Bag-shaped housing, pouch secondary battery, and method for manufacturing the same

Abstract

The present invention provides a pouch-shaped case for a pouch-type secondary battery and a pouch-type secondary battery including the pouch-shaped case, in which one corner of the pouch-shaped case is in close contact with a cooling plate. In the pouch-shaped case, by controlling the shape relationship among a forming portion, a receiving portion, and a sealing portion, the size of a sealing protrusion can be minimized, where the forming portion is formed to have a non-zero depth at the center in advance to accommodate one side of an electrode assembly, the receiving portion contacts a side surface of the electrode assembly when the pouch-shaped case is sealed, the sealing portion is for sealing opposite ends of the forming portion and the electrode assembly, and the sealing protrusion is formed by utilizing the mechanical properties of a metal laminate and a simplified die and punch after the electrode assembly is encapsulated.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2019 - 0121140, filed with the Korean Intellectual Property Office on September 30, 2019, the entire contents of which are incorporated herein by reference in their entirety. Technical field

[0003] The present invention relates to a bag - shaped case, a pouch - type secondary battery, and a method for manufacturing the same, and more particularly, to a pouch - type secondary battery in which one side surface is in close contact with a cooling plate and a method for manufacturing the same. Background art

[0004] A secondary battery cell is formed by encapsulating an electrode assembly including an anode, a cathode, a separator, and an electrolyte in a case. The electrode assembly can be classified into a wound jelly - roll type, which is wound in a state where a separator is interposed between a sheet - shaped anode and a sheet - shaped cathode coated with an active material; a stacked jelly - roll type, in which a plurality of positive electrode bodies and negative electrode bodies are sequentially stacked with a separator interposed therebetween; and a stacked - folded jelly - roll type, in which a stacked unit cell is wound with a long separator.

[0005] Such an electrode assembly is encapsulated in a container formed by pressing a metal into a cylindrical or rectangular parallelepiped shape, or is encapsulated in a bag formed of a multilayer film obtained by extruding a polymer raw material for use. Among them, pouch - type batteries are widely used because of their low manufacturing cost, light weight, and high formability.

[0006] As Figure 1 (a) shows, a related - art pouch - type secondary battery 10 includes an electrode assembly 1 and a bag - shaped case 2 for sealing the electrode assembly 1, and the bag - shaped case 2 includes a receiving portion 2a for receiving the electrode assembly 1 and a sealing portion 2b for sealing the electrode assembly 1. The related - art pouch - type secondary battery 10 is manufactured by the following method: receiving the electrode assembly 1 in the receiving portion 2a of the bag - shaped case 2, sealing the outer periphery of the sealing portion 2b, and then performing a seal so that one surface has a flat surface as shown in Figure 1 (b).

[0007] As described above, the electrode assembly 1 surrounded by the bag - shaped case 2 on three sides can reduce the area of the sealed side, thereby increasing the actual energy density at the same volume. However, when installing a cooling plate and the related - art pouch - type secondary battery 10 of a battery module, interference is caused to the cooling plate by a sealing protrusion 3 called a delta fin as shown in Figure 1 (b), resulting in a decrease in the cooling efficiency and energy density of the battery module.

[0008] In addition, the bag-shaped housing is formed of a metal laminated film, an aluminum metal layer, and an adhesive layer. The metal laminated film includes a base layer formed of a heat-bondable polyolefin-based resin and serving as a sealing material for the electrode assembly. The aluminum metal layer is used to block gas and moisture. The adhesive layer bonds the base layer and the metal layer. For a multi-layer laminated film, generally, a die and a punch in a molding die are used to stamp the multi-layer laminated film several times by deep drawing, and a bag-shaped housing is formed by a plurality of metal dies corresponding to the spaces for accommodating the electrode assembly at predetermined positions of the multi-layer laminated film.

[0009] In this case, due to the addition of corresponding facilities and processes, the productivity is reduced, and the size and design of the secondary battery must be changed as frequently as the development speed of the electronic device, resulting in a problem that the specific shape of the receiving portion formed on the secondary battery bag and the like will also be changed. SUMMARY OF THE INVENTION

[0010] An embodiment of the present invention aims to provide a pouch-type secondary battery in which, when sealing the pouch to seal the electrode assembly, by pre-adjusting the size and height of the sealing protrusions provided at the vertices of the opposite ends, one side of the pouch is closely attached to the cooling plate, thereby improving the cooling efficiency, and a method of manufacturing a bag-shaped housing for minimizing the sealing protrusions by a simple molding process.

[0011] In a general aspect, a bag-shaped housing for enclosing an electrode assembly, the electrode assembly including a plurality of electrode bodies stacked with a separator interposed therebetween, the bag-shaped housing including: a forming portion formed to have a non-zero depth at the center and accommodating a corner of the electrode assembly; a sealing portion provided on the outer periphery of the forming portion and sealing the accommodated electrode assembly; a notch portion provided between opposite ends of the sealing portion and the forming portion in the vertical direction; and a receiving portion that contacts the side surface of the electrode assembly when sealing the bag-shaped housing, wherein the forming portion includes a bottom portion and a height portion, the side surface of the electrode assembly is located in the bottom portion, the height portion extends upward from opposite ends of the bottom portion in the horizontal direction, the receiving portion is connected to both sides of the forming portion, and includes a forming connection portion and a sealing connection portion, the forming connection portion is formed on one side and connected to the height portion, the sealing connection portion is formed on the other side and connected to the sealing portion to have a step with respect to the forming portion, and the notch portion is connected to the sealing portion from opposite ends of the bottom portion of the forming portion at a predetermined non-zero inclination angle.

[0012] As another embodiment, the forming portion of the bag-shaped housing of the present invention may include a bottom portion in which the corners of the electrode assembly are located, and the receiving portion may be connected at both ends of the forming portion and includes a forming connection portion and a sealing connection portion. The forming connection portion is formed on one side and connected to the forming portion, and the sealing connection portion is formed on the other side and connected to the sealing portion to have a non-zero angle relative to the forming portion, and the notch portion is connected to the sealing portion from the opposite ends of the bottom portion of the forming portion at a predetermined non-zero inclination angle.

[0013] As another embodiment, the forming portion of the bag-shaped housing of the present invention may include a bottom portion and a height portion. The side surface of the electrode assembly is located in the bottom portion, and the height portion extends upward from the opposite ends of the bottom portion in the horizontal direction. The receiving portion may be connected to both sides of the forming portion and includes a forming connection portion and a sealing connection portion. The forming connection portion is formed on one side and connected to the height portion, and the sealing connection portion is formed on the other side and connected to the sealing portion to have a step relative to the forming portion, and the notch portion may be spaced apart from the opposite ends of the bottom portion of the forming portion at a predetermined non-zero distance to have a step relative to the bottom portion.

[0014] As another embodiment, the forming portion of the bag-shaped housing of the present invention may include a bottom portion in which the side surfaces of the electrode assembly are located, and the receiving portion may be connected at both ends of the forming portion and includes a forming connection portion and a sealing connection portion. The forming connection portion is formed on one side and connected to the forming portion, and the sealing connection portion is formed on the other side and connected to the sealing portion to have a non-zero angle relative to the forming portion, and the notch portion may be spaced apart from the opposite ends of the bottom portion of the forming portion at a predetermined non-zero distance to have a step relative to the bottom.

[0015] The bottom portion of the forming portion may have an uneven portion when it protrudes or depresses on its lower surface.

[0016] During the process of encapsulating the electrode assembly, the protruding or depressing form of the uneven portion may be maintained, and the uneven portion may be spread when sealing the bag-shaped housing.

[0017] On the other hand, the pouch-type secondary battery includes: an electrode assembly including a plurality of electrode bodies stacked with a separator interposed therebetween; and the above-mentioned bag-shaped housing.

[0018] The vertical length of the bottom portion where the electrode assembly is located may be less than or equal to the vertical length of the receiving portion.

[0019] The tab can be led out in the opposite direction of the electrode assembly, and the horizontal length of the electrode assembly parallel to the direction of the tab led out in the opposite direction of the electrode assembly can be greater than the length of the electrode assembly in the height direction.

[0020] In another general aspect, a pouch-type secondary battery module includes: a pouch-type secondary battery; a cooling plate for cooling the pouch-type secondary battery, wherein a formed portion of the pouch-shaped housing is in contact with the surface of the cooling plate.

[0021] In another general aspect, a method of manufacturing a pouch-type secondary battery includes: a plate arranging operation of arranging a metal laminate; a forming operation of stamping the plate with a punch in a single process to form the shape of a pouch-shaped housing under stamping conditions of temperature and pressure preset by predicting the mechanical properties of the plate; an electrode assembly inserting operation of inserting one side of the electrode assembly into and aligning it with the formed portion of the pouch-shaped housing; and a pouch-shaped housing sealing operation of sealing the sealing portion of the pouch-shaped housing.

[0022] The method may further include: a preparation operation of preparing a die having a cavity formed at the center before the plate arranging operation, wherein the forming operation is performed by stamping the punch between the cavities after the plate arranging operation.

[0023] Other features and aspects will become apparent from the following detailed description, the drawings, and the claims. Description of the Drawings

[0024] Figure 1 (a) and Figure 1 (b) are views showing a related-art pouch-type secondary battery.

[0025] Figure 2 is a perspective view of a pouch-type secondary battery according to an embodiment of the present invention before sealing.

[0026] Figure 3 (a) and Figure 3 (b) are respectively a plan view and a side view of a pouch-type secondary battery according to an embodiment of the present invention before sealing.

[0027] Figure 4 is a view showing protruding and recessed portions according to an embodiment of the present invention.

[0028] Figure 5 is a perspective view of a pouch-type secondary battery according to another embodiment of the present invention before sealing.

[0029] Figure 6 (a) and Figure 6 (b) are respectively a plan view and a side view of a pouch-type secondary battery according to another embodiment of the present invention before sealing.

[0030] Figure 7 Perspective view of a modified pouch secondary battery according to the present invention before sealing.

[0031] Figure 8 (a) and Figure 8 (b) are respectively a plan view and a side view of a modified pouch secondary battery according to the present invention before sealing.

[0032] Figure 9 Conceptual diagram showing a method of encapsulating the pouch secondary battery of the present invention.

[0033] Figure 10 View showing an encapsulated pouch secondary battery and an encapsulated secondary battery module of the present invention.

[0034] Figure 11 View showing a method of manufacturing a bag-shaped housing according to an embodiment of the present invention.

[0035] Figure 12 View showing a method of manufacturing a bag-shaped housing according to another embodiment of the present invention. Detailed Description

[0036] Hereinafter, the technical spirit of the present invention will be described in detail with reference to the accompanying drawings. The accompanying drawings are merely examples showing in detail the technical spirit of the present invention by way of example, and thus the technical spirit of the present invention is not limited to the form of the accompanying drawings.

[0037] Before the description, in the description of the electrode assembly and the bag-shaped housing in the claims and Figures 2 - 7 , the vertical direction, the horizontal direction, and the height direction represented by the coordinate system shown in Figure 2 will be used as a reference. The vertical direction, the horizontal direction, and the height direction represent directions extending to both sides in the display direction.

[0038] Embodiment of the pouch secondary battery according to the present invention

[0039] Referring to Figure 2 , the pouch secondary battery of the present invention includes an electrode assembly 100 and a bag-shaped housing 200. Each component will be described in detail as follows.

[0040] The electrode assembly 100 includes a plurality of electrode bodies, and a separator is inserted between the plurality of electrode bodies and stacked. Figure 2 The electrode assembly 100 shown can be a wound jelly roll type electrode assembly (a separator is inserted between a sheet-shaped positive electrode and a sheet-shaped negative electrode coated with an active material), or can be various types of electrode body assemblies.

[0041] The bag-shaped housing 200 is used to enclose and seal the electrode assembly 100, and may include an inner resin layer adjacent to the electrode assembly 100, an aluminum layer that maintains mechanical strength and prevents the inflow of moisture and oxygen, and an outer resin layer that serves as a protective layer.

[0042] Figure 3 (a) and Figure 3 (b) show the detailed structure of the bag-shaped housing 200. As shown in the figure, the bag-shaped housing 200 of the pouch-type secondary battery 1000 of the present invention includes a forming portion 210, a notch portion 220, a sealing portion 230, and a receiving portion 240.

[0043] In Figure 3 (a), the bag-shaped housing 200 in an unfolded state before enclosing the electrode assembly 100 is shown. In Figure 3 (b), the electrode assembly 100 is located inside the forming portion 210. In the unfolded position, the bag-shaped housing 200 may include a receiving portion 240 for accommodating the electrode assembly, and a sealing portion 230 formed on the periphery of the receiving portion 240. The sealing portion 230 forms a step with the receiving portion 240. The bag-shaped housing 200 may further include a forming portion 210 that is formed at the center of the bag-shaped housing and divides the receiving portion 240 into a first portion and a second portion located on opposite sides of the forming portion 210. As Figure 3 (b) shows, the forming portion may have a depth sufficient to tightly accommodate one side portion of the electrode assembly.

[0044] The bag-shaped housing 200 may further include a notch 220 (also referred to as a notch portion), which is formed in the sealing portion 230 and extends partially from the boundary between the forming portions 210 along the longitudinal axis of the forming portion 210 into the sealing portion 230.

[0045] The forming portion 210 may have a bottom portion 211 that is lower than the bottom surface of the receiving portion 240, and height portions 212a and 212b that connect the bottom portion 211 to the bottom surface of the receiving portion 240.

[0046] In Figure 3 (a) and Figure 3 (b) of the exemplary embodiment, when viewed from a top view, the notch has a triangular shape, the vertex of the triangle is located inside the sealing portion 230, and the bottom of the triangle is located at the boundary with the forming portion 210. The boundary of the notch with the forming portion 210 is aligned with the boundary of the sealing portion 230 and the receiving portion 240.

[0047] The notch 220 has a semi - pyramid shape with a rectangular base. The apex of the pyramid is located on the sealing portion such that when the bag - shaped housing is wrapped around the electrode assembly and the sealing portion 230 is sealed, the notch 220 has a complete pyramid shape.

[0048] The forming portion 210 has a recessed shape with a predetermined non - zero depth at the center of the bag - shaped housing 200, and includes a bottom portion 211 and height portions 212a and 212b.

[0049] The bottom portion 211 is for forming the bottom of the forming portion 210. The bottom portion 211 can be formed to have a width corresponding to the thickness of the electrode assembly 100 and a length corresponding to the vertical length of the electrode assembly. More specifically, the vertical length of the bottom portion 211 where the electrode assembly 100 is located can be less than or equal to the vertical length of the receiving portion 240. In addition, the bottom portion 211 can include an uneven portion 213 that protrudes or recesses.

[0050] The height portions 212a and 212b are formed at both ends of the bottom portion 211 in the horizontal direction and extend upward. Thus, the forming portion 210 can be formed by the bottom portion 211 and the height portions 212a and 212b.

[0051] The forming portion 210 provides a position where one side of the electrode assembly 100 is inserted during the manufacturing process of the pouch - type secondary battery 1000, and is used to support the inserted electrode assembly 100, thereby making the manufacturing of the secondary battery easier.

[0052] The notch portion 220 is used to control the wrinkles of the sealing protrusion formed when the bag - shaped housing 200 seals the electrode assembly 100 from three sides, and is connected to the sealing portion 230 at both ends of the bottom portion 211 of the forming portion 210 in the vertical direction at a predetermined non - zero inclination angle.

[0053] In one embodiment, the notch portion 220 can be formed to extend from both ends of the forming portion 210 in the vertical direction to protrude from the sealing portion 230, and can be designed in consideration of the specific shape of wrinkling after bending based on the physical properties of the metal laminate that is the material of the bag - shaped housing 200 and the process environment of sealing the electrode assembly 100. That is, the notch portion 220 serves as a guiding portion to allow the sealing portion 230 and the receiving portion 240 to easily enclose the electrode assembly 100 on both sides when three sides of the electrode assembly 100 are sealed, and is used to allow the sealing protrusion formed after sealing to be formed at a position higher than the bottom surface of the forming portion 210.

[0054] Therefore, the secondary battery can have a closer surface contact with the cooling plate, thereby improving the cooling efficiency and space efficiency and increasing the energy density of the secondary battery. Accordingly, the specific shape of the notch portion 220 is preferably restricted in association with the forming portion 210 and the sealing portion 230, and the protruding shape of the notch portion 220 may not be limited to Figure 2 and Figure 3 the shape shown, and may have various shapes consistent with the teachings herein.

[0055] The sealing portion 230 is a predetermined additional space provided at the periphery of the pouch-shaped case 200 when three sides of the electrode assembly 100 are sealed by the pouch-shaped case 200, and is used to maintain the airtightness of the electrode assembly 100 by heat fusion. Accordingly, the sealing portion 230 is preferably provided within the range of maintaining the minimum airtightness of the electrode assembly 100, and within the range of maintaining the airtightness, only a part of the sealing portion may be heat-fused.

[0056] The receiving portion 240 is formed to be adjacent to the electrode assembly 100 and fixes the received position of the electrode assembly when the electrode assembly 100 is three-side sealed with the pouch-shaped case 200.

[0057] A method of using the receiving portion 240 to fix the received position of the electrode assembly 100 will be described in more detail below. When the electrode assembly 100 is inserted into the forming portion 210 of the pouch-shaped case 200, the bottom portion 211 and the side surfaces of the electrode assembly 100 face each other, and the electrode assembly 100 is supported by the height portions 212a and 212b formed on both sides thereof, thereby being inserted into the forming portion 210. Herein, the insertion and support of the electrode assembly 100 can be assisted by the forming connection portion 250 formed to have a curved shape, and the height portions 212a and 212b are connected to the receiving portion 240 at the forming connection portion 250. Thereafter, the receiving portion 240 is closed in the direction of the electrode assembly 100 such that the sealing portions 230 are adjacent to each other on three sides. Herein, while placing the sealing connection portion 260 formed due to the step between the receiving portion 240 and the sealing portion 230 on the electrode assembly 100, the closing of the electrode assembly 100 can be assisted. Accordingly, the received position of the electrode assembly 100 can be fixed by the receiving portion 240.

[0058] As Figure 4As shown in (1), the side surface of the electrode assembly 100 is inserted into the recess of the forming portion 210 to determine the arrangement position. Here, in order to easily seal the electrode assembly 100 from three side surfaces by the bag-shaped housing 200, an uneven portion 213 that bends upward or downward may be formed on the lower surface of the forming portion 210. The uneven portion 213 formed on the lower surface of the forming portion 210 may be engaged with the bent portion of the notch portion 220 formed at the opposite ends of the forming portion 210 to reduce the size and height of the folded sealing protrusion formed at the corner when the electrode assembly 100 is enclosed and sealed by the bag-shaped housing 200. In addition, the uneven portion 213 can absorb the dimensional deviation of the bag-shaped housing 200 due to process errors, so that the bag-shaped housing 200 can stably enclose and seal three side surfaces of the electrode assembly 100.

[0059] Figure 4 (a)- Figure 4 (d) shows some examples of the uneven portion 213. The uneven portion 213 is formed in a shape that protrudes upward from the lower surface of the forming portion 210 or a shape that protrudes downward from the lower surface of the forming portion 210. In the case of the shape that protrudes upward from the lower surface of the forming portion 210, when the electrode assembly 100 is inserted into the forming portion 210, the uneven portion 213 can be used to attach the bag-shaped housing 200 more tightly to the electrode assembly 100 by the elastic energy stored during the formation of the uneven portion 213. In addition, the uneven portion 213 may have a plurality of protruding or recessed shapes.

[0060] Another embodiment of the pouch secondary battery according to the present invention

[0061] Figure 5 A pouch-type secondary battery according to another embodiment of the present invention includes an electrode assembly 100 and a bag-shaped housing 300. The same description as above will be omitted.

[0062] Figure 6 (a) is a plan view before sealing the bag-shaped housing 300. The bag-shaped housing 300 includes a forming portion 310, a notch portion 320, a sealing portion 330, and a receiving portion 340. Each part will be described in detail with reference to Figure 6 (b).

[0063] The forming portion 310 is formed by a bottom having a predetermined space at the center of the bag-shaped housing 300. The forming portion 310 provides a position for arranging the electrode assembly 100 during the manufacturing process of the pouch-type secondary battery 1000 and is used to easily fix the electrode assembly 100.

[0064] The notch portion 320 is used to control the shape of the sealing protrusion formed after the electrode assembly 100 is sealed on three sides by the bag-shaped housing 300. The notch portion 320 can be connected to the opposite end of the forming portion 310 in the vertical direction and is formed to protrude into the sealing portion 330.

[0065] The receiving portion 340 is formed to be adjacent to the electrode assembly 100 when the electrode assembly 100 disposed in the forming portion 310 is sealed on three sides by the bag-shaped housing 300, and is used to fix the receiving position of the electrode assembly 100.

[0066] Herein, a method for restricting the position where the electrode assembly 100 is received to the receiving portion 340 will be described in detail below. The side surface of the electrode assembly 100 is arranged to be adjacent to the forming portion 310 of the bag-shaped housing 300. Herein, the forming connection portion 350 connecting the forming portion 310 and the receiving portion 340 assists the receiving portion 340 and the forming portion 310 to form a predetermined angle and maintain an inclined surface. The receiving portion 340 extending from the forming connection portion 350 can be connected to the sealing connection portion 360 stepped with the sealing portion 330, such that when the sealing portion is adjacent to the three sides to surround the electrode assembly 100, the step of the sealing connection portion 360 can be placed on the electrode assembly 100 to assist it. Therefore, the receiving position of the electrode assembly 100 can be fixed by the receiving portion 340. Therefore, the receiving position of the electrode assembly 100 can be fixed by the receiving portion 340.

[0067] Herein, when the bag-shaped housing 300 seals the electrode assembly 100, according to the folded shape of the notch portion 320, a predetermined non-zero angle formed by the receiving portion 340 and the forming portion 310 can be formed such that the sealing protrusion can be located at a position higher than the bottom surface of the forming portion 310.

[0068] Another embodiment of the pouch secondary battery according to the present invention

[0069] Figure 7 A pouch-type secondary battery according to another embodiment of the present invention includes an electrode assembly 100 and a bag-shaped housing 400, and the bag-shaped housing 400 includes a forming portion 410, a notch portion 420, a sealing portion 430, and a receiving portion 440.

[0070] The notch portion 420 can be spaced apart from the opposite end of the forming portion 410 and can be controlled to have a shape such that the sealing protrusion formed during sealing is higher than the bottom of the forming portion 410. The distance D between the notch portion 420 and the forming portion 410 can be set as a distance for controlling the shape of the sealing protrusion formed during sealing.

[0071] The notch portion 420 may be spaced apart from the forming portion 410 and protrude on the sealing portion 430 in the direction of the opposite ends of the forming portion 410 in the vertical direction, so as to have a step with respect to the bottom surface of the sealing portion 430. The notch portion 420 may have various shapes other than the shape shown in Figure 8 A.

[0072] As Figure 8 shown, the notch portion 420 may have a predetermined distance B from the bottom surface of the forming portion 410. Here, the predetermined distance B may be formed such that after sealing the electrode assembly by measuring the metal laminate, the sealing process variables, etc., the sealing protrusion is formed at a position higher than the bottom surface of the bag-shaped case 400 according to an embodiment, so that the size of the sealing protrusion formed when sealing the electrode assembly can be controlled. The depth of the notch portion 420 may be less than the depth of the forming portion 410, so the predetermined distance B may be positive or negative. In addition, the predetermined distance B may be applied to the above-mentioned bag-shaped cases 200 and 300.

[0073] Hereinafter, a method of manufacturing the pouch-type secondary battery 1000 of the present invention will be described with reference to Figure 9 .

[0074] As Figure 9 (1) shows, the electrode assembly 100 is aligned with the bag-shaped case 300. Thereafter, as Figure 9 (2) shows, one side of the electrode assembly 100 is inserted or disposed on the forming portion 310. Subsequently, as Figure 9 (3) shows, the bag-shaped case 300 is folded based on the forming connection portions 350 on both sides. The receiving portion 340 preferably abuts against the electrode assembly 100, and the receiving portion 340 abuts against the electrode assembly 100 with the assistance of the forming connection portion 350. Here, the sealing protrusion is formed through the notch portion 320. The shape of the sealing protrusion can be controlled by the specific shape and value of the notch portion 320. Thereafter, a hot melt process for preparing the sealing portion 330 for the electrode assembly 100 may be performed through the sealing connection portion 360. Subsequently, as Figure 9 (4) shows, three sides of the sealing portion 330 are heat-sealed through the bag-shaped case 300 to seal three sides of the electrode assembly 100, thereby manufacturing the pouch-type secondary battery 1000. Here, it is preferable to fill the inside of the bag-shaped case 300 before the sealing portion 330 is completely sealed.

[0075] Figure 10 The packaged pouch-type secondary battery and the secondary battery module of the present invention are shown. As Figure 10As shown in (a), the pouch-type secondary battery 1000 of the present invention can be formed such that the surface corresponding to the forming portion is flat, so as to be in close contact with the cooling plate 900. Herein, through the above process, the sealing protrusions P1 and P2 are formed through the notch portion. The shapes and sizes of the sealing protrusions P1 and P2 can be controlled through the notch portion. In addition, the size and the gap distance D of the sealing protrusion P2 can be controlled through the notch portion to form a predetermined gap distance D with the cooling plate 900.

[0076] Meanwhile, as Figure 10 shown in (b), the pouch-type secondary battery module 2000 of the present invention can be formed by arranging the cooling plate 900 and a plurality of pouch-type secondary batteries 1000 in close contact with each other. Therefore, the heat generated in the pouch-type secondary battery 1000 can be easily transferred to the cooling plate 900. Compared with the related-art pouch-type secondary battery 10, when the secondary batteries are stacked in the module, since the shapes of the sealing protrusions P1 and P2 are controlled through the notch portion, the interference between the sealing protrusions P1 and P2 and the cooling plate 900 is reduced, thereby obtaining higher thermal efficiency and higher energy density per unit area. Meanwhile, in the electrode assembly 100, the tabs can be led out in opposite directions of the electrode assembly 100, and the horizontal length of the electrode assembly 100 parallel to the direction of the tabs led out in opposite directions of the electrode assembly 100 is greater than the length of the electrode assembly 100 in the height direction.

[0077] Hereinafter, with reference to Figure 11 and Figure 12 the manufacturing method of the pouch-type secondary battery 1000 according to the present invention will be described.

[0078] The manufacturing method of the bag-shaped cases 200, 300 or 400 includes a preparation step (S100), a plate arrangement step (S200), and a forming step (S300). Details of each step will be described.

[0079] First, the preparation step (S100) is a step of preparing a mold and a die for manufacturing the bag-shaped cases 200, 300 or 400. The male die for forming the bag-shaped cases 200, 300 or 400 is aligned with the die having a cavity formed at its center. The male die is aligned to be inserted into the cavity of the die.

[0080] The plate arrangement step (S200) is a step of arranging a metal laminate that can form the bag-shaped cases 200, 300 or 400 on the upper surface of the die.

[0081] The forming step (S300) is a step of forming a shape corresponding to the bag-shaped cases 200, 300, or 400 by stamping a metal laminate with a punch. Preferably, the mechanical properties of the metal laminate are measured and predicted, and the bag-shaped cases 200, 300, or 400 are formed with the punch under predetermined temperature, pressure, and stamping conditions in a single process.

[0082] The bag-shaped cases 200, 300, or 400 of the present invention can be formed in a single process through the preparation step (S100) to the forming step (S300). Different from the deep drawing for forming a bag-shaped case by repeated stamping through several consecutive stampings, in the present invention, a blank holder can be omitted, and the process of punching several times can be omitted, thereby reducing costs and maximizing production efficiency in mass production on an assembly line.

[0083] After forming the bag-shaped cases 200, 300, or 400, an electrode assembly insertion step (S400) of inserting and aligning the electrode assembly 100 into the forming portions 210, 310, or 410 of the bag-shaped case 200, the bag-shaped case 300, or the bag-shaped case 400 and a sealing step (S500) of sealing the sealing portions 230, 330, or 430 of the bag-shaped case 200, the bag-shaped case 300, or the bag-shaped case 400 are performed to manufacture a secondary battery. Here, in the process of manufacturing the pouch-type secondary battery of the present invention, an uneven portion is formed such that, during the process of encapsulating the electrode assembly with the bag-shaped case, the form in which the uneven portion protrudes or depresses is maintained, and the uneven portion can be formed such that the protruding or depressing form is unfolded when the bag-shaped case is sealed.

[0084] Figure 11 Some embodiments of manufacturing the bag-shaped case 200 of the present invention are shown. For the bag-shaped case 200, a metal laminate 500 is disposed on a die 600 having a die cavity formed at the center, and additionally, a support member 610 for forming a specific shape of the bag-shaped case 200 (i.e., a shape forming the connecting portion 250 and the sealed connecting portion 260) can be disposed. Thereafter, the laminate 500 is stamped under predetermined conditions reflecting the mechanical properties of the metal laminate 500, i.e., under stamping conditions such as temperature or pressure, and then, a shape corresponding to the forming portion 210, the notch portion 220, and the receiving portion 240 is stamped out and formed on the metal laminate 500 to manufacture the bag-shaped case 200. The punch 700 can include protrusions 710, 710a, and 710b that protrude outward to form the notch portion 220.

[0085] As Figure 11 (a) and Figure 11As shown in (b), preferably, the specific shape of the punch 700 is formed to correspond to the shape of the uneven portion 213 formed on the lower surface of the forming portion 210. In addition, it is also possible to form the same shape by simply stamping the forming portion 210 and the sealing connection portion 260 on the metal laminate 500 with the punch 700 capable of forming the Figure 11 (a)- Figure 11 As shown in (d), the bag-shaped housing 200. Thus, in one embodiment, the punch 700 may include an inclined surface 720. In addition, a part of the punch 700 in contact with the metal laminate 500 may be formed by a curved portion 730 to prevent cracking.

[0086] Figure 12 Another embodiment of manufacturing the bag-shaped housing 300 of the present invention is shown. In the bag-shaped housing 300, the connecting portion 350 and the sealing connection portion 360 are formed at a predetermined angle to form the receiving portion 340, and the punch 800 may have a corresponding shape. The punch 800 may include protrusions 810, 810a, 810b, and 810c that protrude outward to form the notch portion 320. In addition, similar to Figure 12 A- Figure 12 the shape of the punch 800 shown in C, the bag-shaped housing 300 of the present invention may be formed into the shape of the smallest punch 800 that forms the bag-shaped housing 300.

[0087] The present invention is not limited to the above embodiments, and the scope of application is diverse, and various modifications can be made without departing from the gist of the present invention as claimed in the claims. The present invention can be variously modified and has various embodiments. Although specific embodiments are shown and described in detail in the drawings, they are not intended to limit the present invention to the specific embodiments, and it should be understood that all modifications, equivalents, or substitutions are included within the technical scope and spirit of the present invention.

[0088] [Detailed description of main components]

[0089] 1000: Secondary battery

[0090] 2000: Secondary battery module

[0091] 100: Electrode assembly

[0092] 200, 300, 400: Bag-shaped housing

[0093] 210, 310, 410: Forming portion

[0094] 220, 320, 420: Notch portion

[0095] 230, 330, 430: Sealing portion

[0096] 240, 340, 440: Receiving portion

[0097] 250, 350: Forming connection portion

[0098] 260, 360: Sealing connection portion

[0099] 211: Bottom portion

[0100] 212a, 212b: Height portion

[0101] 500: Metal laminate

[0102] 600: Die

[0103] 610: Support member

[0104] 700, 800: Punch

[0105] 900: Cooling plate

[0106] 10: Related art pouch secondary battery

[0107] 1: Electrode assembly

[0108] 2: Pouch-shaped housing

[0109] 2a: Receiving portion

[0110] 2b: Sealing portion

[0111] 3: Sealing protrusion

Claims

1. A bag-shaped housing for enclosing an electrode assembly, the electrode assembly including a plurality of electrode bodies stacked with a separator inserted therebetween, the bag-shaped housing comprising: Forming portion, the forming portion is formed to have a non-zero depth at the center of the bag-shaped housing and accommodate a corner of the electrode assembly; Sealing portion, the sealing portion is disposed on the outer periphery of the forming portion and seals the accommodated electrode assembly; Notch portion, the notch portion is disposed between opposite ends in the vertical direction of the sealing portion and the forming portion; And Receiving portion, the receiving portion contacts the side surface of the electrode assembly when sealing the bag-shaped housing, wherein, the forming portion includes a bottom portion and a height portion, the corner of the electrode assembly is located in the bottom portion, and the height portion extends upward from opposite ends in the horizontal direction of the bottom portion; The receiving portion is connected to both sides of the forming portion and includes a forming connection portion and a sealing connection portion, the forming connection portion is formed on one side and connected to the height portion, and the sealing connection portion is formed on the other side and connected to the sealing portion; The receiving portion is connected to both sides of the forming portion, one side of the receiving portion is in direct contact with and connected to the height portion of the forming portion, the other side of the receiving portion is connected to the sealing portion through the sealing connection portion, and the receiving portion is formed as a continuous plane from one side to the other side; The receiving portion is formed to have a step relative to the sealing portion so that the receiving portion is integrally formed at a position lower than the sealing portion; The forming portion is formed to have a step relative to the receiving portion so that the bottom portion of the forming portion is formed at a position lower than the receiving portion, and The notch portion is connected to the sealing portion from opposite ends of the bottom portion of the forming portion at a predetermined non-zero inclination angle; When the sealing portion is sealed, the protrusion height of the sealing protrusion formed at the apex of opposite ends of the sealing portion is formed to be higher than the bottom portion of the forming portion.

2. A bag-shaped housing for enclosing an electrode assembly, the electrode assembly including a plurality of electrode bodies stacked with a separator inserted therebetween, the bag-shaped housing comprising: Forming portion, the forming portion is formed to have a non-zero depth at the center of the bag-shaped housing and accommodate one side of the electrode assembly; Sealing portion, the sealing portion is disposed on the outer periphery of the forming portion and seals the accommodated electrode assembly; Notch portion, the notch portion is disposed between opposite ends in the vertical direction of the sealing portion and the forming portion; And Receiving portion, the receiving portion contacts the side surface of the electrode assembly when sealing the bag-shaped housing, wherein, the forming portion includes a bottom portion, and the side of the electrode assembly is located in the bottom portion; The receiving portion is connected at both ends of the forming portion and includes a forming connection portion and a sealing connection portion, the forming connection portion is formed on one side and connected to the forming portion, and the sealing connection portion is formed on the other side and connected to the sealing portion to have a predetermined non-zero angle relative to the forming portion; The receiving portion is connected to both sides of the forming portion. One side of the receiving portion is in direct contact with and connected to the forming connection portion of the forming portion, and the other side of the receiving portion is connected to the sealing portion through a sealing connection portion. The receiving portion is formed as a continuous plane from one side to the other side. The receiving portion is formed to have a step with respect to the sealing portion so that the receiving portion is formed as a whole at a position lower than the sealing portion. The bottom portion of the forming portion is formed at a position lower than the receiving portion, and The notch portion is connected to the sealing portion from the opposite ends of the bottom portion of the forming portion at a predetermined non-zero inclination angle. When the sealing portion is sealed, the protrusion height of the sealing protrusion formed at the apex of the opposite ends of the sealing portion is formed to be higher than the bottom portion of the forming portion.

3. A bag-shaped housing for enclosing an electrode assembly, the electrode assembly including a plurality of electrode bodies stacked with a separator inserted therebetween, the bag-shaped housing comprising: Forming portion, which is formed to have a predetermined non-zero depth at the center and accommodates one corner of the electrode assembly; Sealing portion, which is provided on the outer periphery of the forming portion and seals the accommodated electrode assembly; Notch portion, which is provided between the opposite ends in the vertical direction of the sealing portion and the forming portion; And Receiving portion, which contacts the side surface of the electrode assembly when sealing the bag-shaped housing, Wherein, the forming portion includes a bottom portion and a height portion. The corner of the electrode assembly is located in the bottom portion, and the height portion extends upward from the opposite ends in the horizontal direction of the bottom portion. The receiving portion is connected to both sides of the forming portion and includes a forming connection portion and a sealing connection portion. The forming connection portion is formed on one side and connected to the height portion, and the sealing connection portion is formed on the other side and connected to the sealing portion. The receiving portion is connected to both sides of the forming portion. One side of the receiving portion is in direct contact with and connected to the height portion of the forming portion, and the other side of the receiving portion is connected to the sealing portion through a sealing connection portion. The receiving portion is formed as a continuous plane from one side to the other side. The receiving portion is formed to have a step with respect to the sealing portion so that the receiving portion is formed as a whole at a position lower than the sealing portion. The forming portion is formed to have a step with respect to the receiving portion so that the bottom portion of the forming portion is formed at a position lower than the receiving portion, and The notch portion is spaced apart from the opposite ends of the bottom portion of the forming portion at a predetermined non-zero distance to have a step with respect to the bottom portion. When the sealing portion is sealed, the protrusion height of the sealing protrusion formed at the apex of the opposite ends of the sealing portion is formed to be higher than the bottom portion of the forming portion.

4. A bag-shaped housing for enclosing an electrode assembly, the electrode assembly including a plurality of electrode bodies stacked with a separator inserted therebetween, the bag-shaped housing including: Forming portion, which is formed to have a predetermined non-zero depth at the center and accommodates one side of the electrode assembly; Sealing portion, which is provided on the outer periphery of the forming portion and seals the accommodated electrode assembly; A notch portion, the notch portion being provided between opposite ends in the vertical direction of the sealing portion and the forming portion; and A receiving portion, the receiving portion coming into contact with a side surface of the electrode assembly when sealing the bag-shaped housing, wherein the forming portion includes a bottom portion, and corners of the electrode assembly are located in the bottom portion, The receiving portion is connected at both ends of the forming portion and includes a forming connection portion and a sealing connection portion. The forming connection portion is formed on one side and connected to the forming portion, and the sealing connection portion is formed on the other side and connected to the sealing portion to have a non-zero angle with respect to the forming portion predetermined. The receiving portion is connected to both sides of the forming portion. One side of the receiving portion is in direct contact with and connected to the forming connection portion of the forming portion, and the other side of the receiving portion is connected to the sealing portion through the sealing connection portion. The receiving portion is formed as a continuous plane from one side to the other side. The receiving portion is formed to have a step with respect to the sealing portion so that the receiving portion is formed as a whole at a position lower than the sealing portion. The bottom portion of the forming portion is formed at a position lower than the receiving portion, and The notch portion is spaced apart from an opposite end of the bottom portion of the forming portion by a predetermined non-zero distance to have a step with respect to the bottom. When the sealing portion is sealed, a protrusion height of a sealing protrusion formed at a vertex of an opposite end of the sealing portion is formed to be higher than the bottom portion of the forming portion.

5. The bag-shaped housing according to any one of claims 1-4, wherein, The bottom portion of the forming portion has an uneven portion when its lower surface protrudes or depresses.

6. The bag-shaped housing according to claim 5, wherein, During the process of encapsulating the electrode assembly, the protruding or depressing form of the uneven portion is maintained, and when sealing the bag-shaped housing, the uneven portion is unfolded.

7. A pouch-type secondary battery, comprising: An electrode assembly, the electrode assembly including a plurality of electrode bodies, with a separator inserted between the plurality of electrode bodies and stacked; and A bag-shaped housing according to any one of claims 1-4.

8. The pouch-type secondary battery according to claim 7, wherein The vertical length of the bottom portion where the electrode assembly is located is less than or equal to the vertical length of the receiving portion.

9. The pouch-type secondary battery according to claim 8, wherein Tabs are led out in opposite directions of the electrode assembly, and The horizontal length of the electrode assembly parallel to the direction of the tabs led out in opposite directions of the electrode assembly is greater than the length of the electrode assembly in the height direction.

10. A pouch-type secondary battery module, comprising the pouch-type secondary battery according to claim 9 and a cooling plate for cooling the pouch-type secondary battery, Wherein, The forming portion of the bag-shaped housing is in contact with the surface of the cooling plate.

11. A method for manufacturing the pouch secondary battery according to claim 7, the method comprising: An operation of arranging a metal laminate plate; A forming operation of stamping a plate with a punch in a single process to form the shape of a bag-shaped housing under temperature and pressure stamping conditions preset by predicting the mechanical properties of the plate measured; An operation of inserting an electrode assembly, inserting one side of the electrode assembly into and aligning with the forming portion of the above bag-shaped housing; and An operation of sealing the bag-shaped housing, sealing the sealing portion of the bag-shaped housing.

12. The method according to claim 11, further comprising: A preparation operation of preparing a die having a cavity formed at the center before the plate arrangement operation, wherein the forming operation is performed by stamping a punch between the cavities after the plate arrangement operation.

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