Foil tab forming apparatus and method

Abstract

The present invention provides a foil tab forming apparatus and method. The foil tab forming apparatus is for forming an electrode tab exposed at one end of an electrode assembly in which a first electrode, a separator, and a second electrode are stacked and wound around a winding axis, and is characterized by comprising: a base unit having a flat surface; a pressing unit protruding from the flat surface of the base unit in the winding axis direction and configured to divide the electrode tab into a plurality of regions; and a plurality of forming units provided to correspond to the plurality of divided regions and configured to bend the electrode tab radially inward around the winding axis in each of the divided regions.

Description

Foil tab forming device and method

[0001] The present invention relates to a foil tab forming apparatus and method, and more specifically, to a foil tab forming apparatus and method for an improved forming method. This application is a priority application for Korean Patent Application No. 10-2024-0191685 filed on December 19, 2024, and all contents disclosed in the specification and drawings of said application are incorporated by reference into this application.

[0002] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product groups, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by electric sources. These secondary batteries are attracting attention as a new energy source for enhancing eco-friendliness and energy efficiency, not only for the primary advantage of drastically reducing the use of fossil fuels but also because they generate no by-products from energy use.

[0003] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, or unit foil tab forming devices, is approximately 2.5V to 4.5V. Therefore, if a higher output voltage is required, multiple foil tab forming devices are connected in series to form a battery pack. Additionally, depending on the charge / discharge capacity required for the battery pack, multiple foil tab forming devices are connected in parallel to form a battery pack. Accordingly, the number of foil tab forming devices included in the battery pack can be varied depending on the required output voltage or charge / discharge capacity.

[0004] Meanwhile, conventional cylindrical secondary batteries adopted a structure in which tabs were welded to the electrode assembly to electrically connect the electrodes and external terminals. Although tabs were primarily manufactured from separate metal components and designed to be welded to the electrode assembly, this structure had the potential to affect battery performance due to increased contact resistance and non-uniform current density between the tab and the electrode assembly. Furthermore, there were technical limitations in the design and manufacturing methods of the tabs in meeting the demand for increased battery capacity.

[0005] To overcome these limitations, a design has been proposed that utilizes the non-existent portions of the anode and cathode themselves as electrode tabs. Using the non-existent portions as electrode tabs optimizes the current path, reduces contact resistance, and further improves battery capacity and energy efficiency. However, when utilizing the non-existent portions as electrode tabs, uniform alignment and fixation of the electrode tabs are critical. In particular, the importance of research on forming technology, which stably bends and uniformly presses the electrode tabs during the assembly process, is emerging.

[0006] This forming technology is an important process that directly affects the arrangement of electrode tabs and battery performance. If the electrode tabs are not bent into a uniform shape, it can lead not only to an increase in the defect rate during the assembly process but also to overheating and reduced lifespan of the secondary battery. In addition, a method is required to ensure that the electrode tabs do not obstruct the reform hole into which the welding rod is inserted during the assembly process.

[0007] Therefore, improved forming technology and design are required to smoothly bend electrode tabs in order to optimize the current path, maximize battery performance, and increase the efficiency of the assembly process.

[0008] Accordingly, the technical problem to be solved by the present invention is to provide a foil tab forming apparatus and method for improving the performance of a battery cell.

[0009] In addition, the invention provides a foil tab forming device and method capable of smoothly bending the foil tab.

[0010] In addition, the invention provides a foil tab forming device and method in which the forming thickness of the foil tab is uniform throughout.

[0011] In addition, the invention provides a foil tab forming device and method that does not obstruct the reform hole required in the welding process during forming.

[0012] However, the technical problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by those skilled in the art from the description of the invention below.

[0013] To solve the above objective, the present invention provides a foil tab forming device for forming an electrode tab exposed at one end of an electrode assembly wound around a winding axis by stacking a first electrode, a separator, and a second electrode, comprising: a base portion having a flat surface; a pressurizing portion protruding in the direction of the winding axis from the flat surface of the base portion and configured to divide the electrode tab into a plurality of regions; and a plurality of forming portions provided in a plurality corresponding to the divided regions and configured to bend the electrode tab radially inward around the winding axis within each of the divided regions.

[0014] For example, the above-mentioned pressurizing part may have a radial structure based on the center point of the above-mentioned pressurizing part.

[0015] For example, the above-mentioned pressurizing member may have a length longer than the length of the electrode tab with respect to the winding axis direction.

[0016] For example, each of the plurality of forming parts includes a forming jig, and the forming jig may be configured to move toward the center point of the pressing part.

[0017] For example, each of the plurality of forming parts includes a connecting part provided on the flat surface of the base part, and the forming jig may be coupled to the connecting part and configured to move along the longitudinal direction of the connecting part.

[0018] For example, the forming jig may have a length longer than the length of the electrode tab with respect to the winding axis direction.

[0019] For example, the above-mentioned pressurizing part may be positioned between the above-mentioned connecting parts that are adjacent to each other.

[0020] For example, a plurality of the above-mentioned connecting parts may form a symmetrical structure with respect to the center point of the pressurizing part.

[0021] For example, a plurality of the above-mentioned connecting parts may each be arranged at a predetermined distance from the center point of the pressurizing part.

[0022] For example, the foil tab forming device may include an insertion part configured to be inserted to a predetermined depth into the center hole of the electrode assembly.

[0023] For example, the insert portion may protrude further from the base portion than the pressing portion with respect to the winding axis direction.

[0024] For example, the above-mentioned pressurizing part may have a length longer than the length of the electrode assembly in the radial direction.

[0025] For example, the above-mentioned pressurizing member may be configured to press the electrode tab in the winding axis direction as the insertion member is inserted into the center hole of the electrode assembly.

[0026] For example, the plurality of forming parts may each be configured to bend the electrode tab radially inward from the outer surface of the electrode assembly while the electrode tab is pressed in the direction of the winding axis by the pressing part.

[0027] For example, the pressurizing part and the forming part may be configured to surround the electrode tab in each of the partitioned plurality of regions when the insertion part is inserted into the center hole.

[0028] In addition, to solve the above objective, the present invention provides a foil tab forming method for forming an electrode tab exposed at one end of an electrode assembly wound around a winding axis by laminating a first electrode, a separator, and a second electrode, the method comprising: a first step of preparing the electrode assembly; a second step of aligning the center hole of the electrode assembly and the center of the pressure part in a line; a third step of applying pressure to the electrode tab along the winding axis direction with the pressure part to divide the electrode tab into a plurality of regions; and a fourth step of moving each forming part provided in each of the divided regions toward the center of the pressure part to bend the electrode tab radially inward.

[0029] For example, the third step above may insert an insertion part configured to be inserted to a certain depth into the center hole of the electrode assembly, and at the same time pressurize the electrode tab by the pressurizing part.

[0030] The foil tab forming device and method according to various embodiments of the present invention have the effect of being able to smoothly bend the foil tab.

[0031] In addition, the foil tab forming device and method according to various embodiments have the effect that the forming thickness of the electrode tab of the electrode assembly is uniform throughout.

[0032] In addition, the foil tab forming device and method according to various embodiments have the effect of not obscuring the reform hole required in the welding process during forming.

[0033] However, the effects obtainable through the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by those skilled in the art from the description of the invention below.

[0034] FIG. 1 is a drawing for explaining each configuration of a pre-winding electrode assembly according to one embodiment of the present invention.

[0035] Figure 2 is a schematic diagram showing the stacked structure of each component of the electrode assembly of Figure 1.

[0036] Figure 3 is a schematic diagram showing the jelly-roll type electrode assembly of Figure 1.

[0037] Figure 4 is a schematic diagram showing the electrode tab of the electrode assembly of Figure 3.

[0038] FIG. 5 is a schematic diagram showing an electrode tab according to another embodiment of the electrode assembly of FIG. 3.

[0039] FIG. 6 is a schematic diagram showing a foil tab forming device according to one embodiment of the present invention.

[0040] Fig. 7 is a front view of the foil tab forming device of Fig. 6.

[0041] Figure 8 is a drawing illustrating the appearance of the electrode assembly of Figure 3 being pressed by the pressing part of the foil tab forming device of Figure 6.

[0042] Figure 9 is a cross-sectional view along the AA' cutting line of Figure 8.

[0043] Figure 10 is a drawing illustrating the appearance of the electrode tab area of ​​Figure 4 being divided into multiple sections.

[0044] FIG. 11 is a drawing to explain the appearance of the electrode tab area of ​​FIG. 5 being divided into multiple sections.

[0045] FIG. 12 is a drawing to explain the appearance of the electrode assembly of FIG. 3 being pressed by the forming part of the foil tab forming device of FIG. 6.

[0046] FIG. 13 is a drawing illustrating the appearance of the electrode tab of FIG. 4 being bent radially inward.

[0047] FIG. 14 is a drawing illustrating the appearance of the electrode tab of FIG. 5 being bent radially inward.

[0048] FIG. 15 is a flowchart of a foil tab forming method according to one embodiment of the present invention.

[0049] FIG. 16 is a flowchart of a foil tab forming method according to another embodiment of the present invention.

[0050] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, 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 in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0051] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0052] In addition, the present invention includes various embodiments. For each embodiment, redundant descriptions of substantially identical or similar configurations are omitted, and the focus is on the differences.

[0053] Additionally, to aid in understanding the invention, the attached drawings are not drawn to actual scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to identical components in different embodiments.

[0054] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may also be the second component.

[0055] Throughout the specification, unless specifically stated otherwise, each component may be singular or plural.

[0056] In the following, the statement that any configuration is placed on the "upper (or lower)" of a component or on the "upper (or lower)" of a component may mean not only that any configuration is placed in contact with the upper (or lower) surface of said component, but also that another configuration may be interposed between said component and any configuration placed on (or below) said component.

[0057] In addition, where it is stated that one component is "connected," "combined," or "connected" to another component, it should be understood that while the components may be directly connected or connected to each other, another component may be "interposed" between each component, or each component may be "connected," "combined," or "connected" through another component.

[0058] Singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "composed of" or "comprising" should not be interpreted as necessarily including all of the various components or steps described in the specification, and should be interpreted as meaning that some of the components or steps may be omitted or additional components or steps may be included.

[0059] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back may be used in this specification, these terms are used merely for convenience of explanation and may vary depending on the position or arrangement, rotation, or position of the observer, as is obvious to those skilled in the art of this invention.

[0060] The present invention may be implemented in the following embodiments, each independently. Furthermore, the present invention may be implemented in combination of two or more of the following embodiments. Each of the following embodiments may not only be implemented independently but may also be freely combined with one another.

[0061]

[0062] FIG. 1 is a drawing for explaining each component of a pre-winding electrode assembly (20) according to one embodiment of the present invention, FIG. 2 is a drawing schematically showing the stacked structure of each component of the electrode assembly (20) of FIG. 1, FIG. 3 is a drawing schematically showing the jelly-roll type electrode assembly (20) of FIG. 1, FIG. 4 is a drawing schematically showing the electrode tab (27) of the electrode assembly (20) of FIG. 3, and FIG. 5 is a drawing schematically showing the electrode tab according to another embodiment of the electrode assembly of FIG. 3.

[0063] First, with reference to FIGS. 1 and 2, embodiments of an electrode assembly (20) in which the foil tab forming device (100) according to the present invention can be used will be described. However, the foil tab forming device (100) of the present invention is not necessarily required to be applied only to the electrode assembly (20) of the structure described below.

[0064] An electrode assembly (20) in which the foil tab forming device (100) according to the present invention can be used may be configured such that the first electrode (21) and the second electrode (22) and the separator (28) interposed between them are wound around a winding axis.

[0065] The electrode assembly (20) after the winding is completed may be in the form of a jelly-roll. When viewed from the top or bottom in the direction of the winding axis of the electrode assembly (20), the outer shape of the electrode assembly (20) along the circumferential direction may be circular. However, the structure of the electrode assembly (20) is not limited by the embodiment and may have a winding structure well known in the art.

[0066] The first electrode (21), the second electrode (22), and the separator (28) may each have a predetermined width along the winding axis direction and be formed to extend a predetermined length along the winding direction. The first electrode (21) may be an anode plate, and the second electrode (22) may be a cathode plate. Of course, the opposite may also be true.

[0067] The first electrode (21) and the second electrode (22) may be manufactured in the form of a sheet. The first electrode (21) and the second electrode (22) may be configured such that an active material layer (25) is applied to at least a portion of the surface of the metal foil (23). The first electrode (21) and the second electrode (22) may have a retaining portion (24) region where the active material layer (25) is applied and a non-retaining portion (26) region where the active material layer (25) is not applied.

[0068] The uncoated portion (26) may be exposed to the outside of the separator (28) while forming a plurality of winding turns based on the winding axis of the electrode assembly (20). That is, the positive plate and the negative plate may each include an uncoated portion (26) in which the active material is not coated at the long side end in the direction of the winding axis. In addition, the uncoated portions (26) of the first electrode (21) and the second electrode (22) may be configured to face opposite directions in the direction of the winding axis. The uncoated portion (26) of the first electrode (21) may be housed inside the battery can (10) such that it is located at one end in the direction of the winding axis and the uncoated portion (26) of the second electrode (22) is located at the other end in the direction of the winding axis.

[0069] The unwound portions (26) of the first electrode (21) and the second electrode (22) can be formed at one end of the winding axis direction, each having a predetermined width along the winding axis direction and extending to a predetermined length along the winding direction.

[0070] At this time, the unwound portions (26) of the first electrode (21) and the second electrode (22), which are positioned at both ends of the winding axis direction of the electrode assembly (20) to which the foil tab forming device (100) of the present embodiment can be used, may have a shape in which the height protruding in the winding axis direction is at least partially or entirely the same. Of course, the unwound portions (26) are not limited to such a shape and may have a shape in which the height protruding in the winding axis direction increases stepwise or gradually along the winding axis direction.

[0071] Here, the positive active material coated on the positive plate and the negative active material coated on the negative plate may be used without limitation as long as they are active materials known in the art.

[0072] Also, the separator (28) may be a porous polymer film, for example, a porous polymer film made of a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, an ethylene / methacrylate copolymer, etc., used alone or in a laminated form. As another example, the separator may be a conventional porous nonwoven fabric, for example, a nonwoven fabric made of high-melting-point glass fibers, polyethylene terephthalate fibers, etc.

[0073] At least one surface of the separator (28) may include a coating layer of inorganic particles. Additionally, it is possible for the separator (28) itself to be composed of a coating layer of inorganic particles. The particles constituting the coating layer may have a structure combined with a binder such that interstitial volume exists between adjacent particles.

[0074] This non-removable portion (26) can itself function as an electrode tab (27).

[0075] Referring to FIGS. 3 and 4, the electrode tabs (27) of the first electrode (21) and the second electrode (22) positioned at both ends of the winding axis direction of the electrode assembly (20) can each be configured to have the same width along the winding axis direction.

[0076] The electrode tabs (27) of the first electrode (21) and the second electrode (22), which are positioned at both ends of the winding axis direction of the electrode assembly (20) to which the foil tab forming device (100) of the present embodiment can be used, may be configured to have the same height protruding in the winding axis direction from the core to the outer circumference.

[0077] However, the electrode assembly (20) to which the foil tab forming device (100) of the present embodiment can be used is not limited to the form shown in the present specification and may be designed to have various forms of electrode tabs (27). For example, referring to FIG. 5, the electrode tabs (27) of the first electrode (21) and the second electrode (22) disposed at both ends of the electrode assembly (20) in the direction of the winding axis may each be omitted in a predetermined section near the core of the electrode assembly (20). In addition, the electrode tabs (27) of the first electrode (21) and the second electrode (22) disposed at both ends of the electrode assembly (20) in the direction of the winding axis may have a form in which the height protruding in the direction of the winding axis from the core towards the outer circumference gradually or stepwise increases.

[0078] The electrode tabs (27) of the first electrode (21) and the second electrode (22), which are positioned at both ends of the winding axis direction of the electrode assembly (20) to which the foil tab forming device (100) of the present embodiment can be used, may have the shape of a pull tab that is not notched as a whole.

[0079] Additionally, in another embodiment, the electrode tabs (27) of the first electrode (21) and the second electrode (22) disposed at both ends in the winding axis direction of the electrode assembly (20) may have the shape of notched tabs. Within the section where the notched tab of the first electrode (21) and the notched tab of the second electrode (22) are provided, the electrode tabs (27) may have the same height protruding in the winding axis direction.

[0080] This electrode assembly (20) requires a processing process of bending electrode tabs (27), which are positioned at both ends in the winding axis direction with respect to the center hole (H1), inwardly in the radial direction.

[0081] A foil tab forming device (100) according to one embodiment of the present invention is a processing device designed to uniformly bend the electrode tab (27) of an electrode assembly (20) radially inward for such a processing process. The foil tab forming device (100) will be described in detail below.

[0082]

[0083] FIG. 6 is a schematic diagram showing a foil tab forming device (100) according to one embodiment of the present invention, and FIG. 7 is a front view of the foil tab forming device (100) of FIG. 6.

[0084] Referring to FIGS. 6 and 7, a foil tab forming device (100) according to one embodiment of the present invention may largely comprise a base part (110), a pressurizing part (120), and a forming part (130).

[0085] The base portion (110) is a support structure for the foil tab forming device (100) and is designed to stably support and position each component and part of the foil tab forming device (100). The base portion (110) may be formed of a material having rigidity and durability and may include a flat surface so that the components are mounted without shaking.

[0086] Additionally, the base portion (110) can improve the processing accuracy of the electrode tab (27) by enabling precise position adjustment during the assembly and operation of other components. For example, the base portion (110) may include a coupling groove, a fixing pin, or a screw coupling portion in a specific area so that the pressing portion (120) and the forming portion (130) can be accurately installed.

[0087] The pressurizing part (120) may be configured to protrude in the direction of the winding axis from the flat surface of the base part (110) to divide the electrode tab (27) into a plurality of regions. This allows the electrode tabs in each region to be uniformly aligned and smoothly bent during the subsequent forming process.

[0088] Additionally, the forming section (130) is provided in multiple units corresponding to a plurality of partitioned areas and can be configured to bend the electrode tab (27) within each partitioned area radially inward around the winding axis. By doing so, the electrode tab of each area can be bent in a certain direction by each forming section (130), thereby allowing for uniform forming overall.

[0089] That is, the forming part (130), designed to fit each section of the pressurizing part (120), precisely bends the electrode tab (27) in a uniform direction so that the height of the entire electrode tab (27) can be maintained at a constant level, and thereby the total height of the entire electrode assembly (20) can be maintained uniformly within the designed specifications.

[0090] Accordingly, the foil tab forming device (100) according to one embodiment of the present invention can perform the arrangement and bending process of the electrode tab (27) uniformly and precisely through the interaction between the pressurizing part (120) and the forming part (130), thereby simultaneously improving the manufacturing efficiency and performance of the battery cell.

[0091]

[0092] Below, the specific structure of the pressurizing part (120) and the forming part (130) will be described.

[0093] The pressurizing part (120) can be designed in various shapes to divide the electrode tab (27) into multiple regions.

[0094] As an example, the pressurizing part (120) may be formed as a single integral protruding structure. In this case, the pressurizing part (120) has a structure that protrudes continuously from the flat surface of the base part (110) and may be composed of continuous or spaced protruding lines to define each area. Such an integral structure of the pressurizing part (120) may be advantageous for simplifying the manufacturing process and improving structural rigidity.

[0095] As an example, the pressurizing part (120) may be formed with a plurality of independent protruding structures. In this case, the pressurizing part (120) may have the form of ribs or partition walls arranged at regular intervals. Each of these protruding structures of the pressurizing part (120) may be arbitrarily modified according to the desired design process.

[0096] Whether the pressure member (120) is a single integrated type or a plurality of protruding structures, each design can align the arrangement of the electrode tabs (27) and provide uniform pressure during the bending process, thereby minimizing deformation of the electrode tabs (27) and improving the precision of the forming process.

[0097] Additionally, the pressurizing part (120) has an appropriate height and thickness to effectively fix the electrode tab (27) and can be implemented in various shapes depending on the size and arrangement of the electrode tab (27). For example, the pressurizing part (120) may have a straight, curved, or polygonal cross-section.

[0098] As an example, the pressurizing part (120) may be designed with a radial structure based on the center point (C) of the pressurizing part (120). This radial structure can uniformly divide the electrode tab (27) in the direction of the outer surface based on the center hole (H1). For example, the pressurizing part (120) may be formed in a cross shape. In this case, the pressurizing part (120) has a structure protruding in two axial directions that are orthogonal to each other based on the center point (C), and can divide the electrode tab (27) into four symmetrical regions. This cross shape is structurally simple yet can align the position of the electrode tab (27) and uniformly divide the region. In addition, the cross shape can increase the efficiency of the manufacturing process and ensure that the electrode tab in each region is accurately bent during the subsequent forming process.

[0099] The radial structure of the pressurizing part (120) can be implemented in various forms along multiple axes in addition to a cross shape. For example, a structure forming a triangular, square, or polygonal radial section is also possible, and this can be applied according to the arrangement and size of the electrode tabs (27) and battery design requirements. The radial structure can uniformly support the electrode tabs (27) in all directions and maintain alignment with the winding axis of the electrode assembly (20).

[0100] The pressurizing unit (120) is not limited to simply partitioning the electrode tabs (27), but can also provide a predetermined pressure to ensure that the electrode tabs (27) within each partition maintain a uniform spacing and arrangement.

[0101] The pressurizing part (120) can be designed in a modular manner so that its position and size can be adjusted by considering the arrangement and placement state of the electrode tabs (27). This allows for flexible adaptation to various electrode assembly (20) designs and can be applied according to the type and specifications of the battery cell.

[0102] The pressure member (120) may be designed to have a length (L2) longer than the length (L1) of the electrode tab (27) with respect to the winding axis direction. This allows for stable support and uniform pressure to be provided over the entire length of the electrode tab (27) when the electrode tab (27) comes into contact with the pressure member (120). If necessary, the pressure member (120) may be adjusted to have a length (L2) that is similar to or slightly longer than the length (L1) of the electrode tab (27), which allows the electrode tab (27) to be precisely aligned with the pressure member (120).

[0103] The forming section (130) may be provided in multiple units. Each of these multiple forming sections (130) may include a forming jig (131).

[0104] The forming jig (131) can be designed to move toward the center point (C) of the pressurizing part (120) and can operate to uniformly bend the electrode tab (27) with respect to the winding axis. This forming jig (131) can provide the structural stability and operability necessary to increase the bending angle and precision of the electrode tab (27).

[0105] The forming jig (131) can be designed in a specific shape to suit the structure of the pressurizing part (120), for example, the radial structure of the pressurizing part (120). For example, it can be formed in an arc shape having a constant curvature to be joined along the angle of the radially arranged pressurizing part (120).

[0106] Each of the multiple forming sections (130) may include a connecting section (132) installed on the flat surface of the base section (110). The connecting section (132) serves to connect the forming jig (131) to the base section (110) and can perform the function of guiding the forming jig (131) to move along an accurate trajectory.

[0107] The connecting portion (132) has a structure that extends in the longitudinal direction and can be configured so that the forming jig (131) can move toward the center point (C) along the longitudinal direction of the connecting portion (132). For example, the connecting portion (132) may be provided in a rail shape on which the forming jig (131) can be mounted to guide the movement path of the forming jig (131).

[0108] The connecting part (132) can be fixedly installed on the flat surface of the base part (110) and may have a structure that extends in the longitudinal direction so that the forming jig (131) can move along a straight or curved path toward the center point (C). The connecting part (132) guides the movement of the forming jig (131) to be smooth and can provide high precision so that the forming jig (131) operates properly at an accurate position.

[0109] The connecting part (132) may include various additional structures to fix the position of the forming jig (131) or control its movement, in addition to the rail. For example, the connecting part may include a moving element such as a slider to allow the forming jig (131) to move smoothly and stably. Additionally, it may be equipped with a stopper or a locking device to accurately align the position of the forming jig (131) with the pressing part (120).

[0110] Furthermore, the forming jig (131) and the connecting part (132) may be designed to support automated process control as needed. For example, the connecting part (132) may include a motor-driven rail system. Additionally, the forming jig (131) may be configured to include a sensor to detect the position or shape of the electrode tab (27) of the pressure part (120) or the electrode assembly (20) and to automatically move to that position. This design can ensure high productivity even in mass production processes by maximizing process speed and accuracy.

[0111] The forming jig (131) can maximize the stability and precision of the forming process by moving while maintaining a constant force and directionality while combined with the connecting part (132). This design ensures that each forming jig (131) can uniformly bend the electrode tab (27) within the partitioned area.

[0112] The forming jig (131) can be designed to have a length (L3) longer than the length (L1) of the electrode tab (27) with respect to the winding axis direction. This provides a supporting force so that the electrode tab (27) can be stably bent when in contact with the forming jig (131). For example, the forming jig (131) can be coupled to or mounted on the connecting part (132), and the connecting part (132) can perform the role of guiding the movement of the forming jig. At this time, the forming jig (131) can uniformly bend the electrode tab (27) by utilizing the remaining length excluding the length of the connecting part (132). Through this, the forming jig (131) can perform precise bending operations over the entire length of the electrode tab (27) while maintaining a stable operating environment through coupling with the connecting part (132).

[0113] The forming jig (131) can be designed to have a length (L3) equal to the length (L2) of the pressurizing part (120) with respect to the winding axis direction. This allows the forming jig (131) to have integrality when combined with the pressurizing part (120) and enables each component to operate harmoniously with each other during the forming process. In this way, the forming jig (131), which has integrality when combined with the pressurizing part (120), can maximize the uniformity of the electrode tab (27) arrangement and the forming precision by ensuring that the bending area of ​​the electrode tab (27) and the partitioned area of ​​the pressurizing part (120) match exactly.

[0114] The pressurizing part (120) can be positioned between adjacent connecting parts (132). By doing so, the pressurizing part (120) can maintain its position stably and efficiently perform the forming process of the electrode tab (27) through interaction with the connecting part (132).

[0115] Such multiple connecting parts (132) can form a symmetrical structure with respect to the center point (C) of the pressing part (120). This symmetrical structure can be used to optimize the movement path and alignment of the forming jig (131) by ensuring that each connecting part (132) maintains the same spacing and position. In particular, this symmetrical structure minimizes asymmetrical forces or deformations that may occur during the forming process and allows the electrode tabs (27) to be uniformly arranged and bent.

[0116] In this way, by positioning the pressurizing part (120) between the connecting part (132), each connecting part (132) can perform the role of guiding the forming jig (131) to stably connect with the pressurizing part (120). In addition, since the connecting part (132) is arranged symmetrically with respect to the center point (C) of the pressurizing part (120), it provides harmony and stability to the overall structure and can support multiple forming jigs (131) to operate at equal intervals. This can contribute to improving the precision and productivity of the forming process.

[0117] A plurality of connecting parts (132) may be arranged at a predetermined distance (L4) from the center point (C) of the pressing part (120). This arrangement allows the connecting parts (132) to smoothly guide the movement of the forming jig (131) while preventing excessive pressure from being applied to the electrode tab (27) during the forming process. This prevents excessive deformation or damage to the electrode tab (27) and maintains the precision of the forming process.

[0118] A plurality of connecting parts (132) are each positioned toward the center point (C) of the pressing part (120) and can be connected to the pressing part (120). This connecting structure can strengthen the integrity through physical coupling between the pressing part (120) and the connecting part (132). This prevents minute positional misalignment or uneven bending that may occur during the forming process.

[0119] The foil tab forming device (100) according to the present embodiment may be designed to operate with the center point (C) of the pressurizing unit (120) and the winding axis of the electrode assembly (20) aligned. This alignment provides a basis for the pressurizing unit (120) to press the electrode tab (27) accurately and uniformly, and can maximize the precision of the foil tab forming process.

[0120]

[0121] Hereinafter, the process of bending the electrode tab (27) of the electrode assembly (20) using the foil tab forming device (100) according to the present embodiment will be described in detail, focusing on the process.

[0122] FIG. 8 is a drawing for explaining the appearance of the electrode assembly (20) of FIG. 3 being pressed against the pressing part (120) of the foil tab forming device (100) of FIG. 6, FIG. 9 is a cross-sectional view along the AA' cutting line of FIG. 8, FIG. 10 is a drawing for explaining the appearance of the electrode tab (27) of FIG. 4 being divided into multiple areas, and FIG. 11 is a drawing for explaining the appearance of the electrode tab of FIG. 5 being divided into multiple areas.

[0123] Referring to FIGS. 8 to 11, the foil tab forming device (100) according to the present embodiment can move toward the electrode assembly (20), or the electrode assembly (20) can move toward the foil tab forming device (100) so that the pressing part (120) and the electrode tab (27) can come into contact.

[0124] In the process where the electrode tab (27) is pressed by the pressurizing unit (120), the pressurizing unit (120) can provide the necessary pressure to maintain the arrangement of the electrode tab (27) uniformly and to stably bend the electrode tab (27) during the subsequent forming process.

[0125] The movement of the foil tab forming device (100) or the movement of the electrode assembly (20) can be performed by an automated system or manual control, thereby enabling the simultaneous achievement of precision and productivity in the manufacturing process.

[0126] The foil tab forming device (100) of the present embodiment may include an insertion part (150) designed to be inserted to a predetermined depth into the center hole (H1) of the electrode assembly (20).

[0127] The insertion part (150) can stably fix the electrode assembly (20) and support the pressing part (120) to precisely press the electrode tab (27).

[0128] Additionally, the insertion part (150) can prevent the electrode tab (27) from obstructing the center hole (H1) during the forming process. Through this, the welding rod can be smoothly inserted into the center hole (H1) during the subsequent welding process.

[0129] Specifically, the insertion part (150) can process or align the electrode tab (27) together with the pressurizing part (120) while inserted into the center hole (H1) of the electrode assembly (20). In this process, the insertion part (150) can prevent the electrode tab (27) from encroaching upon or obscuring the area of ​​the center hole (H1) during bending. For example, as described above, the electrode tabs (27) of the first electrode (21) and the second electrode (22), which are positioned at both ends of the winding axis direction of the electrode assembly (20) to which the foil tab forming device (100) of the present embodiment can be used, can be configured to be formed up to the core side. In addition, the height of each electrode tab (27) protruding in the winding axis direction from the core of the electrode assembly (20) to the outer circumference side can be configured to have the same shape.

[0130] As a result, the electrode tab (27) placed on the core side of the electrode assembly (20) to which the foil tab forming device (100) of the present embodiment can be used may encroach upon or obscure the area of ​​the center hole (H1) due to pressure during the forming process. At this time, the foil tab forming device (100) of the present embodiment can prevent the electrode tab (27) placed on the core side of the electrode assembly (20) from encroaching upon or obscuring the area of ​​the center hole (H1) in advance by inserting the insertion part (150) into the center hole (H1) of the electrode assembly (20) simultaneously with the pressure applied by the pressure part (120). Thus, the present invention ensures that the center hole (H1) maintains its function as a reform hole even after the forming process, which can improve the welding processability of the battery cell assembly process.

[0131] In this way, the insertion part (150) ensures accessibility to the center hole (H1) during the welding process, thereby preventing in advance the problem of the welding rod being obstructed due to the arrangement and position of the electrode tab (27). Through this, errors that may occur during the welding process can be reduced and the precision of the assembly process can be increased.

[0132] As an example, the insertion part (150) may be designed to be connected to the base part (110) and protrude from the base part (110) by a predetermined length (L5). Alternatively, as an example, the insertion part (150) may be designed to protrude further by a predetermined length (L6) than the length from the base part (110) to the pressing part (120) with respect to the winding axis direction.

[0133] As a result, the insertion part (150) can be first inserted into the center hole (H1) of the electrode assembly (20) to align the electrode assembly (20), and the pressing part (120) can press the electrode tab (27) at an appropriate position. This design can provide a stable foundation in which the insertion part (150) accurately fixes the electrode assembly (20) while the pressing part (120) can uniformly process the electrode tab (27).

[0134] The pressure member (120) may be configured to apply pressure to the electrode tab (27) in the direction of the winding axis while the insertion member (150) is inserted into the center hole (H1) of the electrode assembly (20). In this process, the pressure member (120) can adjust the arrangement and position of the electrode tab (27) and provide the necessary pressure so that the electrode tab (27) can be uniformly bent during the subsequent forming process. Additionally, by inserting the insertion member (150) into the center hole (H1), the electrode assembly (20) can be stably maintained without shaking or error in position during the pressure and forming processes.

[0135] The insertion part (150) can be adjusted to fit the size and depth of the center hole (H1) of the electrode assembly (20) and can be provided in a pin shape. Additionally, it can have a circular, polygonal, or specific cross-section as needed. This allows for flexible application to various electrode assembly (20) structures and sizes.

[0136] The pressurizing part (120) can be designed to have a length (L8) longer than the length (L7) of the electrode assembly (20) in the radial direction. This allows the pressurizing part (120) to stably pressurize the entire area of ​​the electrode assembly (20), particularly up to the electrode tab (27) located at the edge.

[0137] The electrode tab (27) located at the edge of the electrode assembly (20) may be difficult to support and pressurize compared to the inner area due to the arrangement characteristics, and if the pressure is not uniform, there is a possibility of defects occurring during the forming and subsequent welding processes. By having a longer length (L8) that exceeds the length (L7) of the electrode assembly (20), the electrode tab (27) located at the edge of the electrode assembly (20) can also be designed to receive uniform pressure.

[0138] As such, the foil tab forming device (100) according to the present embodiment may be designed to maintain the arrangement of electrode tabs (27) in a stable and uniform manner overall by having a pressurizing part (120) and an insertion part (150). For example, the electrode tabs (27) can be divided into four sections at 90-degree intervals by utilizing the pressurizing part (120) and the forming jig (131). If necessary, the number and angle of the sections can be adjusted to suit the size of the electrode tabs (27) or battery design requirements. As an example, subdivided sections such as six or eight sections are also possible, which can provide design flexibility to flexibly respond to various battery cell shapes and sizes.

[0139] As illustrated in FIG. 10, in an embodiment in which the foil tab forming device (100) of the present embodiment can be used, the electrode assembly (20) can be aligned and formed such that the electrode tab (27) placed on the core side of the electrode assembly (20) by the action of the insertion part (150) does not encroach upon or obstruct the area of ​​the center hole (H1). This design ensures proper placement of the electrode tab (27) while maintaining the structural function of the center hole (H1), thereby increasing work efficiency in subsequent processes.

[0140] Meanwhile, the electrode assembly (20) according to another embodiment illustrated in FIG. 11 may be configured such that the electrode tab (27) on the core side is omitted or the width in the winding axis direction is relatively small. In this case, even without using the insertion part (150), the electrode tab (27) can be formed without encroaching upon or obscuring the area of ​​the center hole (H1) of the electrode assembly (20). However, even in this case, the foil tab forming device (100) of the present embodiment can further improve the alignment quality of the electrode tab (27) and minimize functional interference with the center hole (H1) by inserting the insertion part (150) into the center hole (H1) of the electrode assembly (20) so that at least a part of the electrode tab (27) does not extend into the area of ​​the center hole (H1). This design can maintain the structural function of the center hole (H1) in the battery cell assembly process and ensure consistency in the assembly process through the alignment and placement of the electrode tab (27).

[0141] Thus, the foil tab forming device (100) according to the present embodiment can contribute to improving the quality of the battery cell assembly process and maximizing the efficiency of subsequent forming and welding processes.

[0142]

[0143] FIG. 12 is a drawing for explaining the appearance of the electrode assembly (20) of FIG. 3 being pressed by the forming part (130) of the foil tab forming device (100) of FIG. 6, FIG. 13 is a drawing for explaining the appearance of the electrode tab (27) of FIG. 4 being bent radially inward, and FIG. 14 is a drawing for explaining the appearance of the electrode tab of FIG. 5 being bent radially inward.

[0144] Referring to FIGS. 12 and 14, a plurality of forming sections (130) can be designed to bend the electrode tab (27) radially inward with respect to the outer surface of the electrode assembly (20) while the electrode tab (27) is pressed in the direction of the winding axis by the pressing section (120). As a result, the arrangement and bending of the electrode tab (27) can be performed accurately and uniformly, and the quality and precision of the battery cell assembly process can be improved.

[0145] The forming section (130) can be configured to operate when the insertion section (150) is inserted into the center hole (H1) of the electrode assembly (20). In this state, the pressurizing section (120) and the forming section (130) may have a structure that surrounds the electrode tab (27) in each of the partitioned multiple areas. This design allows each electrode tab (27) to be pressurized and bent within an independent area, thereby preventing interference between the electrode tabs (27) and enhancing the stability of the forming process.

[0146] For example, when the insertion part (150) is inserted into the center hole (H1), the alignment of the electrode assembly (20) is maintained, and a basis is provided for the pressing part (120) and the forming part (130) to operate uniformly with respect to the electrode tab (27). That is, the configuration surrounding the electrode tab (27) within the partitioned area allows the electrode tab (27) to maintain a stable position between the pressing part (120) and the forming part (130), and prevents slip or deformation from occurring during the bending process.

[0147] In addition, this configuration maintains the arrangement and bending angle of the electrode tabs (27) uniformly, thereby minimizing errors that may occur during subsequent welding processes and ensuring the electrical performance and assembly quality of the battery.

[0148] In conclusion, the foil tab forming device (100) according to the present embodiment can be designed so that each partitioned electrode tab (27) is formed to have a constant bending direction radially inward with respect to the center hole (H1) within the partitioned area. Through this, a structure can be formed in which the electrode tabs (27) are uniformly arranged radially inward overall.

[0149] For example, when the electrode tab (27) of the electrode assembly (20) is divided into four regions, each region can be defined as P1, P2, P3, and P4. In this case, the electrode tab (27) within each region has the same bending direction, and all electrode tabs within regions P1, P2, P3, and P4 can be designed to face inward in the radial direction relative to the center hole (H1). This arrangement allows the electrode tab (27) in each region to maintain an aligned state within the region, thereby enabling uniform and precise forming overall.

[0150] This arrangement method ensures that the forming thickness of the electrode tabs (27) is formed uniformly throughout, and prevents interference between the electrode tabs (27), thereby improving the assembly quality of the electrode assembly (20). In addition, the stability of the electrode tab (27) arrangement can be maintained even after the forming process, thereby maximizing precision and work efficiency in the subsequent welding process.

[0151]

[0152] FIG. 15 is a flowchart of a foil tab forming method according to one embodiment of the present invention, and FIG. 16 is a flowchart of a foil tab forming method according to another embodiment of the present invention.

[0153] Referring to FIGS. 15 and 16, the foil tab forming method according to the present embodiment may include the process of forming an electrode assembly (20) using the foil tab forming device (100) described above.

[0154] First, a step of preparing an electrode assembly (20) is performed. In this step, the electrode assembly (20) is prepared by winding it with a center hole (H1) formed therein, and can then be appropriately positioned to perform alignment and forming processes with a foil tab forming device (100).

[0155] Next, a process of aligning the center hole (H1) of the electrode assembly (20) and the center point (C) of the pressurizing part (120) of the foil tab forming device (100) may be performed. This alignment step can contribute to ensuring precision so that the arrangement and bending direction of the electrode tab (27) can be maintained uniformly during the forming process.

[0156] Once alignment is complete, the electrode tab (27) can be pressed along the winding axis direction using the pressurizing unit (120). During this process, the electrode tab (27) can be divided into a plurality of independent regions. This step is a preparatory step for performing a subsequent banding process, allowing the electrode tab (27) to be uniformly arranged within the divided regions.

[0157] Here, the process may additionally include inserting an insertion part (150) designed to be inserted to a certain depth into the center hole (H1) of the electrode assembly (20), and simultaneously applying pressure to the electrode tab (27) using a pressure part (120). The insertion part (150) can perform the function of aligning the position of the electrode assembly (20) and stably fixing it by being inserted into the center hole (H1). In addition, the insertion part (150) is inserted into the center hole (H1) of the electrode assembly (20) so that the electrode tab (27) does not cover the reform hole during a subsequent welding process, thereby ensuring the efficiency and reliability of the welding process.

[0158] Finally, the forming part (130) provided in each partitioned area can be moved toward the center point (C) of the pressing part (120) to bend the electrode tab (27) radially inward. In this process, each forming part (130) precisely bends the electrode tab (27) within the partitioned area and can maintain a consistent alignment of the electrode tab (27) arrangement overall. Through this, the forming thickness of the electrode assembly (20) is formed uniformly, and the stability of the electrode tab (27) arrangement can be guaranteed.

[0159] Thus, the present invention can contribute to simultaneously improving quality and productivity throughout the battery cell manufacturing process.

[0160]

[0161] As described above, although the present invention has been explained by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

[0162] [Explanation of Symbol] 20: Electrode Assembly

[0163] 21: First electrode

[0164] 22: Second electrode

[0165] 23: Metal foil

[0166] 24: Maintenance Department

[0167] 25: Active material layer

[0168] 26: Mujibu

[0169] 27: Electrode tab

[0170] 28: Separator

[0171] 100: Foil tab forming device

[0172] 110: Base section

[0173] 120: Pressurizing part

[0174] 130: Forming Department

[0175] 131: Forming Jig

[0176] 132: Connection

[0177] 150: Insert

[0178] H1: Center hole

[0179] C: Center point

Claims

A foil tab forming device for forming an electrode tab exposed at one end of an electrode assembly wound around a winding axis by laminating a first electrode, a separator, and a second electrode, A base portion having a flat surface; A pressure member protruding in the direction of the winding axis from the flat surface of the base portion and configured to divide the electrode tab into a plurality of regions; and A foil tab forming device characterized by including a plurality of forming parts provided in a plurality corresponding to the plurality of partitioned areas, each configured to bend an electrode tab radially inward around a winding axis within each of the partitioned areas. In Article 1, The above-mentioned pressurizing unit is, A foil tab forming device characterized by having a radial structure based on the center point of the above-mentioned pressurizing part. In Article 1, The above-mentioned pressurizing unit is, A foil tab forming device characterized by having a length longer than the length of the electrode tab with respect to the winding axis direction. In Article 1, The above plurality of forming parts are, respectively, A foil tab forming device comprising a forming jig, wherein the forming jig is configured to move toward the center point of the pressurizing part. In Paragraph 4, The above plurality of forming parts are, respectively, It includes a connecting part provided on the flat surface of the base part, and The above forming jig is, A foil tab forming device characterized by being coupled to the above-mentioned connecting part and configured to move along the longitudinal direction of the above-mentioned connecting part. In Article 5, The above forming jig is, A foil tab forming device characterized by having a length longer than the length of the electrode tab with respect to the winding axis direction. In Article 5, The above-mentioned pressurizing unit is, A foil tab forming device characterized by being disposed between adjacent connecting parts. In Article 5, A plurality of the above-mentioned connecting parts are, A foil tab forming device characterized by having a symmetrical structure based on the center point of the above-mentioned pressure part. In Article 5, A plurality of the above-mentioned connecting parts, each, A foil tab forming device characterized by being spaced apart from the center point of the above-mentioned pressure member at a predetermined distance. In any one of paragraphs 1 through 9, The above foil tab forming device is, A foil tab forming device characterized by including an insertion part configured to be inserted to a predetermined depth into the center hole of the electrode assembly. In Article 10, The above insert is, A foil tab forming device characterized by being protruding further from the base portion than the pressurizing portion with respect to the winding axis direction. In Article 1, The above-mentioned pressurizing unit is, A foil tab forming device characterized by having a length longer than the length of the electrode assembly based on the radial direction. In Article 10, The above-mentioned pressurizing unit is, A foil tab forming device characterized by the above-mentioned insertion part being inserted into the center hole of the electrode assembly and configured to press the electrode tab in the direction of the winding axis. In Article 13, The above plurality of forming parts are, respectively, A foil tab forming device characterized by being configured to bend the electrode tab radially inward from the outer surface of the electrode assembly while the electrode tab is pressed in the winding axis direction by the above-mentioned pressurizing part. In Article 14, The above-mentioned pressurizing part and the above-mentioned forming part are, A foil tab forming device characterized by being configured such that when the above-mentioned insertion part is inserted into the above-mentioned central hole, it surrounds the electrode tab in each of the above-mentioned partitioned multiple regions. A foil tab forming method for forming an electrode tab exposed at one end of an electrode assembly wound around a winding axis by laminating a first electrode, a separator, and a second electrode, wherein A first step of preparing the above electrode assembly; A second step of aligning the center hole of the electrode assembly and the center of the pressure part in a line; A third step of applying pressure to the electrode tab along the winding axis direction with the above-mentioned pressure member to divide the electrode tab into a plurality of regions; and A foil tab forming method characterized by including a fourth step of moving each forming part provided in each of the partitioned areas toward the center of the pressurizing part to bend the electrode tab radially inward. In Article 16, The above third step is, A foil tab forming method characterized by inserting an insertion part configured to be inserted to a certain depth into the center hole of the electrode assembly, and simultaneously pressing the electrode tab by the pressing part.

Images