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

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 a stacked electrode body, and a manufacturing method thereof, and more specifically, to a side sealing device and manufacturing method for forming a strong sealing surface on the non-electrode edge side of a stacked electrode body.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0072015 dated June 14, 2022, and all contents disclosed in the documents of that 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 a plurality of battery cells are electrically connected are used due to the need for high output and large capacity. However, since it is preferable to manufacture medium- to large-sized battery modules as small and light as possible, square batteries and pouch-shaped batteries that 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 collector and a negative electrode collector to manufacture a positive electrode (cathode) and a negative electrode (anode), which are then stacked on both sides of a separator to form a stacked electrode assembly of a predetermined shape, and the stacked electrode assembly is then housed in a battery case, which is sealed after electrolyte is injected.

[0007] The stack / fold type electrode assembly disclosed in Korean Patent Publication No. 2001-0082059 and Korean Patent Publication No. 2001-0082060 by the present applicant has a full cell, which is a structure in which a positive electrode / separator / negative electrode are sequentially stacked, as a unit cell, and is manufactured by repeatedly winding up a separator sheet by a unit length with a plurality of full cells arranged on the long 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 each layer constituting the electrode assembly structure are fixed.

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

[0010] Unlike the stack / folding type electrode assembly, the relative positions between the electrodes and the separator are not fixed, so the sides of the electrode assembly are taped with tape to fix the relative positions between the layers. As shown in Figures 1 and 2, conventionally, tapes 21 and 22 surround the stack type electrode body 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 caused by 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 usually manufactured to be wider in width and length than the electrodes (positive electrode 11, negative electrode 13), and the separator is stacked in a magazine or jig having a width corresponding to the width or length of the separator, and the process of stacking the electrodes on the separator is repeated to manufacture the stacked electrode assembly. The stacked electrode assembly is then fed together into a 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, in the past, the laminations of the stacked electrode assembly were fixed by tape to prevent twisting.

[0014] Specifically, tapes 21 and 22 are taped around the outer surface of the stacked electrode body, but at this time, the ends of the tapes overlap, creating a step that is the thickness of the overlapping tapes. Due to the step caused by the taping, defects due to lithium deposition can occur at the step part (see A in FIG. 1).

[0015] In addition, during a taping process after the stacking process, the separators located at the upper and lower ends of the stacked electrode assembly may peel off or break, exposing the electrodes and causing defects.

[0016] In addition, when the electrolyte is injected into the battery case during the packaging process, the long side (non-electrode side) is not sealed, so the end separator may peel off, which may cause problems such as electrode exposure. In addition, when the secondary battery is transported after packaging is completed, the electrolyte may shake, generating waves, which may 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 the course of use, there is a problem that low voltage failure occurs due to 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 body that can prevent a separation membrane from breaking, which may occur on the long side (non-electrode side) of the stacked electrode body.

[0019] According to one embodiment of the present invention, there is provided a side sealing device for a stacked electrode body, in which a long side of the stacked electrode body is pre-shaped so that a sealing surface is formed on the long side of the stacked electrode body, and then an adhesive is applied so that the sealing surface composed of a separation film is firmly maintained.

[0020] According to an embodiment of the present invention, a sealing surface is formed by continuously adhering separators to each other on a long side, thereby preventing the separators from being damaged, and a secondary battery including the same is 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 of a separation membrane on a long side by vertically pressing and laterally pressing the extension of the separation membrane on the long side.

[0022] According to an 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 a long side by strengthening an adhesive between the separators through pressure applied from above and below the separator and an adhesive applied laterally while using a conventional separator as is. [Means for solving the problem]

[0023] In order 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, the side sealing device including: a mounting section on which a stacked electrode body in which a positive electrode, a separation film and a negative electrode are cross-stacked is mounted; a pressing section that presses both sides of a non-electrode side of the stacked electrode body from above and below, so that ends of the separation film abut against each other from above and below to form a sealing surface consisting of the separation film; and an adhesive application section that applies an adhesive to the sealing surface to apply an adhesive between the separation films forming the sealing surface and strengthen the sealing surface.

[0024] The press unit is preferably configured to press an extension portion of a separator that extends further in a 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] It is preferable that 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.

[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 moves downward in the height direction of the stacked electrode body to apply pressure rolling to the upper surface of the stacked electrode body, and a lower roller that faces the upper roller but is arranged in line with the upper roller and moves upward in the height direction of the stacked electrode body to apply pressure rolling to the lower surface of the stacked electrode body.

[0028] The upper roller and the lower roller may be configured to 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, thereby preforming the long side of the stacked electrode body. That is, a sealing surface may be preformed. The sealing surface may be formed such 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 during adhesive application.

[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 in which an X-axis guide rail is provided in the longitudinal direction of the stacked electrode body, an X-axis moving unit that is 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 section includes a Z-axis moving section 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 section, 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 section.

[0033] According to this embodiment, a side sealing device for a stack-type electrode body can be provided, which is characterized by including a main body frame in which the pressing unit and the adhesive application unit are provided, and a main body unit that adjusts the position and angle of the pressing unit and the 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 upper and lower ends of the main frame, respectively.

[0036] The electrode assembly may further include a position adjustment unit connected to the body frame for integrally moving the body frame back and forth in a width direction of the stacked electrode assembly.

[0037] The angle adjustment unit may include an angle adjustment unit connected to the body frame to rotate the body frame in a horizontal direction together with the body frame.

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

[0039] The position adjustment unit may include 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 mounted on the Y-axis guide rail, and a drive motor that provides a 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] In order to achieve the above-mentioned object, according to one embodiment of the present invention, there is provided a secondary battery including a stacked electrode body 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 side of the stacked electrode body, in which extensions of the separator are in close contact with each other at the top and bottom, and the degree of bending of the extensions of the separator increases from the center of the height of the stacked electrode body to both the top and bottom ends, and an adhesive is applied to the sealing surfaces to apply a fastening force between the extensions of the separator.

[0042] It is preferable that the sealing surface formed by the applied adhesive is formed at the end of the extended portion of the separators stacked vertically, and the cross section of the 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 surfaces. Effect of the Invention

[0043] According to the present invention, it is possible to provide a side sealing device and a manufacturing method for a stacked electrode body that can prevent a separator tearing phenomenon that may occur on the long side (non-electrode side) of the stacked electrode body.

[0044] According to one embodiment of the present invention, a side sealing device for a stacked electrode body may be provided, which pre-shapes a 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 so that the sealing surface composed of a separation film is firmly maintained.

[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 a 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 of a separation membrane on a long side by vertically pressing and laterally applying pressure to the extension of the separation membrane on the long side.

[0047] According to an 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 an adhesive between the separators through pressure applied from above and below the separator and an adhesive applied in a lateral direction while using a conventional separator as is.

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

[0049] According to one embodiment of the present invention, after the extensions of the separators are brought into close contact by applying pressure to form a sealing surface, 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 description of the drawings]

[0050] [Figure 1]1 is a diagram illustrating a taping structure of a stacked electrode assembly according to a conventional technique; [Diagram 2] 1 is a diagram illustrating a taping structure of a stacked electrode assembly according to a conventional technique; [Diagram 3] 1 is a schematic diagram of a sealing device for a stack-type electrode assembly according to one embodiment of the present invention; [Figure 4] 1 is a schematic perspective view of a sealing device for a stacked electrode assembly according to one embodiment of the present invention; [Diagram 5] 1 is a schematic perspective view of a sealing device for a stacked electrode assembly according to one embodiment of the present invention; [Figure 6] 11A to 11C are diagrams for explaining a reference position, an approach position, and a coating frame position for a stacked electrode body according to one embodiment of the present invention. [Figure 7] 11A to 11C are diagrams for explaining the position adjustment of a main body portion relative to a stacked electrode body according to an embodiment of the present invention. [Figure 8] FIG. 11 is a diagram illustrating a process in which a first main body frame is moved to a first approach position and a second main body frame is moved to a second approach position in one embodiment of the present invention. [Figure 9] FIG. 2 is a view illustrating a process in which a first rolling unit and a second rolling unit pressurize and roll a stacked electrode body in one embodiment of the present invention. [Figure 10] FIG. 2 is a view illustrating a process in which a first rolling unit and a second rolling unit pressurize and roll a stacked electrode body in one embodiment of the present invention. [Figure 11] (a) shows a schematic cross-section of a stacked electrode body before pre-molding according to one embodiment of the present invention, and (b) shows a schematic cross-section of a stacked electrode body pre-molded by a first rolling section and a second rolling section according to one embodiment of the present invention. [Figure 12] 4 is a diagram illustrating a process in which a first adhesive application unit and a second adhesive application unit apply adhesive at an adhesive application position and seal both long sides of a stack-type electrode body according to one embodiment of the present invention. FIG. [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 accordance with an embodiment of the present invention; [Figure 14] FIG. 2 is a schematic partial perspective view of a sealing surface provided on a long side of a stacked electrode body according to an embodiment of the present invention, in which an adhesive is applied to the sealing surface. [Figure 15] 1A and 1B are schematic diagrams illustrating a perspective view of a stacked electrode assembly fabricated according to one embodiment of the present invention; [Figure 16] A cross-sectional view taken along line xx in FIG. 15 is shown diagrammatically. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

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

[0052] 3 to 5, a side sealing device 100 for a stack-type electrode body 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 placement unit 110 may be provided with a gripper 115. The gripper 115 may fix the stacked electrode body 200 at the side sealing station. Specifically, the gripper 115 may be provided to grip both sides of the short side of the stacked electrode body 200 to restrict the movement of the stacked electrode body 200. Here, the short side of the stacked electrode body 200 refers to a side portion on which a lead tab is provided, and the long side refers to a side portion on which a lead tab is not provided. As shown in the figure, the lead tabs may be formed on the opposing short sides of the rectangular stacked electrode body 200, or on only one of the short sides. In some cases, the stacked electrode body may be manufactured in a shape in which a lead tab is formed on the long side, but for convenience, in this specification, the long side refers to the non-electrode side facing each other.

[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] At the long side of the stacked electrode body, the width of the separator is greater than the width of the positive and negative electrodes. That is, at the long side of the stacked electrode body, the separator extends further on both sides than the positive and negative electrodes to form ends. This can be called an extension of the separator. In other words, at the long side, the positive and negative electrodes are not located directly above and below the separator end and the extension of the separator, and a gap is formed between the separator and above and below depending on the height or thickness of the positive or negative electrodes. The end or extension of such a separator may be damaged due to its weak rigidity. In addition, twisting may occur in the stacked state in a subsequent process.

[0057] The press units 150a and 150b may be provided 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 as to bend or curve them, more specifically, to press the bent separators so as to be in close contact with each other.

[0058] It is preferable that the pressure of the press units 150a and 150b is transmitted from the uppermost and lowermost separators to the central separator based on the height, i.e., thickness, of the stacked electrode body. The bending angle of the separator at the uppermost and lowermost ends 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 to the press units 150a and 150b, all of the remaining separation membranes except for the separation membranes at the top and bottom ends can be pressed so as to be in close contact with the separation membranes adjacent above and below. The separation membrane located at the top is pressed downward by the separation membrane directly above due to the pressure of the press, and presses the separation membrane directly below downward. The separation membrane located at the bottom is pressed upward by the separation membrane directly below due to the pressure of the press, and presses the separation membrane directly above upward. Through this pressing process, the separation membranes converge toward the center while being in close contact with each other vertically. Therefore, due to this contact, the separation membranes on the long side form a sealing surface.

[0060] The press units 150a, 150b may be in the form of press blocks or rollers, the details of which will be described later.

[0061] The side sealing device 100 of a stack-type electrode body according to a preferred embodiment of the present invention may include reinforcing parts 160a and 160b that further strengthen the sealing surfaces formed through the pressing parts 150a and 150b. These reinforcing parts 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 separation membrane that is bent by applying pressure to the ends or extensions of the separation membrane through the press units 150a and 150b and is then in close contact with the other separation membrane. However, the bent separation membrane has a tendency to return to its original shape over time, and this tendency may be more pronounced at the top and bottom ends. In other words, the separation membrane may lose its adhesion.

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

[0064] The reinforcing parts 160a and 160b may be provided to form or provide adhesion between the ends of the separator at a sealing surface formed by the ends of the separator. Such adhesion may be provided by a coated adhesive, and the reinforcing parts will be described in detail below.

[0065] The side sealing device 100 for a stacked electrode body according to a preferred embodiment of the present invention may include an inspection unit 120 for inspecting the alignment of the stacked electrode body. The inspection unit 120 may inspect the alignment by vision. Therefore, the inspection unit 120 may be referred to as a vision inspection unit 120. The vision inspection unit 120 may be provided on the upper part of the mounting unit 110. The vision inspection unit 120 photographs the stacked electrode body 200 and inspects the alignment of the long side of the stacked electrode body 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 body 200 is matched with a previously set alignment line L.

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

[0067] For example, when the long side of the stacked electrode body 200 is matched with the already set alignment line L, the alignment angle θ is calculated as "0." When the long side of the stacked electrode body 200 is twisted by 5° with respect to the already set alignment line L, the alignment angle θ is calculated as "5°."

[0068] The side sealing device 100 according to the present embodiment can be said to be a device that forms a sealing surface on the long side of the stacked electrode body 200 and strengthens the sealing surface. The formation and strengthening of the sealing surface must be performed uniformly over the entirety of both sides of the long side. Therefore, it is preferable that sealing is performed after alignment of the stacked electrode body 200 is performed, or sealing is performed 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. Specific details of the sealing surface forming process being 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 parts 140a, 140b for performing the sealing surface forming process. Since the sealing surface forming process may be formed on both of the two opposing long side sides of the stacked electrode body 200, it is preferable that the main body parts are provided in pairs. The two main body parts 140a, 140b are arranged to face the long side sides of the stacked electrode body 200 with the mounting part 110 in between, and the sealing surface may be formed simultaneously on both sides of the long side of the stacked electrode body 200. Of course, one main body part may be provided, and after forming a sealing surface on one side of the long side, the sealing surface may be formed on the other side of the long side. In this case, the entire main body part may move, or the mounting part may move. Specifically, the main body part may rotate 180 degrees, or the mounting part may rotate 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 divided into a "first main body 140a" and a "second main body 140b". The two main bodies are formed symmetrically to each other and can operate symmetrically. Therefore, a duplicated explanation 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 portion 140 a can be provided on one side of the mounting portion 110 so as to face one long side of the stacked electrode body 200 .

[0074] The body part 140a may include a body frame 141a, and a pressing part 150a and a reinforcing part 160a may be provided on the body frame 141a. The pressing part 150a and the reinforcing part 160a may move relatively to each other in the body frame 141a to form and reinforce a sealing surface.

[0075] In addition, 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 forming and reinforcing a sealing surface by making the pressing part 150a and the reinforcing part 160a have appropriate positions and angles based on alignment information.

[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 include an adhesive applicator that applies adhesive to the separation membrane. Specifically, the reinforcing unit 160a may include an adhesive applicator that applies adhesive to the ends of the separation membrane that form the sealing surface to bring the ends of the separation membrane into close contact and bond with 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 an angle adjustment section 143a and a 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] On the open side of the main body frame 141a, a rolling unit 150a may be provided to be movable up and down in the height direction z of the stacked electrode body, and an adhesive applicator 160a may be provided to be movable up and down together with the rolling unit 150a. In addition, the adhesive applicator 160a may be provided 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 an upper side of the body frame 141a, and the lower roller 154a may be positioned by extending upward from a lower side of the body frame 141a.

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

[0082] The rolling unit 150a and the adhesive application unit 160a are attached to the body frame 141a and can be provided to be movable integrally with the 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, since the rolling unit 150a and the adhesive application unit 160a are attached to the main body frame 141a, the position and / or angle of the rolling unit 150a and the adhesive application unit 160a can be corrected by adjusting the position and / or angle of the main body frame 141a. This is to form a uniform sealing surface on the entire long side. That is, to apply pressure to the same pressure depth at the same position on the entire long side.

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

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

[0087] 4, the position adjustment unit 145a may be combined with 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 may be fixed to a 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 body frame 141a. Therefore, the body frame as a whole can move forward or backward toward the electrode body by the operation of the driving motor 148a. This means 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 mean the movement for directly forming the sealing surface, but the movement for correcting the position before forming the sealing surface.

[0091] The Y-axis moving member 147a may be coupled with an angle adjustment portion 143a, that is, the angle adjustment 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 a Y-axis moving member 147a. The position of the main body frame 141a relative to the stacked electrode body 200 is adjusted while moving in the moving direction of the Y-axis moving member 147a.

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

[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 are previously set in the control unit .

[0095] 8, when the long side of the stacked electrode body 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 already been set by the control unit 130 between the center of the stacked electrode body 200 and one side of the long side of the stacked electrode body 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 presses the stacked electrode body 200 up and down, 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, in this process, the rolling unit 150a, while moving backward together with the main frame 141a, pressurizes and rolls the stacked electrode body 200 up and down, and may pre-shape one side of the long side of the stacked electrode body 200 so that the ends of the separators 211 on one side of the long side of the stacked electrode body 200 come together toward the outside of the stacked electrode body 200 and abut against each other, thereby forming a sealing surface.

[0098] In the preformed stacked electrode body 200, the ends of the separation membranes 211 come into fine contact to form sealing surfaces. For example, the long sides of the preformed stacked electrode body 200 may form a triangular or trapezoidal cross section. In this embodiment, for ease of explanation, the surfaces formed by the ends of the separation membranes 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 section 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. The upper roller 152a is a roller that pressurizes and rolls the extension of the separation membrane on the upper part of the stacked electrode assembly 200.

[0101] The upper lifting member 151a is coupled 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 body.

[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 separation membrane above the stacked electrode body 200 as the upper roller 152a descends.

[0103] When the Y-axis moving member 147a moves from the first entry 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 body 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 separation membrane.

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

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

[0107] When the Y-axis moving member 147a moves from the first entry 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 of the lower roller 154a against the stacked electrode body 200 is released.

[0108] Referring to FIG. 12, by the operation of the body part 140a and the rolling part 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, and then an adhesive can be applied.

[0109] 14, the adhesive application unit 160a can apply 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, the adhesive applicator 160a may be provided on the main body frame 141a. More specifically, the adhesive applicator 160a may be provided on the lower lifting member 153a. Therefore, the entire adhesive applicator 160a can move integrally with the lower roller 154a.

[0111] The first adhesive applicator 160a includes a first application 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 first coating frame 161a is adjusted in position by the first lower lifting member 153a so that the adhesive coating units 160a and 160b correspond to the sealing surface.

[0113] A first X-axis guide rail 162a is provided on the first application frame 161a in the longitudinal direction x of the stacked electrode body. A first X-axis moving section 163a is provided on the first X-axis guide rail 162a. 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. A first Z-axis guide rail 164a is provided on the first X-axis moving section 163a.

[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 section 163a facing the stacked electrode body 200. A first Z-axis moving section 165a is provided on the first Z-axis guide rail 164a.

[0115] The first Z-axis moving part 165a is coupled to the first X-axis moving part 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 part 165a. The first Z-axis moving part 165a operates to reciprocate up and down along the first Z-axis guide rail 164a at a reciprocating period according to a previously set application pattern.

[0116] The first adhesive applicator 160a applies adhesive 214 toward a first sealing surface 211a on one side of a 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 in accordance with 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 is operated such that the first X-axis moving unit 163a moves from a start point on one side of the long side of the stacked electrode body 200 to an end point 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 a predetermined distance away 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 stack-type electrode body 200 can be strengthened more firmly.

[0121] Specifically, the sealing surface formed by pressing with the rollers is formed by bending the extension of the separation membrane and then pressing it closely. If the extension of the separation membrane has the same length before pressing, the extension length after bending may be different from each other. That is, the extension length becomes smaller toward the upper end and the lower end, and becomes 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 force 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 together so that the entire sealing surface forms a connecting rib or connecting wall that connects all of the separation membrane extensions. This allows the separation membrane extensions to reinforce the rigidity very effectively.

[0123] As described above, according to the present embodiment, the main body units 140a, 140b are provided in 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 the adhesive application units 160a, 160b can also be driven simultaneously on both sides.

[0124] Therefore, a description of the second main body portion 140b and its configuration and 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, 143b, the position adjustment units 145a, 145b, the rolling units 150a, 150b, and the application frame units 160a, 160b according to preset 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 "first entry position P-2A" and "second entry position P-2B". With reference to Fig. 6, the first entry position P-2A is an arbitrary position on one side of the long side of the stacked electrode body 200. And the second entry position P-2B is an arbitrary position on the other side of the long side of the stacked electrode body 200.

[0129] The control unit 130 controls the operation of the angle adjustment units 143a, 143b so that the main body frames 141a, 141b rotate by the alignment angle θ from the reference position. The control unit 130 controls the operation of the position adjustment units 145a, 145b so that the main body frames 141a, 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 while the main frames 141a, 141b are moved backward from the entry position to the reference position by the position adjustment units 145a, 145b, the rolling units 150a, 150b apply pressure and roll up and down on the long side of the stacked electrode body 200.

[0131] Next, after the rolling units 150a and 150b have completed their operations, 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 application frames 161a, 161b reach the application position, the control unit 130 controls the operation of the application 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 application members 167a, 167b, which are attached to the application frames 161a, 161b. Therefore, as the application frames 161a, 161b move, the application members 167a, 167b also move to apply the adhesive.

[0133] In a conventional sealing process of a stacked electrode body 200, the upper separator 211 and the lower separator 211 of the stacked electrode body 200 may be damaged by the adhesive tape. However, referring to Fig. 15 and Fig. 16, according to one embodiment of the present invention, a stacked electrode body and a secondary battery including the same can be provided in which both sides of the stacked electrode body 200 are sealed with an adhesive, thereby effectively preventing damage to the separator.

[0134] 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, and the step between the contact surface of the adhesive tape and the stacked electrode body 200 and the overlap step between the adhesive tapes are eliminated, thereby preventing lithium deposition that occurs in the area where the conventional adhesive tape adheres to the stacked electrode body 200.

[0135] In addition, according to one embodiment of the present invention, both sides of the stacked electrode body 200 are fixed 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 an embodiment of the present invention, both sides of the stacked electrode body 200 are fixed by an adhesive method, so that it is possible to prevent foreign matter from entering the stacked electrode body 200 during the activation process.

[0137] Furthermore, in comparison with 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 the adhesive tape is sealed around the outer surface of the stacked electrode body 200, there was a risk that the separation membrane 211, the positive electrode 212, and the negative electrode 213 that constitute the stacked electrode body 200 would become twisted in 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 constitute 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 set forth below rather than by the detailed description, and all modifications and variations derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in 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 presses both sides of the non-electrode side of the stacked electrode body in an up-down direction, and the ends of the separator are brought into close contact with each other in an up-down direction to form a sealing surface made of the separator; The side sealing device for a stack-type electrode body includes an adhesive applicator that applies an adhesive to the sealing surface to provide an adhesive force between the separators that form the sealing surface and strengthen the sealing surface.

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

3. The side sealing device for a stack-type electrode body according to claim 2 , wherein the press unit includes a roller unit for performing rotational pressure.

4. 4. The side sealing device of 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 includes: an upper roller that is arranged in line with the longitudinal direction of the stacked electrode body and that performs pressure rolling on the upper surface of the stacked electrode body while moving downward in the height direction of the stacked electrode body; 5. The side sealing device for a stacked electrode body as described in claim 4, further comprising: a lower roller that faces the upper roller but is arranged in parallel with the upper roller and 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 the ends of the separation membranes abut each other to provide the sealing surface.

7. The side sealing device for a stack-type electrode body 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. 2. A side sealing device for a stacked electrode body as described in claim 1, wherein the adhesive application unit applies the adhesive while moving in the longitudinal direction and the height direction of the stacked electrode body according to a previously set application pattern.

9. The adhesive application section includes: a coating frame having an X-axis guide rail provided in the longitudinal direction of the stacked electrode body; an X-axis moving part provided on the X-axis guide rail so as to be movable left and right; 9. The side-sealing device for a stack-type electrode body according to claim 8, further comprising: an adhesive application member that applies the adhesive toward the sealing surface while moving in response to the movement of the X-axis moving part.

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

11. 2. The side sealing device for a stack-type electrode body as described in claim 1, further comprising a main body frame on which the pressing unit and the adhesive application unit are provided, and a main body portion that adjusts the position and angle of the pressing unit and the adhesive application unit by moving and rotating the main body frame.

12. The side sealing device for a stack-type electrode body according to claim 11 , wherein the main body portion is provided on both sides of the placement portion.

13. The side sealing device of claim 12 , wherein the pressing parts are provided extending downward and upward from upper and lower ends of the main frame, respectively.

14. The side sealing device for a stacked electrode body according to claim 13 , further comprising a position adjustment part connected to the main body frame for integrally moving the main body frame back and forth in the width direction of the stacked electrode body.

15. The side sealing device of a stack-type electrode body according to claim 14 , further comprising an angle adjustment unit connected to the main body frame for rotating the main body frame in a horizontal direction together with the main body frame.

16. The side sealing device of claim 15 , wherein the position adjustment portion and the main body frame are connected to each other via the angle adjustment portion.

17. The position adjustment unit is 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 of claim 14 , further comprising: a drive motor for providing a driving force to the Y-axis moving member.

18. 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.

19. 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 on both sides of a non-electrode side, the sealing surfaces being formed by the extensions of the separators being in close contact with each other above and below, 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 adhesion between the extension of the separator.

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

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