This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0136091 dated October 30, 2019, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification. [2] The present invention relates to a pressurizing jig and a method for manufacturing a secondary battery using the same, and more particularly, to a pressurizing jig that helps discharge gas by pressurizing a secondary battery during a cell activation process for a secondary battery, and a secondary battery manufacturing method using the same. background [3] In recent years, as the demand for portable electronic products such as notebook computers, video cameras, and portable telephones has rapidly increased, and development of electric vehicles, energy storage batteries, robots, satellites, etc. is in full swing, a high-performance secondary battery capable of repeatedly charging and discharging research is being actively conducted. [4] Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries. The self-discharge rate is very low and the energy density is high, attracting attention. In general, such secondary batteries may be classified into cylindrical or prismatic can-type secondary batteries and pouch-type secondary batteries depending on the exterior material or application form. [5] The secondary battery may be used in the form of a single secondary battery or in the form of a module in which a plurality of secondary batteries are electrically connected, depending on the type of external device in which it is used. For example, a small device such as a mobile phone can operate for a predetermined time with the output and capacity of one secondary battery, while a notebook computer, a portable DVD (Portable DVD), a small PC (Personal Computer), an electric vehicle, and a hybrid electric vehicle Medium-sized or large-sized devices such as automobiles require the use of a module including a plurality of secondary batteries due to problems of output and capacity. [6] A module is manufactured by connecting a protection circuit or the like to a core pack in which a plurality of secondary batteries are arranged and connected in series and/or in parallel. When a prismatic or pouch-type secondary battery is used as the unit secondary battery, it can be easily manufactured by stacking the wide surfaces to face each other and then connecting the electrode terminals by a connection member such as a bus bar. Therefore, when manufacturing a three-dimensional module having a hexahedral structure, a prismatic or pouch-type secondary battery is advantageous as a unit secondary battery. [7] Among them, the pouch-type secondary battery uses a metal layer (foil) and a multi-layer film of a synthetic resin layer coated on the upper and lower surfaces of the metal layer to construct the exterior, so that the battery is more cylindrical or prismatic than using a metal can. Since the weight can be significantly reduced, it is possible to reduce the weight of the battery, and it is attracting a lot of attention because it has the advantage of being able to change into various shapes. Also, its usage is gradually increasing. [8] In general, a pouch-type secondary battery is manufactured through a process of assembling a secondary battery and a process of cell activation of the secondary battery. [9] A conventional pouch case generally includes a lower case in which the electrode assembly is accommodated, and an upper case that seals the upper portion of the lower case. After the electrode assembly is accommodated in the housing of the lower exterior material, the edge around the housing of the lower exterior material and the corresponding edge of the upper exterior material are closely adhered, the closely adhered part is heat-sealed, the electrolyte is put in, and the remaining part is vacuum-sealed. is assembled [10] In the cell activation process, a secondary battery is mounted on a predetermined jig for smooth current flow, and charging/discharging is performed under conditions necessary for cell activation. In a secondary battery, due to its characteristics, in order to activate the positive electrode active material during the first cycle and to generate a stable surface film (SEI, Solid Electrolyte Interface) on the negative electrode, this cell activation process must be preceded. During the cell activation process, a large amount of gas is generated inside the secondary battery. Thereafter, the generated gas is removed through the opened or cut outlet, and the gas outlet portion is heat-sealed and sealed again. As described above, the process of discharging the gas inside the secondary battery and thermally sealing the discharge passage is often referred to as a degassing process. [11] In the case of a pouch-type secondary battery, if the gas generated inside the secondary battery is not efficiently removed during the cell activation process as described above, the gas occupies a certain space inside the secondary battery, causing the central part of the pouch exterior material to swell and deformation of the battery. and adversely affects battery performance, such as capacity and output, and battery life. [12] In some conventional technologies, the secondary battery after cell activation is fixed to a die and gas is removed by simple pressurization from the top, or the secondary battery is inserted into two opposing flat plate jigs and the cell is activated while applying pressure from both sides. have. The purpose of pressurization is to prevent gas generated during charging from being trapped inside the secondary battery. However, in the conventional pressurization method, since the gas inside the secondary battery corresponds to a fluid, when it receives pressure from the outside, it is dispersed in all directions without a certain direction. The gas dispersed in the other direction remains inside the secondary battery. [13] In addition, a technique of applying a plate-shaped member provided with a plurality of belt-shaped pressing parts to a pressing jig has also been attempted. The pressing jig forms a pattern in which a plurality of band-shaped pressing portions are repeated on the surface of the plate-shaped member, thereby imparting the directionality of the gas trapped when the secondary battery is pressurized. Thereafter, the trapped gas is discharged while the secondary battery is roll-pressed. However, in this technology, when the secondary battery is pressurized, as the pressurized region and the non-pressurized region are linearly divided, uniform pressurization over the entire area of ​​the secondary battery is not achieved. In addition, there is a limitation in that the discharge of the trapped gas is not sufficient by simply pressurizing the secondary battery at room temperature. [14] As described above, in the related art, the pressure applied during the cell activation stage charging may rather obstruct the discharge of gas inside the secondary battery. Accordingly, there is a high need for a technology capable of fundamentally solving these problems. DETAILED DESCRIPTION OF THE INVENTION technical challenge [15] The present invention was devised in consideration of the above problems, and the present invention is a problem in that the gas generated inside the secondary battery cannot be effectively removed in a short time, and the gas generated inside the secondary battery cannot be induced to a specific part of the secondary battery. An object of the present invention is to provide a pressure jig capable of simultaneously solving problems and a method for manufacturing a secondary battery using the pressure jig. means of solving the problem [16] The pressing jig according to the present invention is a pressing jig for sandwiching a secondary battery between a pair of opposing plate-shaped members in a cell activation process of a secondary battery and pressing the secondary battery from both sides. a pair of plate-shaped members provided with a plurality of independently formed protrusions; and a heating unit for heating the projections formed on the plate-shaped member. [17] In one example, the plurality of protrusions formed on the plate-shaped member have a dot-patterned structure. [18] In a specific example, the protrusion formed on the plate-shaped member includes a circular shape, an elliptical shape, or an n-gonal shape (n is an integer of 3 or more) in a cross-sectional shape parallel to the plate-like member. [19] In a specific example, the lower diameter of the protrusion formed on the plate-shaped member is equal to or greater than the upper diameter of the side in contact with the secondary battery based on the cross-sectional shape perpendicular to the plate-shaped member. For example, the projection formed on the plate-shaped member has a rectangular, triangular, semi-circular or trapezoidal cross-sectional shape perpendicular to the plate-shaped member. [20] In one example, a plurality of protrusions provided in a dot patterned form have the same average diameter of each protrusion. [21] In another example, the plurality of protrusions provided in a dot patterned form have a structure in which a protrusion having an average diameter D1 and a protrusion having an average diameter D2 are mixed, and a ratio of the average diameter D1 to D2 (D1/ D2) is a pressure jig in the range of 2 to 100. [22] In a specific example, the ratio of the formation area of ​​the projections having the average diameter D1 to the projections having the average diameter D2 (the formation area of ​​the projections having the average diameter D1/the formation area of ​​the projections having the average diameter D2) is in the range of 0.1 to 1.5. [23] In another example, the heating unit includes a heating coil mounted on the plate-shaped member. [24] [25] The present invention also provides a secondary battery manufacturing method using the above-described pressure jig. In one example, the secondary battery manufacturing method includes a cell activation step of performing a cell activation process for the secondary battery while heating and pressurizing with a press jig. [26] In one example, the method for manufacturing the secondary battery further includes, after the cell activation step, a gas removal step of pressurizing the cell-activated secondary battery to remove gas inside the secondary battery. [27] In a specific example, the gas removal step is performed by sandwiching a secondary battery between a pair of opposing plate-shaped members and pressing from both sides. [28] In another specific example, the gas removal step is performed by roll pressing the secondary battery in one direction. [29] For example, the secondary battery is a pouch-type secondary battery. Effects of the Invention [30] The pressurizing jig and the method for manufacturing a secondary battery using the same according to the present invention induce uniform pressurization of the secondary battery and smooth discharge of gas by providing a plurality of protrusions formed independently and spaced apart from each other on the pressurizing surface of the jig. In addition, the pressurization jig promotes the discharge of trapped gas inside the battery by heating the secondary battery in parallel when pressurizing the secondary battery using the jig in the cell activation process of the secondary battery. Brief description of the drawing [31] 1 is a schematic diagram illustrating a process of pressurizing a secondary battery using a pressurizing jig according to an embodiment of the present invention. [32] 2 and 3 respectively show the pressing surface of the pressing jig according to an embodiment of the present invention. [33] 4 is a schematic diagram illustrating a roll pressing process according to another embodiment of the present invention. Best mode for carrying out the invention [34] Hereinafter, the present invention will be described in detail. Prior to this, the terms or words used in the present specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, and the inventor must properly understand the concept of the term in order to best describe his invention. It should be interpreted as meaning and concept consistent with the technical idea of ​​the present invention based on the principle that it can be defined in [35] [36] The pressing jig according to the present invention is a pressing jig for sandwiching a secondary battery between a pair of opposing plate-shaped members in the cell activation process of the secondary battery and pressing the secondary battery from both sides. A pair of plate-shaped members provided with a plurality of projections formed as; and a heating unit for heating the projections formed on the plate-shaped member. [37] The pressing jig includes a pair of plate-shaped members for pressing the secondary battery, and has a structure provided with a plurality of independently formed protrusions spaced apart from each other on the pressing surface of each plate-shaped member. The projections formed on the pressing surface of the pressing jig according to the present invention have a structure formed independently by being spaced apart from each other, and through this, it is possible to implement even pressing on the front surface of the secondary battery. [38] In addition, according to the present invention, heating is simultaneously performed when the secondary battery is pressurized through the formation of the heating unit. That is, in the cell activation process of the secondary battery, the secondary battery is pressurized using the protrusion heated by the heating unit. When the secondary battery is heated, the internal gas is expanded, and the expanded gas can be discharged relatively easily. In the present invention, the internal gas is expanded through heating of the secondary battery, and at the same time, the expanded gas is easily released from the trapped portion through pressurization. [39] In addition, in the present invention, since the secondary battery is pressurized by a plate-shaped member having protrusions formed independently from each other, the gas released from the trap portion in the battery is easily discharged along the unpressurized region between the protrusions. In particular, according to the present invention, the pressure and heating of the secondary battery can be concentrated on a specific area by the protrusion provided on the pressing surface of the plate-shaped member. [40] In one embodiment, the plurality of protrusions formed on the plate-shaped member have a dot-patterned structure. Specifically, the independently formed protrusions and the spaced space between the protrusions serve to form a gas discharge flow path. The pressing jig according to the present invention forms a plurality of dot-patterned protrusions, thereby pressing the entire surface of the secondary battery with an even pressure in the cell activation step of the secondary battery. [41] In one embodiment, the protrusion formed on the plate-shaped member includes a circular shape, an elliptical shape, or an n-gonal shape (n is an integer equal to or greater than 3) in a cross-sectional shape parallel to the plate-like member. The n-gon includes a triangle, a quadrangle, a pentagon, a hexagon, and the like, and may have a shape close to a circle as the number of n increases. For example, n is an integer of 3 or more, and is an integer between 3 and 10. For another example, the protrusion formed on the plate-shaped member has a circular or quadrangular cross-sectional shape parallel to the plate-shaped member. In the present invention, the term 'circle' should be interpreted to include a case that is substantially round as well as a case that is substantially round in a physical sense. Specifically, in the n-gonal, when n exceeds 10, it can be interpreted as a substantially circular shape. [42] In a specific embodiment, the protrusion formed on the plate-shaped member is characterized in that, based on a cross-sectional shape perpendicular to the plate-shaped member, the lower diameter of the side in contact with the plate-shaped member is equal to or greater than the upper diameter of the side in contact with the secondary battery. Specifically, the protrusion may have a cylindrical shape, a hemispherical shape, or a hexahedral shape. For example, the projection formed on the plate-shaped member has a rectangular, triangular, semi-circular or trapezoidal cross-sectional shape perpendicular to the plate-shaped member. When the vertical cross section of the protrusion is rectangular, it means that the protrusion has a cylindrical or hexahedral shape. When the cross section of the protrusion is triangular, the protrusion has a sharp tip. When the cross section of the protrusion is semi-circular, the protrusion has a semi-spherical shape. In addition, when the cross-section of the protrusion has a trapezoidal shape, the protrusion has a wide lower diameter and a narrow upper diameter. [43] In one embodiment, a plurality of protrusions provided in a dot-patterned form have the same average diameter of each protrusion. This case includes a case in which a plurality of projections having the same or similar size are uniformly distributed on the pressing surface of the plate-shaped member. For example, the average diameter of the protrusions is in the range of 1 to 200 mm, in the range of 10 to 200 mm, in the range of 80 to 200 mm, in the range of 1 to 100 mm, or in the range of 10 to 50 mm. In addition, the distance between the respective projections is in the range of 1 to 100 mm, in the range of 1 to 80 mm, in the range of 10 to 100 mm, in the range of 50 to 100 mm, or in the range of 10 to 30 mm. [44] In another embodiment, the plurality of protrusions provided in a dot patterned form have a structure in which protrusions having an average diameter D1 and protrusions having an average diameter D2 are mixed. In this case, the diameter of the protrusions distributed on the pressing surface of the plate-shaped member is different from each other. For example, the present invention includes a case in which two types of protrusions having different diameters are distributed on the pressing surface of the plate-shaped member. Specifically, the ratio of the average diameters D1 and D2 (D1/D2) is in the range of 2 to 100, in the range of 2 to 20, in the range of 2 to 10, or in the range of 3 to 7. For example, the average diameter D1 is in the range of 50 to 200 mm, and the average diameter D2 is in the range of 1 to 100 mm. Specifically, the average diameter D1 is in the range of 70 to 120 mm, and the average diameter D2 is in the range of 10 to 50 mm. Further, the spacing between the respective projections is in the range of 1 to 100 mm, in the range of 1 to 80 mm, in the range of 10 to 100 mm, in the range of 50 to 100 mm, in the range of 10 to 70 mm, or in the range of 10 to 30 mm. [45] In a specific embodiment, the ratio of the formation area of ​​the projections having the average diameter D1 to the projections having the average diameter D2 (the formation area of ​​the projections having the average diameter D1/the formation area of ​​the projections having the average diameter D2) is in the range of 0.1 to 1.5. Specifically, the area ratio is in the range of 0.1 to 1, in the range of 0.1 to 0.5, in the range of 0.5 to 1.5, or in the range of 0.8 to 1.2. [46] In one embodiment, the pressure jig includes a heating unit for heating the projection formed on the plate-shaped member, the heating unit includes a heating coil mounted on the plate-shaped member. In the pressing jig according to the present invention, the heating unit has a structure mounted on the plate-shaped member, but the structure in which the heating unit is formed outside the plate-shaped member is not excluded. [47] [48] In addition, the present invention provides a secondary battery manufacturing method using the above-described pressure jig. Specifically, the pressure jig may be applied in the cell activation step of the secondary battery. In one embodiment, the method for manufacturing a secondary battery according to the present invention includes a cell activation step of performing a cell activation process while heating and pressurizing the secondary battery with the pressure jig. [49] The pressure jig according to the present invention is applicable to, for example, a manufacturing process of a pouch-type secondary battery. A pouch-type secondary battery has a structure in which a stack-type or stack/folding-type electrode assembly is embedded in a pouch-type battery case formed of an aluminum laminate sheet. The assembled secondary battery goes through a cell activation process in the manufacturing process of the battery. The cell activation process is performed by applying a current up to a predetermined voltage to the electrode assembly impregnated with the electrolyte. [50] During the initial charge/discharge process for cell activation, a protective film is formed on the surface of the electrode and a portion of the electrolyte is decomposed, generating a large amount of gas. In order to remove the generated gas inside the battery cell, a surplus is formed on one side of the battery case of the pouch-type battery. A gas pocket is formed as the gas inside the battery cell is collected in the surplus part of the battery case. One side of the gas pocket is opened to discharge the internal gas, and then the battery cell is sealed again. [51] In the present invention, the cell activation step to which the above-described pressure jig is applied is performed, and for the secondary battery that has undergone the cell activation step, a gas removal step of removing gas from the inside of the battery may be performed. In one embodiment, the method for manufacturing a secondary battery according to the present invention further includes, after the cell activation step, a gas removal step of pressurizing the cell-activated secondary battery to remove gas inside the secondary battery. [52] In the conventional pressurization method, the gas inside the secondary battery is dispersed in all directions without a certain direction, and some gas may be collected and removed in the surplus for gas collection, but the gas dispersed in the other direction remains inside the secondary battery. . However, the pressure jig according to the present invention applies a plate-shaped member provided with a plurality of protrusions formed independently from each other, thereby applying a uniform pressure to the front surface of the secondary battery while simultaneously collecting the trapped gas and inducing smooth discharge. can do. However, some trapped gases are not removed by simply mechanically pressurizing them. Since the pressure jig according to the present invention applies pressure and heat at the same time, the volume expansion of the trapped gas is induced, and the expanded gas can be smoothly removed by applying pressure. In addition, if necessary, it is possible to easily remove the gas remaining in the secondary battery in a subsequent process. [53] In one embodiment, the step of removing the gas may be performed by sandwiching a secondary battery between a pair of opposing plate-shaped members and pressing from both sides. In this case, the secondary battery that has undergone the cell activation step is sandwiched between a pair of plate-shaped members facing each other and pressurized from both sides, thereby discharging gas inside the battery. [54] In yet another embodiment, the step of removing the gas may be performed by roll pressing the secondary battery in one direction. In this case, the secondary battery that has undergone the cell activation step is roll-pressed in one direction, and through this, the gas remaining inside the battery is driven and discharged in one direction. [55] In one embodiment, the secondary battery is a pouch-type secondary battery. In addition, in the present invention, the secondary battery is, for example, a lithium secondary battery. The lithium secondary battery may include, for example, the electrode assembly described above; a non-aqueous electrolyte for impregnating the electrode assembly; and a battery case containing the electrode assembly and the non-aqueous electrolyte. For example, the secondary battery is a pouch-type lithium secondary battery. [56] The positive electrode has a structure in which a positive electrode mixture layer is laminated on one or both surfaces of a positive electrode current collector. The positive active material may be each independently a lithium-containing oxide, and may be the same or different. As the lithium-containing oxide, a lithium-containing transition metal oxide may be used. In one example, the positive electrode mixture layer includes a conductive material and a binder polymer in addition to the positive electrode active material, and, if necessary, may further include a positive electrode additive commonly used in the art. [57] The positive active material may be a lithium-containing oxide, and may be the same or different. As the lithium-containing oxide, a lithium-containing transition metal oxide may be used. [58] For example, the lithium-containing transition metal oxide is Li x CoO 2 (0.5