Pouch-type battery case and lithium secondary battery comprising same

Abstract

A pouch-type battery case according to the present invention comprises: a cup portion having an accommodation space in which an electrode assembly is accommodated; a terrace portion formed along the circumference of the accommodation space; and a gas discharge portion, wherein the gas discharge portion comprises at least one through-hole formed in the cup portion or the terrace portion, and a gas-permeable film covering the through-hole, the gas-permeable film is sealed in the battery case, forming a sealing area around the through-hole, and the gas discharge portion has an anti-venting index (AVI) of 3.0 or less. In the case of a gas discharge portion that satisfies the anti-venting index, gas is smoothly discharged due to a relatively low operating pressure, and durability is excellent due to a high full venting pressure, and thus a pouch-type secondary battery having improved safety and lifespan can be provided.

Description

Pouch-type battery case and pouch-type secondary battery including the same The present invention relates to a pouch-type battery case and a pouch-type secondary battery including the same, and more specifically, to a pouch-type battery case including a gas discharge unit that allows smooth gas discharge and has excellent durability, and a pouch-type secondary battery including the same. Secondary batteries are used in a wide range of fields, from small products such as digital cameras, P-DVDs, MP3Ps, mobile phones, PDAs, portable game devices, power tools, and e-bikes, to large products requiring high output such as electric vehicles and hybrid cars, to power storage devices that store surplus power generation or renewable energy, and to backup power storage devices. Types of secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, lithium ion batteries, and lithium ion polymer batteries. Secondary batteries can be manufactured by housing an electrode assembly in which a cathode, an anode, and a separator interposed therebetween are alternately laminated, in a battery case, injecting an electrolyte, and then sealing the battery case. Secondary batteries are classified into pouch types and can types depending on the material of the case housing the electrode assembly. Among them, a pouch type battery can be manufactured by performing press processing on a flexible pouch film laminate to form a cup portion, housing an electrode assembly in the inner accommodation space of the cup portion, and sealing the sealing portion. Pouch-type secondary batteries have a problem in that gas may be generated inside the pouch when operated at high temperatures, overcharged, or when a short circuit occurs, and when the gas pressure inside the pouch increases, the pouch may vent and explode or catch fire. In order to solve the above problem, a component that can continuously discharge gas without stopping the battery operation is essential. Research is actively being conducted to install a gas discharge component configured as a valve to discharge gas generated inside the battery. However, most valve-type gas discharge components are composed of heavy materials, and the problem of swelling due to gas generation is often not resolved because the operating pressure is high. Accordingly, a gas discharge component is being developed that prevents the movement of moisture and electrolyte while allowing only gas to pass through by deforming the lead film of the electrode lead portion or forming a hole by punching a part of the battery case and then sealing it with a film that only allows gas to pass through. However, in the case of films that can only transmit gas as described above, depending on the material applied, if the gas permeability is excellent, the possibility of liquid penetration also increases, adhesion to the battery case may become a problem, and if the possibility of liquid penetration is attempted to be reduced to zero, there is a problem that the desired level of gas discharge performance is not realized. In addition, there is a problem that gas discharge performance, pressure at which operation begins, and venting pressure vary depending on the dimensional characteristics of the components forming the gas discharge part, and since it has not been clearly identified what dimensions become variables that can affect gas discharge performance, in-depth research is required to implement a gas discharge part with excellent performance. The present invention is intended to solve the above problems, and by precisely designing a through hole connecting the inside and outside of the case forming the gas discharge portion and a gas-permeable film covering the through hole, an anti-venting index is defined, thereby providing a pouch-type battery case that is easy to discharge gas while also being durable enough to withstand high internal pressure. In addition, the present invention is intended to solve the above problems, and to provide a pouch-type secondary battery with excellent safety and improved lifespan by applying the pouch-type battery case. [1] According to one embodiment of the present invention, a pouch-type battery case including a cup portion having a receiving space for accommodating an electrode assembly; a terrace portion formed along a periphery of the receiving portion; and a gas discharge portion; wherein the gas discharge portion is provided at at least one position among the cup portion and the terrace portion, each of the gas discharge portions includes at least one through hole and a gas-permeable film covering the through hole, the gas-permeable film is sealed to the battery case to form a sealing area around the through hole, and the gas discharge portion has an anti-venting index (AVI) defined by the following Equation 1 of 3.0 or less. [Formula 1] AVI = [A h xr h ] / [W s x C h ] In the above equation 1, A h is the total cross-sectional area of ​​the above through hole (mm 2 ) is a unitless number, and r h is a unit of the average radius (mm) of the above through-holes, and W s is a unitless number of the average width (mm) of the above sealing area, and C h is a unitless number of the total circumference (mm) of the above through hole. [2] In the above [1], the anti-venting index (AVI) may be 0.10 to 2.50. [3] In the above [1] and / or [2], the gas discharge portion may have a ratio of the average width of the sealing area to the average radius of the through hole of 0.45 to 3.00. [4] In at least one of the above [1] to [3], the gas discharge portion may have a ratio of the total cross-sectional area of ​​the through hole to the total circumference of the through hole of 0.25 mm to 2.50 mm. [5] In at least one of the above [1] to [4], the gas discharge portion may be formed at one or more locations selected from among the terrace portion and the cup portion adjacent to the terrace portion and not in contact with the electrode assembly inside. [6] In at least one of the above [1] to [5], the number of through holes may be 1 to 6. [7] In at least one of the above [1] to [6], the total cross-sectional area (A) of the through hole H ) is 5 mm 2 25 mm inside 2 It could be. [8] In at least one of the above [1] to [7], the thickness of the gas permeable film may be 80 to 500 ㎛. [9] In at least one of the above [1] to [8], the gas permeable film may be disposed inside the battery case.

[0010] In at least one of the above [1] to [9], the gas-permeable film may include an adhesive resin layer in contact with the battery case and a permeable resin layer disposed on the adhesive resin layer.

[0011] In the above

[0010] , the adhesive resin layer may include a non-fluorinated polyolefin resin.

[0012] In at least one of the above

[0010] and / or

[0011] , the permeable resin layer may include a fluorinated polyolefin resin.

[0013] In at least one of the above

[0010] to

[0012] , the thickness (T) of the permeable resin layer T ) The thickness (T) of the adhesive resin layer A ) ratio (T A / T T ) can be between 0.4 and 2.0.

[0014] In at least one of the above [1] to

[0013] , the pouch-shaped battery case may have a structure in which a substrate layer, a gas barrier layer, and a sealant layer are sequentially laminated from the outside.

[0015] According to another embodiment of the present invention, a pouch-type secondary battery is provided, comprising: an electrode assembly; a pouch-type battery case as described above; an electrode lead connected to the electrode assembly and protruding to the outside of the pouch-type battery case via the terrace portion; and a lead film disposed between the electrode lead and the pouch-type battery case on the terrace portion; wherein a portion of the terrace portion is sealed along a periphery of the cup portion to form a sealing portion. The pouch-shaped battery case according to the present invention defines an anti-venting index through the design dimensions of a through hole connecting the inside and outside of the case forming a gas discharge portion and a gas-permeable film covering the through hole, thereby implementing a pouch-shaped battery case having a gas discharge portion that is easy to discharge gas while also being durable enough to withstand high internal pressure. In addition, the pouch-type secondary battery according to the present invention can contribute to improving the lifespan by having excellent safety and improved durability by applying the pouch-type battery case. The drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the contents of the invention described above, serve to further understand the technical idea of ​​the present invention; therefore, the present invention should not be interpreted as being limited to matters described in such drawings. Figure 1 is an exploded assembly diagram of a pouch-type secondary battery. Figure 2 is a plan view of a pouch-type secondary battery. Figure 3 is a cross-sectional view of a portion of a pouch-type secondary battery having a gas discharge section. Figure 4 is an enlarged cross-sectional view of a portion of a pouch-type secondary battery having a gas discharge portion. Figure 5 is a plan view of a pouch-type secondary battery having multiple gas discharge ports formed therein. Figure 6 is an enlarged plan view of a pouch-type secondary battery for area A of Figure 5. Figure 7 is an enlarged plan view of a pouch-type secondary battery for a portion of area A of Figure 5. Figure 8 is an enlarged plan view of a pouch-type secondary battery for a portion of area A of Figure 5. The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and the present embodiments are provided only to make the disclosure of the present invention complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification. Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with a meaning that can be commonly understood by a person of ordinary skill in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries shall not be ideally or excessively interpreted unless explicitly specifically defined. The terminology used herein is for the purpose of describing embodiments only and is not intended to limit the invention. In this specification, the singular also includes the plural unless specifically stated otherwise. The terms "comprises" and / or "comprising" as used herein do not exclude the presence or addition of one or more other components in addition to the components mentioned. In this specification, when it is said that a part includes a certain component, this does not mean that other components are excluded, but rather that other components may be included, unless otherwise specifically stated. The term “A and / or B” in this specification means A, or B, or A and B. In this specification, “%” means weight percent unless otherwise explicitly indicated. The pouch-type battery case and pouch-type secondary battery described in this specification include at least one of the technical configurations described below, and may include any combination between technically possible configurations among the technical configurations below. Pouch-type battery case First embodiment A pouch-shaped battery case according to a first embodiment comprises a cup portion having a receiving space for accommodating an electrode assembly; a terrace portion formed along a periphery of the receiving portion; and a gas discharge portion, wherein the gas discharge portion is provided at at least one position among the cup portion and the terrace portion, each of the gas discharge portions including at least one through hole and a gas-permeable film covering the through hole, the gas-permeable film being sealed to the battery case to form a sealing region around the through hole, and the gas discharge portion is characterized in that an anti-venting index (AVI) defined by the following Equation 1 is 3.0 or less. [Formula 1] AVI = [A h xr h ] / [W s x C h ] In the above equation 1, A h is the total cross-sectional area of ​​the above through hole (mm 2 ) is a unitless number, and r h is a unit of the average radius (mm) of the above through-holes, and W sis a unitless number of the average width (mm) of the above sealing area, and C h is a unitless number of the total circumference (mm) of the above through hole. In general, the gas discharge performance of a gas discharge part is determined by the properties of the material constituting the gas discharge part, and depending on the properties of the material, the moisture penetration prevention performance and the electrolyte leakage prevention performance can be determined, and the gas permeability is also a property that varies depending on the material, and the material constituting the gas discharge part plays an important role. However, considering that although materials play an important role, there are clearly areas that are not determined by materials, and that there are factors that can improve gas discharge performance regardless of materials, in the first embodiment, a gas discharge portion that can withstand high internal pressure and has excellent discharge performance is introduced through the definition of an anti-venting index when gas is discharged through a through hole formed in a pouch-type battery case. Specifically, when gas is discharged through the through holes in the gas discharge portion, depending on the number of through holes formed and the increase in the total cross-sectional area of ​​the formed through holes, the gas discharge can be performed smoothly, but as the internal pressure increases, the ability to withstand it may vary depending on the total circumference of the formed through holes. In addition, the smaller the average radius of the through holes, the greater the tension due to the gas generated inside is received, making it difficult to withstand high internal pressure, but based on the same cross-sectional area, installing multiple through holes with small average radii can be advantageous for the internal pressure, and also, by increasing the width of the sealing area, it is possible to respond to high internal pressure. In this way, implementing a gas discharge unit that can withstand high internal pressure, discharge gas from the beginning of generation, and even has excellent discharge performance can be derived from a considerably complex relationship, and depending on the dimensions, installing a single through hole and installing multiple through holes are also complex, so the anti-venting index can be defined by reflecting these various factors. FIG. 1 is an exploded assembly diagram of a pouch-type secondary battery (100), FIG. 2 is a plan view of the pouch-type secondary battery (100), FIG. 3 is a cross-sectional view of a portion of a pouch-type battery case of the pouch-type secondary battery in which a gas discharge portion is provided, and FIG. 4 is an enlarged cross-sectional view of a portion of a pouch-type battery case of the pouch-type secondary battery in which a gas discharge portion is provided. In FIG. 2, some of the components of the pouch-type secondary battery (100) are omitted for convenience of understanding. As illustrated in FIGS. 1 to 4, the pouch-type secondary battery (100) of the present invention includes a pouch-type battery case (110) including a gas discharge portion (200) according to the present invention, an electrode assembly (160), an electrode lead (180), and a lead film (190). Referring to FIGS. 1 to 4 above, the pouch-type battery case (110) and pouch-type secondary battery (100) of the present invention will be described. In one aspect, the pouch-shaped battery case (110) includes a cup portion (122, 132) having a receiving space in which an electrode assembly (160) is accommodated; a terrace portion (150) formed along a periphery of the cup portion (122, 132); and a gas discharge portion (200) having one or more through holes (220) and a gas-permeable film (210) to close the through holes. Battery Case The above pouch-shaped battery case (110) can accommodate an electrode assembly (160) in an inner receiving space. The pouch-shaped battery case (110) can be manufactured by molding a pouch film laminate. In this case, as illustrated in FIG. 4, the pouch-shaped battery case can include a substrate layer (111), a gas barrier layer (112), and a sealant layer (113). The substrate layer (111), the gas barrier layer (112), and the sealant layer (113) can be sequentially laminated. The substrate layer (111) is formed on the outermost layer of the pouch film laminate to protect the secondary battery from friction and collision with the outside. The substrate layer is made of polymer and can electrically insulate the electrode assembly from the outside. The substrate layer (111) may be made 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, polyparaphenylene benzobisoxazole, polyarylate, Teflon, and glass fiber. Preferably, the substrate layer may be made of polyethylene terephthalate (PET), nylon, or a combination thereof, which have wear resistance and heat resistance. The substrate layer (111) may have a single film structure made of a single material. Alternatively, the substrate layer (111) may have a composite film structure formed by forming layers of two or more materials. The thickness of the substrate layer (111) may be 5 ㎛ to 50 ㎛, specifically 7 ㎛ to 40 ㎛, and more specifically 25 ㎛ to 38 ㎛. When the thickness of the substrate layer satisfies the above range, the external insulation is excellent, and the thickness of the entire pouch is not thick, so the energy density per volume of the secondary battery can be excellent. The gas barrier layer (112) is laminated between the substrate layer (111) and the sealant layer (113) to secure the mechanical strength of the pouch, block the ingress of gas or moisture from outside the secondary battery, and prevent electrolyte leakage from inside the pouch-type battery case. The gas barrier layer (112) may be formed of a metal, and specifically, may be formed of an aluminum alloy thin film. When the gas barrier layer (112) is formed using an aluminum alloy thin film, a mechanical strength higher than a predetermined level can be secured, while being light in weight and securing electrochemical properties and heat dissipation properties by the electrode assembly and the electrolyte. The aluminum alloy thin film may include at least one selected from the group consisting of metal elements other than aluminum (Al), for example, iron (Fe), copper (Cu), chromium (Cr), manganese (Mn), nickel (Ni), magnesium (Mg), silicon (Si), and zinc (Zn). The thickness of the gas barrier layer (112) may be 40 ㎛ to 100 ㎛, specifically 50 ㎛ to 90 ㎛, and more specifically 55 ㎛ to 85 ㎛. When the thickness of the gas barrier layer (112) satisfies the above range, the formability and gas barrier performance are excellent when forming the cup part. The sealant layer (113) is intended to completely seal the inside of the pouch-shaped battery case by mutually thermally bonding the sealing portion when the pouch-shaped battery case containing the electrode assembly inside is sealed. To this end, the sealant layer (113) may be formed of a material having excellent thermal bonding strength. The sealant layer (113) may be formed of a material having insulating, corrosion-resistant, and sealing properties. Specifically, since the sealant layer (113) is in direct contact with the electrode assembly and / or the electrolyte inside the pouch-shaped battery case, it may be formed of a material having insulating and corrosion-resistant properties. In addition, since the sealant layer (113) must completely seal the inside of the pouch-shaped battery case to block material movement between the inside and the outside, it may be formed of a material having high sealing properties (e.g., excellent thermal bonding strength). In order to secure such insulating, corrosion-resistant, and sealing properties, the sealant layer (113) may be formed of a polymer material. The sealant layer (113) may be made 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, and preferably may be made of a polyolefin resin such as polypropylene (PP) and / or polyethylene (PE). In this case, the polypropylene may be composed of cast polypropylene (CPP), acid modified polypropylene (Acid Modified Polypropylene, PPa), a polypropylene-ethylene copolymer, and / or a polypropylene-butylene-ethylene terpolymer. The thickness of the sealant layer (113) may be 30 ㎛ to 130 ㎛, specifically 50 ㎛ to 120 ㎛, and more specifically 70 ㎛ to 100 ㎛. When the thickness of the sealant layer (113) satisfies the above range, there is an effect of securing the sealing strength of the sealing portion while also securing the formability of the pouch film laminate. The pouch film laminate may be drawn and stretched by a punch or the like to manufacture a pouch-shaped battery case (110). As a result, the pouch-shaped battery case (110) may include a cup portion (122) and a receiving portion (124). The receiving portion (124) is a place for receiving an electrode assembly, and may mean a receiving space formed in a pocket shape on the inside of the cup portion (122) as the cup portion (122) is formed. According to one embodiment of the present invention, a pouch-type battery case (110) may include a first case (120) and a second case (130) as illustrated in FIG. 1. The first case (120) includes a receiving portion (124) capable of receiving an electrode assembly (160), and the second case (130) may cover the receiving portion (124) from above to prevent the electrode assembly (160) from being separated from the outside of the battery case (110). The first case (120) and the second case (130) may be manufactured such that one side thereof is connected to each other as illustrated in FIG. 1, but are not limited thereto and may be manufactured in various ways, such as being manufactured separately from each other. When forming a cup portion on a pouch film laminate, two symmetrical cup portions (122, 132) can be drawn and formed adjacent to each other on one pouch film laminate. In this case, cup portions (122, 132) can be formed on each of the first case (120) and the second case (130) as illustrated in FIG. 1. After the electrode assembly (160) is accommodated in the receiving portion (124) provided in the cup portion (122) of the first case (120), the bridge portion (140) formed between the two cup portions (122, 132) can be folded so that the two cup portions (122, 132) face each other. In this case, the cup portion (132) of the second case (130) can accommodate the electrode assembly (160) from above. Accordingly, since two cup parts (122, 132) accommodate one electrode assembly (160), an electrode assembly (160) having a thicker thickness can be accommodated than when there is only one cup part (122). In addition, since one corner of the secondary battery (100) is formed by folding the pouch-type battery case (110), the number of corners to be sealed can be reduced when performing a sealing process later. Accordingly, the process speed of the pouch-type secondary battery (100) can be improved, and the number of sealing processes can be reduced. The pouch-type battery case (110) can be sealed while housing the electrode assembly (160) so that a part of the electrode lead (180) described later, i.e., a terminal part, is exposed, as shown in FIG. 2. Specifically, when the electrode lead (180) is connected to the electrode tab (170) of the electrode assembly (160) and a lead film (190) is formed on a part of the electrode lead (180), the electrode assembly (160) can be housed in the receiving portion (124) provided in the cup portion (122) of the first case (120), and the second case (130) can cover the receiving portion (124) from above. Then, as shown in FIG. 2, an electrolyte can be injected into the receiving portion (124), and a part of the terrace portion (150) formed along the perimeter of the first case (120) and the second case (130) can be sealed to form a sealing portion (151). The sealing portion (151) can perform the function of sealing the receiving portion (124). Specifically, the sealing portion can seal the receiving portion (124) while being formed on the terrace portion (150) formed along the perimeter of the receiving portion (124). The temperature for sealing the sealing portion (151) may be 180°C to 250°C, specifically 200°C to 250°C, and more specifically 211°C to 240°C. When the sealing temperature satisfies the above numerical range, the pouch-type battery case (110) can secure sufficient sealing strength through thermal bonding. Gas exhaust port According to the first embodiment, the pouch-shaped battery case (110) includes at least one through hole (220) formed in the cup portion or terrace portion and a gas-permeable film (210) covering the through hole (220), and is characterized in that an anti-venting index (AVI) defined by Equation 1 below is 3.0 or less, and the gas-permeable film (210) is sealed to the battery case (110) to form a sealing area (230) at the periphery of the through hole (220). [Formula 1] AVI = [A h xr h ] / [W s x C h ] In the above equation 1, A h is the total cross-sectional area of ​​the above through hole (mm 2 ) is a unitless number, and r h is a unit of the average radius (mm) of the above through-holes, and W s is a unitless number of the average width (mm) of the above sealing area, and C h is a unitless number of the total circumference (mm) of the above through hole. The above anti-venting index (AVI) is defined by taking into account the design dimensions of the through hole (220) and the gas permeable film (210) constituting the gas discharge portion (200), as described above. The above gas discharge unit (200) is important for operation at low operating pressure and for excellent gas discharge performance, but it is more important for it to be durable enough to withstand high internal pressure without venting. In order to increase the limit internal pressure that can be withstood without venting, the cross-sectional area (A) of the through hole (220) through which gas is transmitted in the gas discharge unit (200) should be increased. h ) can be designed to reduce the tension received by the internal gas by enlarging the through hole (220), but this has a limited area in which the through hole (220) can be installed in the pouch-type battery case (110), and there is also a limit to how large its size can be, and the problem of moisture infiltration from the outside or leakage of the electrolyte cannot be ignored. Total cross-sectional area (A) of the through hole (220) of an appropriate level h ), the number of through holes (220) is controlled and the average radius (r) of the through holes (220) is h ) while adjusting the appropriate width (W s ) is formed, it is possible to implement a gas discharge section (200) with excellent durability that can withstand high internal pressure under optimal conditions. That is, the total cross-sectional area (A) of the through hole (220)h ) In this case, the number of through holes (220) is increased to increase the total circumference (C h ) increases the average radius (r) of the through hole (220). h ) is reduced, the tension received by the internal gas is distributed, so that the limit pressure can be increased, and additionally, the average width (W) of the sealing area (230) s ) can increase the limit pressure further. However, the total circumference (C) of the through hole (220) h ) increases the radius (r) of the through hole (220). h ) increases the total cross-sectional area (A h ) increases together, the average width of the sealing area (W s ) increases, there is a problem that the limit pressure decreases. Average width (W) of the sealing area (230) s ) is expected to increase as the limit pressure increases, but this cannot be viewed as a simple independent relationship and the average radius (r) of the through hole (220) h ), and the total cross-sectional area (A) of the through hole (220) h ) and total circumference (C h ) can be seen to have different effects on durability that can withstand limit pressure. Considering these characteristics and relationships, the total perimeter (C) of the through hole (220) h ) for the total cross-sectional area (A) h ) ratio (A) h / C h ) and the average radius (r) of the through hole (220). h ) for the average width of the sealing area (W s ) ratio (W s / r h ) is defined as an anti-venting index, it becomes possible to implement a gas discharge section with an excellent ability to withstand limit pressure as the anti-venting index decreases. In one aspect, the anti-venting index is 3.0 or less, and specifically, may be 0.10 or more, 0.15 or more, 0.20 or more, 0.25 or more, or 0.30 or more, and further may be 2.80 or less, 2.60 or less, 2.50 or less, 2.40 or less, or 2.30 or less. When the anti-venting index is less than 0.10, the vent pressure may be high, but since gas discharge is not smooth, a swelling phenomenon may occur, or a problem of venting into the sealing portion of the pouch-type battery case (110) may occur. In addition, when the anti-venting index exceeds 3.0, there is a problem that the vent pressure is low and thus the limit pressure that can ensure the safety of the battery is not satisfied, and from this point on, the amount of moisture infiltration from the outside or the amount of electrolyte leakage may become a problem. Therefore, it is preferable that the pouch-shaped battery case (110) according to one embodiment of the present invention has a gas discharge section (210) designed so that the anti-venting index satisfies the above-described range. The total cross-sectional area (A) of the above through hole (220) h ) and total circumference (C h ) means the total sum of the cross-sectional area and circumference of the formed through holes (220), and the average radius (r) of the through holes (220) h ) is the average value of the radii of the formed through holes (220), and the average width (W) of the sealing area (230) h ) may mean a value obtained by averaging the average values ​​of the widths of the sealing areas (230) formed around each of the through holes (220). In general, the width of the sealing area (230) formed around one through hole (220) is uniform, but when it is not uniform, the average value may be utilized as described above. In one aspect, the relationship between some factors by which the anti-venting index of the gas discharge portion (200) is defined can also be defined, for example, the average radius (r) of the through hole (220) h ) for the average width (W) of the above sealing area (230)s ) ratio (W s / r h ) may be 0.45 to 3.00. Specifically, the ratio (W s / r h ) may be 0.50 or more, 0.55 or more, 0.60 or more, or 0.65 or more, and may be 2.80 or less, 2.70 or less, 2.60 or less, 2.50 or less, or 2.40 or less. When the total cross-sectional area of ​​the through hole (220) is the same and the above ratio is satisfied, the limit pressure can be increased. As another example, the ratio (Ah / Ch) of the total cross-sectional area (Ah) to the total circumference (Ch) of the through hole (220) may be 0.25 mm to 2.50 mm. Preferably, it may be 0.30 mm or more, 0.40 mm or more, 0.50 mm or more, 0.60 mm or more, 0.70 mm or more, or 0.75 mm or more, and may also be 2.40 mm or less, 2.20 mm or less, 2.00 mm or less, 1.80 mm or less, 1.50 mm or less, or 1.25 mm or less. In this case, it may mean that the through hole (220) is installed with optimal efficiency within a limited space where the through hole (220) can be installed, as long as the basic condition for increasing the limit pressure is satisfied. Area of ​​the above through hole (A H ) is 5 mm 2 25 mm inside 2 It may be, preferably, 6 mm. 2 Inside 23 mm 2 in, preferably 7 mm 2 Within 20 mm 2 If the above range is satisfied, the gas permeability index design can be facilitated with respect to the thickness of the gas permeable film (210), and it can be possible to implement a gas discharge unit (200) having excellent gas discharge performance while maintaining durability in a state where the operating pressure of the gas discharge unit (200) is lowered. Hereinafter, the gas discharge unit (200) will be described in more detail with reference to FIGS. 2 to 4. FIG. 2 is an example of a plan view of a pouch-type secondary battery showing the location where the gas discharge unit (200) is formed, FIG. 3 is a cross-sectional view of the pouch-type secondary battery at a portion where the gas discharge unit (200) is formed, and FIG. 4 is an enlarged cross-sectional view of the gas discharge unit (200) portion of FIG. 3. The above gas discharge portion (200) may be formed at one or more locations selected from the terrace portion (150) and the cup portion (122, 132) adjacent to the terrace portion (150) and not in contact with the electrode assembly inside. Here, the cup portion (122, 132) and the receiving portion (124) may not be substantially structurally distinguished, and the recessed portion formed by being molded in the pouch-type battery case (110) may be named the cup portion (122, 132), and the receiving space formed by being recessed in this way may be named the receiving portion (124). Referring to FIGS. 2 and 3, the gas discharge portion (200) may be formed in the terrace portion (150) and may be formed in the cup portion (122) or the receiving portion (124) adjacent to the terrace portion (150). In particular, the electrode assembly (160) is received and sealed inside the pouch-type battery case (110) to form the sealing portion (151). It may be preferable that the cup portion (122) be formed in a space adjacent to the terrace portion (150) and where the electrode assembly (160) and the pouch-type battery case (110) do not directly contact each other, that is, in a space where the electrode tab (170) is withdrawn from the electrode assembly (160) for electrical connection to the outside and comes into contact with the electrode lead (180). The above gas discharge unit (200) may be formed in one unit, or may be provided in two or more units, and the number of gas discharge units (200) may be designed in consideration of the characteristics of the cell applied inside, for example, whether the amount of gas generated is large or relatively small, and as long as each gas discharge unit (200) is designed to satisfy the anti-venting index, there is no particular limitation on the number, but preferably, 1 to 6 units may be formed, and more preferably, 1 to 5 units may be formed. As illustrated in FIG. 3, the gas discharge portion (200) may be arranged with a gas-permeable film (210) inside the pouch-shaped battery case (110). In this case, the portion where the gas-permeable film (210) and the pouch-shaped battery case (110) come into contact may be sealed by a method such as heat sealing, or may be sealed using an adhesive. However, sealing through heat sealing is preferable in terms of durability, may be more preferable in preventing electrolyte leakage and blocking moisture penetration, and may contribute to accurately reflecting the performance that can be implemented through the gas permeability index. Referring to FIG. 4, the gas discharge portion (200) illustrated in FIG. 3 can be seen enlarged, and the adhesive resin layer (211) of the gas permeable film (210) may be positioned to come into contact with the sealant layer (113) of the pouch-shaped battery case (110). In this case, the sealing effect through heat sealing can be maximized, which can help improve durability. According to one embodiment of the present invention, as illustrated in FIG. 4, the gas discharge unit (200) may include an adhesive resin layer (211) in contact with a pouch-shaped battery case (110) and a permeable resin layer (212) disposed on the adhesive resin layer (211). The adhesive resin layer (211) is in contact with the pouch-shaped battery case (110) and is intended to adhere the gas discharge portion (200) to the pouch-shaped battery case (110), and may include any material that is easy to adhere to the pouch-shaped battery case (110). Specifically, the adhesive resin layer (211) may include a non-fluorinated polyolefin resin, and preferably, may include a modified polyolefin resin. When the adhesive resin layer (211) includes a modified polyolefin resin, the adhesive strength between the gas discharge portion (200) and the pouch-type battery case (110) is improved, so that even when the pouch-type secondary battery is stored in a high-temperature environment, the gas discharge portion (200) can be prevented from being detached from the pouch-type battery case (110), causing the electrolyte inside the pouch to leak and moisture to permeate. The above adhesive resin layer (211) may include at least one of acid-modified polyolefin and silane-modified polyolefin. Acid-modified polyolefin refers to a polyolefin resin that has been graft-modified with an acid. For example, the acid-modified polyolefin may be a polyolefin resin in which a carboxyl group is introduced (graft-modified) by reacting an unsaturated carboxylic acid. In this case, the unsaturated carboxylic acid may include the concept of a carboxylic anhydride, and the carboxyl group may include the concept of a carboxylic anhydride group. The unsaturated carboxylic acid to be reacted with the polyolefin resin may include at least one selected from the group consisting of maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaconic acid, tetrahydrophthalic acid, aconitic acid, maleic anhydride, itaconic anhydride, glutaconic anhydride, citraconic anhydride, aconitic anhydride, norbornene dicarboxylic anhydride, and tetrahydrophthalic anhydride, but is not limited thereto. Among these, it is preferable to apply maleic anhydride to improve the adhesive strength between the gas discharge portion (200) and the electrode lead (180). The acid-modified polyolefin may include at least one selected from the group consisting of PPa (acid modified polypropylene) and PEa (acid modified polyethylene), but is not limited thereto. Silane-modified polyolefin refers to a polyolefin resin that has been graft-modified with an unsaturated silane compound. The silane-modified polyolefin may have a structure in which an unsaturated silane compound is graft-copolymerized onto a polyolefin resin as a main chain. The silane-modified polyolefin resin may include at least one selected from the group consisting of a silane-modified polypropylene resin and a silane-modified ethylene-vinyl acetate copolymer, but is not limited thereto. The adhesive resin layer (211) may be modified, and the modification treatment may include ion implantation treatment, plasma treatment, radiation treatment, heat treatment, etc., and a treatment that changes the bonding structure of the polymer layer is preferable. These modification treatments may be performed singly by one type, or may be performed in combination of two or more types. The modified adhesive resin layer (211) may include plasma-treated polypropylene (PP), but is not limited thereto. The thickness of the adhesive resin layer (211) may be 20 ㎛ to 250 ㎛, specifically 30 ㎛ to 200 ㎛, and more specifically 30 ㎛ to 150 ㎛. When the thickness of the adhesive resin layer (211) satisfies the above numerical range, the gas discharge portion (200) and the pouch-type battery case (110) can be easily fused together by melting the adhesive resin layer (211) within a set production time (tact time). In one aspect, the permeable resin layer (212) may be a layer in contact with the adhesive resin layer (211) to facilitate gas discharge. The above-mentioned permeable resin layer (212) may include a fluorine-based polyolefin resin, and preferably, may include at least one of polytetrafluoroethylene (PTFE) and polyimide (PI). The thickness of the above-mentioned permeable resin layer (212) may be 30 ㎛ to 200 ㎛, specifically 40 ㎛ to 150 ㎛, and more specifically 45 ㎛ to 100 ㎛. When the thickness of the permeable resin layer (212) satisfies the above-mentioned numerical range, the gas discharge function can be smoothly performed without detachment of the gas discharge portion (200) due to venting even when the internal pressure of the pouch-type battery case (110) increases. In one aspect, the thickness (T) of the gas permeable film (210) F) may be 80 ㎛ to 500 ㎛, specifically 80 ㎛ to 450 ㎛, 80 ㎛ to 400 ㎛, 90 ㎛ to 350 ㎛, and more preferably 100 ㎛ to 300 ㎛. When the above range is satisfied, it is easy to control the thickness ratio of the adhesive resin layer (211) and the permeable resin layer (212) constituting the gas permeable film (210), and design considering adhesive force and gas discharge performance can be facilitated. The thickness (T) of the above permeable resin layer (212) T ) The thickness (T) of the adhesive resin layer (211) A ) ratio (T A / T T ) may be 0.4 to 2.0, specifically 0.4 to 1.5, more specifically 0.4 to 1.2, and preferably 0.5 to 1.0. The ratio (T A / T T ) satisfies the above numerical range, it may be easy to implement a gas discharge unit (200) that can discharge gas while maintaining adhesiveness without permanent damage to the gas discharge unit (200) due to venting while minimizing the pressure at which the gas discharge unit (200) starts operating, and it may also be desirable to satisfy the above range when designing the gas permeability index. FIG. 5 is a plan view of a pouch-type secondary battery according to one embodiment of the present invention, such as FIG. 2, illustrating a case in which three gas discharge portions (200) are installed. Referring to FIG. 5, gas discharge portions (200) may be installed on a terrace portion (150) of a portion where an electrode lead protrudes, and an appropriate number of gas discharge portions may be installed within a range of 1 to 6 as described above. In addition, although the gas discharge portion (200) is installed only on the upper terrace portion (150) based on the drawing in FIG. 5, it may also be installed on the lower terrace portion (150), and may be installed on both the upper and lower portions. Figures 6 to 8 are enlarged plan views of area A of Figure 5, showing an enlarged view of an area where a gas discharge unit (200) is installed. Referring to Figure 6, in the case where three gas discharge units (200) are installed, the factors included in the anti-venting index can be obtained as described above. For example, the average radius (rh) of the through hole (220) in this drawing is (r h1 +r h2 +r h3 ) / 3, and the total cross-sectional area of ​​the through hole (220) (A h ) is πr h1 2 + πr h2 2 +πr h3 2 It can be obtained as , and the total circumference (C) of the through hole (220) h ) is 2πr h1 + 2πr h2 +2πr h3 can be obtained, and the average width of the sealing area (230) is (W s1 +W s2 +W s3 ) / 3, but W s1 , W s2 and W s3 Each may be an average value of the width of the sealing area sealed at the periphery of each through hole (220). In addition, as in Fig. 7, when the shape of the through hole (220) is oval rather than circular, the average radius (r h ) can be obtained as the average of the major and minor axes, so (r hl +r hs ) / 2, and in the case where the through hole (220) is a polygon as in Fig. 8, the average value of the longest and shortest straight lines among the straight lines connecting points and surfaces is the average radius (r) of the through hole (220). h ) can be used. Therefore, in the case of Fig. 8, (r hl +r hs ) / 2 as the average radius (r) h ) can be obtained. The pouch-type battery case according to the first embodiment of the present invention is provided with a gas discharge unit as described above, so that it can operate at a low operating pressure, has a satisfactory level of gas discharge performance, and can withstand high internal pressure, thereby greatly improving durability. As a result, it can contribute to an improvement in lifespan, and it has the advantage of being able to maintain the operating performance of the cell by continuously discharging gas, and it can also ensure safety by stably discharging gas while suppressing the venting phenomenon. Second embodiment A pouch-shaped battery case according to a second embodiment comprises: a cup portion having a receiving space for accommodating an electrode assembly; a terrace portion formed along a periphery of the receiving portion; and a gas discharge portion, wherein the gas discharge portion is provided at at least one position among the cup portion and the terrace portion, and each gas discharge portion comprises a gas discharge portion including at least one through hole and a gas permeable film covering the through hole; wherein the gas permeable film includes an adhesive resin layer and a permeable resin layer disposed on the adhesive resin layer, and each gas discharge portion is characterized in that a gas permeability index (GPI) expressed by the following Equation 2 is 0.05 to 0.55. [Formula 2] GPI = (A H x T A ) / (TS A x T F ) In the above equation 2, T F is a unit number of the total thickness (㎛) of the above gas permeable film, and T A is a unit number of the thickness (㎛) of the adhesive resin layer, and TS A is the tensile strength of the adhesive resin layer (kgf / mm) 2 ) is a unitless number, and A H is the area of ​​the through hole (mm) 2 ) is a unitless number. According to the second embodiment of the present invention, a gas discharge portion sealed with a gas-permeable film can be provided so that gas can be discharged through a through hole formed in a pouch-shaped battery case, but the inflow and outflow of liquid can be effectively blocked. When gas is discharged by permeating through a gas-permeable film covering a penetration hole in a gas discharge portion, the area of ​​the gas-permeable portion and the thickness of the gas-permeable film, and especially, the dimensions of the proportion of the adhesive resin layer in the gas-permeable film affect the gas discharge performance, the inflow and outflow of liquid (moisture and electrolyte), and the tensile strength of the gas-permeable film affects the adhesive strength and gas permeability, and thus the gas permeability index can be defined using these design dimensions as factors. As described above, the above gas permeability index can be defined by taking into account the design dimensions of the through hole (220) and the gas permeable film (210) constituting the gas discharge portion (200). The gas discharge portion (200) has a better gas discharge performance as the area of ​​the through hole increases, but the direction in which the area of ​​the through hole (220) increases has a negative effect on the performance of preventing moisture penetration and electrolyte leakage. Therefore, if the area of ​​the through hole (220) is narrowed for the purpose of preventing moisture penetration and electrolyte leakage, the gas discharge performance deteriorates, and the tension applied to the gas-permeable film (210) during gas discharge may increase, and thus the adhesive strength with the pouch-type battery case (110) may become a problem. Therefore, the tensile strength of the adhesive resin layer (211) must also be considered so that the gas-permeable film (210) can maintain the adhesive strength while withstanding the tension generated by gas discharge. In addition, the thinner the gas permeable film (210), the better the gas discharge performance may be; however, as the film becomes thinner, problems may arise in preventing moisture penetration and electrolyte leakage due to adhesive strength issues, and even when designed thin, the adhesive strength and gas discharge performance may be affected depending on the thickness design of each of the adhesive resin layer (211) and the permeable resin layer (212). Considering these characteristics, the thickness (T) of the entire gas permeable film (210) F ) The thickness (T) of the adhesive resin layer (211) A ) ratio (T A / T F ) and the tensile strength (TS) of the adhesive resin layer (211) A ) area of ​​the through hole (220) (A) H ) by reflecting the ratio of the gas permeability index, the present invention minimizes electrolyte leakage from the inside to the outside of a pouch-type battery case by setting an appropriate value of the gas permeability index, and enables the design of a gas discharge section with excellent discharge performance during operation while minimizing moisture infiltrating from the outside. The above gas permeability index is from 0.05 to 0.55, and specifically, may be 0.08 or more, 0.10 or more, 0.15 or more, or 0.17 or more, and also may be 0.53 or less, 0.50 or less, or 0.48 or less. When the above gas permeability index is less than 0.05, the area of ​​the penetration hole (220) is small compared to the tensile strength of the adhesive resin layer (211), so that the gas discharge performance may be poor, and as a result, the swelling phenomenon may not be prevented as the internal pressure increases, and the thickness ratio of the adhesive resin layer (212) may be relatively too small, so that durability may be problematic, and a venting problem may occur as the internal pressure increases. When the above gas permeability index exceeds 0.55, the tension applied to the gas permeable film (210) decreases as the area of ​​the penetration hole (220) increases relative to the tensile strength of the adhesive resin layer (211), so durability can be secured. However, since the thickness of the permeable resin layer (212) becomes relatively thin, there is a concern that moisture infiltration from the outside may become a serious problem, and along with this, a phenomenon of electrolyte leakage may occur. It is preferable that the pouch-shaped battery case (110) according to the second embodiment has a gas discharge section (200) designed so that the gas permeability index satisfies the above-mentioned range. The pouch-type battery case according to the second embodiment of the present invention can significantly improve the performance of preventing electrolyte leakage and moisture infiltration by having the gas discharge portion as described above, while maintaining a satisfactory level of gas discharge performance. As a result, there is no problem of corrosion due to generated gas or corrosion due to moisture infiltration or electrolyte leakage, so that it can contribute to improving the lifespan by increasing durability, and the driving performance of the cell can be maintained by continuous gas discharge, and the risk of explosion due to swelling is also reduced, so that safety can be secured. In addition, the technical configuration and description thereof regarding the cup portion, terrace portion, and gas discharge portion constituting the pouch-type battery case, and the technical configuration and description thereof regarding the pouch film laminate which is the material of the pouch-type battery case, can be applied in the same manner as the first embodiment, unless they conflict with the second embodiment. Third embodiment A pouch-shaped battery case according to a third embodiment comprises: a cup portion having a receiving space for accommodating an electrode assembly; a terrace portion formed along a periphery of the receiving portion; and one or more gas discharge portions, wherein the gas discharge portions are formed at one or more positions among the cup portion and the terrace portions, each of the gas discharge portions comprises one or more through holes and a gas-permeable film covering the through holes, the gas-permeable film comprises an adhesive resin layer and a permeable resin layer disposed on the adhesive resin layer, the gas-permeable film is sealed to the battery case to form a sealing region around the through holes, and each of the gas discharge portions has a Water Blocking Index (WBI) expressed by Equation 3 below of 2.0 to 10.5. [Formula 3] WBI = (A S x T F x T T ) / (A H x T A x 100) In the above equation 3, A S is the area of ​​the sealing area (mm) 2 ) is a unitless number, and T F is a unit number of the total thickness (㎛) of the above gas permeable film, and T A is a unit number of the thickness (㎛) of the adhesive resin layer, and T T is a unit number of the thickness (㎛) of the permeable resin layer, and A H is the area of ​​the through hole (mm) 2) is a unitless number. According to the third embodiment of the present invention, a gas discharge portion sealed with a gas-permeable film can be provided so that gas can be discharged through a through hole formed in a pouch-shaped battery case, but the inflow and outflow of liquid can be effectively blocked. When gas is discharged by permeating through the gas-permeable film via the through-hole at the gas discharge portion, the area of ​​the gas-permeable portion and the total thickness of the gas-permeable film, as well as the ratio of the thickness of the adhesive resin layer to the thickness of the permeable resin layer in the gas-permeable film, affect the gas discharge performance and the inflow and outflow of liquid (moisture and electrolyte), and the moisture blocking index can be defined using these design dimensions as factors. The above moisture blocking index is defined by taking into account the design dimensions of the through hole (220) and the gas permeable film (210) constituting the gas discharge portion as factors, as described above. The gas discharge portion (200) above has excellent gas discharge performance as the area of ​​the through hole increases, but the direction in which the area of ​​the through hole (220) increases has a negative effect on the moisture penetration and electrolyte leakage prevention performance, and in terms of the durability of the through hole, the bonding area between the gas permeable film (210) and the pouch-shaped case (110), i.e., the sealing area, cannot be overlooked, so it is necessary to consider the area in which the gas permeable film (210) is in contact with the pouch-shaped battery case (110). In addition, the thinner the gas permeable film (210), the better the gas discharge performance, but as it becomes thinner, problems arise in the moisture penetration and electrolyte leakage prevention performance due to adhesive strength issues, and even when designed thinly, the adhesive strength, gas discharge performance, and moisture penetration and electrolyte leakage prevention performance may be affected depending on the thickness design of each of the adhesive resin layer (211) and the permeable resin layer (212). Considering these characteristics, the thickness (T) of the permeable resin layer (212) within the entire gas permeable film (210) T) The thickness (T) of the adhesive resin layer (211) A ) ratio (T A / T T ) and the area (A) of the through hole (220) H ) The area (A) of the sealing region where the gas permeable film (210) is in contact with the pouch-shaped battery case (110) S ) is reflected as a ratio, and the total thickness (T) of the gas permeable film (210) is F ), the present invention minimizes electrolyte leakage from the inside to the outside of a pouch-type battery case while maintaining gas discharge performance by setting an appropriate value of a moisture blocking index, and enables the design of a gas discharge section to minimize moisture infiltrating from the outside. The moisture barrier index is from 2.0 to 10.5, and may be, for example, 2.3 or more, 2.5 or more, or 3.0 or more, and may also be 10.0 or less, 9.0 or less, 8.0 or less, 7.0 or less, or 6.0 or less. If the above moisture blocking index is less than 2.0, the bonding area (area of ​​the sealing area) between the gas permeable film (210) and the pouch-type battery case (110) may be small compared to the area of ​​the through hole (220), and thus problems such as moisture penetration or electrolyte leakage may occur, and it cannot be ruled out that the durability itself may be a problem. If the above moisture blocking index exceeds 10.5, problems may arise with gas discharge performance, such as the gas discharge speed being too slow to prevent swelling, and the adhesive resin layer being relatively thin may cause the seal to be released as the internal pressure increases, ultimately causing venting to occur when the adhesive strength limit is exceeded. It is preferable that the pouch-shaped battery case (110) according to the third embodiment of the present invention has a gas discharge section (200) designed so that the moisture blocking index satisfies the above-mentioned range. The pouch-type battery case according to the third embodiment of the present invention can significantly improve the performance of preventing electrolyte leakage and moisture infiltration by having the gas discharge portion as described above, so that the gas discharge performance is at a satisfactory level. As a result, there is no problem of corrosion due to generated gas or corrosion due to moisture infiltration or electrolyte leakage, so that it can contribute to the improvement of durability and lifespan, and the driving performance of the cell can be maintained through continuous gas discharge, and the risk of explosion due to swelling is also reduced, so that safety can be secured. In addition, the technical configuration and description thereof regarding the cup portion, terrace portion, and gas discharge portion constituting the pouch-type battery case, and the technical configuration and description thereof regarding the pouch film laminate which is the material of the pouch-type battery case, can be applied in the same manner as the first embodiment, unless they conflict with the third embodiment. Pouch-type secondary battery In another aspect, a pouch-type secondary battery (100) is provided, which includes: an electrode assembly (160); a pouch-type battery case (110) as described above; an electrode lead (180) connected to the electrode assembly (160) and protruding to the outside of the pouch-type case (110) via the terrace portion (150); and a lead film (190) disposed between the electrode lead (180) and the pouch-type case (110) on the terrace portion (150), wherein a portion of the terrace portion (150) is sealed along the periphery of the cup portion (122, 132) to form a sealing portion (151). In the case of the pouch-type battery case (110) and the gas discharge unit (200) provided in the pouch-type battery case (110), the technical configurations and features corresponding to the first to third embodiments can be applied to the pouch-type secondary battery, and a detailed description thereof is omitted because it overlaps with the above-described contents. Hereinafter, other components included in the pouch-type secondary battery (100) will be described. Electrode assembly In one aspect, the electrode assembly (160) may be housed in the receiving portion (124) of the pouch-type battery case (110) and sealed by a sealing portion (151) formed by thermal fusion of the terrace portion (150) after electrolyte injection. The electrode assembly (160) may be formed by sequentially stacking an anode, a separator, and a cathode. Specifically, the electrode assembly (160) may include two types of electrodes, an anode and a cathode, and a separator interposed between the electrodes to mutually insulate the electrodes. The positive and negative electrodes 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 be formed by stirring a granular active material, an auxiliary conductor, a binder, and a conductive agent while a solvent is added. The solvent may be removed in a subsequent process. A slurry containing an electrode active material and a binder and / or a conductive material is applied to a positive electrode current collector and a negative electrode current collector to manufacture a positive electrode and a negative electrode, and the positive electrode and negative electrode are laminated on both sides of a separator, thereby manufacturing an electrode assembly (160) in a predetermined shape. The types of the electrode assembly (160) may include, but are not limited to, a stack type, a jelly roll type, a stack and folding type, etc. The electrode assembly (160) may include an electrode tab (170). Referring to FIG. 1, the electrode tabs (170) are respectively connected to the positive and negative electrodes of the electrode assembly (160), and protrude outwardly from the electrode assembly (160) to serve as a path through which electrons can move between the inside and the outside of the electrode assembly (160). The electrode current collector included in the electrode assembly (160) may be composed of a portion where an electrode active material is applied and a terminal portion where the electrode active material is not applied, i.e., a non-coated portion. The electrode tabs (170) may be formed by cutting the non-coated portion or by connecting a separate conductive member to the non-coated portion by ultrasonic welding, etc. As illustrated in FIG. 1, the electrode tabs (170) may protrude in different directions from each other in the electrode assembly (160), but are not limited thereto, and may be formed to protrude in various directions, such as protruding side by side in the same direction from one side. Electrode Leads In one aspect, the electrode lead (180) can supply electricity to the outside of the secondary battery (100). The electrode lead (180) can be connected to the electrode tab (170) of the electrode assembly (160) by spot welding or the like. Referring to FIGS. 1 and 3, the electrode lead (180) may be connected to the electrode assembly (160) and may protrude to the outside of the pouch-shaped battery case (110) via the terrace portion (150). Specifically, one end of the electrode lead (180) may be connected to the electrode assembly (160), particularly the electrode tab (170), and the other end of the electrode lead (180) may protrude to the outside of the pouch-shaped battery case (110) via the terrace portion (150). The electrode lead (180) may include a positive lead (182) having one end connected to the positive tab (172) and extending in the protruding direction of the positive tab (172), and a negative lead (184) having one end connected to the negative tab (174) and extending in the protruding direction of the negative tab (174). Both the positive lead (182) and the negative lead (184) may have other ends protruding outward from the battery case (110). Accordingly, electricity generated inside the electrode assembly (160) may be supplied to the outside. In addition, since the positive tab (172) and the negative tab (174) are formed to protrude in various directions, the positive lead (182) and the negative lead (184) may also extend in various directions, respectively. The positive lead (182) and the negative lead (184) may be made of different materials. That is, the positive electrode lead (182) may be made of the same aluminum (Al) material as the positive electrode collector, and the negative electrode lead (184) may be made of the same copper (Cu) material as the negative electrode collector or a copper material coated with nickel (Ni). A portion of the electrode lead (180) protruding outside the battery case (110) may be a terminal portion and may be electrically connected to an external terminal. One side of the electrode lead (180) that comes into direct contact with the lead film (190) and / or the gas discharge portion (200) is made of chromium (Cr), nickel (Ni), or aluminum oxide (Al). 2 O 3 ), zirconium (Zr)-based anhydride salt and titanium (Ti)-based anhydride salt may be coated with at least one selected from the group consisting of anhydride salt. In this case, corrosion resistance against the electrolyte and adhesion to the lead film (190) and / or the gas discharge portion (200) may be secured. (5) Lead film In one aspect, the lead film (190) prevents electricity generated from the electrode assembly (160) from flowing to the battery case (110) through the electrode lead (180) and maintains the sealing of the battery case (110). To this end, the lead film (190) may be formed of a non-conductive material that does not conduct electricity well. In general, the lead film (190) is often made of an insulating tape that is easy to attach to the electrode lead (180) and / or the gas discharge portion (200) and has a relatively thin thickness, but is not limited thereto, and any material capable of insulating the electrode lead (180) may be used. The lead film (190) may be arranged to wrap around the outer surface of the electrode lead (180). The lead film (190) may be positioned limited to the terrace portion (150) where the sealing portion (151) where the first case (120) and the second case (130) of the pouch-type battery case (110) are thermally fused is positioned, and the electrode lead (180) may be adhered to the battery case (110). The lead film (190) may be placed between the electrode lead (180) and the pouch-shaped battery case (110). For example, as shown in FIG. 3, the lower case (110), the lead film (190), the electrode lead (180), the lead film (190), and the upper case (110) may be placed in a sequentially stacked state in the terrace portion (150) area. The lead film (190) may include one or more layers. Specifically, the lead film (190) may include a sequentially laminated metal adhesive layer, a core layer, and a pouch adhesive layer. The metal adhesive layer is in direct contact with the electrode lead (180) and may be used to adhere the lead film (190) to the electrode lead (180). The metal adhesive layer may include any material that is easy to adhere to the electrode lead (180). Specifically, the metal adhesive layer may include an acid-modified polyolefin. For example, the metal adhesive layer may include at least one of PPa (acid modified polypropylene), PEa (acid modified polyethylene), and plasma-treated PP (plasma-treated polypropylene), but is not limited thereto. The thickness may be 50 ㎛ to 80 ㎛, specifically 50 ㎛ to 75 ㎛, and more specifically 60 ㎛ to 75 ㎛. When the thickness of the metal adhesive layer satisfies the above numerical range, there is an effect of preventing a through-hole and a leak at an edge portion when fusion is performed between the electrode lead and the lead film. The core layer may be a layer located at the center of the lead film (190). The core layer may include, but is not limited to, additives such as polypropylene, polyolefin elastomer (POE), and / or a colorant. Among them, the polymer included in the core layer may be a homopolymer. When the core layer includes a homopolymer, the melting point of the core layer can be controlled within the above numerical range, and deformation due to heat can be minimized, which is advantageous in terms of securing insulation. The thickness of the core layer may be 40 ㎛ to 70 ㎛, specifically 50 ㎛ to 70 ㎛, and more specifically 60 ㎛ to 70 ㎛. When the thickness of the core layer satisfies the above numerical range, deformation due to heat applied during fusion and sealing is prevented, thereby providing a robust design effect in terms of securing insulation. The pouch adhesive layer may be a layer that directly contacts the battery case (110), specifically, the sealant layer of the pouch film laminate. The pouch adhesive layer may include, but is not limited to, polypropylene and polyolefin elastomer (POE). Among them, the polymer included in the pouch adhesive layer may be a copolymer. The melting point of the pouch adhesive layer including the copolymer in the pouch adhesive layer can be controlled within the above numerical range and has a similar melting point to the polymer in the sealant layer of the pouch film laminate, which is advantageous in securing the sealing processability. The thickness of the pouch adhesive layer may be 40 ㎛ to 100 ㎛, specifically, 40 ㎛ to 80 ㎛, and more specifically, 40 ㎛ to 60 ㎛. When the thickness of the pouch adhesive layer satisfies the above numerical range, there is an effect of securing a polymer (e.g., polypropylene) residual rate sufficient to secure strength when sealing between the electrode lead and the pouch film laminate. Electrolyte The above pouch-type secondary battery (100) may further include an electrolyte (not shown) that is poured inside the pouch-type battery case (110). The electrolyte is for moving lithium ions generated by an electrochemical reaction of an electrode during charging / discharging of the secondary battery (100), and may include a non-aqueous organic electrolyte that is a mixture of a lithium salt and an organic solvent, or a polymer using a polymer electrolyte. Furthermore, the electrolyte may include a solid electrolyte of a sulfide type, an oxide type, or a polymer type, and such a solid electrolyte may have flexibility that is easily deformed by an external force. Hereinafter, the present invention will be described in more detail through specific examples. However, the following examples are merely examples to help understand the present invention and do not limit the scope of the present invention. It will be obvious to those skilled in the art that various changes and modifications are possible within the scope and technical idea of ​​the present description, and it is natural that such changes and modifications fall within the scope of the appended patent claims. Examples and Comparative Examples Pouch-type secondary battery with pouch-type battery case according to first embodiment Examples 1a to 9a and Comparative Examples 1a to 7a (1) Manufacturing of pouch-type battery case A pouch film laminate having a structure of polyethylene terephthalate / nylon / aluminum alloy film / polypropylene film was manufactured by laminating a polyethylene terephthalate (PET) film having a width of 266 mm, a height of 260 m, and a thickness of 12 μm and a nylon film having a width of 266 mm, a height of 260 m, and a thickness of 25 μm on one side of an aluminum alloy film having a width of 266 mm, a height of 260 m, and a thickness of 60 μm, and laminating a polypropylene film having a width of 266 mm, a height of 260 m, and a thickness of 80 μm on the other side. Here, the polyethylene terephthalate film and the nylon film are substrate layers, the aluminum alloy film is a gas barrier layer, and the polypropylene film is a sealant layer. The above pouch film laminate was formed to manufacture a pouch-shaped battery case including a receiving portion and a terrace portion, and a through hole was formed on the receiving portion (cup portion) adjacent to the terrace portion as shown in FIGS. 2 and 3, and a gas-permeable film was sealed on the inside of the pouch-shaped battery case as shown in FIGS. 4 to 6 to form a gas discharge portion. Here, the gas discharge portion was designed as shown in Table 1 below, and 100 ㎛ thick polytetrafluoroethylene (PTFE) was applied as the permeable resin layer for the gas permeable film, and 100 ㎛ thick acid-modified polypropylene (PPa) was applied as the adhesive resin layer. (2) Manufacturing of pouch-type secondary batteries An electrode assembly was manufactured by stacking and laminating the cathode and anode and the porous polyethylene separator. Thereafter, an electrode lead was bonded to the electrode assembly. LiPF in solvent (EC:EMC:DMC = 3:3:4 volume ratio) 6 An electrolyte was prepared by dissolving the electrolyte to a concentration of 1.0 M. The electrode assembly was placed in the pouch-type battery case with the tip of the electrode lead extended to the outside, and about 20 g of the electrolyte was injected. Next, a 200 ㎛ thick lead film was laminated on the lower surface of the electrode lead and the upper surface of the gas discharge portion, respectively. The lead film includes a 75 ㎛ thick metal adhesive layer containing copolymer polypropylene and acid-modified polypropylene, a 65 ㎛ thick core layer containing homopolymer polypropylene, and a 60 ㎛ thick pouch adhesive layer containing copolymer polypropylene. Thereafter, the sealing part of the pouch-type battery case was sealed for 2 seconds under the conditions of a seal bar area of ​​200 mm × 10 mm, 212°C, and 0.27 MPa, and then left at 60°C for 4 hours to manufacture a pouch-type secondary battery. Number of holesAverage radius of holes (mm)Total cross-sectional area of ​​holes (mm) 2) Total circumference of the hole (mm) Average width of the sealing area (mm) (Total cross-sectional area) / (Total circumference) (Average width of the sealing area) / (Average radius of the through hole) AVI Example 1a12.56.2552.51.251.001.25 Example 2a13.0962.01.500.672.25 Example 3a22.512.5102.51.251.001.25 Example 4a33.027182.01.500.672.25 Example 5a41.59123.50.752.330.32 Example 6a41.59121.00.750.671.13 Example 7a42.525202.51.251.001.25Example 8a52.020203.01.001.500.67Example 9a52.020201.01.000.502.00Comparative Example 1a12.56.2551.01.250.403.13Comparative Example 2a13.0961.01.500.334.50Comparative Example 3a22.512.5101.01.250.403.13Comparative Example 4a24.032161.02.000.258.00Comparative Example 5a33.027181.01.500.334.50Comparative Example 6a42.525201.01.250.403.13Comparison Example 7a44.064321.02.000.258.00 * π is omitted Experimental Example 1a: Evaluation of the Gas Emission Section In order to evaluate the performance of the above gas discharge portion, the vent pressure was measured. The vent pressure (bar) was measured by injecting air into the pouch-type secondary battery using pressure equipment from ITS Corporation to increase the pressure inside the pouch to 2.0 bar, and then increasing the pressure by 0.5 bar at a time, and measuring the pressure at the point when the gas discharge portion was damaged and the internal gas was completely vented. The results are shown in Table 2 below. AVI vent pressure (bar) Example 1a1.256.50 Example 2a2.255.00 Example 3a1.255.50 Example 4a2.255.00 Example 5a0.327.25 Example 6a1.136.50 Example 7a1.256.25 Example 8a0.677.00 Example 9a2.005.25 Comparative Example 1a3.134.75 Comparative Example 2a4.504.50 Comparative Example 3a3.134.50 Comparative Example 4a8.002.50 Comparative Example 5a4.503.00 Comparative Example 6a3.134.00 Comparative Example 7a8.002.00 Referring to Table 2 above, in the case of Examples 1a to 9a, the AVI value was satisfied by controlling the number and size of holes and the sealing width, etc. through precise design of the gas discharge portion, and accordingly, the vent pressure was high as 5.0 bar or more. However, in the case of Comparative Examples 1a to 7a, although the design dimensions were similar to those of the Examples, the AVI value was not satisfied due to failure to control precisely, and accordingly, the vent pressure was found to be considerably low. Through this, it was confirmed that when a gas discharge part is designed and applied according to AVI, such as examples with high vent pressure, the durability of the gas discharge part is excellent, so that even if a large amount of gas is generated from the battery, the gas is discharged smoothly, and since the vent pressure is high, a lithium secondary battery with excellent durability and long life can be provided. Pouch-type secondary battery with pouch-type battery case according to the second embodiment Examples 1b to 8b, Comparative Examples 1b to 4b (1) Manufacturing of pouch-type battery case A pouch-shaped battery case including a receiving portion and a terrace portion was manufactured by molding a pouch film laminate manufactured in the same manner as in Example 1a, and a through hole was formed on the receiving portion (cup portion) adjacent to the terrace portion as shown in Fig. 2, and a gas-permeable film was thermally bonded inside the pouch-shaped battery case to form a gas discharge portion. Here, the gas discharge portion was designed as shown in Table 3 below. In Table 3 below, PP means polypropylene, PE means polyethylene, and PPa means acid-modified polypropylene. (2) Manufacturing of pouch-type secondary batteries A pouch-type secondary battery was manufactured by applying the same method as in Example 1a, but using the pouch-type battery case manufactured in (1) of Example 1b. Adhesive layer thickness, T A (㎛) Adhesive layer tensile strength, TS A (kgf / mm 2 ) Adhesive layer type, permeable layer thickness, T T (㎛) Type of permeable layer Penetration hole area, A H (mm 2 )GPIExample 1b10020.3PPa100PTFE7.070.17Example 2b10020.3PPa100PTFE12.570.31Example 3b10020.3PPa100PTFE19.630.48Example 4b6020.3PP100PTFE7.070.13Example 5b6020.3PP100PTFE12.570.23Example 6b6020.3PP100PTFE19.630.36Example 7b10020.3PPa80PTFE19.630.54Example 8b10011.9PE100PTFE12.570.52Comparative Example 1b6011.9PPa40PTFE19.630.99Comparative Example 2b6012.1PPa60PTFE19.630.82Comparative Example 3b405.6PE100PTFE12.570.64Comparative Example 4b15046.3PP100PTFE3.140.04 * Adhesive layer: adhesive resin layer, Transmittance layer: transmittance resin layer Experimental Example 1b: Evaluation of the Gas Emission Section The properties of the gas permeable film were measured and the performance was evaluated by the following method for the following items. 1) Gas emission rate (cc / day): CO emission rate inside a pouch-type secondary battery using pressure equipment from ITS Co., Ltd. 2After increasing the pressure inside the pouch to 1.5 atm by injecting the gas, the amount of gas discharged for 24 hours was measured, and the results are shown in Table 4 below. 2) HF concentration (ppm): The degree of moisture penetration was evaluated by measuring the concentration of HF (weight ppm) in the electrolyte by opening the pouch-type secondary battery after leaving it under conditions of 60℃ and 90% relative humidity for 16 weeks, and the results are shown in Table 4 below. GPIHF Concentration (ppm) Emission Rate (cc / day) Example 1b 0.177 10.64.6 Example 2b 0.315 44.84.9 Example 3b 0.486 17.87.0 Example 4b 0.134 45.05.1 Example 5b 0.234 94.456.6 Example 6b 0.365 49.48.0 Example 7b 0.547 13.17.7 Example 8b 0.535 48.05.3 Comparative Example 1b 0.98 1110.412.0 Comparative Example 2b 0.609 53.110.9 Comparative Example 3b 0.649 63.28.6 Comparative Example 4b 0.044 14.33.3 Referring to Table 4 above, in the case of Examples 1b to 8b having a gas permeability index of 0.05 to 0.55, it was confirmed that the discharge speed was maintained at an appropriate speed to prevent swelling of the pouch-type secondary battery and venting, while having excellent moisture penetration prevention capability, making it possible to achieve an HF concentration of 800 ppm or less. However, in the case of Comparative Examples 1b to 3b, the gas permeability index exceeds 0.55, which indicates that the moisture infiltration amount is large and the HF concentration exceeds 900 ppm. In addition, even if the gas discharge rate is secured, it can be seen that moisture is also entering and exiting, confirming that long-term stability is poor and commercialization is difficult. Furthermore, in Comparative Example 4b, the gas permeability index is less than 0.05, so even if a certain level of performance is secured for moisture infiltration, the gas discharge rate is too poor, and it can be expected that it is difficult to prevent swelling or venting of the battery. Through this, it can be confirmed that, when designing a gas discharge unit of a pouch-type secondary battery according to one embodiment of the present invention, by controlling factors so that the gas permeability index satisfies a range of 0.5 to 0.55, a gas discharge unit with excellent gas discharge performance can be implemented while securing a certain level of performance against moisture infiltration. Pouch-type secondary battery with pouch-type battery case according to the third embodiment Examples 1c to 9c, Comparative Examples 1c to 3c (1) Manufacturing of pouch-type battery case A pouch-shaped battery case including a receiving portion and a terrace portion was manufactured by molding a pouch film laminate manufactured in the same manner as in Example 1a, and a through hole was formed on the receiving portion (cup portion) adjacent to the terrace portion as shown in Fig. 2, and a gas-permeable film was thermally bonded inside the pouch-shaped battery case to form a gas discharge portion. Here, the gas discharge portion was designed as shown in Table 5 below. In Table 5 below, PP means polypropylene, PE means polyethylene, and PPa means acid-modified polypropylene. (2) Manufacturing of pouch-type secondary batteries A pouch-type secondary battery was manufactured by applying the same method as in Example 1a, except that the pouch-type battery case was manufactured in (1) of Example 1c. Adhesive layer thickness, T A (㎛) Adhesive layer type Transmittance layer thickness, T T (㎛) Type of permeable layer Penetration hole area, A H (mm 2 ) Area of ​​the sealing area, A S (mm 2)WBIExample 1c100PE100PTFE7.0735.39.99Example 2c100PE100PTFE7.0718.85.32Example 3c100PP60PTFE7.0735.34.79Example 4c100PP100PTFE7.0712.63.57Example 5c100PPa100PTFE19.6335.33.60Example 6c100PPa200PTFE19.6318.85.74Example 7c100PPa60PTFE7.0718.82.55Example 8c80PPa100PTFE12.5718.83.37Example 9c80PPa100PTFE12.5735.36.32Comparative Example 1c50PPa60PTFE19.6318.81.26Comparative Example 2c20PPa60PTFE7.0735.311.90Comparative Example 3c100PPa200PTFE7.0718.815.95 * Adhesive layer: adhesive resin layer, Transmittance layer: transmittance resin layer Experimental Example 1c: Evaluation of the Gas Emission Section The properties of the gas permeable film were measured and the performance was evaluated by the following method for the following items. 1) Gas emission rate (cc / day): CO emission rate inside a pouch-type secondary battery using pressure equipment from ITS Co. 2 After increasing the pressure inside the pouch to 1.5 atm by injecting the gas, the amount of gas discharged for 24 hours was measured, and the results are shown in Table 4 below. 2) HF concentration (ppm): The degree of moisture penetration was evaluated by measuring the concentration of HF (weight ppm) in the electrolyte by opening the pouch-type secondary battery after leaving it under conditions of 60℃ and 90% relative humidity for 16 weeks, and the results are shown in Table 6 below. WBI emission rate (cc / day) HF concentration (ppm) Example 1c 9.99 4.4426.2 Example 2c 5.325.6496.3 Example 3c 4.798.5399.4 Example 4c 3.576.4293.7 Example 5c 3.607.2617.8 Example 6c 5.744.8308.9 Example 7c 2.559.6821.6 Example 8c 3.377.9679.6 Example 9c 6.328.4702.9 Comparative Example 1c 1.2613.4986.0 Comparative Example 2c 11.99 16.11423.1 Comparative Example 3c 15.963.1222.4 According to Table 6 above, the moisture barrier index (WBI) can be defined according to the thickness ratio of the adhesive resin layer and the permeable resin layer and the ratio of the area of ​​the penetration hole and the area of ​​the sealing area, and it can be confirmed that the moisture barrier effect is also reflected accordingly. In the case of Examples 1c to 9c, it can be seen that the moisture barrier performance is excellent while having a satisfactory level of gas discharge performance since the WBI satisfies the range of 2.0 to 10.5. However, in cases where the WBI is less than 2.0, such as in Comparative Example 1c, the thickness of the permeable resin layer is thin compared to the thickness of the adhesive resin layer, the thickness of the entire gas-permeable film is thin, and the appropriate design of the ratio of the area of ​​the sealing area to the area of ​​the through hole fails, so that the gas discharge performance and moisture penetration prevention performance are poor. In addition, in the cases of Comparative Examples 2c and 3c, the WBI value exceeds 10.5, and in Comparative Example 2c, the hole area was reduced and the sealing was widened in order to solve the problem of Comparative Example 1c, but this was also excessive to the extent that the WBI value could not be controlled, so that the moisture penetration problem was not solved despite the hole being narrow. In cases where the WBI value is not satisfied, it can be confirmed through Comparative Example 3c that the trade-off relationship between the decrease in discharge speed due to the increase in film thickness and the moisture penetration prevention performance is not resolved. [Explanation of symbols] 100: Pouch-type secondary battery 110: Pouch-type battery case 111: Base layer 112: Gas barrier layer 113: Sealant layer 120: Case 1 122: Cup part 124: Reception area 130: Case 2 132: Cup part 140: Bridge section 150: Terrace 151: Sealing part 160: Electrode assembly 170: Electrode tab 172: Bipolar tab 174: Negative tab 180: Electrode Lead 182: Bipolar Lead 184: Negative lead 190: Lead Film 200: Gas exhaust 210: Gas permeable film 211: Adhesive resin layer 212: Permeable resin layer 220: Through hole 230: Ceiling area

Claims

1. A pouch-shaped battery case including a cup portion having a receiving space for storing an electrode assembly; a terrace portion formed along the periphery of the receiving portion; and a gas discharge portion; The gas discharge portion is provided at one or more locations among the cup portion and the terrace portion, and each gas discharge portion includes one or more through holes and a gas-permeable film covering the through holes. The above gas permeable film is sealed to the battery case to form a sealing area around the through hole, The above gas discharge unit is a pouch-type battery case having an anti-venting index (AVI) of 3.0 or less, as defined by the following equation 1: [Formula 1] AVI = [A h x r h ] / [W s x C h ] In the above equation 1, A h is the total cross-sectional area of ​​the above through hole (mm 2 ) is a unitless number, and r h is a unit of the average radius (mm) of the above through-holes, and W s is a unitless number of the average width (mm) of the above sealing area, and C h is a unitless number of the total circumference (mm) of the above through hole.

2. In paragraph 1, A pouch-type battery case having an anti-venting index (AVI) of 0.10 to 2.

50.

3. In paragraph 1, A pouch-shaped battery case, wherein the gas discharge portion has a ratio of the average width of the sealing area to the average radius of the through hole of 0.45 to 3.

00.

4. In paragraph 1, A pouch-shaped battery case, wherein the gas discharge portion has a ratio of the total cross-sectional area of ​​the through hole to the total circumference of the through hole of 0.25 mm to 2.50 mm.

5. In paragraph 1, A pouch-shaped battery case, wherein the gas discharge portion is formed at one or more locations selected from among a terrace portion and a cup portion adjacent to the terrace portion and not in contact with the electrode assembly inside.

6. In paragraph 1, A pouch-shaped battery case having 1 to 6 through holes.

7. In paragraph 1, Total cross-sectional area of ​​the above through hole (A H ) is 5 mm 2 25 mm inside 2 A pouch-type battery case.

8. In paragraph 1, A pouch-shaped battery case, wherein the thickness of the gas-permeable film is 80 ㎛ to 500 ㎛.

9. In paragraph 1, A pouch-shaped battery case, wherein the gas-permeable film is placed inside the battery case.

10. In paragraph 1, A pouch-shaped battery case, wherein the gas-permeable film includes an adhesive resin layer in contact with the battery case and a permeable resin layer disposed on the adhesive resin layer.

11. In paragraph 10, A pouch-shaped battery case, wherein the adhesive resin layer comprises a non-fluorinated polyolefin resin.

12. In paragraph 10, A pouch-shaped battery case, wherein the above-mentioned permeable resin layer contains a fluorinated polyolefin resin.

13. In paragraph 10, The thickness of the above permeable resin layer (T T ) The thickness (T) of the adhesive resin layer A ) ratio (T A / T T ) is a pouch-type battery case with a value of 0.4 to 2.

0.

14. In paragraph 1, The above pouch-shaped battery case is a pouch-shaped battery case having a structure in which a substrate layer, a gas barrier layer, and a sealant layer are sequentially laminated from the outside.

15. An electrode assembly; a pouch-shaped battery case according to claim 1; an electrode lead connected to the electrode assembly and protruding to the outside of the pouch-shaped battery case via the terrace portion; and a lead film disposed between the electrode lead and the pouch-shaped battery case on the terrace portion; A pouch-type secondary battery, wherein a portion of the terrace portion is sealed along the periphery of the cup portion to form a sealing portion.

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