Method for monitoring bending position of electrode tab and electrode assembly winding device using same

Abstract

Provided is a method for monitoring the bending position of a pre-bent electrode tab in real time prior to a winding process of an electrode assembly. The monitoring target is the position where the electrode tab has been bent. The method comprises the steps of: acquiring an image by means of a camera positioned such that the photographing direction thereof is substantially perpendicular to a plane including an electrode, the image being acquired by detecting reflected light from a bent non-coated portion that has been irradiated in a direction substantially parallel to the photographing direction; and measuring, from the image acquired by the image acquisition device, a distance from a cutting groove, which constitutes an inner end of a cut portion in the width direction, to the bending line.

Description

Method for monitoring the bending position of an electrode tab and an electrode assembly winding device using the method

[0001] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2024-0084453, dated June 27, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a method for monitoring the bending position of an electrode tab, and more particularly, to a method for monitoring the bending position of a pre-bent electrode tab in real time prior to a process of winding an electrode assembly, and to an electrode assembly winding device that can correct the bending process of an electrode tab in real time by applying the method.

[0003] With the proliferation of electric vehicles, the capacity of cylindrical battery cells, manufactured using cylindrical battery cans as housings, is increasing. Battery cells installed in vehicles are desirable for their high energy density to conserve space and for their light weight to enhance driving efficiency. Therefore, designs are underway to not only manufacture larger cylindrical battery cells but also maximize energy density by filling the internal space of the cells with electrode assemblies.

[0004] As part of this design, the electrode tabs are formed by allowing the uncoated portion of the first electrode and the uncoated portion of the second electrode to protrude from the axial first and second ends of the jelly-roll-shaped electrode assembly, respectively, and bending the uncoated portions in the radial direction.

[0005] However, since the non-conductive portion is a current collector portion in the form of a thin metal foil, the electrode tabs can become unintentionally deformed during the process of processing the non-conductive portion to form the electrode tabs. Such deformation of the electrode tabs can cause product defects and deterioration of product performance.

[0006] The present invention has been devised to solve the above-described problem, and aims to provide a method capable of monitoring whether the non-conductive portion of an electrode assembly is bent at a designed position.

[0007] The purpose of the present invention is to provide a method capable of monitoring the bending position of the above-mentioned non-conductive portion in real time during an electrode assembly manufacturing process, and an electrode assembly winding device using the method.

[0008] The purpose of the present invention is to provide a monitoring method capable of correcting the bending position of the electrode tab in real time so that the bending position of the non-conductive portion does not deviate from the designed position, and an electrode assembly winding device using the method.

[0009] The technical objectives of the present invention are not limited to the aforementioned purposes. Other unmentioned objectives and advantages of the present invention can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0010] In order to solve the above-described problem, the present invention can be applied to an electrode assembly winding device that assembles a jelly-roll-shaped electrode assembly by winding a first electrode and a second electrode with a separator interposed therebetween.

[0011] The above electrode may be in the form of a current collector in which an active material is applied to the surface of the current collector in the form of a metal foil. The electrode may include a holding portion in which the active material is applied to the surface of the current collector, and a non-conductive portion in which the active material is not applied to the surface of the current collector.

[0012] The above electrode can be extended in the longitudinal direction with a predetermined width.

[0013] The above-mentioned non-conductive portion may be placed at the first end in the width direction of the electrode.

[0014] The above-mentioned non-conductive portion may have a plurality of cut portions extending from the outer end in the width direction to the inner end in the width direction and spaced apart from each other along the length direction of the electrode. The non-conductive portion between two adjacent cut portions in the length direction may form an electrode tab. That is, the plurality of cut portions may define a plurality of electrode tabs arranged along the length direction.

[0015] The above electrode tab is positioned at a predetermined distance from the cut groove in the width direction as defined by the widthwise inner end of the cut portion, and can be bent in a bending direction that intersects both the width direction and the length direction of the electrode based on a bending line parallel to the length direction of the electrode.

[0016] Such bending may be a preliminary bending performed before winding of the electrode.

[0017] In this way, the electrode tabs are pre-bent, the first electrode and the second electrode, and the separator interposed between them are wound to assemble a jelly-roll-shaped electrode assembly, and then the pre-bent electrode tabs can be finally bent.

[0018] The above electrode assembly winding device includes a forming unit that pre-bends the electrode tab based on the bending line.

[0019] The above forming unit may be provided with a first roller and a second roller that contact both sides of the electrode and cause the electrode to travel in the longitudinal direction.

[0020] A pressure roller section for pressing the electrode tab in the bending direction may be provided at the axial first end of the first roller.

[0021] A support roller section that limits the bending angle of the electrode tab that is pre-bent by the pressure roller section may be provided at the axial second end of the second roller.

[0022] The electrode tab of the above electrode can be pre-bent while passing through the forming unit.

[0023] The above electrode assembly winding device includes a distance measuring unit that measures the distance from the cut groove to the bending line of the pre-bent electrode tab in the width direction of the electrode.

[0024] The above electrode assembly winding device includes a winding unit that winds the electrode with the electrode tab bent to form an electrode assembly.

[0025] The above distance measuring unit can be placed between the forming unit and the winding unit.

[0026] The above electrode assembly winding device may include a control unit that monitors whether the distance measured by the distance measuring unit deviates from a predetermined standard.

[0027] The above distance measuring unit may be equipped with an image acquisition device that acquires an image including a portion of the non-woven fabric bent by the forming unit.

[0028] The image acquisition device may include a camera that photographs the folded ungual area and a light that illuminates the folded ungual area.

[0029] The above lighting may be coaxial lighting that irradiates light to the non-photographic portion bent in a direction substantially parallel to the shooting direction.

[0030] The shooting direction of the above camera may be substantially perpendicular to the plane including the electrode. The camera may be spaced apart from the upper surface of the folded non-conductive portion.

[0031] The above coaxial lighting may include a mirror portion arranged on the shooting direction line of the camera. The mirror portion may be arranged between the surface of the folded non-fold portion and the camera, at a position spaced upward from the surface of the non-fold portion.

[0032] The above coaxial lighting may include a light emitting unit that emits light to the mirror unit in a direction intersecting the shooting direction. The light emitting unit may be positioned laterally apart from the shooting direction line.

[0033] The camera may receive reflected light substantially parallel to the shooting direction from among the light reflected from the non-photographic area by the coaxial lighting. The camera may detect the incident light and acquire the image.

[0034] Among the light irradiated to the above-mentioned uneven portion, light irradiated to the non-folded surface of the uneven portion may be reflected and incident on the camera. Among the light irradiated to the above-mentioned uneven portion, light irradiated to the folded surface of the uneven portion may be reflected in a direction different from the shooting direction and may not be incident on the camera.

[0035] The above reflected light can pass through the mirror section and enter the camera.

[0036] The distance measuring unit may include a distance calculating device that calculates the distance from the incision bone portion to the bending line from an image acquired by the image acquiring device.

[0037] The above distance calculation device can recognize the position of the cut groove and the position of the bending line from the difference in contrast ratio distinguished by the incident light in the image acquired by the camera, and calculate the distance between the recognized position of the cut groove and the position of the bending line.

[0038] The above control unit can obtain an average value of a plurality of predetermined distances and determine whether the average value deviates from the above standard.

[0039] The above control unit can adjust the widthwise position of the forming unit to compensate for the average value being determined to be outside the above standard.

[0040] The present invention provides a method for monitoring the bending position of the electrode tab.

[0041] The method includes a step of acquiring an image by detecting reflected light reflected from the folded portion of the non-woven fabric in a direction substantially parallel to the shooting direction, with the camera positioned so that the shooting direction is substantially perpendicular to the plane including the electrode.

[0042] The method includes a step of measuring a distance from the incision bone to the bend line from an image acquired by the image acquisition device.

[0043] In the image acquisition step, light is irradiated to the mirror portion placed on the shooting direction line of the camera in a direction intersecting the shooting direction, and the irradiated light reflected from the mirror portion can be projected onto the non-photographic portion in parallel with the shooting direction.

[0044] In the image acquisition step, among the lights projected and reflected on the non-focus area, the reflected light that is reflected substantially parallel to the shooting direction can pass through the mirror section and be incident on the camera.

[0045] The above measurement step may include a procedure for recognizing the position of the incision groove and the position of the bending line from the difference in contrast ratio distinguished by light reflected from the surface of the non-woven material and incident on the camera in the image acquired by the camera, and calculating the distance between the recognized position of the incision groove and the position of the bending line.

[0046] The above method may further include a step of calculating an average value of a plurality of predetermined distances produced, determining whether the average value deviates from the above standard, and adjusting the widthwise position of a forming unit that performs bending processing to correct the average value if it is determined that the average value deviates from the above standard.

[0047] According to the method for monitoring the bending position of an electrode tab according to the present invention, it is possible to monitor in real time whether the electrode tab has been pre-bent at a designed position before assembling an electrode assembly, and based on this, it is possible to correct in real time so that the bending position of the electrode tab does not deviate from the designed position.

[0048] The electrode assembly winding device according to the present invention can monitor the bending position of the electrode tab in real time and correct the bending position in real time. Accordingly, defects occurring during the electrode assembly assembly process can be reduced.

[0049] In addition to the effects described above, specific effects of the present invention are described below while explaining specific details for carrying out the invention.

[0050] Figure 1 is an exploded perspective view of the electrodes and separators that make up the electrode assembly.

[0051] Fig. 2 is a perspective view schematically illustrating a process of transferring an electrode to the forming unit of Fig. 1 and pre-bending an electrode tab.

[0052] Figure 3 is a perspective view schematically showing a process of stacking a first electrode and a second electrode with pre-bent electrode tabs and a separator interposed therebetween and winding them with a winding unit.

[0053] Fig. 4 is a perspective view showing the final bent state of the electrode tab of the electrode assembly wound by the winding process of Fig. 3.

[0054] Figure 5 is a side view of a forming unit that transports an electrode and pre-bends an electrode tab, and a control unit connected thereto.

[0055] FIG. 6 is a perspective view showing an image acquisition device that is arranged between the forming unit of FIG. 2 and the winding unit of FIG. 3 and photographs a pre-bent bending tab.

[0056] Fig. 7 is a perspective view showing an image acquisition device including the image acquisition device and distance calculation device of Fig. 6, and a control unit connected thereto.

[0057] Figure 8 is an enlarged view showing light irradiated onto a non-conductive area including a pre-folded electrode tab and light reflected from the irradiated light.

[0058] Figure 9 is a drawing showing an image acquired by the image acquisition device of Figure 6.

[0059] Figure 10 is a drawing showing a state in which the incision bone portion and the bend line are recognized in the image of Figure 9 and the distance between them is calculated.

[0060] [Explanation of symbols]

[0061] 10: Electrode assembly winding device 20: Electrode assembly 21: First electrode 22: Second electrode 23: Current collector 24: Active material 25: Supporting portion 26: Non-coated portion 27: Electrode tab 28: Separator 29: Core hollow portion 30: Cut portion 32: Cut groove portion 34: Bending line 35: Bending area 36: Unbending area 40: Forming unit 41: First roller 411: Pressing roller portion 42: Second roller 422: Support roller portion 50: Distance measuring unit 51: Image acquisition device 52: Camera 53: Coaxial lighting 531: Light emitting portion 532: Mirror portion 55: Distance calculation device 60: Control portion 70: Winding unit

[0062] The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily practice the technical idea of ​​the present invention. In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0063] Although terms like "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0064] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0065] Hereinafter, the phrase "any configuration is placed on (or below)" a component or "on (or below)" a component may mean that any configuration is placed in contact with the upper surface (or lower surface) of said component, and that other configurations may be interposed between said component and any configuration placed on (or below) said component.

[0066] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0067] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0068] Throughout the specification, when we refer to "A and / or B", this means A, B, or A and B, unless otherwise stated, and when we refer to "C through D", this means C or more and D or less, unless otherwise stated.

[0069] In describing the embodiments, the axial direction refers to the direction in which the axis forming the winding center of the jelly-roll type electrode assembly extends, the radial direction (radial direction) refers to the direction approaching or away from the axis, and the circumferential direction (circumferential direction) refers to the direction surrounding the axis. The axial direction corresponds to the width direction of the electrode, and the circumferential direction corresponds to the length direction of the electrode.

[0070] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0071] Referring to FIGS. 2, 3, and 5 to 7, the electrode assembly winding device () of the embodiment includes a forming unit (40) that transports electrodes (21, 22) and pre-bends electrode tabs (27), a winding unit (70) that winds the first electrode (21) and the second electrode (22) whose electrode tabs (27) are pre-bent and a separator (28) interposed therebetween, a distance measuring unit (50) that is disposed between the forming unit (40) and the winding unit (70) and measures a bending position of a portion of the bent electrode tab (27), and a control unit (60) that controls the forming unit (40) based on the bending position of the electrode tab (27) measured by the distance measuring unit (50) to correct the bending position.

[0072] Referring to Fig. 1, the electrodes (21, 22) have a form in which an active material (24) is applied to the surface of a current collector (23) in the form of a metal foil. The electrodes (21, 22) include a holding portion (25) in which the active material (24) is applied to the surface of the current collector (23), and a non-conductive portion (26) in which the active material (24) is not applied to the surface of the current collector (23). The electrodes (21, 22) have a predetermined width and extend in the longitudinal direction. The non-conductive portion (26) of the first electrode (21) is arranged at a first end in the width direction of the first electrode (21), and the non-conductive portion (26) of the second electrode (22) is arranged at a second end in the width direction of the second electrode (22).

[0073] Referring to FIGS. 1 and 2, a plurality of cut portions (30) extending from the outer end in the width direction to the inner end in the width direction are spaced apart from each other along the length direction of the electrodes (21, 22) in the non-coated portion (26) by laser notching. The portion of the non-coated portion (26) between two adjacent cut portions (30) in the length direction constitutes an electrode tab (27). That is, the plurality of cut portions (30) define a plurality of electrode tabs (27) arranged along the length direction. In this way, notches can be formed at predetermined intervals in the non-coated portion (26) to form electrode tabs (27) in the shape of flags.

[0074] In the embodiment, the electrode tabs (27) are exemplified as having an equilateral trapezoidal shape. However, their shapes may be various, such as a semicircle, a semi-ellipse, a triangle, a rectangle, or a parallelogram.

[0075] In addition, in the embodiment, a form in which the electrode tabs (27) arranged along the longitudinal direction have the same width is exemplified. However, the width of the electrode tabs may be gradually or stepwise widened from the core side to the outer periphery side.

[0076] In addition, in the embodiment, a form in which the height of the electrode tabs (27) gradually increases from the core side to the outer circumference side is exemplified. However, the height of these electrode tabs may be implemented in a form in which they are constant or gradually decrease.

[0077] In addition, in the embodiment, a structure is exemplified in which the electrode tab (27) is deleted in a predetermined section of the centripetal end of the non-conductive portion (26) and a predetermined section of the centrifugal end. However, it is of course possible that the electrode tab may not be deleted in the centripetal end of the non-conductive portion, or that the electrode tab may not be deleted in the centrifugal end of the non-conductive portion, or that neither may be deleted.

[0078] Referring to FIGS. 2 and 8, before winding the electrodes (21, 22), the electrode tabs (27) are arranged at a position spaced a first distance outward in the width direction from the cut grooves (32) defined by the width direction inner ends of the cut portions (30) and are pre-bent in a bending direction that intersects both the width direction and the length direction of the electrodes (21, 22) based on a bending line (34) parallel to the length direction of the electrodes (21, 22). The position of the cut grooves (32) is arranged at a position spaced a second distance outward in the width direction from the boundary between the non-coated portion (26) and the holding portion (25) regardless of the height of the electrode tabs, and the position of the pre-bending can be arranged at a position spaced a first distance outward from the cut grooves (32) regardless of the height of the electrode tabs.

[0079] Referring to FIGS. 2 and 5, the forming unit (40) pre-bends the electrode tab (27) based on the bending line (34). The forming unit (40) includes a first roller (41) and a second roller (42) which contact both sides of the electrodes (21, 22) and cause the electrodes (21, 22) to travel in the longitudinal direction. At the axial ends of the first roller (41) and the second roller (42) corresponding to the direction in which the uncoated portion (26) of the electrodes (21, 22) is provided, a pressure roller part (411) which presses the electrode tab (27) in the bending direction and a support roller part (422) which limits the bending angle of the electrode tab (27) pre-bent by the pressure roller part (411) are respectively provided. The electrode tab (27) of the above electrode (21, 22) passes through the forming unit and is pre-bent by the pressure roller unit (411) and the support roller unit (422).

[0080] As shown in Fig. 5, in order to control the position of the bending line (34), the control unit (60) can adjust the widthwise positions of the first roller (41) and the second roller (42).

[0081] In this way, the first electrode (21) and the second electrode (22) with the electrode tab (27) preliminarily bent are wound in the longitudinal direction with a separator (28) interposed between them by a winding unit (70), as shown in Fig. 3. Accordingly, a jelly-roll-shaped electrode assembly (20) is manufactured.

[0082] As shown in Fig. 4, the coiled electrode assembly (20) is formed by finally bending the pre-bent electrode tabs (27) to form surfaces of flat electrode tabs (27) that are substantially perpendicular to the axial direction of the electrode assembly.

[0083] Referring to FIGS. 6 and 7, the distance measuring unit (50) is disposed between the forming unit (40) and the winding unit (70), and measures the distance from the cut groove (32) to the bending line (34) of the pre-bent electrode tab (27) in the width direction of the electrode (21, 22).

[0084] The above distance measuring unit (50) includes an image acquisition device (51) that acquires an image including a portion of the non-woven part (26) bent by the forming unit, and a distance calculation device (55) that calculates the distance from the cut bone part (32) to the bending line (34) from the image acquired by the image acquisition device (51).

[0085] The above image acquisition device (51) is equipped with a camera (52) that photographs the folded plain portion (26) area, and a coaxial light (53) that irradiates light to the folded plain portion (26) area in a direction substantially parallel to the photographing direction.

[0086] The shooting direction of the above camera (52) is substantially perpendicular to the plane including the electrodes (21, 22). For this purpose, the camera (52) is spaced apart from the upper surface of the folded non-conductive portion (26).

[0087] The above coaxial lighting (53) comprises a mirror portion (532) arranged on the photographing direction line of the camera (52), and a light emitting portion (531) that emits light to the mirror portion (532). The mirror portion (532) is arranged between the surface of the folded non-coated portion (26) and the camera (52) at a position spaced upward from the surface of the non-coated portion (26). The light emitting portion (531) is arranged spaced laterally from the photographing direction line, and emits light to the mirror portion (532) in a direction intersecting the photographing direction, more specifically, substantially perpendicularly.

[0088] As shown in FIGS. 7 and 8, among the light irradiated to the non-folded area (35) of the light irradiated to the non-folded area (26), the light irradiated is vertically reflected back and incident on the camera (52). On the other hand, among the light irradiated to the non-folded area (26), the light irradiated to the folded area (35) is reflected in a different direction intersecting with the photographing direction and is not incident on the camera (52).

[0089] The camera (52) receives reflected light that is substantially parallel to the shooting direction among the light reflected by the coaxial light (53) on the non-photographic part (26). The reflected light passes through the mirror part (532) and enters the camera (52). In this way, the camera (52) detects the incident light and acquires the image.

[0090] In the image acquired in this way, as shown in Fig. 9, the area corresponding to the unbent area (35) of the plain part (26) becomes bright, and the area corresponding to the bent area (35) of the plain part (26) becomes dark. Of course, the maintenance area (25) and the background (B) portion also become dark enough to be distinguishable from the area corresponding to the bent area (35) of the plain part (26).

[0091] The above distance calculation device (55) recognizes the position of the cut groove (32) and the position of the bending line (34) from the difference in contrast ratio distinguished by the incident light in the image acquired by the camera (52), as shown in FIG. 10, and calculates the distance between the recognized position of the cut groove (32) and the position of the bending line (34).

[0092] The control unit (60) monitors whether the distance measured by the distance measuring unit (50) deviates from a predetermined standard. The control unit (60) calculates an average value of a plurality of predetermined distances and determines whether the average value deviates from the standard. Although the distance values ​​may differ individually, if the average value remains constant, there is no need to control the widthwise position of the forming unit (40). However, if the average value gradually moves away from the standard value, it is necessary to adjust the position of the forming unit (40). If the control unit (60) determines that the average value deviates from the standard, it adjusts the widthwise position of the forming unit as illustrated in FIG. 5 to compensate for this. This monitoring and position correction of the bending position can be performed in real time on the production line.

[0093] Below, a method for monitoring the bending position of the electrode tab (27) is described.

[0094] First, the camera (52) is positioned so that the shooting direction is substantially perpendicular to the plane including the electrodes (21, 22), and an image is acquired by detecting the reflected light reflected from the folded portion of the non-woven part (26) in a direction substantially parallel to the shooting direction.

[0095] At this time, light is irradiated to the mirror part (532) placed on the shooting direction line of the camera (52) in a direction intersecting the shooting direction, and the irradiated light reflected from the mirror part (532) is projected onto the uncoated part (26) portion parallel to the shooting direction. Then, among the lights projected and reflected onto the uncoated part (26), the reflected light reflected substantially parallel to the shooting direction in the unbent area (35) of the uncoated part (26) passes through the mirror part (532) and is incident on the camera (52).

[0096] Next, the distance from the incision groove (32) to the bending line (34) is measured from the image acquired by the image acquisition device (51). Specifically, in the image, the position of the incision groove (32) and the position of the bending line (34) are recognized and displayed from the difference in contrast ratio distinguished by light reflected from the surface of the non-woven part (26) and incident on the camera (52), and the distance between the position of the incision groove (32) and the position of the bending line (34) thus displayed is calculated.

[0097] Next, the average value of the multiple predetermined distances calculated as above is obtained and it is determined whether the average value falls outside the allowable standard range. If the average value is determined to be outside the standard, the widthwise position of the forming unit performing the bending process is adjusted to correct the bending position.

[0098] According to the embodiment, the preliminary bending of the electrode tab (27) can be inspected inline to enable overall quality control of the electrode assembly, and the possibility of the electrode tab (27) being deformed in an unintended direction, resulting in an internal short circuit, can be significantly reduced. The image acquisition is performed by photographing the preliminary bending position while the electrode (21, 22) is moving and passing the forming unit (40), thereby preventing delays in production time.

[0099] Additionally, in-line full inspection is possible and automatic equipment calibration is possible, so there is no need to stop equipment operation for equipment calibration.

[0100] It should be understood that the above-described embodiments are illustrative in all respects and not restrictive, and the scope of the present invention will be determined by the claims that follow, rather than by the detailed description set forth above. Furthermore, the meaning and scope of the claims that follow, as well as all possible modifications and variations derived from their equivalent concepts, should be construed as encompassing the scope of the present invention.

[0101] Although the present invention has been described with reference to the drawings exemplified above, it is to be understood that the present invention is not limited to the embodiments and drawings disclosed herein, and that various modifications may be made by those skilled in the art within the scope of the technical idea of ​​the present invention. Furthermore, even if the operational effects according to the configuration of the present invention have not been explicitly described while describing the embodiments of the present invention, it is natural that the effects predictable by the corresponding configuration should also be acknowledged.

Claims

1. A forming unit that bends a plurality of electrode tabs defined by a plurality of cut portions spaced apart from the outer end of the widthwise portion provided at the first end of the widthwise portion of the electrode extending in the lengthwise direction with a predetermined width and arranged in the widthwise direction along the lengthwise direction of the electrode, in a direction intersecting both the widthwise direction and the lengthwise direction with respect to a predetermined bending line arranged on the electrode tabs. A winding unit for winding the electrode with the electrode tab bent to form an electrode assembly; A distance measuring unit arranged between the forming unit and the winding unit, which measures the distance from the cutting groove, which is the inner end of the cutting portion in the width direction, to the bending line, and An electrode assembly winding device comprising a control unit that monitors whether the distance measured by the distance measuring unit deviates from a predetermined standard.

2. In claim 1, the distance measuring unit: An image acquisition device for acquiring an image including a portion of the non-woven fabric folded by the above-mentioned forming unit; An electrode assembly winding device, comprising a distance calculation device that calculates the distance from the incision bone portion to the bending line from an image acquired by the image acquisition device.

3. In claim 2, the image acquisition device, A camera that photographs the folded, non-flexible portion of the body so that the photographing direction is substantially perpendicular to the plane containing the electrode; and An electrode assembly winding device, comprising a coaxial light that irradiates light to the non-conductive portion in a direction substantially parallel to the photographing direction.

4. In claim 3, the coaxial lighting: A light emitting unit that irradiates light along the shooting direction line of the camera in a direction intersecting with the shooting direction; and An electrode assembly winding device further comprising a mirror portion arranged on the shooting direction line of the camera and reflecting light irradiated from the coaxial light onto a non-illuminated portion for image acquisition.

5. In claim 4, the camera detects the reflected light reflected from the non-visible portion by the coaxial illumination light to acquire an image, An electrode assembly winding device in which the above reflected light passes through the above mirror section.

6. In claim 3, the distance calculation device, An electrode assembly winding device that recognizes the position of the cut groove and the position of the bending line from the difference in contrast ratio distinguished by light reflected from the surface of the non-conductive part and incident on the camera in the image acquired by the camera, and calculates the distance between the recognized position of the cut groove and the position of the bending line.

7. In claim 6, the control unit calculates an average value of a plurality of predetermined distances, determines whether the average value deviates from the standard, and adjusts the widthwise position of the forming unit to compensate for the average value if it is determined that the average value deviates from the standard.

8. A method for monitoring a position where a plurality of electrode tabs, which are defined by a plurality of cut portions spaced apart from the outer end of the widthwise portion provided at the first end of the widthwise portion of an electrode extending in the lengthwise direction with a predetermined width and are bent in a direction intersecting both the widthwise direction and the lengthwise direction with respect to a predetermined bending line arranged on the electrode tabs, are bent. A step of acquiring an image by detecting reflected light reflected from the non-woven portion that has been irradiated and folded in a direction substantially parallel to the shooting direction, using a camera positioned so that the shooting direction is substantially perpendicular to the plane including the electrode; and A method for monitoring a bending position of an electrode tab, comprising: a step of measuring a distance from a cutting groove, which is an inner end of the cutting portion in the width direction, to the bending line, from an image acquired by the image acquisition device.

9. A method for monitoring the bending position of an electrode tab in claim 8, wherein, in the image acquisition step, light is irradiated to a mirror portion arranged on the shooting direction line of the camera in a direction intersecting the shooting direction, and the irradiated light reflected from the mirror portion is projected onto the non-photographic portion in parallel with the shooting direction.

10. A method for monitoring the bending position of an electrode tab, wherein, in the image acquisition step, the reflected light projected onto the non-conductive portion passes through the mirror portion and enters the camera.

11. In claim 8, the measuring step is a method for monitoring the bending position of an electrode tab, wherein the measuring step recognizes the position of the incision groove and the position of the bending line from the difference in contrast ratio distinguished by light reflected from the surface of the non-conductive part and incident on the camera in the image acquired by the camera, and calculates the distance between the recognized position of the incision groove and the position of the bending line.

12. A method for monitoring the bending position of an electrode tab, comprising: obtaining an average value of a plurality of predetermined distances calculated in claim 8; determining whether the average value deviates from the standard; and adjusting the widthwise position of a forming unit that performs bending processing to correct the average value if it is determined that the average value deviates from the standard.

Images