DE202022100080U1 - Electrode cutting device - Google Patents

Abstract

1 . A cutting device for an electrode, wherein the cutting device has a cutting tool configured to irradiate a surface of an electrode unwound from an electrode roll with a laser beam, whereby the irradiated part is cut by being vaporized or melted.

Description

REFERENCE TO RELATED APPLICATION

The present application claims priority to the Korean provisional patent application filed on Jan. 8, 2021 with the application number 10-2021-0002905 , which is incorporated by reference into the present application.

TECHNICAL AREA

The present invention relates to a cutting device for an electrode, and more particularly to a cutting device for an electrode with which the electrode is cut by irradiating a laser beam instead of using a mechanical cutter. In a unit cell made by stacking electrodes and separators, the cutting device for an electrode according to the present invention can also be used for cutting the separator.

BACKGROUND OF THE INVENTION

Unlike primary batteries, secondary batteries are rechargeable, and they can be more compact in size and higher in capacity than primary batteries. Therefore, studies on secondary batteries are currently being carried out. With the development of technology and the growing demand for mobile devices, the need for secondary batteries as power sources is increasing rapidly.

Such a secondary battery is configured such that an electrode assembly is accommodated in a battery case (a bag, a can, or the like). The electrode assembly mounted in the battery case can be repeatedly charged and discharged due to its structure in which a positive electrode/a separator/a negative electrode are stacked. The electrode assembly is manufactured by various methods, but usually used like a stacking method in which individual unit cells 4 are first manufactured and then a plurality of unit cells 4 are stacked to manufacture the electrode assembly.

In 1A A manufacturing of a unit cell 4 is schematically illustrated, wherein a method for manufacturing the unit cell 4 is configured such that a positive electrode 1, an upper separator 3a, a negative electrode 2 and a lower separator 3b are arranged in the order mentioned from top to bottom arranged below and wound in roll forms are continuously unwound and fed (at this time, stacking positions of the positive and negative electrodes may change).

The separators 3 (3a, 3b) are continuously fed without interruption; the negative electrode 2 unwound from an electrode roll (a negative electrode) is fed between the upper separator 3a and the lower separator 3b; and the positive electrode 1 is fed from an electrode roller 1c (a positive electrode) to a top of the upper separator 3a.

Here, the separators 3 are continuously fed without being cut, while the positive electrode 1 and the negative electrode 2 are cut to a predetermined size with cutters 6 and 7, respectively, and then loaded and fed.

The positive electrode 1 and the negative electrode 2 are stacked in pairs on the upper side and the lower side with the upper separator 3a in between, with adjacent positive electrode 1 and adjacent negative electrode 2 being arranged at predetermined intervals.

That is, the separators 3 are continuously joined, but the negative electrode 2 and the positive electrode 1 pass through a laminator 9 while being spaced apart from an adjacent negative electrode 2 and an adjacent positive electrode 1 by a certain distance, respectively. The laminator 9 applies heat and pressure to achieve adhesion at positions where the negative electrodes 2 and the positive electrodes 1 are in contact with the separators 3 .

The positive electrode 1 and the negative electrode 2 pass through the laminator 9 while being adhered to the separator 3 and then pass through pressure rollers 5 . Then, the separator 3 is divided between the adjacent positive electrode 1 and a positive electrode 1 (between the negative electrode and the negative electrode), so that individual unit cells 4 are formed.

A cutter 7 for cutting the positive electrode 1, a cutter 6 for cutting the negative electrode 2, and a cutter 8 for cutting the separators 3 all perform cutting by applying pressure from positions above and below the electrodes or separators.

However, as in 1B is shown, the unfolding of the positive electrode 1 before As cutting shows, a positive-electrode ridge 1a and a shoulder line 1b have been generated in the positive electrode 1 (and the negative electrode) with a notching process, and therefore a cutting position had to be determined accurately.

Also, in the manufacturing process for the unit cell 4, the positive electrode 1 and the negative electrode 2 are first cut, and then the individually cut electrodes 1 and 2 are laid, but this can be done in a continuous process. Faster cutting may be required here when using the continuous process. However, the mechanical cutting method is limited in cutting time.

In addition, in the prior art in which the cutting is performed, a pressure is continuously applied to tips of the cutters 6, 7 and 8. Therefore, separation occurs from a cut surface of the electrode (or the separator) when the tips of the cutters become blunt.

DESCRIPTION OF THE INVENTION

TECHNICAL TASK

In order to solve the problem described above, it is a primary object of the present invention to provide a cutting device for an electrode in which cutting is performed by laser irradiation instead of physical contact. Thus, cutting can be performed faster and more accurately, and separation at a cut surface of an electrode can be avoided.

In addition, the cutting device for an electrode according to the present invention can also be used for cutting a separator and a positive and a negative electrode.

TECHNICAL SOLUTION

In order to achieve the above object, the present invention provides a cutting device for an electrode.

A cutting method for an electrode is an electrode cutting method including: an electrode supplying step in which an electrode, which is paid out from an electrode roll, is moved to a cutting tool; an electrode speed setting step in which a moving speed of the electrode is set before the electrode unwound from the electrode roll arrives at the cutting tool; and an electrode cutting step in which the electrode arriving at a cutting position is cut by the cutting tool, wherein during the electrode cutting step the cutting tool irradiates a surface of the electrode with a laser beam so that the electrode is cut by being vaporized or melted.

A cutting device for an electrode according to the present invention is an electrode cutting device having a cutting tool configured to irradiate a surface of an electrode unwound from an electrode roll with a laser beam, wherein the irradiated part is cut by evaporating or is melted.

The cutting device according to the invention has a buffer unit which is arranged between the electrode roll and the cutting tool so that the electrode unwound from the electrode roll is fed to the cutting tool at a predetermined speed.

The buffer unit has upper rollers arranged on a relatively upper side and lower rollers arranged on a relatively lower side, the electrode being arranged to alternately run over an upper and a lower roller, the slide the upper and/or the lower rollers in an up and down direction and adjust a moving speed of the electrode while the electrode moves and rides over the upper and the lower rollers.

At least two or more upper and lower rollers are arranged such that the lower roller is between adjacent upper rollers and the upper roller is between adjacent lower rollers.

The buffer unit further includes entry rollers configured to load the electrode before it arrives at the upper and lower rollers, the entry rollers being located at a top and a bottom of the electrode, respectively, so that the electrode is between the entry rollers runs through.

The buffer unit further includes exit rollers configured to take out the electrode that has passed over the upper and lower rollers, the exit rollers being located respectively at the top and bottom of the electrode so that the electrode is between the exit rollers.

Stopping and rotating of the input and output rollers can be adjusted depending on a cutting speed of the cutting tool.

The buffer unit has a load cell, and the electrode is arranged to pass over the load cell, the load cell detecting a change in a load applied thereto.

The cutting tool emits the laser beam through a telecentric f-theta lens.

Here the cutting tool etches the electrode with a long pulse laser beam having a pulse width of 10 ns or more and then etches the rest of the electrode with a short pulse laser beam having a pulse width of less than 10 ns and then cuts the electrode.

The cutting tool has an optical device configured to optically monitor a position irradiated with the laser beam, and the optical device can select and adjust a cutting position.

BENEFICIAL EFFECTS

In the present invention having the technical features described above, a cutting process is performed on an electrode (and/or a separator) by laser irradiation without physical contact, whereby the cutting process is performed faster and more precisely.

In addition, abrasion by contact with a cutter does not occur, and thus occurrence of separation at a cut surface can be suppressed.

In addition, a moving speed of the electrode unwound from an electrode roll can be controlled by a buffer unit, so that stable cutting is achieved.

The buffer unit can adjust a moving length of the electrode by raising and lowering the upper and lower rollers, and thus can adjust the moving speed. Multiple upper and lower rollers are provided, respectively, and pressure is applied from a large area. This can prevent deformation from the pressure generated when the upper and lower rollers are raised and lowered.

The stopping and rotating of each input and output roller can be adjusted depending on a cutting speed of a cutting tool, so that the moving speed of the electrode can be more efficiently controlled.

In addition, a load cell provided in the buffer unit detects a change in a load of the electrode and a reciprocation of the electrode. The collected information can be used to control the raising and lowering of the upper and lower rollers and the turning and stopping of the input and output rollers.

The cutting tool is configured to etch the electrode with a long pulse laser beam having a pulse width of 10 ns or more and then etch the remainder of the electrode with a short pulse laser beam having a pulse width of less than 10 ns has, and then cuts the electrode. Thereby, a spatter loss in laser irradiation is minimized, and occurrence of slag on a cut surface can be minimized.

In addition, the cutting tool has an optical device for optically monitoring a position irradiated with the laser beam, and the cutting position can be optimally selected by the optical device.

character list

• 1A Fig. 12 is an illustration schematically showing manufacturing of a unit cell.
• 1B Fig. 12 is a diagram showing a state where a positive electrode is unfolded.
• 2 Fig. 12 is an illustration schematically showing a cutting device according to the present invention.
• 3A Fig. 12 is an illustration showing a state in which a long pulse laser beam is emitted from a cutting tool.
• 3B Fig. 12 is a diagram showing a state in which a short pulse laser beam is emitted from a cutting tool and upper and lower rollers provided in a buffer unit are raised and lowered.
• 4 12 is a diagram showing a state in which an optical device is additionally arranged in the vicinity of the cutting tool.

MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. However, the present invention can be embodied in various different forms and is not limited to the embodiments described herein.

The part irrelevant to the description is omitted for the sake of clarity of the present invention, and the same or similar elements are denoted by the same reference numbers throughout the description.

In addition, terms or words used in this specification and claims should not be interpreted restrictively as ordinary or dictionary-based meanings, but should be interpreted as meanings and terms that are within the scope of the present invention based on principle that an inventor can expertly define the term to best describe and explain his invention.

The present invention relates to a cutting device for an electrode (i.e., a positive and a negative electrode) which can be used for manufacturing a unit cell 4 in which electrodes 1 and 2 are placed between a lower separator 3b and an upper separator 3a and above the upper separator 3a are stacked.

Thus, instead of the cutter 7 for cutting the positive electrode 1 and the cutter 6 for cutting the negative electrode 2 of the present invention, the cutting device 1A to be provided. In addition, the cutter 8 that cuts the separators 3a and 3b can be replaced with the cutting tool of the present invention.

That is, the cutters 6, 7 and 8 are from the configuration of 1A removed and a cutting tool 10 according to the present invention can be provided. In addition, a buffer unit 30 may be provided in the cutting tool 10 used in place of the cutters 6 and 7 cutting the electrode.

FIRST EMBODIMENT

The present invention provides a cutting device for an electrode as a first embodiment. The cutting device provided in the first embodiment is a device for cutting an electrode to a predetermined size, and has a cutting tool 10 which irradiates a surface of an electrode 1 unwound from an electrode roll 1C with a laser beam. The irradiated part is cut by being vaporized or melted.

The laser beam emitted from the cutting tool 10 can be emitted with a sufficient output so that cutting can be performed as evaporation or melting that occurs when the separator and the electrode (a positive and/or a negative electrode) are irradiated.

The cutting tool 10 can emit the laser beam through a telecentric f-theta lens. The f-theta telecentric lens is a lens in which the laser beam is made to shine by additionally using an optical system, and main rays of light always strike a cut surface vertically regardless of a radiation angle. Thus, the energy of the laser beams can be focused more efficiently than with other types of lenses.

2 Fig. 12 is an illustration schematically showing the cutting device according to the present invention. 3A FIG. 12 is a diagram showing a state in which a long pulse laser beam is emitted from the cutting tool 10. FIG. 3B 12 is a diagram showing a state in which a short pulse laser beam is emitted from the cutting tool 10 and upper rollers 31 and a lower roller 32 provided in a buffer unit 30 are raised and lowered. 4 FIG. 12 is a diagram showing a state in which an optical device 50 is additionally arranged in the vicinity of the cutting tool 10. FIG.

In the accompanying drawings, in the cutting device provided in the first embodiment, the buffer unit 30 is arranged between the electrode roll 1c and the cutting tool 10 so that the electrode 1 unwound from the electrode roll 1c is fed to the cutting tool 10 with an unwinding device 20 which is operated at a predetermined speed.

The buffer unit 30 has upper rollers 31 arranged on a relatively upper side and lower rollers 32 arranged on a relatively lower side.

As shown, at least two or more upper rollers 31 and lower rollers 32 can be arranged so that lower roller 32 is located between adjacent upper rollers 31 and the upper roller 31 is located between adjacent lower rollers 32.

In addition, the electrode 1 is arranged to run over the upper roller 31 and the lower roller 32 alternately. As the electrode 1 moves and rides over the upper rollers 31 and the lower rollers 32, the upper rollers 31 and/or the lower rollers 32, preferably all the upper rollers 31 or all the lower rollers 32, slide in an up and down direction, as in 3B is shown and they adjust a moving speed of the electrode 1 . That is, adjusting mobility here means that the upper rollers 31 and the lower rollers 32 are raised or lowered, and a moving distance of the electrode 1 is lengthened or shortened, and thereby a moving amount and moving speed when reaching the cutting tool 10 are adjusted.

In addition, the buffer unit 30 may further include entry rollers 33 for loading the electrode 1 before reaching the upper rollers 31 and the lower rollers 32, and exit rollers 34 for taking out the electrode 1 after it has passed over the upper rollers 31 and the lower rollers 32 .

The input rollers 33 are each arranged on a top and a bottom of the electrode 1 so that the electrode 1 passes between them, and the exit rollers 34 are respectively arranged on a top and bottom of the electrode 1 so that the electrode 1 passes between them.

Thus, the electrode 1 slid by the input rollers 33 and the output rollers 34 can be fixed therebetween, and therefore the stopping and rotating of each of the input rollers 33 and the output rollers 34 are controlled depending on the cutting speed of the cutting tool 10. Accordingly, in addition, the moving speed of the electrode 1 can be adjusted.

In addition, the buffer unit 30 has a load cell 35 . The load cell 35 is provided in the form of a roller and is arranged so that the electrode 1 can pass over the load cell 35 . The load cell 35 detects a change in a load applied thereto (by the voltage generated when the electrode 1 moves). Thus, when the load (or pressure) applied to the load cell 35 is measured, an occurring vibration of the electrode 1 can be detected. In addition, with this detected information, the sliding or rotating of the upper rollers 31, the lower rollers 32, the input rollers 33 and the output rollers 34 can be controlled. Accordingly, the electrode 1 can be held in a flat shape when it arrives at the cutting tool 10, and thereby stable cutting can be achieved.

In the present invention, the cutting process performed by the cutting tool 10 can be divided into two steps. That is, as in 3A As shown, the cutting tool 10 can etch the electrode 1 with a long-pulse laser beam having a pulse width of 10 ns or more, and the cut surface (or the etched surface) can then be etched with a short-pulse laser beam having a pulse width of less than 10 ns. A smooth cut surface can thereby be obtained. That is, cutting is performed with a laser beam having a relatively high power, and then cutting is completed by irradiating again with a laser beam having a relatively low power. This minimizes spatter generated during cutting and waste generated on the cut surface.

Also, in the first embodiment, the cutting device may include an optical device 50 for optically monitoring the position irradiated with the laser beam. As in 4 As shown, the optical device 50 can be arranged to optically monitor a site where cutting is being performed, select the cutting position, and provide information needed to adjust the cutting position.

The electrode 1 is cut with the cutting device described above, and after cutting, its segments are stacked in a predetermined number and stored in a magazine 40. FIG. Alternatively, as in 1A is shown, the insertion of the electrode 1 on the separator or between the separators takes place directly after cutting.

The first embodiment has been described for the electrode. However, it can also be used for cutting the separator when manufacturing unit cells if there are no problems in passing over the upper rollers 31, the lower rollers 32, the input rollers 33 and the output rollers 34.

SECOND EMBODIMENT

Also provided is a cutting method for an electrode which can be used for the cutting device provided in the first embodiment.

The electrode cutting method includes an electrode feeding step, an electrode speed adjusting step, and an electrode cutting step.

In the electrode supplying step, an electrode roll (a positive electrode roll or a negative electrode roll) is unwound, and an unwound electrode (a positive or a negative electrode) is moved to a cutting tool 10 .

Also, in the electrode speed setting step, a moving speed of an electrode 1 is set before the electrode 1 arrives at the cutting tool 10 during the execution of the electrode feeding step. This step can be performed by driving or controlling the buffer unit 30 described above.

In the electrode cutting step, the electrode 1 arriving at a cutting position is cut by the cutting tool 10 . In this step, the cutting tool 10 irradiates the surface of the electrode with a laser beam, so that the electrode is cut by being vaporized or melted.

In the present invention having the technical features described above, a cutting process is performed on an electrode (and/or a separator) by laser irradiation without physical contact, and the cutting process is performed faster and more precisely.

In addition, abrasion by contact with a cutter does not occur, and thus occurrence of separation at a cut surface can be suppressed.

In addition, a moving speed of the electrode 1 unwound from an electrode roll can be controlled by the buffer unit 30, so that stable cutting is achieved.

The buffer unit 30 can adjust a moving length of the electrode by raising and lowering upper rollers 31 and lower rollers 32, and thus can adjust the moving speed. A plurality of upper rollers 31 and lower rollers 32 are provided respectively, and pressure is applied from a large area. Thereby, deformation by the pressure generated when the upper rollers 31 and the lower rollers 32 are raised and lowered can be avoided.

The stopping and rotating of each input roller 33 and each output roller 34 can be adjusted according to the cutting speed of the cutter, so that the moving speed of the electrode can be controlled more efficiently.

In addition, a load cell 35 provided in the buffer unit detects a change in a load of the electrode and a reciprocating movement of the electrode. Using the detected information, the raising and lowering of the upper rollers 31 and the lower rollers 32 and the rotating and stopping of the input rollers 33 and the output rollers 34 can be controlled.

The cutting tool 10 is configured to etch the electrode with a long pulse laser beam having a pulse width of 10 ns or more and then etch the remainder of the electrode with a short pulse laser beam having a pulse width of less than 10 ns, and then cuts the electrode. Thereby, a spatter loss in laser irradiation is minimized, and the occurrence of slag on a cut surface can also be minimized.

In addition, the cutting device has an optical device 50 for optically monitoring a position irradiated with the laser beam, and the cutting position can be optimally selected by means of the optical device 50 .

Although the present invention has been described with reference to specific embodiments and drawings, the present invention is not limited thereto and various changes and modifications can be made by those skilled in the art to which the present invention pertains within the technical spirit of the present invention and the appropriate scope of protection of the appended claims.

Reference List

10

cutting tool

20

unwinding device

30

buffer unit

31

upper roll

32

bottom roll

33

entrance role

34

exit roll

35

load cell

40

magazine

50

optical device

QUOTES INCLUDED IN DESCRIPTION

This list of the documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• KR 1020210002905 [0001]

Claims (11)

1 . A cutting device for an electrode, wherein the cutting device has a cutting tool configured to irradiate a surface of an electrode unwound from an electrode roll with a laser beam, whereby the irradiated part is cut by being vaporized or melted. cutting device claim 1 comprising a buffer unit disposed between the electrode roll and the cutting tool so that the electrode unwound from the electrode roll is fed to the cutting tool at a predetermined speed. cutting device claim 2 wherein the buffer unit comprises an upper roller arranged on a relatively upper side and a lower roller arranged on a relatively lower side, wherein the electrode is arranged to alternately span the upper roller and the lower roller runs, and wherein the upper and/or lower roller slides in an up and down direction and adjusts a moving speed of the electrode as the electrode moves and runs over the upper roller and the lower roller. cutting device claim 3 wherein at least two or more upper and lower rollers are arranged such that the lower roller is between adjacent upper rollers and the upper roller is between adjacent lower rollers. cutting device claim 3 wherein the buffer unit further comprises entry rollers configured to insert the electrode before it arrives at the upper and lower rollers, the entry rollers being arranged at a top and a bottom of the electrode so that the electrode passes through. cutting device claim 5 wherein the buffer unit further comprises exit rollers configured to take out the electrode that has passed over the upper and lower rollers, and the exit rollers are arranged at the top and bottom of the electrode so that the electrode passes between the exit rollers . cutting device claim 6 , stopping and rotating each of the input and output rollers being adjusted depending on a cutting speed of the cutting tool. cutting device claim 6 wherein the buffer unit includes a load cell and the electrode is arranged to pass over the load cell, the load cell detecting a change in a load applied thereto. cutting device claim 1 , where the cutting tool emits the laser beam through a telecentric f-theta lens. cutting device claim 1 wherein the cutting tool etches the electrode with a long-pulse laser beam having a pulse width of 10 ns or more, and then etches the rest of the electrode with a short-pulse laser beam having a pulse width of less than 10 ns, and thereafter the electrode cuts. cutting device claim 1 wherein the cutting tool includes an optical device configured to optically monitor a position irradiated with the laser beam, the optical device selecting and adjusting a cutting position.

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