Side sealing device for stacked electrode body, secondary battery having stacked electrode body, and manufacturing method thereof

Abstract

A side sealing device for a stacked electrode body according to a preferred embodiment of the present invention includes: a mounting unit on which a stacked electrode body having a positive electrode, a separator, and a negative electrode cross-stacked is mounted; a pressing unit that applies pressure to both sides of a non-electrode side of the stacked electrode body from above and below, causing ends of the separators to abut against each other from above and below to form a sealing surface made of the separator; and an adhesive application unit that applies adhesive to the sealing surface to apply an adhesive between the separators forming the sealing surface and strengthen the sealing surface.

Description

[Technical Field]

[0001] The present invention relates to a side sealing device for a stacked electrode body, a secondary battery including the stacked electrode body, and a manufacturing method thereof, and more specifically to a side sealing device and a manufacturing method for forming a strong sealing surface on the non-electrode side of the stacked electrode body.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0072015, filed on June 14, 2022, and all contents disclosed in the documents of said Korean patent application are incorporated herein by reference. [Background technology]

[0003] Generally, types of secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, and lithium-ion polymer batteries.

[0004] These secondary batteries are attracting attention not only for use in small products such as digital cameras, P-DVDs, MP3Ps, mobile phones, PDAs (registered trademark), portable game devices, power tools, and E-bikes, but also as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), parallel hybrid electric vehicles (PHEVs), and the like.

[0005] In medium- to large-sized devices such as automobiles, medium- to large-sized battery modules in which multiple battery cells are electrically connected are used due to the need for high output and large capacity. However, since medium- to large-sized battery modules are preferably manufactured as small and lightweight as possible, prismatic batteries and pouch-shaped batteries, which can be charged with a high degree of integration and are light compared to their capacity, are mainly used as battery cells for medium- to large-sized battery modules.

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

[0007] The stack / fold type electrode assemblies disclosed in the applicant's Korean Patent Publication Nos. 2001-0082059 and 2001-0082060 have a full cell structure in which a positive electrode, a separator, and a negative electrode are sequentially stacked as a unit cell, and are manufactured by repeatedly winding up a separator sheet by a unit length with a plurality of full cells arranged on the separator sheet.

[0008] In such a stack / folding type electrode assembly, the outer periphery of every full cell is surrounded by a separator sheet, so that the relative positions of the layers constituting the electrode assembly are fixed.

[0009] 1 and 2 are diagrams illustrating a taping structure of a stacked electrode assembly according to the prior art.

[0010] Unlike stack / fold type electrode assemblies, the relative positions of the electrodes and separator are not fixed, so the sides of the electrode assembly are taped with tape to fix the relative positions of each layer. As shown in Figures 1 and 2, conventionally, tapes 21 and 22 surround the stack type electrode assembly in a strip shape.

[0011] 2, the stacked electrode assembly is formed by sequentially stacking a positive electrode 11, a separator 12, and a negative electrode 13. The separator 12 is disposed between the positive electrode 11 and the negative electrode 13 to prevent an electrical short circuit due to physical contact between the positive electrode 11 and the negative electrode 13.

[0012] In the case of such a stacked electrode assembly, the separator 12 is typically manufactured to be wider in width and length than the electrodes (positive electrode 11, negative electrode 13). The separator is stacked in a magazine or jig having a width corresponding to the width or length of the separator, and the electrodes are stacked on top of the separator, and this process is repeated to manufacture the stacked electrode assembly. The stacked electrode assembly is then fed as a whole into the subsequent process to manufacture a secondary battery.

[0013] Since the stacked electrode assembly is fed into a subsequent process as a single assembly, it is preferable to prevent the laminations from twisting during the subsequent process. To this end, conventionally, tape has been used to fix the laminations of the stacked electrode assembly so that they do not twist.

[0014] Specifically, tapes 21 and 22 are taped around the outer surface of the stacked electrode body, and at this time, the ends of the tapes overlap, creating a step equal to the thickness of the overlapping tapes. The step caused by the taping can lead to defects due to lithium deposition at the step area (see A in Figure 1).

[0015] Furthermore, during a taping process after the stacking process, the separators located at the top and bottom of the stacked electrode assembly may peel off or break, exposing the electrodes and causing defects.

[0016] Furthermore, when the electrolyte is injected into the battery case during the packaging process, the long side (non-electrode side) is not sealed, which can cause the end separator to peel off, resulting in electrode exposure. Furthermore, when the secondary battery is transported after packaging is complete, the vibrations in the electrolyte can cause waves, which can affect the peeled separator and cause it to break.

[0017] Furthermore, conventional stacked electrode bodies do not prevent foreign matter from entering the sides, and as foreign matter enters the stacked electrode body over time, there is a problem of low voltage failures caused by the foreign matter. Summary of the Invention [Problem to be solved by the invention]

[0018] An object of the present invention is to provide a side sealing device and manufacturing method for a stacked electrode assembly that can prevent the phenomenon of separation membrane tearing that can occur on the long side (non-electrode side) of the stacked electrode assembly.

[0019] According to one embodiment of the present invention, there is provided a side sealing device for a stacked electrode body, which first forms the long side of the stacked electrode body so that a sealing surface is formed on the long side of the stacked electrode body, and then applies an adhesive to firmly maintain the sealing surface formed by a separator.

[0020] According to an embodiment of the present invention, a stacked electrode assembly in which separators are continuously and closely attached to each other on the long side to form a sealing surface, and in which the separators are prevented from being damaged, and a secondary battery including the same are provided.

[0021] According to one embodiment of the present invention, there is provided a side sealing device and method that can effectively and easily impart rigidity to an extension portion of a separation membrane on a long side by vertically pressing and laterally pressing the extension portion of the separation membrane on the long side.

[0022] According to one embodiment of the present invention, a stacked electrode assembly and a secondary battery including the same are provided, which can effectively and easily protect a separator on the long side by strengthening the adhesive strength between the separators through vertical pressure on the separators and adhesive applied laterally, while still using a conventional separator. [Means for solving the problem]

[0023] To achieve the above-mentioned object, according to one embodiment of the present invention, a side sealing device for a stacked electrode body may be provided, including: a mounting unit on which a stacked electrode body in which a positive electrode, a separator, and a negative electrode are cross-stacked is mounted; a pressing unit that applies pressure to both sides of a non-electrode side of the stacked electrode body from above and below, causing ends of the separators to abut against each other from above and below to form a sealing surface made of the separator; and an adhesive application unit that applies adhesive to the sealing surface to apply an adhesive between the separators that form the sealing surface and strengthen the sealing surface.

[0024] The press unit may be configured to press an extension of the separator that extends further in the width direction of the stacked electrode body than the positive electrode or the negative electrode.

[0025] The press unit may include a roller unit that applies rotational pressure.

[0026] The roller unit preferably applies pressure such that the degree of bending of the separator increases from the center to the upper end and the lower end in the height direction of the stacked electrode assembly.

[0027] It is preferable that the roller unit includes an upper roller that is arranged in line with the longitudinal direction of the stacked electrode body and that applies pressure and rolling to the upper surface of the stacked electrode body while moving downward in the height direction of the stacked electrode body, and a lower roller that faces the upper roller but is arranged in line with the upper roller and that applies pressure and rolling to the lower surface of the stacked electrode body while moving upward in the height direction of the stacked electrode body.

[0028] The upper roller and the lower roller may pressurize and roll the stacked electrode assembly in a width direction thereof toward the outside of the stacked electrode assembly, thereby preforming the long side of the stacked electrode assembly. That is, a sealing surface may be preformed. The sealing surface may be formed so that ends of the separators are in close contact with each other.

[0029] It is preferable that the adhesive applicator is configured to move integrally with the lower roller, and to move independently of the lower roller when applying adhesive.

[0030] It is preferable that the adhesive applicator applies the adhesive while moving in the longitudinal direction of the stacked electrode body and in the height direction of the stacked electrode body according to a previously set application pattern.

[0031] The adhesive application unit may include an application frame having an X-axis guide rail provided in the longitudinal direction of the stacked electrode body, an X-axis moving unit provided on the X-axis guide rail so as to be movable left and right, and an adhesive application member that applies the adhesive toward the sealing surface while moving in accordance with the movement of the X-axis moving unit.

[0032] The adhesive application unit includes a Z-axis moving unit that is movable up and down along a Z-axis guide rail provided in the height direction of the stacked electrode body on the X-axis moving unit, and the adhesive application member can apply the adhesive toward the sealing surface while moving in accordance with the movement of the Z-axis moving unit.

[0033] According to this embodiment, a side sealing device for a stacked electrode body can be provided, which is characterized by including a main body frame on which the pressing unit and adhesive application unit are provided, and a main body part that adjusts the position and angle of the pressing unit and adhesive application unit by moving and rotating the main body frame.

[0034] The main body is preferably provided on each side of the placement portion.

[0035] The pressing parts are preferably provided so as to extend downward and upward from the upper and lower ends of the main frame, respectively.

[0036] The electrode assembly may include a position adjusting unit connected to the main body frame to move the main body frame together back and forth in a width direction of the stacked electrode assembly.

[0037] The apparatus may include an angle adjusting unit connected to the main body frame to rotate the main body frame in a horizontal direction.

[0038] It is preferable that the position adjustment unit and the main body frame are connected to each other via the angle adjustment unit.

[0039] The position adjustment unit may include a Y-axis guide rail arranged above the main body frame and aligned in the width direction of the stacked electrode body, a Y-axis moving member movably mounted on the Y-axis guide rail, and a drive motor that provides driving force to the Y-axis moving member.

[0040] According to this embodiment, it is preferable to include an inspection unit that generates alignment information for the stacked electrode body placed on the placement unit.

[0041] To achieve the above object, according to one embodiment of the present invention, there is provided a secondary battery including a stacked electrode assembly formed by cross-stacking a positive electrode, a separator, and a negative electrode, wherein sealing surfaces are provided on both sides of a non-electrode edge of the stacked electrode assembly, where extensions of the separator are in close contact with each other at the top and bottom, and the degree of curvature of the extensions of the separator increases from the center of the height of the stacked electrode assembly to the top and bottom ends, and an adhesive is applied to the sealing surfaces to apply adhesion between the extensions of the separator.

[0042] The sealing surface formed by the applied adhesive is preferably formed at the end of the extension of the upper and lower stacked separators, and the cross section of the non-electrode edge side of the stacked electrode body is preferably formed into a trapezoidal shape by the upper and lower separators and the sealing surface. [Effects of the Invention]

[0043] The present invention provides a side sealing device and a manufacturing method for a stacked electrode assembly that can prevent the separator from breaking on the long side (non-electrode side) of the stacked electrode assembly.

[0044] According to one embodiment of the present invention, a side sealing device for a stacked electrode body may be provided, which pre-forms the long side of the stacked electrode body so that a sealing surface is formed on the long side of the stacked electrode body, and then applies an adhesive to firmly maintain the sealing surface formed by a separator.

[0045] According to an embodiment of the present invention, a sealing surface is formed in which separators are continuously and closely attached to each other on the long side, thereby preventing damage to the separators, and a secondary battery including the same may be provided.

[0046] According to one embodiment of the present invention, a side sealing device and method can be provided that can effectively and easily impart rigidity to an extension portion of a separation membrane on a long side by vertically pressing and laterally pressing the extension portion of the separation membrane on the long side.

[0047] According to one embodiment of the present invention, a stacked electrode assembly and a secondary battery including the same can be provided, which can effectively and easily protect a separator on a long side by strengthening the adhesive strength between the separators through vertical pressure on the separators and adhesive applied laterally while still using a conventional separator.

[0048] According to one embodiment of the present invention, a pre-process such as forming an adhesive layer on each extension of a separator to strengthen the adhesion between the extensions of the separator can be eliminated, thereby preventing an increase in manufacturing costs and allowing a stacked electrode assembly to be easily manufactured using only a basic separator.

[0049] According to one embodiment of the present invention, after forming a sealing surface by closely adhering the extensions of the separators by applying pressure, the adhesion between the separators and the sealing can be strengthened through a single adhesive application process, thereby simplifying the manufacturing process of the stacked electrode body and improving production efficiency. [Brief explanation of the drawings]

[0050] [Figure 1]1 is a view illustrating a taping structure of a stacked electrode assembly according to the prior art; [Figure 2] 1 is a view illustrating a taping structure of a stacked electrode assembly according to the prior art; [Figure 3] 1 is a schematic diagram illustrating a configuration of a sealing device for a stacked electrode assembly according to an embodiment of the present invention; [Figure 4] 1 is a perspective view schematically illustrating a sealing device for a stacked electrode assembly according to an embodiment of the present invention; [Figure 5] 1 is a perspective view schematically illustrating a sealing device for a stacked electrode assembly according to an embodiment of the present invention; [Figure 6] 10A and 10B are diagrams illustrating a reference position, an approach position, and a coating frame position for a stacked electrode body according to an embodiment of the present invention. [Figure 7] 10A and 10B are diagrams for explaining the position adjustment of the main body with respect to the stacked electrode assembly according to one embodiment of the present invention. [Figure 8] 10 is a diagram illustrating a process in which the first main body frame is moved to a first approach position and the second main body frame is moved to a second approach position in one embodiment of the present invention. FIG. [Figure 9] 4 is a view illustrating a process in which a first rolling unit and a second rolling unit pressurize and roll a stacked electrode assembly in one embodiment of the present invention. FIG. [Figure 10] 4 is a view illustrating a process in which a first rolling unit and a second rolling unit pressurize and roll a stacked electrode assembly in one embodiment of the present invention. FIG. [Figure 11] (a) shows a schematic cross-section of a stacked electrode body before pre-forming according to one embodiment of the present invention, and (b) shows a schematic cross-section of a stacked electrode body pre-formed by a first rolling section and a second rolling section according to one embodiment of the present invention. [Figure 12] 10A and 10B are views illustrating a process in which a first adhesive applying unit and a second adhesive applying unit apply adhesive at an adhesive applying position and seal both long sides of a stacked electrode body according to an embodiment of the present invention. [Figure 13]10A and 10B are diagrams illustrating an example in which adhesive is applied to a sealing surface according to a previously set application pattern in an embodiment of the present invention. [Figure 14] FIG. 10 is a diagram schematically illustrating a partial perspective view of a stacked electrode assembly according to an embodiment of the present invention, in which adhesive is applied to a sealing surface provided on a long side of the stacked electrode assembly. [Figure 15] 1A and 1B are schematic perspective views of a stacked electrode assembly fabricated according to one embodiment of the present invention; [Figure 16] 16 is a schematic cross-sectional view taken along line xx in FIG. 15. DETAILED DESCRIPTION OF THE INVENTION

[0051] Hereinafter, a side-sealing device for a stacked electrode assembly, a stacked electrode assembly, and a method for manufacturing the stacked electrode assembly according to preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the accompanying drawings are for illustrative purposes only, and the scope of the side-sealing device for a stacked electrode assembly, the stacked electrode assembly, and the method for manufacturing the stacked electrode assembly of the present application is not limited to the accompanying drawings.

[0052] 3 to 5, a side sealing device 100 for a stacked electrode assembly according to a preferred embodiment of the present invention includes a mounting unit 110 and a control unit 130 for controlling the operation of the sealing device.

[0053] A stacked electrode assembly 200, in which a positive electrode 212, a separator 211, and a negative electrode 213 are cross-laminated, is placed on the placement unit 110. Sealing is performed on the long side of the stacked electrode assembly 200 placed on the placement unit 110. Therefore, the placement unit 110 can be called a side sealing station.

[0054] The mounting unit 110 may be provided with a gripper 115. The gripper 115 may fix the stacked electrode assembly 200 at the side sealing station. Specifically, the gripper 115 may be provided to grip both short sides of the stacked electrode assembly 200 to restrict movement of the stacked electrode assembly 200. Here, the short sides of the stacked electrode assembly 200 refer to side portions on which lead tabs are provided, and the long sides refer to side portions on which lead tabs are not provided. As shown in the figure, lead tabs may be formed on opposing short sides of the rectangular stacked electrode assembly 200, or on only one of the short sides. In some cases, a stacked electrode assembly may be manufactured with lead tabs formed on the long sides; however, for convenience, the term "long sides" used herein refers to opposing non-electrode sides.

[0055] The side sealing device 100 for a stacked electrode assembly according to a preferred embodiment of the present invention may include pressing parts 150a and 150b.

[0056] On the long side of the stacked electrode assembly, the separator width is greater than the width of the positive and negative electrodes. That is, on the long side of the stacked electrode assembly, the separator extends further on both sides than the positive and negative electrodes to form ends, which can be called separator extensions. In other words, on the long side, the positive and negative electrodes are not located directly above and below the separator end and separator extension, and a gap is formed between the separator and the positive and negative electrodes depending on their height or thickness. The separator end or extension may be damaged due to its weak rigidity. This may cause twisting in the stacked state during subsequent processes.

[0057] The press units 150a and 150b may be configured to press the plurality of separators positioned at the long side with a gap between them to form a sealing surface, that is, to press the plurality of separators so that they are bent or curved, more specifically, to press the bent separators so that they are in close contact with each other.

[0058] It is preferable that the pressure of the press units 150a and 150b be transmitted from the separators at the top and bottom to the central separator based on the height, i.e., thickness, of the stacked electrode assembly. The bending angle of the separator at the top and bottom is the largest, and the bending angle of the separator at the center is the smallest or maintained horizontally.

[0059] That is, by applying pressure from the press units 150a and 150b, all of the remaining separators except for the top and bottom separators can be pressed so as to be in close contact with the separators adjacent above and below. The separator located at the top is pressed downward by the separator directly above it due to the pressure of the press, and presses the separator directly below it downward. The separator located at the bottom is pressed upward by the separator directly below it due to the pressure of the press, and presses the separator directly above it upward. Through this pressing process, the separators are in close contact with each other vertically and converge toward the center. Therefore, due to this close contact, the separators on the long sides form a sealing surface.

[0060] The press units 150a and 150b may be in the form of press blocks or rollers, as will be described in detail below.

[0061] The side sealing device 100 for a stacked electrode assembly according to a preferred embodiment of the present invention may include reinforcing portions 160a and 160b that further strengthen the sealing surfaces formed by the pressing portions 150a and 150b. These reinforcing portions 160a and 160b may include a configuration in which an adhesive is applied to further impart adhesive strength to the sealing surfaces.

[0062] The sealing surface is formed by the separators that are bent by applying pressure to the ends or extensions of the separators through the press units 150a and 150b, and are then tightly adhered to each other. However, over time, the bent separators tend to return to their original shape, and this tendency may become more pronounced at the top and bottom ends. In other words, the adhesion of the separators may be released.

[0063] Therefore, a method for maintaining the tighter adhesion of the separator is required, and for this purpose, the present embodiment may include a sealing surface reinforcement portion.

[0064] The reinforcing portions 160a and 160b may be provided to form or provide adhesion between the ends of the separators at a sealing surface formed by the ends of the separators. Such adhesion may be provided by an applied adhesive, and details of the reinforcing portions will be described later.

[0065] The side sealing device 100 for a stacked electrode assembly according to a preferred embodiment of the present invention may include an inspection unit 120 that inspects the alignment of the stacked electrode assembly. The inspection unit 120 may inspect the alignment using vision. Therefore, the inspection unit 120 may be referred to as a vision inspection unit 120. The vision inspection unit 120 may be installed above the mounting unit 110. The vision inspection unit 120 photographs the stacked electrode assembly 200 and inspects the alignment of the long side of the stacked electrode assembly 200 based on the mounting unit 110. The vision inspection unit 120 may inspect the degree to which the long side of the stacked electrode assembly 200 matches the previously set alignment line L.

[0066] 7, the vision inspection unit 120 calculates the alignment angle θ of the long side of the stacked electrode body 200 with respect to the alignment line L of the mounting unit 110. The alignment angle θ is the angle of the long side of the stacked electrode body 200 with respect to the alignment line L of the mounting unit 110.

[0067] For example, if the long side of the stacked electrode assembly 200 is aligned with the previously set alignment line L, the alignment angle θ is calculated as "0." If the long side of the stacked electrode assembly 200 is twisted by 5° with respect to the previously set alignment line L, the alignment angle θ is calculated as "5°."

[0068] The side sealing device 100 according to this embodiment is a device that forms a sealing surface on the long side of the stacked electrode assembly 200 and strengthens the sealing surface. The formation and strengthening of the sealing surface must be performed uniformly along the entire length of both long sides. Therefore, it is preferable to perform sealing after aligning the stacked electrode assembly 200, or to perform sealing by reflecting and correcting misalignment.

[0069] The control unit 130 can control the subsequent side sealing process to be performed precisely by receiving the long side alignment information detected by the vision inspection unit 120. Details of how the sealing surface forming process is performed based on the alignment information will be described later.

[0070] According to a preferred embodiment of the present invention, the side sealing device may include a main body and main body portions 140a and 140b for performing the sealing surface forming process. Since the sealing surface forming process can be performed on both of the two opposing long sides of the stacked electrode assembly 200, a pair of main bodies is preferably provided. The two main bodies 140a and 140b are arranged facing the long sides of the stacked electrode assembly 200 across the mounting portion 110, allowing sealing surfaces to be formed simultaneously on both long sides of the stacked electrode assembly 200. Of course, one main body may be provided and a sealing surface may be formed on one side of the long side, followed by a sealing surface on the other side of the long side. In this case, the entire main body or the mounting portion may be movable. Specifically, the main body or the mounting portion may be rotated 180 degrees.

[0071] In this embodiment, for convenience of explanation, it is assumed that two main bodies 140a and 140b are provided, and in this case, they can be referred to as "first main body 140a" and "second main body 140b." The two main bodies are formed symmetrically to each other and can operate symmetrically. Therefore, a redundant description will be omitted, except for the differences between the first main body 140a and the second main body 140b.

[0072] The body portion and the structure forming the body portion described below may be a first body portion and the structure forming the body portion, or may be a single body portion and the structure forming the body portion.

[0073] The main body 140 a may be provided on one side of the mounting portion 110 so as to face one long side of the stacked electrode assembly 200 .

[0074] The body part 140a includes a body frame 141a, and the body frame 141a may include a pressing part 150a and a strengthening part 160a. The pressing part 150a and the strengthening part 160a may move relative to each other in the body frame 141a to form and strengthen a sealing surface.

[0075] Furthermore, the main body 140a may be a device for adjusting the positions and angles of the pressing part 150a and the reinforcing part 160a. That is, the main body 140a may be a device for adjusting the positions and angles of the pressing part 150a and the reinforcing part 160a based on alignment information so that the sealing surface is formed and reinforced by the pressing part 150a and the reinforcing part 160a being positioned and angled appropriately.

[0076] As described above, the pressing unit 150a may include a roller unit and may be a device that applies pressure using a pressure roller. The pressing unit 150a may also be referred to as a rolling unit 150a. The reinforcing unit 160a may also include an adhesive applicator that applies adhesive to the separator. Specifically, the reinforcing unit 160a may include an adhesive applicator that applies adhesive to the ends of the separator that form the sealing surface, thereby closely adhering and bonding the ends of the separator to each other. The reinforcing unit 160a may also be referred to as an adhesive applicator 160a.

[0077] The main body frame 141a may be provided with a rolling section 150a and an adhesive application section 160a. The main body frame 141a may be coupled to the angle adjustment section 143a and the position adjustment section 145a. The main body frame 141a may have a U-shaped structure with an open portion facing the long side of the stacked electrode body 200.

[0078] A rolling unit 150a may be provided on the open side of the main body frame 141a so as to be movable up and down in the height direction z of the stacked electrode body, and an adhesive applicator 160a may be provided so as to be movable up and down together with the rolling unit 150a. The adhesive applicator 160a may be provided so as to move independently of the rolling unit 150a to apply adhesive.

[0079] Specifically, the rolling unit 150a may include an upper roller 152a and a lower roller 154a.

[0080] The upper roller 152a may be positioned by extending downward from the upper side of the body frame 141a, and the lower roller 154a may be positioned by extending upward from the lower side of the body frame 141a.

[0081] The adhesive applicator 160a may be positioned extending from the middle of the main body frame toward the mounting portion, and may be positioned between the upper roller 152a and the lower roller 154a.

[0082] The rolling unit 150a and the adhesive applying unit 160a are attached to the main body frame 141a and can be provided to be movable integrally with the main body frame 141a.

[0083] Meanwhile, as described above, the vision inspection unit may generate alignment information for the electrode body on which the sealing surface is formed. Based on the alignment information, the control unit 130 needs to correct the positions and / or angles of the rolling unit 150a and the adhesive application unit 160a.

[0084] According to this embodiment, the rolling unit 150a and the adhesive applicator 160a are attached to the main frame 141a, and therefore the position and / or angle of the rolling unit 150a and the adhesive applicator 160a can be corrected by adjusting the position and / or angle of the main frame 141a. This is to form a uniform sealing surface along the entire long side, i.e., to apply pressure at the same position and with the same pressure depth along the entire long side.

[0085] 7, the angle adjusting unit 143a is coupled to the main body frame 141a and can rotate the main body frame 141a by an alignment angle θ from a first reference position P-1A based on the long side alignment information. Here, the first reference position P-1A may refer to a position where the main body frame 141a is arranged in line with the alignment line L of the mounting unit 110.

[0086] That is, the angle adjusting section 143a can adjust the position of the main frame 141a so that the rolling section 150a and the adhesive applying section 160a provided on the main frame 141a are positioned side by side on one side of the long side of the stacked electrode body 200.

[0087] 4, the position adjustment unit 145a may be coupled to the angle adjustment unit 143a and connected to the main body frame 141a. The position adjustment unit 145a may include a Y-axis guide rail 146a, a Y-axis moving member 147a, and a drive motor 148a.

[0088] The Y-axis guide rail 146a may be provided above the main body frame 141a in the width direction y of the stacked electrode body. A Y-axis moving member 147a may be provided on the Y-axis guide rail 146a so as to be movable back and forth.

[0089] The Y-axis guide rail 146a can be fixed to the ceiling surface in a permanently fixed configuration.

[0090] The Y-axis moving member 147a is coupled to the driving motor 148a and can move forward or backward along the Y-axis guide rail 146a when the driving motor 148a is operated. The Y-axis moving member 147a is connected to the main body frame 141a. Therefore, when the driving motor 148a is operated, the main body frame as a whole can move forward or backward toward the electrode body. This refers to the forward or backward movement of the rolling unit 150a and the adhesive application unit 160a, and the forward or backward movement here does not refer to movement directly for forming a sealing surface, but rather to movement for position correction before forming the sealing surface.

[0091] The Y-axis moving member 147a may be coupled with an angle adjusting portion 143a, that is, the angle adjusting portion 143a may be provided between the Y-axis moving member 147a and the main body frame 141a.

[0092] The main body frame 141a is coupled to the angle adjustment portion 143a and can be connected to the Y-axis moving member 147a. The position of the main body frame 141a relative to the stacked electrode assembly 200 is adjusted while moving in the movement direction of the Y-axis moving member 147a.

[0093] The angle adjustment portion 143a may be provided to rotate the main body frame 141a clockwise or counterclockwise.

[0094] The position adjustment unit 145a and the angle adjustment unit 143a can adjust the angle and position of the main body frame 141a in steps that have been previously set in the control unit .

[0095] 8, when the long side of the stacked electrode assembly 200 is pre-formed, the position adjustment unit 145a controls the operation of the drive motor 148a so that the Y-axis moving member 147a moves from the first reference position P-1A to the first entry position P-2A along the Y-axis guide rail 146a. Here, the first entry position P-2A is a position that has been set in advance by the control unit 130 between the center of the stacked electrode assembly 200 and one side of the long side of the stacked electrode assembly 200.

[0096] When the Y-axis moving member 147a reaches the first approach position P-2A, the position adjustment unit 145a stops the operation of the drive motor 148a. When the rolling unit 150a applies pressure to the stacked electrode body 200 in the vertical direction, the position adjustment unit 145a controls the operation of the first drive motor 148a so that the Y-axis moving member 147a moves backward from the first approach position P-2A toward the first reference position P-1A.

[0097] 11, during this process, the rolling unit 150a moves backward together with the main frame 141a, and pressurizes and rolls the stacked electrode assembly 200 up and down, thereby preforming one side of the long side of the stacked electrode assembly 200 so that the ends of the separators 211 on one side of the long side of the stacked electrode assembly 200 come together toward the outside of the stacked electrode assembly 200 and abut against each other, thereby forming a sealing surface.

[0098] The ends of the separators 211 of the pre-formed stacked electrode body 200 come into close contact with each other to form sealing surfaces. For example, the long sides of the pre-formed stacked electrode body 200 may have a triangular or trapezoidal cross section. In this embodiment, for ease of explanation, the surfaces formed by the ends of the separators 211 on one side of the long sides of the stacked electrode body 200 are referred to as "sealing surfaces 211a, 211b."

[0099] 9 and 10, the rolling unit 150a may include an upper lifting member 151a, an upper roller 152a, a lower lifting member 153a, and a lower roller 154a.

[0100] The upper roller 152a may be provided at the upper end of the main body frame 141a in the longitudinal direction x of the stacked electrode assembly 200. The upper roller 152a is a roller that pressurizes and rolls the extension of the separator on the top of the stacked electrode assembly 200.

[0101] The upper lifting member 151a is connected to the upper end of the main body frame 141a and the upper roller 152a. The upper lifting member 151a raises or lowers the upper roller 152a in the height direction z of the stacked electrode assembly.

[0102] When the Y-axis moving member 147a reaches the first entrance position P-2A, the upper lifting member 151a operates to pressurize the extension of the separator above the stacked electrode assembly 200 as the upper roller 152a descends.

[0103] When the Y-axis moving member 147a moves from the first entrance position P-2A to the first reference position P-1A, the upper lifting member 151a lifts the upper roller 152a. When the upper lifting member 151a lifts, the pressure of the upper roller 152a against the stacked electrode assembly 200 is released. Here, it is preferable that the pressure from the upper roller 152a is not applied directly to the electrodes, but is applied only to the extension of the separator.

[0104] The lower roller 154a is provided on the main body frame 141a in line with the longitudinal direction x of the stacked electrode assembly. The lower roller 154a is a roller that pressurizes and rolls upward the extension of the separation membrane at the bottom of the stacked electrode assembly 200. The lower roller 154a is provided at the lower end of the main body frame 141a so as to face the upper roller 152a.

[0105] The lower lifting member 153a is connected to the lower end of the main body frame 141a and the lower roller 154a. The lower lifting member 153a raises or lowers the lower roller 154a in the height direction z of the stacked electrode assembly.

[0106] When the Y-axis moving member 147a reaches the first entrance position P-2A, the lower lifting member 153a operates to pressurize the extension of the separator from the bottom of the stacked electrode assembly 200 upward as the lower roller 154a rises.

[0107] When the Y-axis moving member 147a moves from the first approach position P-2A to the first reference position P-1A, the lower lifting member 153a lowers the lower roller 154a. When the lower lifting member 153a lowers, the pressure applied by the lower roller 154a to the stacked electrode body 200 is released.

[0108] Referring to FIG. 12, through the operation of the main body 140a and the rolling unit 150a as described above, the ends of the separators 211 abut against each other at the top and bottom on one side of the long side of the stacked electrode body 200 to pre-form the sealing surface 211a, after which an adhesive can be applied.

[0109] 14, the adhesive application unit 160a applies adhesive 214 to the sealing surface 211a to strengthen the sealing surface on one of the long sides of the stacked electrode body 200. That is, the sealing surface can be strengthened by further imparting adhesive force to the generated sealing surface.

[0110] 12, adhesive applicator 160a may be provided on main body frame 141a. More specifically, adhesive applicator 160a may be provided on lower lifting member 153a. Therefore, the entire adhesive applicator 160a can move integrally with lower roller 154a.

[0111] The first adhesive applicator 160a includes a first applicator frame 161a, a first X-axis moving section 163a, a first Z-axis moving section 165a, and a first adhesive applicator member 167a.

[0112] The first coating frame 161a is coupled to the first lower lifting member 153a of the first rolling unit 150a. The first coating frame 161a is provided with a first lower roller 154a. The position of the first coating frame 161a is adjusted by the first lower lifting member 153a so that the adhesive coating units 160a and 160b correspond to the sealing surface.

[0113] The first application frame 161a is provided with a first X-axis guide rail 162a in the longitudinal direction x of the stacked electrode body. The first X-axis guide rail 162a is provided with a first X-axis moving section 163a. ​​The first X-axis moving section 163a is provided on the first X-axis guide rail 162a so as to be movable left and right. The first X-axis moving section 163a is provided with a first Z-axis guide rail 164a.

[0114] The first Z-axis guide rail 164a is provided alongside the height direction z of the stacked electrode body on one surface of the first X-axis moving part 163a facing the stacked electrode body 200. The first Z-axis guide rail 164a is provided with a first Z-axis moving part 165a.

[0115] The first Z-axis moving unit 165a is coupled to the first X-axis moving unit 163a so as to be movable up and down along the first Z-axis guide rail 164a. A first adhesive application member 167a is coupled to the first Z-axis moving unit 165a. The first Z-axis moving unit 165a operates to reciprocate up and down along the first Z-axis guide rail 164a at a reciprocating period according to a preset application pattern.

[0116] The first adhesive applicator 160a applies adhesive 214 toward the first sealing surface 211a on one side of the long side of the stacked electrode body 200. As the adhesive 214 hardens on the first sealing surface 211a of the stacked electrode body 200, one side of the long side of the stacked electrode body 200 is sealed.

[0117] The first adhesive application member 167a is moved left and right by the first X-axis moving section 163a and the first Z-axis moving section 165a according to a previously set application pattern, and at the same time, is moved back and forth up and down by the first Z-axis moving section 165a to apply adhesive 214 to the first sealing surface 211a.

[0118] Specifically, at the first application position P-3A, the first adhesive application unit 160a operates such that the first X-axis moving unit 163a moves from the start point to the end point on one side of the long side of the stacked electrode body 200 along the first X-axis guide rail 162a in the longitudinal direction x of the stacked electrode body according to a previously set application pattern, and the first Z-axis moving unit 165a moves back and forth up and down along the first Z-axis guide rail 164a in the height direction z of the stacked electrode body, so that the first adhesive application unit 160a applies adhesive 214 to the first sealing surface 211a.

[0119] Referring to Figure 6, the first application position P-3A faces the first sealing surface 211a and is aligned with one side of the long side of the stacked electrode body 200, but is spaced a predetermined distance from one side of the long side of the stacked electrode body 200.

[0120] By the operation of the adhesive applying unit 160a as described above, the sealing surface on one of the long sides of the stacked electrode body 200 can be more firmly strengthened.

[0121] Specifically, the sealing surface formed by pressure using rollers is formed by bending the extension of the separator and then applying pressure to the extension. If the extension of the separator has the same length before pressure application, the extension length after bending may be different. That is, the extension length becomes smaller toward the top and bottom ends and longer toward the center. In this case, the cross section of the sealing surface formed by the extension may have a substantially triangular shape.

[0122] The adhesive strength of the adhesive allows the sealing surface to be finally formed and firmly maintained with a substantially trapezoidal cross section. The adjacent separation membrane extensions on the upper and lower sides of the sealing surface are bonded together by the adhesive. That is, the separation membrane extensions are all adhesively bonded to each other, so that the entire sealing surface forms connecting ribs or connecting walls that connect all of the separation membrane extensions. This allows the separation membrane extensions to very effectively reinforce the rigidity.

[0123] As described above, in this embodiment, the main body units 140a, 140b are provided as a pair, and therefore each configuration can be provided symmetrically. The positions and angles of the main body frames 141a, 141b can be adjusted simultaneously on both sides, and the rolling units 150a, 150b and adhesive application units 160a, 160b can also be driven simultaneously on both sides.

[0124] Therefore, a description of the second main body portion 140b, its configuration, and its operation will be omitted.

[0125] Hereinafter, the method for controlling a sealing device according to an embodiment of the present invention will be described in more detail.

[0126] The control unit 130 receives long side alignment information from the vision inspection unit, calculates the alignment angle θ, the entry position, and the application position, and controls the operations of the angle adjustment units 143a and 143b, the position adjustment units 145a and 145b, the rolling units 150a and 150b, and the application frame units 160a and 160b according to pre-set steps.

[0127] Here, the entry position is a position set between the long side of the stacked electrode body 200 and the center of the stacked electrode body 200. The adhesive application position is a position on the long side of the stacked electrode body 200 where the sealing surface is provided.

[0128] In this embodiment, for convenience of explanation, the entry positions are divided into a "first entry position P-2A" and a "second entry position P-2B." Referring to Fig. 6, the first entry position P-2A is an arbitrary position on one side of the long side of the stacked electrode assembly 200. The second entry position P-2B is an arbitrary position on the other side of the long side of the stacked electrode assembly 200.

[0129] The control unit 130 controls the operation of the angle adjustment units 143a and 143b so that the main body frames 141a and 141b rotate by the alignment angle θ from the reference position. The control unit 130 controls the operation of the position adjustment units 145a and 145b so that the main body frames 141a and 141b move forward from the reference position to the entry position in the width direction y of the stacked electrode body.

[0130] Following this, the control unit 130 controls the operation of the position adjustment units 145a, 145b and the rolling units 150a, 150b so that the rolling units 150a, 150b apply pressure up and down to the stacked electrode body 200 at the entry position, and the main frame 141a, 141b is moved backward from the entry position to the reference position by the position adjustment units 145a, 145b, while the rolling units 150a, 150b apply pressure up and down to roll the long side of the stacked electrode body 200.

[0131] Next, after the operation of the rolling units 150a and 150b is completed, the control unit 130 moves the adhesive application units 161a and 161b to the application positions by the main body frames 141a and 141b.

[0132] Next, when the applicator frames 161a, 161b reach the application position, the control unit 130 controls the operation of the applicator frame units 160a, 160b to apply adhesive to the sealing surface of the stacked electrode body 200. This application of adhesive is performed via adhesive applicator members 167a, 167b, which are attached to the applicator frames 161a, 161b. Therefore, as the applicator frames 161a, 161b move, the applicator members 167a, 167b also move and apply adhesive.

[0133] In a conventional sealing process of a stacked electrode body 200, the adhesive tape may damage the upper and lower separators 211 of the stacked electrode body 200. However, referring to Figures 15 and 16, according to one embodiment of the present invention, it is possible to provide a stacked electrode body and a secondary battery including the same, in which both sides of the stacked electrode body 200 are sealed with an adhesive, thereby effectively preventing damage to the separators.

[0134] Furthermore, according to one embodiment of the present invention, the stacked electrode body 200 is fixed to both sides of the stacked electrode body 200 by an adhesive method, eliminating the step between the contact surface between the adhesive tape and the stacked electrode body 200 and the step between the overlapping adhesive tapes, which is common in the past, and thus preventing lithium deposition that occurs in the area where the adhesive tape adheres to the stacked electrode body 200.

[0135] In addition, according to one embodiment of the present invention, the stacked electrode body 200 is fixed to both sides of the stacked electrode body 200 by an adhesive method, thereby ensuring uniformity of the J / F surface pressure applied to the stacked electrode body 200 during the jig formation process for the stacked electrode body 200.

[0136] Furthermore, according to one embodiment of the present invention, both sides of the stacked electrode body 200 are fixed by adhesive, thereby preventing foreign matter from entering the stacked electrode body 200 during the activation process.

[0137] Furthermore, compared to sealing the stacked electrode body 200 using conventional adhesive tape, according to one embodiment of the present invention, the separation membrane 211 constituting the stacked electrode body 200 is sealed on the long side of the stacked electrode body 200, thereby reducing the thickness of the stacked electrode body 200 by the thickness of the adhesive tape surrounding the stacked electrode body 200, thereby making it possible to make the stacked electrode body 200 ultra-slim.

[0138] In the conventional stacked electrode body 200, when adhesive tape is sealed around the outer surface of the stacked electrode body 200, there was a risk that twisting would occur in the separation membrane 211, positive electrode 212, and negative electrode 213 that make up the stacked electrode body 200 during the process of the adhesive tape adhering to the stacked electrode body 200.

[0139] In contrast, according to one embodiment of the present invention, the gripper 115 is sealed to the long side of the stacked electrode body 200 while gripping the short side of the stacked electrode body 200, thereby preventing twisting of the separation membrane 211, positive electrode 212, and negative electrode 213 that make up the stacked electrode body 200 and improving the quality of the stacked electrode body 200.

[0140] The scope of the present invention is indicated by the claims that follow rather than by the detailed description, and all modifications and variations that fall within the meaning and scope of the claims and their equivalent concepts should be construed as being included within the scope of the present invention. [Industrial Applicability]

[0141] This is described in the detailed description of the invention.

Claims

1. a mounting portion on which a stacked electrode body in which a positive electrode, a separator, and a negative electrode are cross-laminated is mounted; a press unit that applies pressure to both sides of the non-electrode side of the stacked electrode body in an up-down direction, so that the ends of the separator come into close contact with each other at the top and bottom to form a sealing surface made of the separator; an adhesive applying unit that applies an adhesive to the sealing surface to strengthen the sealing surface by applying adhesive between the separation films that form the sealing surface; The adhesive application unit is a side sealing device for a stacked electrode body that applies the adhesive while moving in the longitudinal direction and the height direction of the stacked electrode body according to a pre-set application pattern.

2. 2. The side sealing device of claim 1, wherein the press unit is configured to press an extension of a separator that extends further in a width direction of the stacked electrode assembly than the positive electrode or the negative electrode.

3. The side sealing device for a stacked electrode assembly according to claim 2 , wherein the press unit includes a roller unit that applies rotational pressure.

4. 4. The side sealing device for a stacked electrode assembly according to claim 3, wherein the roller unit applies pressure such that the degree of bending of the separator increases from the center to the upper end and the lower end in a height direction of the stacked electrode assembly.

5. The roller portion is an upper roller arranged in line with the longitudinal direction of the stacked electrode body and moving downward in the height direction of the stacked electrode body to pressurize and roll the upper surface of the stacked electrode body; 5. The side sealing device for a stacked electrode body according to claim 4, further comprising: a lower roller that faces the upper roller but is arranged in parallel with the upper roller, and that pressurizes and rolls the lower surface of the stacked electrode body while moving upward in the height direction of the stacked electrode body.

6. 6. The side sealing device for a stacked electrode body according to claim 5, wherein the upper roller and the lower roller pressurize and roll the stacked electrode body up and down while moving toward the outside of the stacked electrode body in the width direction of the stacked electrode body, and pre-shape the long side of the stacked electrode body so that ends of the separation membranes abut against each other to form the sealing surface.

7. The side sealing device for a stack-type electrode assembly according to claim 5 , wherein the adhesive applicator is configured to move integrally with the lower roller and to move independently of the lower roller when applying adhesive.

8. The adhesive application section a coating frame provided with an X-axis guide rail in the longitudinal direction of the stacked electrode body; an X-axis moving unit provided on the X-axis guide rail so as to be movable left and right; 2. The side-sealing device for a stacked electrode body according to claim 1, further comprising: an adhesive application member that applies the adhesive toward the sealing surface while moving in accordance with the movement of the X-axis moving part.

9. The adhesive application section the X-axis moving unit includes a Z-axis moving unit that is provided to be movable up and down along a Z-axis guide rail that is provided in the height direction of the stacked electrode body, The side-sealing device for a stacked electrode body according to claim 8 , wherein the adhesive applicator applies the adhesive toward the sealing surface while moving in accordance with the movement of the Z-axis moving part.

10. 2. The side sealing device for a stacked electrode body according to claim 1, further comprising: a main body frame on which the pressing unit and the adhesive application unit are provided, and a main body that adjusts the position and angle of the pressing unit and the adhesive application unit by moving and rotating the main body frame.

11. The side sealing device for a stacked electrode assembly according to claim 10 , wherein the main body is provided on each side of the placement portion.

12. The side sealing device for a stack-type electrode assembly according to claim 11, wherein the pressing parts are provided by extending downward and upward from upper and lower ends of the main frame, respectively.

13. The side sealing device for a stacked electrode body according to claim 12 , further comprising a position adjusting unit connected to the main body frame to move the main body frame together back and forth in the width direction of the stacked electrode body.

14. The side sealing device for a stacked electrode body according to claim 13 , further comprising an angle adjusting unit connected to the main body frame to rotate the main body frame together in a horizontal direction.

15. The side sealing device for a stack-type electrode assembly according to claim 14 , wherein the position adjusting portion and the main body frame are connected to each other via the angle adjusting portion.

16. The position adjustment unit a Y-axis guide rail arranged in line with the width direction of the stacked electrode body and above the main body frame; a Y-axis moving member movably provided on the Y-axis guide rail; The side sealing device for a stack-type electrode assembly according to claim 13 , further comprising: a drive motor for providing a driving force to the Y-axis moving member.

17. The side sealing device for a stacked electrode body according to claim 1 , further comprising an inspection unit that generates alignment information for the stacked electrode body placed on the placement unit.

18. A secondary battery including a stacked electrode assembly formed by cross-stacking a positive electrode, a separator, and a negative electrode, The stacked electrode body has sealing surfaces formed by the ends of the separators, with the extensions of the separators being in close contact with each other at both sides of the non-electrode sides, and The degree of bending of the extension of the separator increases from the center to the upper and lower ends of the stacked electrode body, The secondary battery has an adhesive applied to the sealing surface to provide a fastening force between the extensions of the separator.

19. 20. The secondary battery of claim 18, wherein the sealing surface formed by the applied adhesive is formed at an end of an extension of a separator stacked in the upper and lower directions, and a cross section of a non-electrode edge side of the stacked electrode body is formed into a trapezoidal shape by the separators at the upper and lower ends and the sealing surface.

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