxazole, polyarylate, Teflon, and glass fiber. In particular, a polyolefin resin such as polypropylene or polyethylene may be mainly used. Polypropylene has excellent mechanical properties such as tensile strength, rigidity, surface hardness, wear resistance, and heat resistance, and chemical properties such as corrosion resistance, and thus may be mainly used for using the sealant layer (905). Furthermore, it may be formed of non-stretched polypropylene, acid-treated polypropylene, or a polypropylene-butylene-ethylene terpolymer. Here, the acid-treated polypropylene may be maleic anhydride polypropylene (MAH PP). In addition, the sealant layer (905) may have a single film structure made of a single material, or a composite film structure formed by layering two or more materials.

[0068] The thickness of the sealant layer (905) may be 60 μm to 100 μm, and in particular, 75 μm to 85 μm. If the thickness of the sealant layer (905) is thinner than 60 μm, a problem may occur in which the sealing durability is reduced, such as the interior of the sealant layer (905) being destroyed during sealing. Conversely, if the thickness of the sealant layer (905) is thicker than 100 μm, the thickness of the entire pouch (900) becomes excessively thick, so that the energy density per volume of the secondary battery (1) may actually decrease.

[0069] The moisture barrier layer (904) is laminated between the surface protection layer (902) and the sealant layer (905) to secure the mechanical strength of the pouch (900) and block the ingress of gas or moisture from the outside of the secondary battery (1), thereby preventing leakage of the electrolyte (20). The moisture barrier layer (904) may be made of a metal, and in particular, the moisture barrier layer (904) according to one embodiment of the present invention may be made of a metal including an aluminum alloy of the alloy number AA80XX series. Aluminum can secure a mechanical strength of a predetermined level or higher, while being light in weight and ensuring complementary electrochemical properties and heat dissipation properties by the electrode assembly (10) and the electrolyte (20). The aluminum alloy may include various materials. For example, it may include one or two or more selected from the group consisting of iron, copper, chromium, manganese, nickel, magnesium, and zinc.

[0070] The thickness of the moisture barrier layer (904) may be 50 μm to 80 μm, and in particular, 55 μm to 65 μm. If the thickness of the moisture barrier layer (904) is less than 50 μm, the formability may be reduced. In this case, when the pouch film (901) is draw-formed, there may be a limit to forming the outer wall of the receiving portion (910) close to vertical when the depth of the receiving portion (910) is formed deep. If the thickness of the moisture barrier layer (904) is thicker than 80 μm, not only the manufacturing cost increases, but also the thickness of the entire secondary battery (1) becomes excessively thick, which may cause a problem in that the energy density relative to the thickness of the secondary battery (1) decreases. If the thickness of the sealant layer (905) is reduced to be thinner than 60 μm in order to reduce the thickness of the entire secondary battery (1), a problem in that the sealing durability deteriorates may occur. Since the formability of the moisture barrier layer (904) according to one embodiment of the present invention is improved, when drawing-molding the pouch film (901), the depth of the receiving portion (910) can be formed deep while the outer wall of the receiving portion (910) can become closer to vertical. Then, since the volume of the receiving space (910S) increases, the volume of the electrode assembly (10) stored inside the receiving portion (910) can also increase, and the energy efficiency per volume of the secondary battery (1) can also increase. In addition, since the thickness of the sealant layer (905) is not reduced without significantly increasing the manufacturing cost, the thickness of the entire pouch (900) does not significantly increase, and the sealing durability may not be reduced.

[0071] The surface protection layer (902) is made of a second polymer and is formed on the outermost layer to protect the secondary battery (1) from friction and collision with the outside, while electrically insulating the electrode assembly (10) from the outside. Here, the outermost layer is the layer positioned last when facing in the opposite direction to the direction in which the electrode assembly (10) is positioned based on the moisture barrier layer (904). The second polymer for making the surface protection layer (902) may be one or more materials selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymers, polyacrylonitrile, polyimide, polyamide, cellulose, amide, nylon, polyester, polyparaphenylene benzobisoxazole, polyarylate, Teflon, and glass fiber. In particular, a polymer such as polyethylene terephthalate (PET), which mainly has wear resistance and heat resistance, may be often used. The surface protection layer (902) may have a single film structure made of one or more materials, or may have a composite film structure formed by forming layers of two or more materials.

[0072] The thickness of the surface protection layer (902) may be 5 μm to 25 μm, and in particular, 7 μm to 12 μm. If the thickness of the surface protection layer (902) is thinner than 5 μm, there may be a problem of reduced external insulation. Conversely, if the thickness of the surface protection layer (902) is thicker than 25 μm, the thickness of the entire pouch (900) becomes thicker, and thus the energy density per volume of the secondary battery (1) may be reduced.

[0073] Polyethylene terephthalate (PET) is inexpensive, durable, and has excellent electrical insulation properties. However, it has poor adhesion to aluminum, which is frequently used as a moisture barrier layer (904), and its behavior when stretched by applying stress may also differ. Therefore, if the surface protection layer (902) and the moisture barrier layer (904) are directly bonded, the surface protection layer (902) and the moisture barrier layer (904) may peel off during drawing molding. Consequently, the moisture barrier layer (904) may not be stretched uniformly, which may result in a problem of reduced formability.

[0074] The stretching auxiliary layer (903) can be made of a third polymer and laminated between the surface protection layer (902) and the moisture barrier layer (904). The stretching auxiliary layer (903) can be laminated between the surface protection layer (902) and the moisture barrier layer (904) to prevent the surface protection layer (902) and the moisture barrier layer (904) from being peeled off when being stretched. The third polymer for making the stretching auxiliary layer (903) can be one or more materials selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymers, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyparaphenylenebenzobisoxazole, polyarylate, Teflon, and glass fiber. In particular, since nylon resin readily adheres to the polyethylene terephthalate (PET) of the surface protection layer (902) and exhibits similar behavior when stretched to the aluminum alloy of the moisture barrier layer (904), nylon resin can be primarily used as the third polymer. In addition, the stretching auxiliary layer (903) can have a single film structure made of one material, or a composite film structure formed by layering two or more materials.

[0075] Since the moisture barrier layer (904) according to one embodiment of the present invention has a thickness of approximately 50 μm to 80 μm, particularly 55 μm to 65 μm, the formability of the moisture barrier layer (904) can be improved. In this case, the stretching aid layer (903) can have a thickness of 20 μm to 50 μm to improve the formability, particularly 25 μm to 38 μm. If the thickness of the stretching aid layer (903) is thinner than 20 μm, the stretching aid layer (903) may not follow the improved formability of the moisture barrier layer (904) and may be broken during stretching. Conversely, if it is thicker than 50 μm, the thickness of the entire pouch (900) becomes thicker, so that the volume of the secondary battery (1) may increase and the energy density may decrease. In particular, according to one embodiment of the present invention, the thickness ratio of the stretching auxiliary layer (903) and the moisture barrier layer (904) may be less than 1:2.5. However, if the thickness of the stretching auxiliary layer (1354) becomes excessively thick, the thickness of the entire pouch (900) also becomes thick, so that the thickness ratio may be greater than 1:1.5 to prevent excessive thickness. That is, the thickness ratio may be 1:1.5 to 1:2.5.

[0076] As illustrated in FIG. 2, the first sealing portion (920') can be positioned adjacent to the second sealing portion (920''). The first sealing portion (920') can be provided to be symmetrical with the second sealing portion (920''). Since the pouch film (901) is folded to form the first sealing portion (920') and the second sealing portion (920''), the first sealing portion (920') and the second sealing portion (920''), which are positioned on opposite sides based on the folded portion of the pouch film (901), can face each other and be symmetrical.

[0077] When the first sealing portion (920') and the second sealing portion (920'') are in contact with each other, the first sealant layer (905) of the first sealing portion (920') and the second sealant layer (905) of the second sealing portion (920'') can be in contact with each other. When heat is applied and pressure is applied after the first sealing portion (920') and the second sealing portion (920'') are in contact, the first sealant layer (905) of the first sealing portion (920') and the second sealant layer (905) of the second sealing portion (920'') can be melted and fused to each other. Since the first sealing portion (920') and the second sealing portion (920'') are positioned along the edge of the receiving portion (910), when the first sealing portion (920') and the second sealing portion (920'') are fused to each other, the edge of the receiving portion (910) can be sealed.

[0078] After the first sealing portion (920') and the second sealing portion (920'') are fused to each other, a degassing process, which is a process of removing gas remaining in the sealing portion (920), may be performed, and a trimming process, which cuts off unnecessary portions so that the sealing portion (920) has a predetermined width, may be performed. After the trimming process, the sealing portion (920) may have a predetermined width. A folding portion (922) may be formed by folding a portion of the sealing portion (920) in a bent manner.

[0079] As illustrated in FIG. 3, the sealing portion (920) may include an unfolding portion (921) extending from the receiving portion (910) and a folding portion (922) extending in a direction different from the extending direction of the unfolding portion (921). By forming the folding portion (922), the width of the portion of the pouch (900) extending outward from the receiving portion (910) may be narrowed. Accordingly, the volume occupied by the secondary battery (1) may be reduced, and thus the energy density per volume of the secondary battery (1) may be increased. Since the electrode leads (12) may be positioned at the front and rear of the pouch (900), the folding portion (922) may be provided at the left and right sides of the pouch (900) where it is easy to fold the sealing portion (920).

[0080] Figure 4 is a conceptual diagram illustrating a step in which a folding portion (922) is formed through a conventional pouch forming device (PA).

[0081] Referring to Fig. 4, a conventional pouch forming device (PA) and a process for forming a folding portion (922) using the same are described.

[0082] The pouch forming device (PA) may include a heat press (HP). The heat press (HP) may include a first heat press (HPa), a second heat press (HPb), a third heat press (HPc), a fourth heat press (HPd), and / or a fifth heat press (HPe), as illustrated in FIG. 4.

[0083] The process of forming the folding portion (922) of the conventional pouch (900) may be as follows.

[0084] First, referring to (a) of FIG. 4, the sealing portion (920) of the pouch (900) can be heated and pressed with a second heat press (HPb) (a trimming process for cutting the sealing portion (920) of the pouch (900) to an appropriate length may be performed first).

[0085] Thereafter, referring to (b) of FIG. 4, the third heat press (HPc) may be advanced upward to fold at least a portion of the sealing portion (920) of the pouch (900) relative to another portion. While the third heat press (HPc) folds the sealing portion (920) of the pouch (900), a folding knife (90) may be provided so that the folded portion of the sealing portion (920) of the pouch (900) is positioned between the third heat press (HPc) so that the extension direction of the folded portion of the sealing portion (920) of the pouch (900) faces upward. As illustrated in (b) of FIG. 4, the extension direction of the folded portion of the sealing portion (920) of the pouch (900) may have an angle of approximately 90° with respect to the extension direction of the portion of the sealing portion (920) of the pouch (900) extending from the receiving portion (910).

[0086] Thereafter, referring to (c) of FIG. 4, the fourth heat press (HPd) can pressurize the folded portion of the sealing portion (920) of the pouch (900) to come closer to the receiving portion (910) of the pouch (900) so that the extension direction of the folded portion of the sealing portion (920) of the pouch (900) is parallel to the extension direction of the non-folded portion. In other words, the fourth heat press (HPd) can move the end of the folded portion of the sealing portion (920) of the pouch (900) by 90° again. As illustrated in (c) of FIG. 4, the extension direction of the folded portion of the sealing portion (920) of the pouch (900) can have an angle of approximately 180° with respect to the extension direction of the portion of the sealing portion (920) of the pouch (900) extending from the receiving portion (910) of the pouch (900). Accordingly, the folded portion of the sealing portion (920) of the pouch (900) can be covered with the portion extending from the receiving portion (910) of the pouch (900).

[0087] Thereafter, referring to (d) of FIG. 4, the fifth heat press (HPe) is positioned on the upper and lower sides of the sealing portion (920) of the covered pouch (900), respectively, to heat and / or pressurize the sealing portion (920) of the covered pouch (900).

[0088] Thereafter, referring to (e) of FIG. 4, the conventional first heat press (HPa-0) can fold the sealing portion (920) of the heated, folded pouch (900) upward to form the folding portion (922) of the pouch (900). The conventional first heat press (HPa-0) is moved upward, and accordingly, the end of the sealing portion (920) of the folded pouch (900) can be moved 90°. While the conventional first heat press (HPa-0) folds the sealing portion (920) of the folded pouch (900), a folding knife (90) can be provided so that the folding portion (922) of the pouch (900) is positioned between the conventional first heat press (HPa-0) and the pouch so that the folding portion (922) of the pouch (900) faces upward.

[0089] Thereafter, referring to (f) of FIG. 4, the conventional first heat press (HPa-0) can heat and / or pressurize the folding portion (922) of the pouch (900) in a direction in which the folding portion (922) of the pouch (900) approaches the receiving portion (910) of the pouch (900). The conventional first heat press (HPa-0) can heat and / or pressurize the folding portion (922) of the pouch (900) by contacting the folding portion (922) of the pouch (900) for about 1.5 seconds.

[0090] Thereafter, referring to (g) of FIG. 4, a tape (80) may be provided to connect the folding portion (922) of the pouch (900) and the receiving portion (910) of the pouch (900) to fix the folding portion (922) of the pouch (900) in order to prevent the folding portion (922) of the pouch (900) from moving. The folding portion (922) of the pouch (900) may be taped to the receiving portion (910) of the pouch (900) by the tape (80). That is, at least a portion of the folding portion (922) of the pouch (900) may be taped. Accordingly, the sealing portion (920) of the pouch (900) of the secondary battery (1) may be made as close as possible to the receiving portion (910) of the pouch (900).

[0091] However, in the case of going through such a process, the folding part (922) of the pouch (900) that is not fixed by the tape (80) may move away from the receiving part (910) of the pouch (900). In particular, the pouch film (901) may include a moisture barrier layer (904), and the moisture barrier layer (904) may have a metal such as aluminum, so that a spring back phenomenon may occur to return to the shape before molding due to the elasticity of the metal. The portion of the folding part (922) of the pouch (900) that is not taped may move away from the receiving part (910) of the pouch (900). Accordingly, the folding part (922) of the pouch (900) may not be positioned consistently in the receiving part (910) of the pouch (900). In this case, since the folding portion (922) of the pouch (900) that is not taped is farther away from the receiving portion (910) of the pouch (900), the volume occupied by the secondary battery (1) increases, and when aligning a plurality of secondary batteries (1), the volume occupied by the secondary battery (1) per unit volume may increase. Furthermore, when a plurality of secondary batteries (1) are accommodated in a module case (not shown) with the folding portions (922) of the plurality of secondary batteries (1) facing upward or downward, the folding portion (922) of the pouch (900) is released, so that the folding portion (922) of the pouch (900) may come into contact with the top plate (not shown) of the module case (not shown) located above the folding portion (922) of the pouch (900). A current leak may occur in the top plate of the module case, and when the folding portion (922) of the pouch (900) comes into contact with the top plate of the module case, the current flowing in the top plate may flow to the electrode assembly (10) through the folding portion (922) of the pouch (900), causing the secondary battery (1) to malfunction. This phenomenon may be caused by the elasticity of the moisture barrier layer (904), or by the adhesion area (905b) of the sealant layer (905) that is formed while forming the sealing portion (920) of the pouch (900).When forming the sealing portion (920) of the pouch (900), the sealant layer (905) may be heated and / or pressurized. An area where the sealant layer (905) of the sealing portion (920) of the pouch (900) has a uniform thickness may be referred to as a sealing portion (905a), and an area where the sealant layer (905) has an uneven thickness may be referred to as a bonding portion (905b). Due to the bonding portion (905b), the entire folding portion (922) of the pouch (900) may be prevented from being bent at a preset angle. This is because when the bonding portion (905b) is thicker than the sealing portion (905a), the moisture barrier layer (904) positioned on the outside of the sealing portion (905a) may have a curvature, thereby inducing deformation of the entire folding portion (922) of the pouch (900) (see FIG. 7). Therefore, it is necessary to make the thickness of this attachment area (905b) constant.

[0092] Furthermore, when the sealant layer (905) is folded during the process of forming the folding portion (922) of the pouch (900), and when the sealant layer (905) is formed of polypropylene, polypropylene may be brittle, and thus cracks may occur during the process of folding the sealant layer (905). The sealant layer (905) has electrical insulation properties, and thus can prevent electricity generated in the electrode assembly (10) from moving to the moisture barrier layer (904). However, when a crack occurs in the sealant layer (905), the electrolyte (20) may move through the crack, and the electrolyte (20) and the moisture barrier layer (904) may meet. In this case, the electricity generated in the electrode assembly (10) may flow to the moisture barrier layer (904) through the electrolyte (20). The moisture barrier layer (904) may include a metal such as aluminum, and thus may conduct electricity. If electricity is conducted through the moisture barrier layer (904), there is a risk of electric shock if the user touches the secondary battery (1) or the battery module formed by stacking the secondary batteries (1).

[0093] Accordingly, in order to prevent this, during the process of forming the folding portion (922) of the conventional pouch (900), as shown in FIG. 4, a process of heating and pressurizing one side of the folding portion (922) of the pouch (900) can be performed with reference to FIG. 4 (e) and (f). This is because by heating and / or pressurizing the folding portion (922) of the pouch (900), any cracks in the sealant layer (905) that may have formed may be removed as the sealant layer (905) is heated due to the high temperature. However, as shown in the table below, when the outer surface of the folding portion (922) of the conventional pouch (900) is heated by contacting it with the first heat press (HPa), a problem may occur in which heat is not transferred to the sealant layer (905) of the hinge portion (923) of the pouch (900) (see FIG. 7) connecting the folding portion (922) of the pouch (900) and the unfolding portion (921) of the pouch (900) to the extent that cracks may disappear in the sealant layer (905).

[0094] Since bending occurs at the hinge portion (923) of the pouch (900), there is a high possibility that a crack will occur in the sealant layer (905) at the hinge portion (923) of the pouch (900). Therefore, it is necessary to apply heat to the sealant layer (905) at the hinge portion (923) of the pouch (900). Table 1 below is a table that summarizes the results of an experiment on the temperature change over time of the hinge portion (923) of the pouch (900) and the folding portion (922) of the pouch (900) while the heat press (HP) is in direct contact with the outer surface of the folding portion (922) of the pouch (900) at a temperature of 170°C.

[0095] Tact time (sec) Hinge (923) (℃) Folding (922) (℃) 026.8529.9127.130.8330.81061075.3121.6...5095.1119

[0096] As can be seen in Table 1 above, when the tact time, which is the time for the heat press (HP) and the outer surface of the folding portion (922) of the pouch (900) to come into contact with each other, is 3 seconds or less, the temperature of the hinge portion (923) of the pouch (900) may reach a temperature slightly higher than room temperature. At this temperature, it may be difficult to heat at least a portion of the sealant layer (905) of the hinge portion (923) of the pouch (900), and therefore, it may be difficult to eliminate cracks that have occurred in the hinge portion (923) of the pouch (900).

[0097] Furthermore, when increasing the tact time, the temperature of the hinge portion (923) of the pouch (900) can be increased. However, since an increase in the tact time means an increase in the process time, the hourly production volume may decrease, leading to a decrease in production efficiency. Therefore, it is necessary to increase the temperature of the hinge portion (923) of the pouch (900) without increasing the tact time.

[0098] FIG. 5 is a conceptual diagram illustrating a step of forming a folding portion (922) of a pouch (900) through a pouch forming device (PA) of the present invention.

[0099] Referring to FIG. 5, a pouch forming device (PA) according to one embodiment of the present invention and a process for forming a folding portion (922) of a pouch (900) using the same are described.

[0100] Among the processes of forming the folding portion (922) of the pouch (900) described with reference to FIG. 4, the descriptions of (a), (b), (c), and (d) of FIG. 4 can be equally applied to the pouch forming device (PA) of the present invention and the process of forming the folding portion (922) of the pouch (900) using the same.

[0101] As described above, the conventional first heat press (HPa-0) may have difficulty in transferring a large amount of heat to the hinge portion (923) of the pouch (900) because it does not directly heat the hinge portion (923) of the pouch (900). In order to solve this problem, the present invention can directly heat the hinge portion (923) of the pouch (900) while the first heat press (HPa) presses the folding portion (922) of the pouch (900).

[0102] As illustrated in (f) of FIG. 5, the first heat press (HPa) can contact the hinge portion (923) of the pouch (900) while simultaneously contacting the folding portion (922) of the pouch (900). Accordingly, the first heat press (HPa) can directly apply heat to the hinge portion (923) of the pouch (900). For this purpose, the first heat press (HPa) may include a protruding portion.

[0103] As illustrated in (e) of FIG. 5, the first heat press (HPa) can form a folding portion (922) of the pouch (900). The process of forming the folding portion (922) of the pouch (900) described with reference to (e) of FIG. 5 has the same principle as the process of forming the folding portion (922) of the pouch (900) described with reference to (e) of FIG. 4, but since the shape of the first heat press (HPa) is different from the prior art, there may be a difference from the prior art in the part where the sealing portion (920) of the pouch (900) is pressed to form the folding portion (922) of the pouch (900).

[0104] Furthermore, after applying heat to the hinge portion (923) of the pouch (900), the hinge portion (923) of the pouch (900) may be cooled by the cooling unit (CU), as illustrated in (g) of FIG. 5. The moisture barrier layer (904) and / or the sealant layer (905) may have a stronger plastic characteristic than an elastic characteristic when the temperature decreases. Accordingly, the occurrence of a spring back phenomenon in which the folding portion (922) of the pouch (900) moves away from the receiving portion (910) of the pouch (900) may be reduced. The secondary battery (1) together with the cooling unit (CU) may be moved to a location where the taping process is performed. However, the process of cooling the hinge portion (923) of the pouch (900) described with reference to (g) of FIG. 5 may be omitted depending on the embodiment.

[0105] Thereafter, as shown in (h) of FIG. 5, the folding portion (922) of the pouch (900) can be taped and fixed to the receiving portion (910) of the pouch (900). This may be the same as described with reference to (g) of FIG. 4.

[0106] Although the present invention has been described above as being applied only to the first heat press (HPa), this is merely for convenience of explanation. The present invention can be applied to the heat press (HP) as long as a method of forming a pouch (900) is used. Therefore, the invention's concept applied to the first heat press (HPa) will be described below as being applied to the heat press (HP).

[0107] In summary, the pouch forming device (PA) according to the present invention is configured to form a pouch (900) including a receiving portion (910) configured to receive an electrode assembly (10) and a sealing portion (920) extending from the receiving portion (910), and may include a heat press (HP) configured to press the sealing portion (920) of the pouch (900) to form an unfolding portion (921) of the pouch (900) extending from the receiving portion (910) of the pouch (900) and a folding portion (922) of the pouch (900) extending in a direction different from the extending direction of the unfolding portion (921) of the pouch (900). The heat press (HP) may include a main heat press (100) configured to pressurize a folding portion (922) of a pouch (900) and a sub heat press (200) configured to heat a hinge portion (923) of a pouch (900) connecting an unfolding portion (921) of the pouch (900) and a folding portion (922) of the pouch (900) while the main heat press (100) presses the folding portion (922) of the pouch (900) (see FIG. 7).

[0108] This is explained in more detail below.

[0109] Example 1

[0110] Fig. 6 is a perspective view illustrating a heat press (HP) of a pouch forming device (PA) according to the first embodiment heating a hinge portion (923) of a pouch (900). Fig. 7 is an enlarged cross-sectional view illustrating the heat press (HP) and secondary battery (1) illustrated in Fig. 6 taken along line VII-VII'. Fig. 8 is a perspective view illustrating the heat press (HP) illustrated in Fig. 6.

[0111] Referring to FIGS. 6 to 8, a heat press (HP) of a pouch forming device (PA) according to a first embodiment of the present invention and a secondary battery (1) formed thereby are described. For convenience of explanation, the following description assumes that the process referring to FIG. 5 (f) is being performed.

[0112] As illustrated in FIG. 6, the secondary battery (1) may include a pouch (900) including a receiving portion (910) configured to receive an electrode assembly (10) and a sealing portion (920) of the pouch (900) extending from the receiving portion (910) of the pouch (900). The pouch forming device (PA) may include a heat press (HP) configured to press the sealing portion (920) of the pouch (900) to form an unfolding portion (921) of the pouch (900) extending from the receiving portion (910) of the pouch (900) and a folding portion (922) of the pouch (900) extending in a direction different from the extending direction of the unfolding portion (921) of the pouch (900) by bending at least a portion of the sealing portion (920) of the pouch (900).

[0113] A heat press (HP) may be positioned to heat and / or pressurize the folding portion (922) of the pouch (900) toward the receiving portion (910) of the pouch (900). The heat press (HP) may be positioned on one side of the folding portion (922) of the pouch (900) and the folding knife (90) may be positioned on the other side so that the folding portion (922) of the pouch (900) extends at a preset angle with respect to the unfolding portion (921) of the pouch (900).

[0114] As illustrated in FIG. 7, the heat press (HP) may include a main heat press (100) configured to pressurize a folding portion (922) of a pouch (900). The heat press (HP) may include a sub heat press (200) configured to heat a hinge portion (923) of the pouch (900) connecting an unfolding portion (921) of the pouch (900) and a folding portion (922) of the pouch (900) while the main heat press (100) presses the folding portion (922) of the pouch (900). The sub heat press (200) may be coupled to the main heat press (100). However, the present invention is not limited thereto, and the sub heat press (200) may be formed integrally with the main heat press (100).

[0115] As illustrated in FIG. 8, the sub-heat press (200) may extend in a direction different from the extension direction of the main heat press (100). As illustrated in FIG. 7, when the extension direction of the main heat press (100) is considered to be the vertical direction, the sub-heat press (200) may extend to the right. More specifically, the sub-heat press (200) may have an "L" shape.

[0116] As illustrated in FIGS. 7 and 8, the main heat press (100) may have a pressing surface (100P) configured to press the folding portion (922) of the pouch (900). The pressing surface (100P) may be configured to contact the folding portion (922) of the pouch (900) to heat the folding portion (922) of the pouch (900). The pressing surface (100P) may prevent the folding portion (922) of the pouch (900) from moving away from the receiving portion (910) of the pouch (900). The pressing surface (100P) may extend parallel to the direction in which the outer surface of the folding portion (922) of the pouch (900) extends. However, without being limited thereto, the pressing surface (100P) does not press the folding portion (922) of the pouch (900), and only the folding heating surface (230P) of the sub-heat press (200) described below can press the folding portion (922) of the pouch (900). In this case, the description regarding the pressing surface (100P) can be applied as is to the folding heating surface (230P).

[0117] The sub-heat press (200) may have a hinge heating surface (210P) that contacts the hinge portion (923) of the pouch (900) while the pressing surface (100P) of the main heat press (100) contacts the folding portion (922) of the pouch (900). The hinge heating surface (210P) may be configured to contact the hinge portion (923) of the pouch (900) to heat the hinge portion (923) of the pouch (900). More specifically, the sub-heat press (200) may include a hinge heating portion (210) that is configured to contact the hinge portion (923) of the pouch (900) to directly transfer heat from the sub-heat press (200). The hinge heating portion (210) may have a hinge heating surface (210P) configured to come into contact with the hinge portion (923) of the pouch (900).

[0118] The hinge heating surface (210P) may be formed to correspond to the shape of the hinge portion (923) of the pouch (900). Since the hinge portion (923) of the pouch (900) is a bent portion, it may have a shape having a curvature, and when the hinge heating portion (210) has a hinge heating surface (210P) corresponding to the hinge portion (923) of the pouch (900), the hinge heating portion (210) may contact not only a part of the hinge portion (923) of the pouch (900), but the entire hinge portion (923) of the pouch (900). Therefore, heat generated in the hinge heating portion (210) can be efficiently transferred to the hinge portion (923) of the pouch (900). The hinge portion (923) of the pouch (900) can be configured so that the sealant layer (905) becomes flexible or reaches a temperature at which cracks disappear by the sub heat press (200) while the main heat press (100) presses the folding portion (922) of the pouch (900).

[0119] The hinge heating surface (210P) can be provided by bending between the folding heating surface (230P) and the unfolding heating surface (220P).

[0120] Since the hinge portion (923) of the pouch (900) can be positioned on the lower side of the folding portion (922) of the pouch (900), the hinge heating portion (210) can be positioned on the lower side of the pressing surface (100P) of the main heat press (100). Since the hinge portion (923) of the pouch (900) is a bent portion of the sealing portion (920) of the pouch (900) as the folding portion (922) of the pouch (900) is formed, the hinge portion (923) of the pouch (900) can extend further toward the receiving portion (910) of the pouch (900) than the folding portion (922) of the pouch (900). Accordingly, the hinge heating portion (210) can extend further toward the receiving portion (910) of the pouch (900) than the pressing surface (100P) of the main heat press (100).

[0121] The sub-heat press (200) may include an unfolding heating unit (220) extending from the hinge heating unit (210) to come into contact with the unfolding unit (921) of the pouch (900) to heat the unfolding unit (921) of the pouch (900). The unfolding heating unit (220) may extend toward the receiving unit (910) of the pouch (900). The unfolding unit (921) of the pouch (900) may be connected to the hinge unit (923) of the pouch (900). Therefore, when the unfolding unit (921) of the pouch (900) is heated, heat transferred to the unfolding unit (921) of the pouch (900) may be transferred to the hinge unit (923) of the pouch (900), thereby increasing the temperature of the hinge unit (923) of the pouch (900). While the unfolding heating unit (220) heats the unfolding unit (921) of the pouch (900), the temperature of the hinge unit (923) of the pouch (900) may increase.

[0122] The unfolding heating unit (220) may be positioned adjacent to the lower end of the main heat press (100) so as to be positioned below the unfolding unit (921) of the pouch (900) to prevent the unfolding unit (921) of the pouch (900) from moving toward the direction of gravity. The unfolding unit (921) of the pouch (900) may be supported by the unfolding heating unit (220), so that the angle between the unfolding unit (921) and the folding unit (922) of the pouch (900) may be formed to be close to a preset angle.

[0123] The unfolding heating portion (220) may have an unfolding heating surface (220P) that is provided to face the unfolding portion (921) of the pouch (900). The unfolding heating surface (220P) may extend perpendicularly to the extension direction of the pressurizing surface (100P). Since the extension direction of the folding portion (922) of the pouch (900) may be perpendicular to the unfolding portion (921) of the pouch (900), the unfolding heating surface (220P) may be perpendicular to the pressurizing surface (100P) so as to maintain a preset angle of the unfolding portion (921) of the pouch (900) with respect to the folding portion (922) of the pouch (900).

[0124] The unfolding heating surface (220P) can extend at a predetermined angle with respect to the direction of gravity and in a direction perpendicular to the direction of gravity. As illustrated in FIG. 7, the unfolding heating surface (220P) can extend at a predetermined angle with respect to the left and right directions. Accordingly, the unfolding portion (921) of the pouch (900) supported by the unfolding heating portion (220) can extend at a predetermined angle with respect to the extension direction of the receiving portion (910) of the pouch (900). As illustrated in FIG. 7, the unfolding portion (921) of the pouch (900) can extend upwards toward the right. That is, the folding heating surface (230P) described below can extend at a predetermined angle with respect to the vertical direction. The sealing portion (920) of the pouch (900) can be deformed to sag in the direction of gravity due to the influence of gravity. If the unfolding portion (921) of the pouch (900) extends in a direction intersecting the direction perpendicular to the direction of gravity from the time of initial molding, even if the unfolding portion (921) of the pouch (900) is deformed in the future by gravity, the extension direction of the unfolding portion (921) of the pouch (900) can be arranged to be approximately horizontal. Accordingly, the folding portion (920) can extend parallel to the direction of gravity.

[0125] The sub-heat press (200) may include a folding heating unit (230) extending from the hinge heating unit (210) to contact the folding unit (922) of the pouch (900) to heat the folding unit (922) of the pouch (900). Accordingly, the sub-heat press (200) may heat and / or pressurize all of the folding unit (922) of the pouch (900), the hinge unit (923) of the pouch (900), and the unfolding unit (921) of the pouch (900).

[0126] The folding heating unit (230) may have a folding heating surface (230P) configured to be in contact with the folding portion (922) of the pouch (900) to heat the folding portion (922) of the pouch (900). The folding heating surface (230P) may be parallel to the pressurizing surface (100P). Accordingly, the sub-heat press (200) may cover the main heat press (100) and a portion of the sealing portion (920) of the pouch (900).

[0127] Furthermore, as illustrated in FIG. 7, when the folding portion (922) of the pouch (900) includes a first folding portion (922a) extending from the unfolding portion (921) of the pouch (900), a second folding portion (922b) facing the first folding portion (922a), and a third folding portion (922c) connecting the first folding portion (922a) and the second folding portion (922b), the folding heating surface (230P) can heat and / or pressurize the outer surface of the first folding portion (922a). In other words, the sub heat press (200) may be configured to heat the hinge portion (923) of the pouch (900) while the first folding portion (922a) extending from the unfolding portion (921) of the pouch (900) and further away from the receiving portion (910) of the pouch (900) than the second folding portion (922b) positioned adjacent to the receiving portion (910) of the pouch (900) is pressed toward the receiving portion (910) of the pouch (900) by the main heat press (100).

[0128] As described above, the relationship between the sub-heat press (200) and the hinge portion (923) of the pouch (900) can be viewed from the perspective of a protruding shape, but as described below, it can also be viewed from the perspective of space.

[0129] The sub-heat press (200) can define a hinge heating space (200S) that can accommodate the hinge portion (923) of the pouch (900) by extending in a different direction from the main heat press (100). The hinge heating space (200S) can be provided to correspond to the shape of the hinge portion (923) of the pouch (900). The hinge heating space (200S) can be concave in a direction away from the hinge portion (923) of the pouch (900) so as to correspond to the hinge portion (923) of the pouch (900).

[0130] When viewing the sub-heat press (200) from the perspective of the hinge heating space (200S), the hinge heating space (200S) can be viewed as a groove. For example, as illustrated in FIG. 7, when a conventional heat press (HP) has the shape of a rectangular parallelepiped block, the heat press (HP) according to the present invention can be formed by forming a hinge heating space (200S) in the rectangular parallelepiped. That is, the hinge heating space (200S) can be formed by forming a groove in the conventional heat press (HP).

[0131] As described above, the hinge heating space (200S) can be provided so that the folding heating surface (230P) and the unfolding heating surface (220P) have a vertical relationship, while the folding heating surface (230P) is inclined with respect to the corner of the press.

[0132] Additionally, the sub-heat press (200) can be coupled to the main heat press (100) so as to be detachable from the main heat press (100). Accordingly, in the event of a breakdown of the sub-heat press (200), service can be provided by replacing only the sub-heat press (200) without having to replace the entire heat press (HP).

[0133] Fig. 9 is a perspective view illustrating a cooling unit (CU) of a pouch forming device (PA) according to the first embodiment cooling a hinge portion (923) of a pouch (900). Fig. 10 is an enlarged cross-sectional view illustrating the cooling unit (CU) and the secondary battery (1) illustrated in Fig. 9 taken along line Ⅹ-Ⅹ'. Fig. 11 is a perspective view illustrating the cooling unit (CU) illustrated in Fig. 9.

[0134] Referring to FIGS. 9 to 11, a cooling unit (CU) of a pouch forming device (PA) according to a first embodiment of the present invention and a secondary battery (1) formed thereby are described. For convenience of explanation, the following description assumes that the process referring to FIG. 5 (g) is being performed.

[0135] After the folding portion (922) of the pouch (900) is formed to extend at a preset angle relative to the extending direction of the unfolding portion (921) of the pouch (900), as described with reference to FIGS. 6 to 8, the hinge portion (923) of the pouch (900) can be cooled by a cooling unit (CU), as illustrated in FIG. 9. The sealant layer (905) of the hinge portion (923) of the pouch (900) can be heated at least partially or made fluid while the hinge portion (923) of the pouch (900) is in contact with the heat press (HP). If the sealant layer (905) is made fluid, it is easier to deform than when the sealant layer (905) is solidified, and thus the shape of the moisture barrier layer (904) can be more easily changed by the force that tries to deform it. Therefore, when the hinge portion (923) of the pouch (900) is heated and then cooled again, the spring back phenomenon in which the folding portion (922) of the pouch (900) returns to its shape before being formed can be prevented.

[0136] The cooling unit (CU) may be configured to contact the hinge portion (923) of the pouch (900) so that the hinge portion (923) of the pouch (900) releases heat. In other words, after the folding portion (922) of the pouch (900) is formed, the cooling unit (CU) may be configured to cool the sealing portion (920) of the pouch (900) to prevent the angle between the unfolding portion (921) of the pouch (900) and the folding portion (922) of the pouch (900) from changing. The cooling unit (CU) may include cooling fins (500) to release heat of the cooling unit (CU) to the outside of the cooling unit (CU). A plurality of cooling fins (500) may be provided to increase the surface area of ​​the cooling unit (CU). Heat transferred from the hinge portion (923) of the pouch (900) to the cooling unit (CU) can be transferred to the outside of the cooling unit (CU) through the cooling fin (500). In other words, the cooling fin (500) can be configured to release heat from the sealing portion (920) of the pouch (900).

[0137] The folding portion (922) of the pouch (900) may have one side in contact with the cooling unit (CU) and the other side in contact with the folding knife (90) to prevent deformation of the molded shape. The folding portion (922) of the pouch (900) is positioned between the cooling unit (CU) and the folding knife (90), so that deformation of the shape can be prevented.

[0138] As illustrated in FIG. 10, the cooling unit may include a main cooling unit (300) configured to support a folding portion (922) of a pouch (900). The cooling unit (CU) may include a sub-cooling unit (400) configured to cool a hinge portion (923) of the pouch (900) that connects the unfolding portion (921) and the folding portion (922) of the pouch (900) while the main cooling unit (300) supports the folding portion (922) of the pouch (900). The sub-cooling unit (400) may be coupled to the main heat press (100). However, the present invention is not limited thereto, and the sub-cooling unit (400) may be formed integrally with the main cooling unit (300).

[0139] As illustrated in FIG. 11, the sub-cooling unit (400) may extend in a direction different from the extension direction of the main cooling unit (300). When the extension direction of the main cooling unit (300) is considered to be the vertical direction, the sub-cooling unit (400) may extend to the right. More specifically, the sub-cooling unit (400) may have an "L" shape.

[0140] The main cooling unit (300) may include a plurality of cooling fins (500). The cooling fins (500) may increase the surface area of ​​the main cooling unit (300). The heat of the hinge portion (923) of the pouch (900) may be transferred to the main cooling unit (300) through the sub cooling unit (400) and may be transferred to the outside of the cooling unit (CU) through the cooling fins (500) of the main cooling unit (300).

[0141] The shape of the main cooling unit (300) may correspond to the shape of the main heat press (100) described with reference to FIGS. 6 to 8, and the shape of the sub cooling unit (400) may correspond to the shape of the sub heat press (200) described with reference to FIGS. 6 to 8. This is because the shape of the folding portion (922) of the pouch (900) formed by the heat press (HP) folding the sealing portion (920) of the pouch (900) may be the same as the shape of the folding portion (922) of the pouch (900) that the cooling unit (CU) intends to maintain. Therefore, the following description of the main cooling unit (300) and the sub cooling unit (400) may correspond to the description of the main heat press (100) and the sub heat press (200).

[0142] As illustrated in FIGS. 10 and 11, the main cooling unit (300) may have a support surface (300P) configured to support the folding portion (922) of the pouch (900). The support surface (300P) may be configured to contact the folding portion (922) of the pouch (900) to support the folding portion (922) of the pouch (900). The support surface (300P) may prevent the folding portion (922) of the pouch (900) from moving away from the receiving portion (910) of the pouch (900). The support surface (300P) may extend parallel to the direction in which the outer surface of the folding portion (922) of the pouch (900) extends.

[0143] The sub-cooling unit (400) may have a hinge cooling surface (410P) that contacts the hinge portion (923) of the pouch (900) while the pressurizing surface (100P) of the main cooling unit (300) contacts the folding portion (922) of the pouch (900). The hinge cooling surface (410P) may be configured to contact the hinge portion (923) of the pouch (900) to cool the hinge portion (923) of the pouch (900). More specifically, the sub-cooling unit (400) may include a hinge cooling portion (410) that is configured to contact the hinge portion (923) of the pouch (900) to directly transfer heat from the sub-cooling unit (400). The hinge cooling unit (410) may have a hinge cooling surface (410P) configured to come into contact with the hinge unit (923) of the pouch (900).

[0144] The hinge cooling surface (410P) may be formed to correspond to the shape of the hinge portion (923) of the pouch (900). Since the hinge portion (923) of the pouch (900) is a bent portion, it may have a shape having a curvature, and when the hinge cooling portion (410) has a hinge cooling surface (410P) corresponding to the hinge portion (923) of the pouch (900), the hinge cooling portion (410) may contact not only a part of the hinge portion (923) of the pouch (900), but the entire hinge portion (923) of the pouch (900). Therefore, heat generated in the hinge cooling portion (410) can be efficiently transferred to the hinge portion (923) of the pouch (900). The hinge portion (923) of the pouch (900) can be configured to reach a temperature at which the sealant layer (905) is not deformed by the sub cooling unit (400) while the main cooling unit (300) supports the folding portion (922) of the pouch (900).

[0145] The hinge cooling surface (410P) can be provided by bending between the folding cooling surface (430P) and the unfolding cooling surface (420P).

[0146] Since the hinge portion (923) of the pouch (900) can be positioned on the lower side of the folding portion (922) of the pouch (900), the hinge cooling portion (410) can be positioned on the lower side of the pressurized surface (100P) of the main cooling unit (300). Since the hinge portion (923) of the pouch (900) is a bent portion of the sealing portion (920) of the pouch (900) as it forms the folding portion (922) of the pouch (900), the hinge portion (923) of the pouch (900) can extend further toward the receiving portion (910) of the pouch (900) than the folding portion (922) of the pouch (900). Accordingly, the hinge cooling portion (410) can extend further toward the receiving portion (910) of the pouch (900) than the pressurized surface (100P) of the main cooling unit (300).

[0147] The sub-cooling unit (400) may include an unfolding cooling unit (420) extending from the hinge cooling unit (410) to come into contact with the unfolding unit (921) of the pouch (900) to cool the unfolding unit (921) of the pouch (900). The unfolding cooling unit (420) may extend toward the receiving unit (910) of the pouch (900). The unfolding unit (921) of the pouch (900) may be connected to the hinge unit (923) of the pouch (900). Therefore, when cooling the unfolding unit (921) of the pouch (900), heat may be transferred from the hinge unit (923) of the pouch (900) to the unfolding unit (921) of the pouch (900), thereby lowering the temperature of the hinge unit (923) of the pouch (900). While the unfolding cooling unit (420) cools the unfolding unit (921) of the pouch (900), the temperature of the hinge unit (923) of the pouch (900) may decrease.

[0148] The unfolding cooling unit (420) may be positioned adjacent to the lower end of the main cooling unit (300) so as to be positioned below the unfolding unit (921) of the pouch (900) to prevent the unfolding unit (921) of the pouch (900) from moving toward the direction of gravity. The unfolding unit (921) of the pouch (900) may be supported by the unfolding cooling unit (420), so that the angle between the unfolding unit (921) and the folding unit (922) of the pouch (900) may be formed to be close to a preset angle.

[0149] The unfolding cooling portion (420) may have an unfolding cooling surface (420P) that is arranged to face the unfolding portion (921) of the pouch (900). The unfolding cooling surface (420P) may extend perpendicularly to the extension direction of the pressurizing surface (100P). Since the extension direction of the folding portion (922) of the pouch (900) may be perpendicular to the unfolding portion (921) of the pouch (900), the unfolding cooling surface (420P) may be perpendicular to the pressurizing surface (100P) to maintain a preset angle with respect to the folding portion (922).

[0150] The sub-cooling unit (400) may include a folding cooling unit (430) extending from the hinge cooling unit (410) to come into contact with the folding unit (922) of the pouch (900) to cool the folding unit (922) of the pouch (900). Accordingly, the sub-cooling unit (400) may cool and / or support all of the folding unit (922) of the pouch (900), the hinge unit (923) of the pouch (900), and the unfolding unit (921) of the pouch (900).

[0151] The folding cooling unit (430) may have a folding cooling surface (430P) configured to be in contact with the folding portion (922) of the pouch (900) to heat the folding portion (922) of the pouch (900). The folding cooling surface (430P) may be parallel to the pressurizing surface (100P). Accordingly, the sub-cooling unit (400) may cover a portion of the main cooling unit (300) and the sealing portion (920) of the pouch (900).

[0152] Furthermore, as illustrated in FIG. 10, when the folding portion (922) of the pouch (900) includes a first folding portion (922a) extending from the unfolding portion (921) of the pouch (900), a second folding portion (922b) facing the first folding portion (922a), and a third folding portion (922c) connecting the first folding portion (922a) and the second folding portion (922b), the folding cooling surface (430P) can cool and / or support the outer surface of the first folding portion (922a). In other words, the sub-cooling unit (400) may be configured to cool the hinge portion (923) of the pouch (900) while the first folding portion (922a) extending from the unfolding portion (921) of the pouch (900) and further away from the receiving portion (910) of the pouch (900) than the second folding portion (922b) positioned adjacent to the receiving portion (910) of the pouch (900) supports the receiving portion (910) of the pouch (900) by the main cooling unit (300).

[0153] Since the sub-cooling unit (400) is a part that comes into contact with the hinge portion (923) of the pouch (900), when the cooling unit (CU) moves to a position where it comes into contact with the hinge portion (923) of the pouch (900) and is taped, vibration may occur in the cooling unit (CU). The vibration generated in the cooling unit (CU) may impact the hinge portion (923) of the pouch (900), which may cause cracks to occur in the hinge portion (923) of the pouch (900), and thus, this needs to be prevented. The sub-cooling unit (400) may therefore have an elastic material. More specifically, the sub-cooling unit (400) may include a silicone material to prevent impact from being transmitted to the hinge portion (923) of the pouch (900). Furthermore, the sub-cooling unit (400) needs to have elasticity to prevent impact from being applied to the hinge portion (923) of the pouch (900), while ensuring smooth heat transfer from the hinge portion (923) of the pouch (900) to the outside of the cooling unit (CU). Accordingly, the sub-cooling unit (400) may have a silicone composite material. The sub-cooling unit (400) may have a Silicone Based Conductive Elastomer.

[0154] As described above, the relationship between the sub-cooling unit (400) and the hinge portion (923) of the pouch (900) can be viewed from the perspective of a protruding shape, but as described below, it can also be viewed from the perspective of space.

[0155] The sub-cooling unit (400) may define a hinge cooling space (400S) capable of accommodating the hinge portion (923) of the pouch (900) by extending in a different direction from the main cooling unit (300). The hinge cooling space (400S) may be provided to correspond to the shape of the hinge portion (923) of the pouch (900). The hinge cooling space (400S) may be concave in a direction away from the hinge portion (923) of the pouch (900) so as to correspond to the hinge portion (923) of the pouch (900).

[0156] When viewing the sub cooling unit (400) from the perspective of the hinge cooling space (400S), the hinge cooling space (400S) can be viewed as a home.

[0157] As described above, the hinge cooling space (400S) can be arranged so that the folding cooling surface (430P) and the unfolding cooling surface (420P) have a vertical relationship, while the folding cooling surface (430P) is inclined with respect to the corner of the cooling unit (CU).

[0158] Additionally, the sub cooling unit (400) can be coupled to the main cooling unit (300) so as to be detachable from the main cooling unit (300). Accordingly, when the sub cooling unit (400) breaks down, service can be performed by replacing only the sub cooling unit (400) without having to replace the entire cooling unit (CU).

[0159] The cooling unit (CU) described above may not be included in the pouch forming device (PA). For convenience, the embodiment including the heat press (HP) and the cooling unit (CU) is referred to as the first embodiment, but the embodiment including the cooling unit (CU) and the embodiment not including the cooling unit (CU) can be viewed as separate embodiments. Furthermore, as illustrated in (f) of FIG. 5, after forming the folding portion (922) of the pouch (900), the hinge portion (923) of the pouch (900) can be cooled, as illustrated in (g) of FIG. 5, without the heat press (HP) heating and / or pressurizing the folding portion (922) of the pouch (900) and the sealing portion (920) of the pouch (900). Simply by performing the process using the cooling unit (CU), springback of the folding portion (922) of the pouch (900) can be prevented.

[0160] Below, embodiments different from the first embodiment will be described. Commonalities with the first embodiment will be omitted as much as possible, and the other embodiments will be described focusing on differences. In other words, it should be clear that any details not described in the second, third, and fourth embodiments can be supplemented by the first embodiment.

[0161] Second Example

[0162] Fig. 12 is an enlarged cross-sectional view showing a heat press (HP) and a secondary battery (1) according to the second embodiment.

[0163] Referring to Fig. 12, the present invention according to the second embodiment will be described.

[0164] The heat press (HP) according to the second embodiment differs from the first embodiment in that the sub heat press (200-1) does not come into contact with the folding portion (922) of the pouch (900). The outer surface of the folding portion (922) of the pouch (900) can come into contact with the pressing surface (100P) of the main heat press (100-1). The pressing surface (100P) of the main heat press (100-1) can come into contact with the entire outer surface of the folding portion (922). As in the first embodiment, when the pressing surface (100P) of the main heat press (100) and the folding heating surface (230P) of the sub heat press (200) are in contact with the outer surface of the folding part (922), the pressing surface (100P) of the main heat press (100) and the folding heating surface (230P) of the sub heat press (200) need to be aligned within the same plane so that the outer surface of the folding part (922) forms a plane. In order for the two surfaces having different configurations to be aligned within the same plane, the tolerance in the process needs to be reduced, which may result in a lot of production costs in production. However, as in the second embodiment, when only the pressing surface (100P) of the main heat press (100-1) presses the outer surface of the folding part (922), there is no need to align the two surfaces having different configurations within one plane, so that the process can be simplified.

[0165] The sub-heat press (200-1) according to the second embodiment may include a hinge heating part (210-1) configured to be in contact with the hinge part (923) of the pouch (900). The hinge heating part (210-1) may protrude from the main heat press (100-1). The hinge heating part (210-1) may be provided to correspond to the hinge part (923) of the pouch (900).

[0166] The sub-heat press (200-1) according to the second embodiment may include an unfolding heating unit (220-1) extending from a hinge unit (923) of a pouch (900). The unfolding heating unit (220-1) may extend in a direction different from the direction in which the main heat press (100-1) extends. The unfolding heating unit (220-1) may extend perpendicular to the direction in which the main heat press (100-1) extends.

[0167] The cooling unit (CU) according to the second embodiment can correspond to the heat press (HP) according to the second embodiment. That is, the main cooling unit (300) and the sub cooling unit (400) according to the second embodiment can correspond to the main heat press (100-1) and the sub heat press (200-1) according to the second embodiment.

[0168] Third Example

[0169] Fig. 13 is an enlarged cross-sectional view showing a heat press (HP) and a secondary battery (1) according to the third embodiment.

[0170] Referring to Fig. 13, the present invention according to the third embodiment will be described.

[0171] The main heat press (100-2) and the sub heat press (200-2) according to the third embodiment are different from the main heat press (100) and the sub heat press (200) according to the first embodiment in that they are formed integrally. That is, the sub heat press (200-2) according to the third embodiment can be extended from the main heat press (100-2). When the main heat press (100-2) and the sub heat press (200-2) are formed integrally, it may not be necessary to form the main heat press (100-2) and the sub heat press (200-2) separately when manufacturing the heat press (HP). The heat press (HP) having a single block shape can be formed, and a groove in which the hinge portion (923) of the pouch (900) can be accommodated can be formed in the heat press (HP), thereby manufacturing the hinge heating space (200S). In this case, the heat press (HP) manufacturing process is simplified, and the heat press (HP) manufacturing time can be shortened.

[0172] The cooling unit (CU) according to the third embodiment can correspond to the heat press (HP) according to the third embodiment. That is, the main cooling unit (300) and the sub cooling unit (400) according to the third embodiment can correspond to the main heat press (100-2) and the sub heat press (200-2) according to the third embodiment.

[0173] Example 4

[0174] Fig. 14 is an enlarged cross-sectional view showing a heat press (HP) and a secondary battery (1) according to the fourth embodiment.

[0175] Referring to Fig. 14, the present invention according to the fourth embodiment is described.

[0176] The heat press (HP) according to the fourth embodiment differs from the heat press (HP) of the first embodiment in that the angle formed by the pressurizing surface (100P) and the unfolding heating surface (220P-3) is not perpendicular. Since the pressurizing surface (100P) and the folding heating surface (230P) may be positioned within the same plane, the folding heating surface (230P) may not form a perpendicular angle with the unfolding heating surface (220P-3). That is, the angle on the side where the hinge portion (923) of the pouch (900) is positioned between the pressurizing surface (100P) and the unfolding heating surface (220P-3) may be an acute angle.

[0177] If the spring back phenomenon of the folding portion (922) is not completely prevented, the folding portion (922) may move away from the receiving portion (910) of the pouch (900) over time. In order for the folding portion (922) to extend perpendicular to the extending direction of the unfolding portion (921) of the pouch (900), the folding portion (922) may extend at an acute angle with the extending direction of the unfolding portion (921) of the pouch (900). As the spring back phenomenon of the folding portion (922) occurs over time, the folding portion (922) may become perpendicular to the extending direction of the unfolding portion (921) of the pouch (900). In other words, the initial folding portion (922) is arranged to be positioned close to the receiving portion (910) of the pouch (900), and as time passes, the folding portion (922) moves away from the receiving portion (910) of the pouch (900), so that the folding portion (922) can be spaced apart from the receiving portion (910) of the pouch (900) by a preset distance.

[0178] The cooling unit (CU) according to the fourth embodiment can correspond to the heat press (HP) according to the fourth embodiment. That is, the main cooling unit (300) and the sub cooling unit (400) according to the fourth embodiment can correspond to the main heat press (100-3) and the sub heat press (200-3) according to the fourth embodiment.

[0179] A pouch forming device (PA) and / or a secondary battery (1) according to one embodiment of the present invention may have the following characteristics.

[0180] A pouch forming apparatus (PA) according to one embodiment of the present invention is configured to form a pouch (900) including a receiving portion (910) of a pouch (900) configured to receive an electrode assembly (10) and a sealing portion (920) of the pouch (900) extending from the receiving portion (910) of the pouch (900), wherein the pouch forming apparatus (PA) may include a heat press (HP) configured to press the sealing portion (920) of the pouch (900) to form an unfolding portion (921) of the pouch (900) extending from the receiving portion (910) of the pouch (900) by bending at least a portion of the sealing portion (920) of the pouch (900) and a folding portion (922) extending in a direction different from the extending direction of the unfolding portion (921) of the pouch (900). The heat press (HP) may include a main heat press (100) configured to pressurize the folding portion (922). The heat press (HP) may include a sub heat press (200) configured to heat a hinge portion (923) of the pouch (900) connecting the unfolding portion (921) and the folding portion (922) of the pouch (900) while the main heat press (100) presses the folding portion (922), and may include a sub heat press (200) extending in a direction different from the extension direction of the main heat press (100).

[0181] The sub-heat press (200) can define a hinge heating space (200S) that can accommodate the hinge portion (923) of the pouch (900).

[0182] The hinge heating space (200S) may be concave in a direction away from the hinge portion (923) of the pouch (900) so as to correspond to the hinge portion (923) of the pouch (900).

[0183] The sub-heat press (200) may include a hinge heating unit (210) configured to be in contact with the hinge unit (923) of the pouch (900) so that the hinge unit (923) of the pouch (900) directly receives heat from the sub-heat press (200).

[0184] The sub-heat press (200) may further include an unfolding heating unit (220) extending from the hinge heating unit (210) to contact the unfolding unit (921) of the pouch (900) to heat the unfolding unit (921) of the pouch (900).

[0185] The unfolding heating unit (220) may be adjacent to the lower end of the main heat press (100) so as to be positioned below the unfolding unit (921) of the pouch (900) to prevent the unfolding unit (921) of the pouch (900) from moving toward the direction of gravity.

[0186] The main heat press (100) may have a pressing surface (100P) configured to come into contact with the folding portion (922) of the pouch (900) to heat the folding portion (922) of the pouch (900). The sub heat press (200) may have an unfolding heating surface (220P) configured to come into contact with the unfolding portion (921) of the pouch (900) to heat the unfolding portion (921) of the pouch (900). The sub heat press (200) may have a hinge heating surface (210P) configured to come into contact with the hinge portion (923) of the pouch (900) to heat the hinge portion (923) of the pouch (900).

[0187] The unfolding heating surface (220P) can be extended at an angle of 90° or less with respect to the extension direction of the pressurized surface (100P).

[0188] The unfolding heating surface (220P) can extend perpendicularly to the extension direction of the pressurized surface (100P).

[0189] The sub-heat press (200) may include a folding heating unit (230) extending from the hinge heating unit (210) to contact the folding unit (922) of the pouch (900) to heat the folding unit (922) of the pouch (900).

[0190] The main heat press (100) may have a pressing surface (100P) configured to come into contact with the folding portion (922) of the pouch (900) in order to heat the folding portion (922) of the pouch (900). The folding heating portion (230) may have a folding heating surface (230P) configured to come into contact with the folding portion (922) of the pouch (900) in order to heat the folding portion (922) of the pouch (900), and may have a folding heating surface (230P) that is parallel to the pressing surface (100P).

[0191] The sub heat press (200) may be configured to heat the hinge portion (923) of the pouch (900) while the first folding portion (922a) extending from the unfolding portion (921) of the pouch (900) and further away from the receiving portion (910) of the pouch (900) than the second folding portion (922b) positioned adjacent to the receiving portion (910) of the pouch (900) is pressed toward the receiving portion (910) of the pouch (900) by the main heat press (100).

[0192] The sub heat press (200) can be combined with the main heat press (100) so as to be separable from the main heat press (100).

[0193] After the folding portion (922) of the pouch (900) is formed, a cooling unit (CU) configured to cool the sealing portion (920) of the pouch (900) may be further included to prevent a change in the angle between the unfolding portion (921) of the pouch (900) and the folding portion (922) of the pouch (900). The cooling unit (CU) may include a main cooling unit (300) configured to support the folding portion (922) of the pouch (900), and may include a main cooling unit (300) including cooling fins (500) configured to release heat of the sealing portion (920) of the pouch (900). The cooling unit (CU) may include a sub-cooling unit (400) coupled with the main cooling unit (300) and defining a hinge cooling space (400S) that can accommodate the hinge portion (923) of the pouch (900).

[0194] The sub-cooling unit (400) may include a silicone material to prevent impact from being transmitted to the hinge portion (923) of the pouch (900).

[0195] A pouch forming device (PA) according to one embodiment of the present invention includes a heat press (HP) configured to pressurize a pouch (900), and the heat press (HP) may include a main heat press (100) and a sub heat press (200) coupled to the main heat press (100) and extending in a direction different from the extension direction of the main heat press (100).

[0196] The sub-heat press (200) can define a concave hinge heating space (200S) toward the center of the main heat press (100).

[0197] The sub-heat press (200) may have a folding heating surface (230P) positioned toward the hinge heating space (200S) and an unfolding heating surface (220P) having an angle of 90° or less with respect to the folding heating surface (230P).

[0198] The sub-heat press (200) may have a hinge heating surface (210P) bent between a folding heating surface (230P) and an unfolding heating surface (220P).

[0199] The main heat press (200) may have a pressing surface (100P) configured to be positioned on the same plane as the plane formed by extending the folding heating surface (230P).

[0200] Unless explicitly stated otherwise, the embodiments described above may be combined with other embodiments. Alternatively, combinations between embodiments may be considered possible, unless one embodiment is explicitly restricted from being combined with another embodiment. Combinations of one embodiment with another embodiment are deemed to be disclosed in this document.

[0201] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and various embodiments are possible within the scope equivalent to the technical idea of ​​the present invention and the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0202] [Explanation of symbols]

[0203] 1: Secondary battery

[0204] 10: Electrode assembly

[0205] 900: Pouch

[0206] 910: Reception

[0207] 920: Sealing Department

[0208] 921: Unfolding section

[0209] 922: Folding section

[0210] 922a: First folding section

[0211] 922b: Second folding section

[0212] 923c: Third folding section

[0213] 923: Hinge

[0214] PA: Pouch forming device

[0215] HP: Heat Press

[0216] 100: Main hit press

[0217] 100P: Pressurized cotton

[0218] 200: Sub-hit press

[0219] 200S: Hinge heating space

[0220] 210: Hinge heating part

[0221] 210P: Hinge heating surface

[0222] 220: Unfolding heating section

[0223] 220P: Unfolding heating surface

[0224] 230: Folding heating section

[0225] 230P: Folding heating surface

[0226] CU: Cooling Unit

[0227] 300: Main cooling unit

[0228] 300P: Support surface

[0229] 400: Sub-cooling unit

[0230] 400S: Hinge Cooling Space

[0231] 410: Hinge cooling unit

[0232] 410P: Hinge Cooling Surface

[0233] 420: Unfolding cooling unit

[0234] 420P: Unfolding cooling surface

[0235] 430: Folding cooling unit

[0236] 430P: Folding Cooling Surface

[0237] 500: Cooling fins

Claims

1. A pouch forming device configured to form a pouch including a receiving portion configured to receive an electrode assembly and a sealing portion extending from the receiving portion, A heat press configured to press the sealing portion to form an unfolding portion extending from the receiving portion and a folding portion extending in a direction different from the direction in which the unfolding portion extends by bending at least a portion of the sealing portion, The above heat press, A main heat press configured to pressurize the above folding portion; and A pouch forming device comprising a sub-heat press configured to heat a hinge portion connecting the unfolding portion and the folding portion while the main heat press presses the folding portion, the sub-heat press extending in a direction different from the extension direction of the main heat press.

2. In paragraph 1, The above sub-heat press is a pouch forming device that defines a hinge heating space that can accommodate the hinge portion of the pouch.

3. In paragraph 2, A pouch forming device in which the hinge heating space is concave in a direction away from the hinge portion of the pouch so as to correspond to the hinge portion of the pouch.

4. In paragraph 1, The above sub-heat press is a pouch forming device including a hinge heating unit configured to contact the hinge portion of the pouch so that the hinge portion directly receives heat from the sub-heat press.

5. In paragraph 4, A pouch forming device wherein the sub-heat press further includes an unfolding heating section extending from the hinge heating section to contact the unfolding section to heat the unfolding section.

6. In paragraph 5, A pouch forming device in which the unfolding heating unit is positioned adjacent to the lower end of the main heat press so as to be positioned below the unfolding unit of the pouch to prevent the unfolding unit of the pouch from moving toward the direction of gravity.

7. In paragraph 1, The above main heat press has a pressing surface configured to contact the folding portion of the pouch to heat the folding portion of the pouch, The above sub-heat press is, An unfolding heating surface configured to contact the unfolding portion of the pouch to heat the unfolding portion of the pouch; and A pouch forming device having a hinge heating surface configured to come into contact with the hinge portion of the pouch to heat the hinge portion of the pouch.

8. In paragraph 7, A pouch forming device in which the above-mentioned unfolding heating surface extends at an angle of 90° or less with respect to the extension direction of the above-mentioned pressing surface.

9. In paragraph 7, A pouch forming device in which the above-mentioned unfolding heating surface extends perpendicularly to the extension direction of the above-mentioned pressing surface.

10. In paragraph 4, A pouch forming device wherein the sub-heat press includes a folding heating unit extending from the hinge heating unit to contact the folding unit of the pouch to heat the folding unit of the pouch.

11. In paragraph 10, The above main heat press has a pressing surface configured to contact the folding portion of the pouch to heat the folding portion of the pouch, A pouch forming device having a folding heating surface configured to come into contact with the folding portion of the pouch in order to heat the folding portion of the pouch, the folding heating surface being parallel to the pressing surface.

12. In paragraph 1, A pouch forming device configured to heat the hinge portion of the pouch while the sub-heat press is pressed toward the receiving portion by the main heat press, the first folding portion extending from the unfolding portion of the pouch and further away from the receiving portion than the second folding portion positioned adjacent to the receiving portion.

13. In paragraph 1, A pouch forming device in which the sub-heat press is coupled to the main heat press so as to be separable from the main heat press.

14. In paragraph 1, After the folding portion of the pouch is formed, a cooling unit is further included to cool the sealing portion of the pouch to prevent the angle between the unfolding portion of the pouch and the folding portion of the pouch from changing. The above cooling unit, A main cooling unit configured to support the folding portion of the pouch, the main cooling unit including cooling fins configured to release heat from the sealing portion; and A pouch forming device comprising a sub-cooling unit coupled to the main cooling unit and defining a hinge cooling space that can accommodate the hinge portion of the pouch.

15. In paragraph 14, The above sub-cooling unit is a pouch forming device including a silicone material to prevent impact from being transmitted to the hinge portion.

16. Includes a heat press configured to pressurize the pouch, The above heat press, Main heat press; and A pouch forming device comprising a sub-heat press coupled to the main heat press and extending in a direction different from the extension direction of the main heat press.

17. In paragraph 16, The above sub-heat press is a pouch forming device that defines a concave hinge heating space toward the center of the above main heat press.

18. In paragraph 17, The above sub-heat press is, A folding heating surface positioned toward the above hinge heating space; and A pouch forming device having an unfolding heating surface having an angle of 90° or less with respect to the above folding heating surface.

19. In paragraph 18, The above sub-heat press is a pouch forming device having a hinge heating surface bent between the folding heating surface and the unfolding heating surface.

20. In paragraph 18, The above main heat press is a pouch forming device having a pressing surface configured to be positioned on the same plane as the plane formed by extending the above folding heating surface.

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