Electrode notching apparatus of secondary battery

Abstract

The present invention relates to an electrode notching device for a secondary battery that notches electrode tabs by irradiating a laser light onto an electrode film being transported in a roll-to-roll manner. The device includes a notching unit that notches electrode tabs by irradiating a laser light onto an electrode film according to a preset pattern. The notching unit is configured to include a laser module that cuts and notches electrode tabs by irradiating a laser light onto an electrode film (11), a drum that transports and supports the electrode film by rotating while in contact with the back surface of the electrode film moving from the loader unit to the rewinder unit, and a patternless jig in which a processing space is formed at an irradiation position where a laser light is irradiated from the laser module on the drum. This configuration eliminates the need to replace the jig due to changes in the pattern of the laser light for processing electrode tabs, and allows for the elimination of laser light focus errors by forming a flat section in the area of ​​the electrode film being processed by the laser light.

Description

Technology Field

[0001] The present invention relates to an electrode notching device for a secondary battery, and more specifically, to an electrode notching device for a secondary battery that notches an electrode tab by irradiating a laser while continuously conveying a film material, such as an electrode film of a secondary battery. Background Technology

[0002] A secondary battery is a rechargeable battery configured to repeatedly charge and discharge by allowing ions in the electrolyte to move between a positive electrode and a negative electrode insulated by a separator.

[0003] Electrodes such as the positive and negative electrodes of a secondary battery commonly comprise an electrode current collector and an electrode active material layer composed of an electrode active material coated on the electrode current collector. The electrode current collector can generally be processed into a sheet, thin plate, or foil form made of a metal with excellent conductivity, such as aluminum (Al) or copper (Cu).

[0004] The part where the electrode active material layer is not laminated on the electrode current collector and the electrode current collector is exposed is called the unladen part.

[0005] The process of forming an electrode tap by shearing the above-mentioned unsheared portion, particularly the end in the width direction of the electrode current collector, is called notching.

[0006] A notching device is a device that forms a terminal portion by cutting an electrode film, and a press method or a laser method is used for the exposed portion of the electrode film and a part of the area coated with active material.

[0007] For example, the following patent documents 1 and 2 disclose the configuration of an electrode notching device according to the prior art.

[0008] Meanwhile, an electrode notching device according to the prior art supplies and retrieves electrode films in a roll-to-roll manner, and notches electrode tabs by irradiating laser light onto the conveyed electrode film.

[0009] That is, the electrode notching device according to the prior art supplies an electrode film by the rotational movement of a supply roll provided in the supply section, and winds and recovers the electrode film cut and processed in the processing section by the rotational movement of a recovery roll provided in the recovery section.

[0010] And the electrode notching device according to the prior art includes a conveying unit that conveys an electrode film supplied from a supply roll to a recovery unit, and the conveying unit includes a roller unit formed in a drum shape that rotates while in contact with the back surface of the electrode film irradiated with laser light, and a pair of support units fixedly installed on both sides of the roller unit so as not to rotate.

[0011] Here, the roller section receives rotational force from the drive motor and rotates to transport the electrode film to the recovery section.

[0012] That is, the electrode notching device according to the prior art can transport the electrode film by using a roller section provided in the transport section during the process of transporting the electrode film along a plurality of rollers.

[0013] However, in the electrode notching device according to the prior art, as a drum-shaped transfer unit is applied, the distance between the laser module irradiating laser light and the electrode film increases as it moves upward and downward from the central part where the electrode film and the outer surface of the transfer unit come into contact.

[0014] In other words, there is a difference between the focal length of the laser light emitted from the laser module and the actual distance to the electrode film.

[0015] Therefore, in order to effectively respond to the difference in distance between the focal length and the actual electrode film, the diameter of the transfer section must be increased; however, if the diameter of the transfer section is increased, the overall size of the electrode notching device increases, and as the capacity of the drive motor to rotate the transfer section must be increased, there was a problem of increased manufacturing costs.

[0016] In addition, the electrode notching device according to the prior art had the problem of having to replace the pattern jig provided on the drum depending on the shape, size, and spacing of the electrode tab to be notched. Prior art literature

[0017] Republic of Korea Patent Registration No. 10-1958881 (Published March 15, 2019) Republic of Korea Patent Registration No. 10-2386086 (Published April 14, 2022) The problem to be solved

[0018] The objective of the present invention is to solve the problems described above by providing an electrode notching device for a secondary battery that can optimize the pattern jig of a drum provided in the area where a laser is irradiated.

[0019] Another objective of the present invention is to provide an electrode notching device for a secondary battery that can effectively compensate for focal length errors of laser light caused by the shape of the drum.

[0020] Another objective of the present invention is to provide an electrode notching device for a secondary battery that does not require modification of the pattern jig even when the shape, specifications, and spacing of the electrode tabs are changed, by applying an optimized pattern jig. means of solving the problem

[0021] To achieve the above-mentioned purpose, the electrode notching device of a secondary battery according to the present invention includes a notching unit that notches an electrode tab by irradiating a laser light onto an electrode film according to a preset pattern to notch an electrode tab by irradiating a laser light onto an electrode film that is transported in a roll-to-roll manner. The notching unit is characterized by including a laser module that cuts and notches an electrode tab by irradiating a laser light onto an electrode film (11), a drum that transports and supports the electrode film by rotating while in contact with the back surface of the electrode film moving from the loader unit to the rewinder unit, and a patternless jig in which a processing space is formed at an irradiation position where a laser light is irradiated from the laser module on the drum. Effects of the invention

[0022] As described above, according to the electrode notching device for a secondary battery of the present invention, by applying a patternless jig in which a square processing space is formed regardless of the pattern corresponding to the shape, specifications, and spacing of the electrode tab, the effect of eliminating replacement work due to pattern changes is obtained.

[0023] Furthermore, according to the present invention, by applying a pair of support rollers to a patternless jig to form a flat section in the area of ​​the electrode film processed by laser light, the effect of eliminating distance errors between the central part, the upper part, and the lower part of the drum is obtained.

[0024] In addition, according to the present invention, when notching an electrode tab, the precision is increased to improve product quality, and the working speed and workability can be maximized. Brief explanation of the drawing

[0026] FIG. 1 is a configuration diagram of an electrode notching device for a secondary battery according to a preferred embodiment of the present invention. FIG. 2 is a drawing illustrating the state of notching an electrode tab in an electrode film. FIG. 3 is a drawing illustrating a scanner device for notching an electrode tab in a notching section illustrated in FIG. 1. FIGS. 4 and FIGS. 5 are drawings illustrating patterns that change according to the shape, specifications, and spacing of the electrode tabs, respectively. Fig. 6 is a perspective view of the drum, FIGS. 7 and FIGS. 8 are cross-sectional views comparing the drum of an electrode notching device according to the prior art and the present embodiment, respectively. FIG. 9 is a perspective view of the patternless jig shown in FIG. 8, FIG. 10 is a flowchart illustrating, step-by-step, an electrode notching method using an electrode notching device of a secondary battery according to a preferred embodiment of the present invention. FIG. 11 is a drawing illustrating the process of notching an electrode tab using an overlay method. FIG. 12 is a diagram illustrating a detailed control method for the notching operation illustrated in FIG. 11. FIG. 13 is a drawing illustrating the pattern of laser light during notching in the top region of an electrode film for notching electrode tabs. FIG. 14 is a drawing illustrating the pattern of laser light during processing of the bottom region where a notch is formed in the electrode mold. Specific details for implementing the invention

[0027] Hereinafter, an electrode notching device for a secondary battery according to a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0029] FIG. 1 is a configuration diagram of an electrode notching device for a secondary battery according to a preferred embodiment of the present invention, FIG. 2 is a diagram illustrating a state of notching an electrode tab in an electrode film, and FIG. 3 is a diagram illustrating a scanner device for notching an electrode tab in a notching section shown in FIG. 1.

[0030] In the following, terms indicating directions such as 'left', 'right', 'forward', 'rear', 'upward', and 'downward' are defined as indicating the respective directions based on the state depicted in each drawing.

[0031] The electrode film (11) may be a single-sided electrode film with an electrode active material layer applied to only one side, but in this embodiment, a case is described in which the electrode tab of a double-sided electrode film having electrode active material layers formed on the front and rear sides (or the upper and lower sides) respectively is notched.

[0032] That is, in this embodiment, the electrode film (11) has an electrode active material layer (hereinafter abbreviated as 'active material layer') applied to the front and rear surfaces of the electrode body, respectively, and is manufactured so that only a portion of the electrode body is exposed without the active material layer being applied.

[0033] And, as shown in FIG. 2, an active material layer (12) is formed on each of the two sides of the electrode film (11), namely the first and second sides, and between each active material layer (12), a foil that functions as an electrode body using a metal material such as aluminum may be provided. In addition, an insulating film may be further provided between the foil and each active material layer (12).

[0034] Each electrode tab (14) is formed in a roughly square shape on an exposed portion of the electrode film (11) that is exposed to the outside of the active material layer (12), and the electrode notching device (10) performs notching processing to continuously form these electrode tabs (14).

[0035] Accordingly, the cutting line (CL) can be formed in a roughly square wave shape following an edge section (L1) (hereinafter referred to as the 'outer end') corresponding to the width of the electrode tab (14) and an edge section (L2) (hereinafter referred to as the 'inner end') of the cut exposed portion corresponding to the gap between the electrode tab (14).

[0037] As shown in FIGS. 1 to 3, the electrode notching device of a secondary battery according to a preferred embodiment of the present invention comprises a loader unit (20) that supplies an electrode film (11) wound in a roll shape, a notching unit (30) that notches an electrode tab by irradiating a laser light onto the supplied electrode film (11), a rewinder unit (40) that rewinds the electrode film (11) processed in the notching unit (30) back into a roll shape, and a control unit (50) that controls the operation of each device based on a preset processing process. The control unit (50) controls the operation of the notching unit (30) to notch an electrode tab (14) by irradiating the irradiation position of the laser light irradiated from the notching unit (30) according to a preset pattern (P).

[0038] The above processing process can notch the electrode tab (14) by receiving specifications and shape information such as the front-rear width of the electrode tab (14), the inner-outer height, and the pitch between the electrode tabs (14), and can notch the electrode tab (14) according to the set information.

[0039] In addition, the electrode notching device (10) of a secondary battery according to a preferred embodiment of the present invention may further include a tension cut unit (60) that stops the movement of the electrode film (11) when replacing the roll and separates the front and rear tension of the electrode film (11), and a position adjustment unit (70) that detects the transfer position of the electrode film (11) being transferred along a transfer path from the supply unit (11) to the recovery unit (12) side, and adjusts the transfer position of the electrode film (11) based on the detection result to prevent meandering.

[0040] In addition, the electrode notching device (10) of a secondary battery according to a preferred embodiment of the present invention may further include a master feeder (not shown in the drawing) that uses rotational force generated from a driving module, such as an electric motor or a pneumatic motor, to rotate a driving roller and transport the processed electrode film to the rewinder section (40).

[0041] That is, in the present embodiment, the electrode notching device (10) of the secondary battery can continuously transport the electrode film (11) without interruption in a roll-to-roll manner, and form an electrode tab (14) by shearing, i.e., cutting, one or both ends of the electrode film (11) in the width direction.

[0042] The loader section (20) includes a supply roll (21) that unwinds and supplies the electrode film (11) wound on the outer surface, and the rewinder section (30) may include a recovery roll (41) that winds and recovers the electrode film (11) after the notching process is completed. Thus, the electrode film (11) can be supplied, processed, and recovered in a roll-to-roll manner.

[0043] The notching section (30) functions to notch the electrode tab (14) by irradiating the electrode film (11) with laser light.

[0044] For example, the notching section (30) includes a laser module that performs notching processing by irradiating a laser light onto an electrode film (11) to cut an electrode tab, and the laser module may be provided with a laser oscillator that generates laser light, a pair of mirrors that rotate in the X-axis and Y-directions to adjust the direction of irradiation of the laser light, and a scanner device (31) that includes one or more lenses that adjust the shape, state, and diameter of the laser light, a beam dump, and a beam expander.

[0045] The scanner device (31) can rotate the pair of mirrors according to the processing process to irradiate laser light into a preset pattern (P).

[0046] For example, as the electrode tabs (14) are formed continuously in a roughly square shape, the pattern (P) can be formed in a roughly butterfly shape, as shown in FIG. 3.

[0047] The tension cut unit (60) normally provides rotational force to smoothly transport the electrode film (11) passing through the tension cut unit (60), and functions to separate the tension (tension) between the front and rear ends of the electrode film (11) passing through the tension cut unit (60) when damage or deformation of the electrode film (11) occurs or when replacing the roll.

[0048] Therefore, the tension cut unit (60) normally uses the driving force generated by the driving motor to transport the electrode film to the rewinder unit (40), and can stop transporting the electrode film (11) when the roll is replaced or when damage or deformation of the electrode film (11) occurs.

[0049] Accordingly, the operator can cut and remove the rear end of the electrode film (11) released from the existing roll and the front end of the new roll, or the damaged or deformed part of the electrode film (11), and connect the removed part using a separate connecting film.

[0050] These tension cut units (60) may be provided at the front or rear end of the notching section (30), or at the front and rear ends respectively.

[0051] The position adjustment unit (70) is provided at the front end of the above-mentioned laser module to adjust the position of the electrode film (11) and prevent meandering.

[0053] Next, the configuration of the drum and pattern jig will be described in detail with reference to FIGS. 4 to 9.

[0054] FIGS. 4 and FIGS. 5 are drawings illustrating patterns that change according to the shape, specifications, and spacing of the electrode tabs, respectively. FIGS. 6 is a perspective view of a drum, FIGS. 7 and FIGS. 8 are cross-sectional views comparing the drum of an electrode notching device according to the prior art and the present embodiment, respectively, and FIGS. 9 is a perspective view of the patternless jig shown in FIGS. 8.

[0055] Figure 4 illustrates a change in the shape of a pattern according to a change in length in the X-axis direction corresponding to the height of the electrode tab, and Figure 5 illustrates a change in the shape of a pattern according to a change in length in the Y-axis direction corresponding to the width of the electrode tab.

[0056] The pattern (P) can be formed into a butterfly shape in which two triangles having one intersection point (I) are arranged symmetrically or asymmetrically with respect to each other.

[0057] As shown in FIG. 4, the length (X) in the X-axis direction of the pattern (P) varies according to the height of the electrode tab (14) when the process speed of the scanner device (31) is the same. That is, the length (X) in the X-axis direction of the pattern (P) increases as the height of the electrode tab (14) increases, and decreases as the height of the electrode tab (14) decreases.

[0058] As shown in FIG. 5, the length (Y1) in the Y-axis direction of the outer end of the pattern (P) varies according to the process speed of the scanner device (31) when the width of the electrode tab (14) is the same. That is, the length (Y1) in the Y-axis direction of the outer end of the pattern (P) decreases as the process speed of the scanner device (31) is faster, and increases as the process speed of the scanner device (31) is slower.

[0059] And, in the pattern (P), the length (Y2) in the Y-axis direction of the inner end can vary according to the process speed of the scanner device (31) when the distance between the electrode tabs (14) is constant. That is, the length (Y2) in the Y-axis direction of the inner end of the pattern (P) decreases as the process speed of the scanner device (31) is faster, and increases as the process speed of the scanner device (31) is slower.

[0060] In this way, the shape of the pattern (P) and the length of each side can be changed in conjunction with the height and width of the electrode tab (14) and the process speed of the scanner device (31).

[0061] Therefore, conventionally, when the width of the electrode tab (14) changes, the process speed of the scanner device (31) can be adjusted to accommodate it, but it is difficult to increase or decrease the process speed of the scanner device (31) infinitely, and when the height of the electrode tab (14) exceeds the processing range of the pattern jig installed on the drum (32), the pattern jig had to be replaced.

[0062] Accordingly, in this embodiment, a patternless jig (80) is applied in which a processing space (81) forming a roughly square shape is formed so that electrode tabs of various pattern shapes and specifications can be processed without replacing the pattern jig.

[0063] To explain in detail, the notching section (30) is provided with a drum (32) that rotates in contact with the back surface of the electrode film (11) moving from the loader section (20) to the rewinder section (40) to transport and support the electrode film (11), and the drum (32) is provided with a patternless jig (80) in which a preset pattern (P) is formed at an irradiation position where laser light is irradiated from the laser module described above.

[0064] As shown in FIG. 6, the drum (32) includes a roller part (33) that rotates to transport the electrode film (11) and a pair of support parts (34) provided on both sides of the roller part (33), and a patternless jig (80) may be provided on one or both sides of the pair of support parts (34).

[0065] The support member (34) is fixedly installed on a fixed shaft (35) installed on an outer frame, and does not rotate even when the roller member (33) rotates around a rotating shaft installed on the fixed shaft (35), and functions to support the roller member (33) on both sides of the roller member (33).

[0066] And the support member (34) can be formed in a roughly cylindrical shape corresponding to the roller member (33) to move the electrode film (11) smoothly.

[0067] That is, the support member (34) may have a curvature corresponding to the outer surface of the roller member (33) so that the electrode film (11) can move smoothly while in contact with the back surface of the electrode film (11).

[0068] As such, as the outer surface of the drum (32) has curvature, the electrode notching device according to the prior art, as shown in FIG. 7, has a difference between the focal length of the laser light and the actual distance to the electrode film (11) depending on the diameter of the drum (32). That is, as the distance between the laser module irradiating the laser light and the electrode film (11) increases as it moves upward and downward from the center where the outer surface of the drum (32) contacts the electrode film (11), the laser light is defocused and an error occurs.

[0069] To compensate for such distance differences, the focal length of the laser beam must be compensated. However, precisely compensating for the laser beam's focal length is very difficult, and focusing errors can lead to defects in the product, such as uncut areas.

[0070] To resolve these problems, in this embodiment, as shown in FIGS. 8 and 9, a patternless jig (80) is applied in which a processing space (81) is formed in a roughly square shape on the support portion (34) of the drum (32).

[0071] The patternless jig (80) may include a housing (82) formed in a roughly cuboidal shape so as to be mounted on a support member (34) and having a processing space (81) provided on the front and inside, and a pair of support rollers (83) formed parallel to each other on the upper and lower front of the housing (82).

[0072] A processing space (81) is formed in the front center of the housing (82), and a pair of installation holes may be formed in the upper and lower parts of the processing space (81), each having a pair of support rollers (83) installed therein.

[0073] The processing space (81) transmits the laser light irradiated onto the electrode film (11) into the housing (82) to prevent damage to the surface of the support member (34) caused by the laser light, and can temporarily store fumes and dust generated as the electrode film (11) is cut by the laser light inside the housing (82).

[0074] And the processing space (81) can be connected to a dust collection unit (not shown in the drawing) that sucks in fumes and dust temporarily stored inside and discharges them to the outside.

[0075] This processing space (81) can be formed with a size corresponding to the processing process of the electrode tab (14) having the maximum size, so as to correspond to all sizes of the electrode tab (14) to be notched.

[0076] Each support roller (83) is formed in a roughly cylindrical shape, and a rotation axis can be connected to the center of each support roller (83). Thus, each support roller (83) can rotate around the rotation axis while in contact with the back surface of the electrode film (11) to support the electrode film (11) so that it can be transported smoothly.

[0077] Here, the shear of each support roller (83) is positioned to form a virtual plane identical to the top and bottom of the processing space (81).

[0078] Therefore, the electrode film (11) may include a planar section (FA) corresponding to the virtual plane described above as it passes between a pair of support rollers (83).

[0079] Therefore, in this embodiment, by irradiating a laser light onto an electrode film (11) placed in the planar section (FA) to notch the electrode tab (14), product defects caused by an error in the focal length of the laser light can be prevented.

[0080] Each of these support rollers (83) can be fixedly installed at the center of the rotation axis to prevent left-right movement due to the meandering of the electrode film (11).

[0081] And each side of each support roller (83) can be formed tapered or rounded so that the diameter becomes smaller towards both ends to prevent damage when in contact with the electrode film (11).

[0082] In this way, in the present embodiment, by using a pair of support rollers to support and transport the electrode film, friction with the electrode film is reduced, thereby preventing damage to the electrode film and increasing the usage time of the jig.

[0083] In addition, in this embodiment, the size of the processing space is set to correspond to the maximum size pattern, so that electrode tabs of various sizes and shapes can be accommodated using a single patternless jig, and size variation is also possible.

[0084] In addition, in this embodiment, processing stability is ensured by preventing shaking of the electrode film using a support roller provided on the upper part, and the internal condition can be easily checked by installing a viewing window on the side of the laser module and the notching part.

[0085] Meanwhile, the control unit (50) is provided as a central processing unit that controls the operation of each device provided in the electrode notching device (10).

[0086] The control unit (50) can control the electrode tab (14) to be notched in one operation by irradiating a laser light based on the processing process to optimize the shape and specifications of the pattern (P) for notching the electrode film (11).

[0087] To this end, the control unit (50) can set a unit length and a number of overlaps for performing the processing process, and control the operation of the scanner device (31) to repeatedly move the laser light back and forth in a linear fashion a preset number of times according to the set unit length and number of overlaps to notch the electrode tab (14) in a multipath manner.

[0088] In this way, the present invention can eliminate replacement work due to pattern changes by applying a patternless jig in which a square-shaped processing space is formed regardless of the pattern corresponding to the shape, specifications, and spacing of the drill tab.

[0089] In addition, the present invention can eliminate distance errors between the central part, the upper part, and the lower part of the drum by applying a pair of support rollers to a patternless jig to form a flat section in the area of ​​the electrode film processed by laser light.

[0090] In addition, the present invention can improve product quality by increasing precision during the notching process of electrode tabs, and can maximize work speed and workability.

[0092] Next, an electrode notching method using an electrode notching device for a secondary battery according to a preferred embodiment of the present invention will be described in detail.

[0093] FIG. 10 is a flowchart illustrating, step-by-step, an electrode notching method using an electrode notching device for a secondary battery according to a preferred embodiment of the present invention. FIG. 11 is a diagram illustrating a process of notching an electrode tab using an overlapping method, and FIG. 12 is a diagram illustrating a detailed control method for the notching operation illustrated in FIG. 11.

[0094] In step S10 of FIG. 10, when the power switch provided in the input section (not shown in the drawing) of the electrode notching device (10) of the secondary battery is turned on, the power supply section (not shown in the drawing) supplies power to drive each device.

[0095] Then, the control unit (50) initializes each device and executes a driving program stored in memory to prepare an operation for notching electrode tabs (14) on the electrode film (11).

[0096] Next, when the start button is operated by the operator, in step S12, the control unit (50) drives the master feeder to supply the electrode film (11) wound on the supply roll (21) to the position adjustment unit (70) and the notching unit (30) according to a preset processing process to notch the electrode tab (14), and controls the operation of each device to wind the processed electrode film (11) back onto the recovery roll (41).

[0097] To this end, in step S14, the control unit (50) sets the unit length, the travel interval, and the number of overlaps for performing the processing process, and calculates the propagation formula of the laser light using the set unit length, the travel interval, and the number of overlaps (S16). Then, the control unit (50) repeatedly moves the laser light in a straight line back and forth according to the calculated propagation formula and controls the operation of the scanner device (31) in a multipath manner to perform notching processing on the electrode tab (14) (S18).

[0098] That is, the control unit (50) irradiates the laser light while moving it by the set unit length as shown in FIG. 11, and repeats the process of moving it by the advance interval and the number of overlaps to cut the electrode tab (14) and perform notching processing.

[0099] Therefore, all sections of the electrode film where laser light is irradiated are overlapped using an overlapping method and cut by a single notching operation.

[0100] Here, the unit length, progression interval, and number of overlaps may be changed according to the shape and specification information of the electrode tab (14) included in the processing process in the electrode film (11), the irradiation intensity of the laser light, the processing speed of the laser light, and the driving speed of the electrode film (11).

[0101] Therefore, the control unit (50) can automatically calculate the length of each side of the pattern in which laser light is irradiated according to the set progress interval and the number of overlaps based on the set unit length.

[0102] For example, the number of overlaps in the notching operation can be set to 5, and the length and travel interval can be set to about 10 mm, indicated by one arrow as seen in Fig. 11.

[0103] So the control unit (50) can calculate a progression formula for moving the electrode film (11) about 30 mm forward and then about 10 mm forward for each unit length.

[0104] In FIG. 11, arrow A indicates a forward cutting operation in which the laser light is directed in the same direction as the travel direction of the electrode film (11), and arrow B indicates a reverse cutting operation in which the laser light is directed in the opposite direction to the travel direction of the electrode film (11).

[0105] And in order to satisfy the number of overlaps, the starting section C corresponding to area C in Fig. 11 can be cut by increasing the number of unit lengths without advancing until it reaches the maximum cutting length, i.e., about 30 mm.

[0106] When the maximum cutting length is reached, such as in area D, it can move forward by the advance interval for each cutting operation while returning by a size less than the set advance interval.

[0107] Next, a cutting operation is performed so that all sections, such as area E, satisfy an overlap count of 5.

[0108] Subsequently, in the last section corresponding to area F, just like in the starting section C, since the length for performing the cutting operation does not fall precisely, the cutting length can be adjusted to satisfy the above number of overlaps.

[0109] Here, the control unit (50) can calculate to minimize the number of direction changes when calculating the progress formula.

[0110] In other words, if the laser beam repeatedly moves forward and backward by a unit length, the number of direction changes increases, and this may lead to a decrease in cutting quality due to the direction change.

[0111] Accordingly, in this embodiment, it is preferable for the control unit (50) to calculate the progression formula by moving backward after reaching the maximum cutting length as shown in FIG. 11, and then moving forward by an additional amount equal to the progression interval during the next forward movement.

[0112] Meanwhile, in step S20, the control unit (50) can set an offset section to prevent the deterioration of the cutting quality of the product due to the acceleration or deceleration of the galvanometer applied to the scanner device (31) after forward or backward movement as shown in FIG. 12, and control the scanner device (31) to stop the irradiation of the laser light and move further forward or backward in the set offset section.

[0113] That is, in FIG. 12, region G is the offset section in which the laser light is advanced by three unit lengths, the irradiation of the laser light is stopped, and the scanner device (31) is further advanced.

[0114] So the control unit (50) can control the scanner device (31) to move further by an offset interval than the calculated forward movement distance, i.e., three unit lengths, and to turn off the laser light during a preset laser off early interval that is shorter than the offset interval.

[0115] And when the control unit (50) changes the direction to move the laser light backward after moving it forward, it can turn off the laser light during a laser ON Delay period that is preset to be shorter than the offset period, and turn on the laser light when it is out of the laser ON Delay period and then control it to move backward by a calculated distance, i.e., two unit lengths.

[0116] Additionally, the control unit (50) can control the scanner device (31) to move further by the offset section shown as area H in FIG. 12 after moving the laser light backward, and to turn off the laser light in the laser early off section.

[0117] Afterwards, the control unit (50) can control the laser beam to move forward or backward again, and to repeat the above process.

[0118] For example, FIG. 13 is a diagram illustrating the pattern of laser light during notching in the top region where an electrode tab is notched in an electrode film, and FIG. 14 is a diagram illustrating the pattern of laser light during processing in the bottom region where a notch is formed in an electrode film.

[0119] As shown in FIG. 13, the laser light pattern in the above top region may include a shape inclined toward the right front, a shape inclined toward the left and right front, and a shape inclined toward the right rear as the laser light is irradiated in an overlapping manner.

[0120] As shown in FIG. 14, the laser light pattern in the bottom region may include a shape inclined toward the left and right front relative to the center line and a shape inclined toward the right and left front.

[0121] Meanwhile, as shown in FIGS. 13 and 14, the control unit (50) can control the laser light to stop at a preset stop position (PS) when the supply roll (21) or the return roll (41) is replaced or when the notching process of the electrode tab (14) is finished, so that it can be used as a reference position for the next notching process.

[0122] Therefore, at step S22, the control unit (50) checks whether the notching process of the entire electrode tab is completed, and if it is not completed, proceeds to step S18 and repeats the subsequent process.

[0123] If the inspection result of step S22 is complete, the control unit (50) controls the transfer of the electrode film (11) and the movement of the scanner device (31) to stop when the stop position (PS) is reached (S24).

[0124] Then, in step S26, the control unit (50) checks whether the power switch is turned off when the notching process is completed, and repeats steps S12 through S26 until the power switch is turned off.

[0125] Meanwhile, if the power switch is turned off as a result of the inspection in step S26, the control unit (50) stops and terminates the operation of each device provided in the electrode notching device (10).

[0126] Through the process described above, the present invention can notch electrode tabs using an overlapping method by moving the laser light back and forth in a straight line without stopping, according to the unit length, travel interval, and number of overlaps set based on the processing process.

[0127] In addition, since the present invention enables ablation using a single scanner device, costs during manufacturing operations can be reduced.

[0128] In addition, the present invention can track a path processed once exactly as it is while driving, and can also change the processing process while driving.

[0129] In addition, the present invention minimizes processing time and pattern size by minimizing overlapping paths for each section, and can prevent laser light focusing errors that may occur in roll-to-roll equipment.

[0130] In addition, the present invention can prevent the deterioration of cutting quality caused by direction changes by calculating a propagation formula that minimizes the number of direction changes of the laser light using the propagation interval and the number of overlaps of the laser light.

[0131] In addition, the present invention can enable laser processing in a path where the scanner device always moves at a constant speed by considering the acceleration / deceleration path of the scanner device itself that may occur due to a change in the movement direction of the scanner device, and by setting an additional processing length offset, a laser on delay, and a laser early off section.

[0132] Although the invention made by the inventors has been specifically described according to the above embodiments, the present invention is not limited to the above embodiments and can be modified in various ways without departing from the gist thereof. Industrial applicability

[0133] The present invention is applied to a secondary battery electrode notching device technology that eliminates the task of replacing a jig due to changes in the pattern of laser light for processing electrode tabs and eliminates laser light focus errors by forming a flat section in the area processed by laser light on the electrode film. Explanation of the symbols

[0134] 10: Electrode notching device for secondary batteries 11: Electrode film 12: Electrode active material layer 14: Electrode tab 15: Insulating film 20: Loader section 21: Supply roll 30: Notching section 31: Scanner device 32: Drum 33: Roller section 34: Support member 35: Fixed shaft 40: Rewinder 41: Recovery Roll 50: Control unit 60: Tension Cut Unit 70: Position adjustment unit 80: Patternless Jig 81: Processing space 82: Housing 83: Support roller FA: Flat section CL: Cutting line PS: Stop position L1: Edge section of the electrode tab L2: Edge section of the exposed part X: Length of the pattern along the X-axis Y1,Y2: Length of the pattern along the Y-axis

Claims

Claim 1 An electrode notching device for a secondary battery that notches an electrode tab by irradiating a laser light onto an electrode film transported in a roll-to-roll manner, comprising a notching unit that notches an electrode tab by irradiating a laser light onto the electrode film according to a preset pattern, wherein the notching unit comprises a laser module that cuts and notches the electrode tab by irradiating a laser light onto the electrode film, a drum that transports and supports the electrode film by rotating while in contact with the back surface of the electrode film moving from the loader unit to the rewinder unit, and a patternless jig having a processing space formed at an irradiation position where the laser light from the laser module is irradiated on the drum, wherein the patternless jig comprises a housing having the processing space formed on its front surface and inside, and a pair of support rollers installed parallel to the upper and lower portions of the processing space, wherein the processing space is formed to correspond to all specifications of the electrode tab to be notched, and is formed to correspond to the processing process of an electrode tab having the maximum specifications, and transmits the laser light irradiated onto the electrode film into the interior of the housing, and the generated as the electrode film is cut by the laser light A secondary battery electrode notching device characterized by temporarily storing fumes and dust inside the housing, and the electrode film forming a planar section corresponding to a virtual plane connecting the upper and lower parts of the processing space while passing between the pair of support rollers to prevent product defects caused by errors in the focal length of the laser light. Claim 2 An electrode notching device for a secondary battery according to claim 1, comprising a loader unit for supplying an electrode film wound in a roll shape, a rewinder unit for winding and recovering the electrode film processed in the notching unit in a roll shape, and a control unit for controlling the operation of each device based on a preset processing process, wherein the control unit sets a unit length and a number of overlaps for performing the processing process, and controls the operation of the notching unit to notch the electrode tab by repeatedly moving a laser beam in a straight line back and forth according to the set unit length and number of overlaps, and wherein the processing process receives specification and shape information including the front-rear width, inner-outer height, and spacing information between electrode tabs of the electrode tab to be processed, and notches the electrode tab according to the set information. Claim 3 An electrode notching device for a secondary battery according to paragraph 2, wherein the drum comprises a roller portion that rotates to transport an electrode film and a pair of support portions provided on both sides of the roller portion, and the patternless jig is provided on one or both sides of the pair of support portions. Claim 4 delete Claim 5 delete Claim 6 An electrode notching device for a secondary battery, characterized in that, in any one of claims 1 to 3, each support roller is fixedly installed at the center of each rotation axis to prevent flow due to the meandering of the electrode film, and each side of each support roller is formed to be tapered or rounded so that the diameter decreases toward both ends. Claim 7 An electrode notching device for a secondary battery according to claim 6, characterized in that the processing space is connected to a dust collection unit that sucks in fumes and dust temporarily stored inside and discharges them to the outside.

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