Wheel tab forming device and wheel tab forming method

Abstract

A foil tab forming apparatus according to an embodiment of the present invention is configured to form at least one of a positive electrode foil tab and a negative electrode foil tab provided at an upper portion and a lower portion of an electrode assembly, respectively, and includes a preforming jig configured to pressurize and bend the foil tab while moving from an outer periphery of the electrode assembly toward a winding center of the electrode assembly, and a forming jig configured to move in a direction parallel to a winding axis of the electrode assembly and pressurize the foil tab that has been primarily bent by the preforming jig.

Description

[Technical field]

[0001] The present invention relates to a foil tab forming apparatus and a foil tab forming method.

[0002] This application claims priority to Korean Patent Application No. 10-2021-0030278 filed on March 8, 2021, and Korean Patent Application No. 10-2021-0137853 filed on October 15, 2021, and the entire contents disclosed in the specification and drawings of said application are incorporated herein by reference. [Background technology]

[0003] Conventional cylindrical secondary batteries have a structure in which a tab connecting an electrode assembly and an external terminal is welded to an uncoated portion of the electrode assembly. This structure has problems in that the current path is limited and the resistance of the electrode assembly itself is high.

[0004] In order to solve this problem, attempts have been made to increase the number of tabs connected to the electrode assembly, but there are limitations to the application of such methods. In order to solve this problem, it is conceivable to use the positive electrode uncoated portion and the negative electrode uncoated portion provided at the upper and lower parts of the electrode assembly as tabs. That is, it is conceivable to realize electrical connection using positive electrode foil tabs and negative electrode foil tabs that extend upward and downward, respectively, in parallel with the extension direction of the winding central axis of the electrode assembly.

[0005] In order to use the positive and negative uncoated parts extending to the top and bottom of the electrode assembly as tabs, it may be necessary to bend the positive and negative uncoated parts in order to increase the bonding area with the current collector plate.

[0006] Therefore, there is a need to develop a forming apparatus and a forming method using the forming apparatus that can smoothly perform the process of bending the positive electrode uncoated portion and the negative electrode uncoated portion of the electrode assembly. Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in view of the above problems, and an object of the present invention is to facilitate a process of forming a positive electrode foil tab and / or a negative electrode foil tab of an electrode assembly.

[0008] Another object of the present invention is to provide an electrode assembly having a positive foil tab and / or a negative foil tab that is uniformly formed over an entire area extending from an outer periphery of the electrode assembly to a winding center of the electrode assembly.

[0009] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0010] In order to achieve the above object, a foil tab forming apparatus according to one embodiment of the present invention is a foil tab forming apparatus for forming a foil tab of an electrode assembly having an outer periphery and a winding center portion defining a winding axis, and includes a forming jig configured to move along a direction parallel to the winding axis of the electrode assembly to pressurize the foil tab.

[0011] The foil tab forming device may further include a preforming jig configured to press and bend the foil tab while moving in a direction from an outer periphery of the electrode assembly toward a winding center of the electrode assembly.

[0012] The forming jig may be configured to pressurize the foil tab after the primary bending has been completed by the preforming jig.

[0013] The preforming jig may include a plurality of shutter blocks disposed around an outer periphery of the electrode assembly and moving in a direction toward a winding center of the jelly roll to bend the foil tab.

[0014] The shutter block may have a surface facing the foil tab that is inclined upward in a direction from an outer periphery of the electrode assembly toward the winding center.

[0015] The forming jig may have a width that is the same as or larger than the diameter of the electrode assembly.

[0016] The forming jig may be configured to rotate coaxially with a winding axis of the electrode assembly.

[0017] The forming jig may be configured to rotate clockwise or counterclockwise.

[0018] The forming jig may be configured to both compress and rotate the foil tab.

[0019] The forming jig may have a surface facing the foil tab that is inclined upward in a direction from an outer periphery of the electrode assembly toward the winding center.

[0020] The forming jig may include a first pressure block provided at a position on the foil tab that corresponds relatively to a first region adjacent to an outer periphery of the electrode assembly, and a second pressure block provided at a position on the foil tab that corresponds relatively to a second region adjacent to a winding center of the electrode assembly.

[0021] The pressure surface of the first pressure block and the pressure surface of the second pressure block may have the same inclination and define a surface of the forming jig that faces the foil tab.

[0022] The first and second pressure blocks may be configured to be independently movable along a direction parallel to a winding axis of the electrode assembly.

[0023] The forming jig may be configured such that a pressing surface of the first pressure block and a pressing surface of the second pressure block are flush with each other to move together toward the foil tab to perform a primary pressing, and then the second pressure block moves further toward the foil tab while the position of the first pressure block is maintained to perform a secondary pressing.

[0024] The forming jig may be configured such that, after the primary and secondary pressurization are completed, the bottom end of the second pressurizing block is positioned at the same height as or higher than the bottom end of the first pressurizing block.

[0025] The first pressure block and the second pressure block may be configured to rotate together or independently about the same axis as the winding shaft.

[0026] The forming jig may include a first pressure block provided at a position on the foil tab corresponding to a first region adjacent to an outer periphery of the electrode assembly, a third pressure block provided at a position on the foil tab corresponding to a third region adjacent to a winding center of the electrode assembly, and a second pressure block provided at a position on the foil tab corresponding to a second region located between the first region and the third region.

[0027] The forming jig may be provided as a pair of forming jigs disposed at opposite ends of the electrode assembly along a winding axis of the electrode assembly.

[0028] The pair of forming jigs may rotate in opposite directions relative to the same axis as the winding axis of the electrode assembly.

[0029] The preforming jig may be provided as a pair of preforming jigs disposed at opposite ends of the electrode assembly along a winding axis of the electrode assembly.

[0030] In order to solve the above-mentioned problems, a foil tab forming method according to one embodiment of the present invention is a method for forming a foil tab of an electrode assembly having an outer periphery and a winding center defining a winding axis, and includes the step of (S1) applying pressure to the foil tab in a direction parallel to the winding axis of the electrode assembly using a forming jig to bend the foil tab.

[0031] The foil tab forming method may further include, before step (S1), pressing and bending the foil tab in a direction from an outer periphery of the electrode assembly toward a winding center of the electrode assembly using a preforming jig.

[0032] The step (S1) may be a step of further bending the foil tab by applying pressure to the foil tab preformed in the step (S0).

[0033] The step (S0) may be performed using the preforming jig including a plurality of shutter blocks disposed around an outer periphery of the electrode assembly and moving along a direction toward a winding center of the electrode assembly to bend the foil tab.

[0034] The step (S0) may be performed using a preforming jig including a plurality of shutter blocks, the surfaces of which facing the foil tabs are inclined upward in a direction from the outer periphery of the electrode assembly toward the winding center.

[0035] The step (S1) may be performed using a forming jig having a width equal to or larger than the diameter of the electrode assembly.

[0036] The step (S1) may be performed using a forming jig configured to rotate coaxially with a winding axis of the electrode assembly.

[0037] The step (S1) may be performed using a forming jig configured to perform both the operation of pressing and rotating the foil tab.

[0038] In the step (S1), the forming jig may rotate clockwise so that the foil tab is oriented clockwise.

[0039] In the step (S1), the forming jig may rotate counterclockwise so that the foil tab is oriented counterclockwise.

[0040] The step (S1) may be performed using a forming jig having a surface facing the foil tab that is inclined upward in a direction from the outer periphery of the electrode assembly toward the winding center.

[0041] The step (S1) may be performed by a forming jig including a first pressure block provided at a position on the foil tab relatively corresponding to a first region adjacent to an outer periphery of the electrode assembly, and a second pressure block provided at a position on the foil tab relatively corresponding to a second region adjacent to a winding center of the electrode assembly.

[0042] The step (S1) may be performed using a forming jig in which the pressing surface of the first pressing block and the pressing surface of the second pressing block have the same inclination.

[0043] The step (S1) may be performed by a forming jig configured such that the first and second pressing blocks are independently movable along a direction parallel to a winding axis of the electrode assembly.

[0044] The step (S1) may include: (S11) performing a primary pressure by moving a pressure surface of the first pressure block and a pressure surface of the second pressure block toward the foil tab while being flush with each other; and (S12) after the step (S11), performing a secondary pressure by moving the second pressure block toward the foil tab while maintaining the position of the first pressure block.

[0045] After steps (S11) and (S12), the bottom end of the second pressurizing block may be positioned at the same height as or higher than the bottom end of the first pressurizing block.

[0046] The step (S1) may be performed by rotating the first and second pressing blocks together or independently on the same axis as the winding shaft.

[0047] The step (S1) may be performed by a forming jig including a first pressure block provided in the foil tab at a position corresponding to a first region adjacent to an outer periphery of the electrode assembly, a third pressure block provided in the foil tab at a position corresponding to a third region adjacent to a winding center of the electrode assembly, and a second pressure block provided in a region of the foil tab corresponding to a second region located between the first region and the third region.

[0048] The step (S1) may be performed using a forming jig in which a pressing surface of the first pressing block, a pressing surface of the second pressing block, and a pressing surface of the third pressing block have the same inclination.

[0049] The step (S1) may include: (S11) performing a primary press by moving a pressing surface of the first pressurizing block, a pressing surface of the second pressurizing block, and a pressing surface of the third pressurizing block toward the foil tab while the pressing surfaces of the first pressurizing block and the third pressurizing block are in the same plane; (S12) performing a secondary press by moving the second pressurizing block and the third pressurizing block toward the foil tab while the position of the first pressurizing block is maintained after the step (S11) and performing a secondary press; and (S13) performing a tertiary press by moving the third pressurizing block toward the foil tab while the positions of the first pressurizing block and the second pressurizing block are maintained after the step (S12).

[0050] The step (S1) may be performed using a pair of forming jigs disposed at opposite ends of the electrode assembly along a winding axis of the electrode assembly.

[0051] The step (S1) may be performed by rotating the pair of forming jigs in opposite directions relative to a winding axis of the electrode assembly.

[0052] The step (S0) may be performed using a pair of the preforming jigs disposed at opposite ends of the electrode assembly along a winding axis of the electrode assembly. Effect of the Invention

[0053] According to the present invention, a process for forming a positive electrode foil tab and / or a negative electrode foil tab of an electrode assembly can be smoothly performed.

[0054] Furthermore, according to the present invention, the positive and / or negative foil tabs of the electrode assembly may be uniformly formed over the entire region from the outer periphery of the electrode assembly to the winding center of the electrode assembly.

[0055] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention below.

[0056] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief description of the drawings]

[0057] [Figure 1] 2 is a view showing an electrode assembly in which the foil tab has been formed by the foil tab forming apparatus according to an embodiment of the present invention, and a current collector plate coupled to the foil tab. [Diagram 2] 2 is a view showing an electrode assembly in which the foil tab has been formed by the foil tab forming apparatus according to an embodiment of the present invention, and a current collector plate coupled to the foil tab. [Diagram 3] 5A to 5C are diagrams illustrating the operation of a preforming jig constituting a foil tab forming apparatus according to an embodiment of the present invention. [Figure 4] FIG. 2 is a diagram showing a forming jig constituting a foil tab forming apparatus according to an embodiment of the present invention. [Diagram 5] 5 is a diagram for explaining the operation of a second pressurizing block provided in the forming jig shown in FIG. 4. FIG. [Figure 6] 5 is a diagram for explaining a primary pressurization performed by the forming jig shown in FIG. 4. FIG. [Figure 7] 5 is a diagram for explaining a secondary pressurization performed by the forming jig shown in FIG. 4. FIG. [Figure 8] 11A to 11C are views for explaining a forming process using a forming jig constituting a foil tab forming apparatus according to another embodiment of the present invention. [Figure 9] 1A and 1B are diagrams showing an exemplary configuration of a forming jig of the present invention. [Figure 10] 1A and 1B are diagrams showing an exemplary configuration of a forming jig of the present invention. [Figure 11]FIG. 13 shows the orientation of the foil tab formed by the counterclockwise rotating forming jig of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0058] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as being in accordance with the meaning and concept of the technical idea of ​​the present invention, in accordance with the principle that the inventor himself can appropriately define the concept of the term in order to best describe the invention. Therefore, it should be understood that the embodiment described in this specification and the configuration shown in the drawings are only one most preferred embodiment of the present invention, and do not represent the entire technical idea of ​​the present invention, and therefore there may be various equivalents and modifications that can be substituted for them at the time of this application.

[0059] The foil tab forming apparatus of the present invention is an apparatus configured to smoothly form at least one of a positive electrode foil tab and a negative electrode foil tab provided at the upper and lower parts, respectively, of a jelly roll type electrode assembly.

[0060] 1 and 2, the structure of a foil tab T formed by the foil tab forming apparatus of the present invention is shown. The foil tab T refers to a first electrode uncoated portion extending upward (parallel to the Z axis in FIG. 1) and / or a second electrode uncoated portion extending downward (parallel to the Z axis in FIG. 1) along a direction parallel to the winding axis of the electrode assembly C. The electrode assembly C has a structure in which a laminate including a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode is wound around the winding axis. In this specification, a case in which the first electrode is a positive electrode and the second electrode is a negative electrode will be described as an example. The positive electrode includes a positive electrode uncoated portion formed at one end in the width direction of the laminate when the laminate is in a state before being wound, and the negative electrode includes a negative electrode uncoated portion formed at the other end in the width direction of the laminate when the laminate is in a state before being wound. When the laminate including such a positive electrode and a negative electrode is wound to form an electrode assembly C, an upper end of the electrode assembly C is provided with a positive electrode non-coated portion which is a region where the positive electrode active material is not applied, and a lower end of the electrode assembly C is provided with a negative electrode non-coated portion which is a region where the negative electrode active material is not applied.

[0061] The electrode plate constituting the positive electrode may be aluminum foil, and the electrode plate constituting the negative electrode may be copper foil. Accordingly, in this specification, the positive electrode uncoated portion and the negative electrode uncoated portion are referred to as foil tabs T. The positive electrode foil tab and the negative electrode foil tab extend upward and downward, respectively, of the electrode assembly C, i.e., extend in opposite directions.

[0062] A current collector P is bonded to the foil tab T. In order to improve the bonding strength between the current collector P and the foil tab T and reduce the electrical resistance at the bonding site, it is necessary to maximize the bonding area between the foil tab T and the current collector P by forming the bonding interface as flat as possible. For this purpose, the foil tab T may be bent so that an end of the foil tab T extends in a direction parallel to the current collector P. To make bending easier, a single foil tab that is continuously formed from the winding center of the electrode assembly C to the outermost periphery may be notched into a number of segments as shown in FIG. 2, for example, before bending.

[0063] The foil tab forming device of the present invention is characterized in that it is configured to be able to smoothly and uniformly bend the foil tab in the entire area around the outer periphery of the electrode assembly C and in the entire area from the outer periphery of the electrode assembly C to the winding center.

[0064] 3 and 4, the foil tab forming apparatus is an apparatus for forming at least one of a positive electrode foil tab and a negative electrode foil tab provided at the upper and lower parts of an electrode assembly C. The foil tab forming apparatus includes a forming jig 20 configured to form the foil tab T, and may further include a pre-forming jig 10 configured to perform pre-forming before forming the foil tab T by the forming jig 20. In the present specification, the foil tab forming apparatus of the present invention is described on the assumption that it includes both the pre-forming jig 10 and the forming jig 20. However, unlike this, the foil tab forming apparatus of the present invention may be configured not to include the pre-forming jig 10. In this case, as described below, the forming jig 20 of the present invention is configured to perform concentrated forming at different times for different regions of the foil tab T, so that uniform and accurate forming can be performed over the entire region of the foil tab T.

[0065] Referring to FIG. 3, the preforming jig 10 is configured to press and bend the foil tab T while moving from the outer periphery of the electrode assembly C toward the winding center of the electrode assembly C. The preforming jig 10 may be provided as a pair of preforming jigs 10 disposed at opposite ends of the electrode assembly C along the winding axis of the electrode assembly C. The preforming jig 10 may include a plurality of shutter blocks 11. The plurality of shutter blocks 11 are disposed around the outer periphery of the electrode assembly C and configured to bend the foil tab T by moving in a direction toward the winding center of the electrode assembly C. The shutter blocks 11 may have a surface facing the foil tab T that is inclined upward along a direction from the outer periphery of the electrode assembly C toward the winding center of the electrode assembly C. That is, each shutter block 11 may have a surface that is inclined upward such that the thickness of the shutter block 11 decreases from the outside toward the inside.

[0066] 4 and 5 together with FIG 3, the forming jig 20 is configured to move along a direction parallel to the winding axis of the electrode assembly C to pressurize the foil tab T that has been preformed by the preforming jig 10. The forming jig 20 may have, for example, a shape similar to a cylinder. The forming jig 20 may be provided as a pair of forming jigs disposed at opposite ends of the electrode assembly C along the winding axis of the electrode assembly C.

[0067] The forming jig 20 may have a width equal to or larger than the diameter of the electrode assembly C. This is to form the entire area of ​​the foil tab T when pressing using the forming jig 20. The forming jig 20 may be configured to rotate with respect to the same axis as the winding axis of the electrode assembly C. When the forming jig 20 is provided in a pair and is provided at both ends of the electrode assembly C in the height direction (direction parallel to the Z axis), the pair of forming jigs 20 may rotate in opposite directions. The forming jig 20 may be configured to perform both the operation of pressing and the operation of rotating the foil tab T. When both the pressing and the rotation are performed, the foil tab T can be bent more smoothly and naturally. When the rotating direction of the forming jig 20 is clockwise, the foil tab T may be oriented in the clockwise direction (see FIG. 2). Conversely, when the rotating direction of the forming jig 20 is counterclockwise, the foil tab T may be oriented in the counterclockwise direction (see FIG. 11).

[0068] The forming jig 20 may have a surface facing the foil tab T that is inclined upward in a direction from the outer periphery of the electrode assembly C toward the winding center. That is, the forming jig 20 may have a surface that is inclined upward such that the thickness of the forming jig 20 decreases from the outer side toward the center. This structure of the forming jig 20 can prevent the electrode assembly C from being damaged due to excessive force being applied to the foil tab T when the foil tab T is pressed, and can bend naturally.

[0069] The forming jig 20 may include a first pressing block 21 and a second pressing block 22. The first pressing block 21 is provided at a position on the foil tab T corresponding to a first region adjacent to an outer periphery of the electrode assembly C. The second pressing block 22 is provided at a position on the foil tab T corresponding to a second region adjacent to a winding center of the electrode assembly C. For example, when the forming jig 20 has a shape similar to a cylinder, the first pressing block 21 may have a shape similar to a hollow cylinder, and the second pressing block 22 may be disposed in the hollow portion of the first pressing block 21.

[0070] The pressing surface of the first pressing block 21 and the pressing surface of the second pressing block 22 may have substantially the same inclination. In this case, the pressing surface of the first pressing block 21 and the pressing surface of the second pressing block 22 may be substantially in the same plane. That is, the pressing surface of the first pressing block 21 and the pressing surface of the second pressing block 22 may be connected to each other to define a surface of the forming jig 20 facing the foil tab T.

[0071] The first and second pressure blocks 21 and 22 may be configured to be independently movable along a direction parallel to the winding axis (direction parallel to the Z-axis) of the electrode assembly C. For example, as shown in FIG 5, the second pressure block 22 may be additionally movable in a direction toward the foil tab T while the first pressure block 21 is stationary.

[0072] 6 and 7, the forming jig 20 may be configured to perform primary pressing by moving toward the foil tab T together with the pressing surface of the first pressing block 21 and the pressing surface of the second pressing block 22 on the same plane. In addition, the forming jig 20 may be configured to perform secondary pressing by further moving toward the foil tab T while the position of the first pressing block 21 is maintained after performing the primary pressing. In this manner, when the forming jig 20 includes a plurality of pressing blocks 21 and 22 and further pressing is performed using the pressing block 22 located closer to the center, more precise forming is possible. Depending on the inclination direction of the pressing surface of the forming jig 20, the bending point of the foil tab T during pressing moves toward the end of the foil tab T as it moves from the outer periphery of the electrode assembly C toward the winding center. Thus, when further pressing is performed using the second pressing block 22, the deviation of such bending point can be reduced.

[0073] Meanwhile, the forming jig 20 may be configured such that, after the primary and secondary pressurization are completed, the bottom end 22a of the second pressurizing block 22 is positioned at the same height as or higher than the bottom end 21a of the first pressurizing block 21. This is because if the pressurization by the second pressurizing block 22 is performed too deeply, the deviation of the bending position at the boundary point between the first pressurizing block 21 and the second pressurizing block 22 may become too large.

[0074] The first and second pressurizing blocks 21 and 22 may be configured to rotate together or independently on the same axis as the winding shaft of the electrode assembly C. That is, the first and second pressurizing blocks 21 and 22 may be connected together to one driving means to rotate, or may be connected to separate driving means to rotate independently.

[0075] The first and second pressurizing blocks 21 and 22 move toward the foil tab T with their respective pressurizing surfaces substantially in the same plane to bend the foil tab T by pressing and rotating (primary forming), and then, while maintaining the rotation of the first pressurizing block 21, the foil tab T may be further bent by pressing and rotating using the second pressurizing block 22 (secondary forming). The primary forming may be performed intensively on the first region of the foil tab T. Of course, while the first region is being formed intensively, the second region may also be formed at the same time. Also, the secondary forming may be performed intensively on the second region of the foil tab T. While the second region is being formed intensively, the first region may also be continuously formed.

[0076] While intensive forming is being performed on one of the first and second regions, whether forming is continued on the remaining regions can be determined by the vertical position of the forming jig 20 (direction parallel to the Z-axis).

[0077] Meanwhile, referring to Fig. 8, unlike the forming jig 20 shown in Figs. 4 to 7, a forming jig 30 including three pressurizing blocks 31, 32, and 33 is shown. However, the number of pressurizing blocks 21, 22, 31, 32, and 33 included in the forming jigs 20 and 30 is not limited to two or three, and a greater number of pressurizing blocks may be provided for more sophisticated forming.

[0078] The first pressing block 31 may be provided at a position on the foil tab T that corresponds relatively to a first region adjacent to an outer periphery of the electrode assembly C. The third pressing block 33 may be provided at a position on the foil tab T that corresponds relatively to a third region adjacent to a core side of the electrode assembly C, i.e., a winding center portion. The second pressing block 32 may be provided at a position on the foil tab T that corresponds relatively to a second region between the first region and the third region. The pressing surfaces of the first pressing block 31, the second pressing block 32, and the third pressing block 33 may have substantially the same inclination. Thus, the inclined surfaces of the first pressing block 31, the second pressing block 32, and the third pressing block 33 may define a surface of the forming jig 30 that faces the foil tab T.

[0079] As shown in FIG. 8, when the forming jig 30 includes a first pressurizing block 31, a second pressurizing block 32, and a third pressurizing block 33, the three pressurizing blocks 31, 32, and 33 may move and rotate toward the foil tab T while their pressurizing surfaces are substantially in the same plane, to form the foil tab T (primary forming). Through such primary forming, forming of the first region of the foil tab T may be performed intensively. Of course, while the first region is being formed intensively, forming of the second and third regions may also be performed simultaneously. After the primary forming is completed, the second and third pressurizing blocks 32 and 33 may move further while maintaining their pressurizing surfaces in the same plane, and may press and rotate in the same manner to form the foil tab T (secondary forming). Through such secondary forming, forming of the second region of the foil tab T may be performed intensively. At this time, the rotating state of the first pressurizing block 31 is continuously maintained, so that while the forming of the second region is being performed intensively, the forming of the first and third regions can also be continuously performed. After the additional pressurizing is performed by the second pressurizing block 32, the third pressurizing block 33 moves further to perform pressurizing and rotation to form the foil tab T (tertiary forming). By such tertiary forming, the forming of the third region of the foil tab T can be performed intensively. At this time, the rotating state of the first pressurizing block 31 and the second pressurizing block 33 is continuously maintained, so that while the forming of the third region is being performed intensively, the forming of the first and second regions can also be continuously performed.

[0080] While intensive forming is being performed on any one of the first, second and third regions, whether forming is continued on the remaining regions can be determined depending on the vertical position (direction parallel to the Z-axis) of the forming jig 20.

[0081] 3, 9, and 10, an exemplary embodiment of the preforming jig 10 is shown. The preforming jig 10 may include, for example, a shutter frame 12 having a plurality of slots 14. Each shutter block 11 may be supported in a corresponding slot 14 by a guide member 16 extending through the slot 14. The guide member 16 may move in the slot 14 by the shutter frame 12 rotating about an axis parallel to the winding axis of the electrode assembly C. The slot 14 may have a curved shape so that the shutter block 11 can easily move toward and away from the winding axis of the electrode assembly C. The overall movement of the shutter block 11 may be similar to, for example, the opening and closing of an iris. That is, the shutter block 11 may be configured to perform a closing operation in which the shutter block 11 moves toward the electrode assembly C disposed in a space formed in the center of the shutter frame 12 by being coupled to the shutter frame 12, and an opening operation in which the shutter block 11 moves away from the electrode assembly C. Meanwhile, the shutter block 11 can be opened and closed by rotating the shutter frame 12 or by moving the guide member 16 along the extension direction of the slot 14 .

[0082] Next, the foil tab forming method of the present invention will be described. The foil tab forming method of the present invention is a method for forming the foil tab T of the electrode assembly C by using the foil tab forming apparatus of the present invention as described above.

[0083] 3 to 8, the foil tab forming method of the present invention is a method for forming at least one foil tab T of a positive electrode foil tab and a negative electrode foil tab provided at the upper and lower parts, respectively, of an electrode assembly C.

[0084] The foil tab forming method is a method for forming a foil tab T of an electrode assembly C having an outer periphery and a winding center defining a winding axis, and includes the step of (S1) pressing and bending the foil tab T in a direction parallel to the winding axis of the electrode assembly C using a forming jig 20. The foil tab forming method may further include the step of (S0) pressing and bending the foil tab T in a direction from the outer periphery of the electrode assembly C toward the winding center of the electrode assembly C using a preforming jig 10 prior to the step (S1). In this case, the step (S1) may be a step of additionally bending the foil tab T by pressing the foil tab T that has been preformed in the step (S0).

[0085] The step (S0) may be performed using a preforming jig 10 including a plurality of shutter blocks 11 arranged around the outer periphery of the electrode assembly C and moving in a direction toward the winding center of the electrode assembly C to bend the foil tab T. The step (S0) may be performed using a preforming jig 10 including a plurality of shutter blocks 11 having a surface facing the foil tab T that is inclined upward in a direction from the outer periphery of the electrode assembly C toward the winding center. The step (S0) may be performed using a pair of the preforming jigs 10 arranged at both ends of the electrode assembly C on the opposite sides along the winding axis of the electrode assembly C. That is, the step (S0) may be a step of performing preforming on each of a first foil tab (first polarity) and a second foil tab (second polarity) provided at both ends of the electrode assembly C in a height direction (direction parallel to the Z axis). Such preforming for the first foil tab and preforming for the second foil tab may be performed simultaneously or with a time lag.

[0086] The step (S1) may be performed using a forming jig 20 having a width equal to or larger than the diameter of the electrode assembly C. The step (S1) may be performed using a forming jig 20 configured to rotate coaxially with the winding axis of the electrode assembly C. The step (S1) may be performed using a forming jig 20 configured to perform both the operation of pressing and the operation of rotating the foil tab T. In the step (S1), the forming jig 20 may rotate clockwise so that the foil tab T is oriented clockwise. Alternatively, in the step (S1), the forming jig 20 may rotate counterclockwise so that the foil tab T is oriented counterclockwise.

[0087] The step (S1) may be performed by a forming jig 20 having a surface facing the foil tab T that is inclined upward in a direction from the outer periphery to the winding center of the electrode assembly C. The step (S1) may be performed by a forming jig 20 including a first pressure block 21 provided at a position on the foil tab T corresponding to a first region adjacent to the outer periphery of the electrode assembly C, and a second pressure block 22 provided at a position on the foil tab T corresponding to a second region adjacent to the winding center of the electrode assembly C.

[0088] The step (S1) may be performed by a forming jig 20 in which the pressing surface of the first pressing block 21 and the pressing surface of the second pressing block 22 have the same inclination. The step (S1) may be performed by a forming jig 20 in which the first pressing block 21 and the second pressing block 22 are configured to be independently movable in a direction parallel to the winding axis of the electrode assembly C.

[0089] The step (S1) may include a step of (S11) performing a primary press by moving the first pressurizing block 21 and the second pressurizing block 22 toward the foil tab T while the pressurizing surface of the first pressurizing block 21 and the pressurizing surface of the second pressurizing block 22 are on the same plane, and a step of (S12) performing a secondary press by moving the second pressurizing block 22 toward the foil tab T while the position of the first pressurizing block 21 is maintained after the step (S21). In this case, the lowermost end 22a of the second pressurizing block after the steps (S11) and (S12) may be positioned at the same height as the lowermost end 21a of the first pressurizing block 21 or may be positioned higher. The step (S1) may be performed by rotating the first pressurizing block 21 and the second pressurizing block 22 together or independently on the same axis as the winding shaft.

[0090] The step (S1) may be performed by a forming jig 30 including a first pressing block 31 provided at a position on the foil tab T corresponding to a first region adjacent to the outer periphery of the electrode assembly C, a third pressing block 33 provided at a position on the foil tab T corresponding to a third region adjacent to the winding center of the electrode assembly C, and a second pressing block 32 provided at a region on the foil tab T corresponding to a second region located between the first and third regions. The step (S1) may be performed by a forming jig 20 in which the pressing surface of the first pressing block 31, the pressing surface of the second pressing block 32, and the pressing surface of the third pressing block 33 have substantially the same inclination. In this case, the step (S1) may include the steps of: (S11) performing a primary press by moving the first pressurizing block 31, the second pressurizing block 32, and the third pressurizing block 33 toward the foil tab T while their pressurizing surfaces are in the same plane; (S12) performing a secondary press by moving the second pressurizing block 32 and the third pressurizing block 33 toward the foil tab T while the first pressurizing block 31 is maintained in position after the step (S11) while their pressurizing surfaces are in the same plane; and (S13) performing a tertiary press by moving the third pressurizing block 33 toward the foil tab T while the first pressurizing block 31 and the second pressurizing block 32 are maintained in position after the step (S12). The step (S1) may be performed using a pair of the forming jigs 20 disposed at both ends of the electrode assembly C on the opposite sides along the winding axis of the electrode assembly C. That is, step (S1) may be a step of performing forming on each of the first foil tab (first polarity) and the second foil tab (second polarity) provided at both ends in the height direction (direction parallel to the Z-axis) of the electrode assembly C. In this case, step (S1) may be performed by rotating the pair of forming jigs 20 in opposite directions based on the same axis as the winding axis of the electrode assembly C. The forming of the first foil tab and the forming of the second foil tab may be performed simultaneously or with a time lag.

[0091] As described above, according to the foil tab forming apparatus and / or the foil tab forming method of the present invention, the foil tab T of the electrode assembly C is divided into a plurality of regions approximately along the radial direction of the electrode assembly C, and each region is individually and intensively formed, thereby enabling efficient and accurate forming. Furthermore, according to the foil tab forming apparatus and / or the foil tab forming method of the present invention, a method in which rotation and pressure are performed simultaneously can be applied, thereby enabling smoother forming.

[0092] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and various modifications and variations can be made by those having ordinary skill in the art to which the present invention pertains within the scope of the technical spirit of the present invention and the equivalent scope of the claims. [Explanation of symbols]

[0093] C Electrode assembly T Foil Tab P Current collector plate 10 Preforming jig 11 Shutter Block 12 Shutter Frame 14 Slots 16 Guide member 20, 30 Forming jig 21, 31 First pressure block 22, 32 Second pressure block 33 Third pressure block

Claims

1. 1. A foil tab forming apparatus for forming a foil tab of an electrode assembly having an outer periphery and a winding center defining a winding axis, comprising: a forming jig configured to move along a direction parallel to a winding axis of the electrode assembly to press the foil tab; a preforming jig configured to press and bend the foil tab while moving in a direction from an outer periphery of the electrode assembly toward a winding center of the electrode assembly; Including, The forming jig is configured to pressurize the foil tab that has been subjected to the primary bending by the preforming jig; The preforming jig is provided with a plurality of shutter blocks arranged around an outer periphery of the electrode assembly and moving in a direction toward a winding center of the electrode assembly to bend the foil tab.

2. The shutter block includes: The foil tab forming apparatus according to claim 1 , wherein a surface facing the foil tab is inclined upward in a direction from an outer periphery of the electrode assembly toward the winding center.

3. The forming jig is 3. The foil tab forming apparatus of claim 1 or 2, having a width equal to or greater than a diameter of the electrode assembly.

4. The forming jig is The foil tab forming apparatus according to claim 1 , configured to rotate coaxially with a winding axis of the electrode assembly.

5. The forming jig is The foil tab forming apparatus of claim 4 configured to rotate in a clockwise or counterclockwise direction.

6. The forming jig is configured to both press and rotate the foil tab; 6. The foil tab forming apparatus according to claim 4 or 5.

7. The forming jig is The foil tab forming apparatus according to claim 1 , wherein a surface facing the foil tab is inclined upward in a direction from an outer periphery of the electrode assembly toward the winding center.

8. The forming jig is a first pressure block provided in the foil tab at a position corresponding to a first region adjacent to an outer periphery of the electrode assembly; 8. The foil tab forming apparatus according to claim 7, further comprising: a second pressure block provided at a position corresponding to a second region of the foil tab adjacent to a winding center of the electrode assembly.

9. 9. The foil tab forming apparatus of claim 8, wherein a pressure surface of the first pressure block and a pressure surface of the second pressure block have the same inclination and define a surface of the forming jig that faces the foil tab.

10. The first pressure block and the second pressure block are The foil tab forming apparatus according to claim 8 or 9, wherein the electrode assembly is configured to be independently movable along a direction parallel to a winding axis of the electrode assembly.

11. The forming jig is 10. The foil tab forming apparatus according to claim 9, wherein the first and second pressurizing blocks are configured to move together toward the foil tab while the pressurizing surfaces of the first and second pressurizing blocks are in the same plane to perform a primary pressurization, and then the second pressurizing block is configured to move further toward the foil tab while the position of the first pressurizing block is maintained as it is to perform a secondary pressurization.

12. The forming jig is 12. The foil tab forming apparatus according to claim 11, wherein after the primary and secondary pressurization are completed, a lowermost end of the second pressurizing block is configured to be positioned at the same height as or higher than a lowermost end of the first pressurizing block.

13. The first pressure block and the second pressure block are The foil tab forming apparatus of claim 8 , configured to rotate together or independently with respect to the same axis as the winding shaft.

14. The forming jig is a first pressure block provided in the foil tab at a position corresponding to a first region adjacent to an outer periphery of the electrode assembly; a third pressing block provided in the foil tab at a position corresponding to a third region adjacent to a winding center portion of the electrode assembly; 8. The foil tab forming apparatus according to claim 7, further comprising: a second pressure block provided at a position corresponding to a second region of the foil tab, the second region being located between the first region and the third region.

15. The forming jig is The foil tab forming apparatus according to claim 1 , provided as a pair of forming jigs arranged at opposite ends of the electrode assembly along a winding axis of the electrode assembly.

16. The pair of forming jigs include: The foil tab forming apparatus according to claim 15 , wherein the electrode assemblies rotate in opposite directions about the same axis as the winding shaft of the electrode assemblies.

17. The preforming jig is The foil tab forming apparatus of claim 1 , provided as a pair of preforming jigs disposed at opposite ends of the electrode assembly along a winding axis of the electrode assembly.

18. 1. A foil tab forming method for forming a foil tab of an electrode assembly having an outer periphery and a winding center defining a winding axis, comprising: (S1) bending the foil tab by applying pressure to the foil tab along a direction parallel to a winding axis of the electrode assembly using a forming jig; (S0) before the step (S1), pressing and bending the foil tab in a direction from an outer periphery of the electrode assembly toward a winding center of the electrode assembly using a preforming jig; Including, The step (S1) is a step of further bending the foil tab by applying pressure to the foil tab preformed in the step (S0), The foil tab forming method, wherein step (S0) is performed using the preforming jig including a plurality of shutter blocks disposed around an outer periphery of the electrode assembly and moving along a direction toward a winding center of the electrode assembly to bend the foil tab.

19. The step (S0) includes:

20. The method of claim 18, wherein the method is performed using a preforming jig including a plurality of shutter blocks, the surface facing the foil tab being inclined upward in a direction from the outer periphery of the electrode assembly toward the winding center.

20. The step (S1) 20. The foil tab forming method according to claim 18 or 19, wherein the method is performed using a forming jig having a width equal to or larger than a diameter of the electrode assembly.

21. The step (S1) The foil tab forming method according to any one of claims 18 to 20, which is performed using a forming jig configured to rotate coaxially with a winding axis of the electrode assembly.

22. The step (S1) 22. The method of any one of claims 18 to 21, performed using a forming jig configured to both compress and rotate the foil tab.

23. In the step (S1), 23. The method of claim 22, wherein the forming jig rotates clockwise to cause the foil tabs to be oriented clockwise.

24. In the step (S1), 23. The method of claim 22, wherein the forming jig rotates counterclockwise to cause the foil tabs to be oriented counterclockwise.

25. The step (S1) 25. The method of claim 18, wherein the forming is performed using a forming jig having a surface facing the foil tab that is inclined upward in a direction from the outer periphery of the electrode assembly toward the winding center.

26. The step (S1) 26. The method of claim 25, wherein the forming jig includes: a first pressure block provided at a position on the foil tab that corresponds relatively to a first region adjacent to an outer periphery of the electrode assembly; and a second pressure block provided at a position on the foil tab that corresponds relatively to a second region adjacent to a winding center of the electrode assembly.

27. The step (S1) 27. The foil tab forming method according to claim 26, wherein the forming is performed by a forming jig in which the pressing surface of the first pressing block and the pressing surface of the second pressing block have the same inclination.

28. The step (S1) The foil tab forming method according to claim 26, wherein the first and second pressing blocks are formed by a forming jig configured to be independently movable along a direction parallel to a winding axis of the electrode assembly.

29. The step (S1) (S11) performing a primary pressure application by moving the pressing surface of the first pressing block and the pressing surface of the second pressing block toward the foil tab while the pressing surfaces are in the same plane; (S12) after the step (S11), the second pressurizing block is further moved toward the foil tab while maintaining the position of the first pressurizing block, thereby performing a secondary pressurization.

30. 30. The method of claim 29, wherein after steps (S11) and (S12), a lowermost end of the second pressing block is positioned at the same height as or higher than a lowermost end of the first pressing block.

31. The step (S1) The foil tab forming method according to claim 26, wherein the first and second pressurizing blocks rotate together or independently about the same axis as the winding shaft.

32. The step (S1) 26. The method of claim 25, wherein the forming jig is performed using a forming jig including: a first pressure block provided in the foil tab at a position corresponding to a first region adjacent to an outer periphery of the electrode assembly; a third pressure block provided in the foil tab at a position corresponding to a third region adjacent to a winding center of the electrode assembly; and a second pressure block provided in the foil tab at a region corresponding to a second region located between the first and third regions.

33. The step (S1) The foil tab forming method according to claim 32, wherein the forming jig is used in which the pressing surface of the first pressing block, the pressing surface of the second pressing block, and the pressing surface of the third pressing block have the same inclination.

34. The step (S1) (S11) performing a primary pressurization by moving the foil tabs toward each other while the pressing surface of the first pressing block, the pressing surface of the second pressing block, and the pressing surface of the third pressing block are in the same plane; (S12) after the step (S11), the position of the first pressurizing block is maintained as it is, and the second pressurizing block and the third pressurizing block move toward the foil tab with their pressurizing surfaces being on the same plane to perform a secondary pressurization; (S13) after the step (S12), the third pressurizing block moves toward the foil tab while maintaining the positions of the first and second pressurizing blocks, thereby performing a tertiary pressurization.

35. The step (S1) 35. The foil tab forming method according to claim 18, wherein the method is performed using a pair of forming jigs disposed at opposite ends of the electrode assembly along a winding axis of the electrode assembly.

36. The step (S1) The foil tab forming method according to claim 35, wherein the pair of forming jigs are rotated in opposite directions relative to an axis coaxial with a winding axis of the electrode assembly.

37. The step (S0) comprises:

20. The foil tab forming method of claim 18, performed using a pair of the preforming jigs disposed at opposite ends of the electrode assembly along a winding axis of the electrode assembly.

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