Laser notching device

Abstract

The laser notching device according to an embodiment of the present invention can notch an electrode tab on an electrode sheet. The laser notching device includes: a laser unit that irradiates a laser beam onto the electrode sheet; a rotating drum that contacts the electrode sheet and moves the electrode sheet; a fixed drum located on one side in the axial direction of the rotating drum; and a scrap suction unit provided in the fixed drum and configured to suck scrap cut from the electrode sheet by the laser beam.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2022 - 0065686, filed on May 27, 2022, and all the contents disclosed in the literature of the Korean patent application are incorporated herein by reference in their entirety.

[0002] The present invention relates to a laser notching device, and more particularly, to a laser notching device for notching electrode tabs on an electrode sheet.

Background Art

[0003] Generally, types of secondary batteries include nickel - cadmium batteries, nickel - metal hydride batteries, lithium - ion batteries, and lithium - ion polymer batteries. Such secondary batteries are used not only in small products such as digital cameras, P - DVDs, MP3Ps, mobile phones, PDAs, portable game devices, power tools, and e - bikes, but also in large products that require high power, such as electric vehicles and hybrid vehicles, as well as in power storage devices for storing surplus generated power and new renewable energy and backup power storage devices.

[0004] Secondary batteries are classified into pouch type, can type, etc., according to the material of the case that houses the electrode assembly. In particular, the can type is manufactured by housing the electrode assembly in a rigid can, and a secondary battery with a cylindrical can can be named a cylindrical secondary battery.

[0005] Generally, a can-type secondary battery, particularly a cylindrical secondary battery, includes a jelly roll type electrode assembly. The jelly roll type electrode assembly may be manufactured by processing an electrode sheet, on which an electrode active material is coated on a sheet-shaped current collector, into a desired form by a notching process and then winding it together with a separator. The notching process may be performed by physically cutting the electrode using a press die or by irradiating a laser for cutting.

[0006] Particularly, in the case of the notching process using a laser, there is a risk that the laser may be disturbed by foreign matters such as scraps cut from the electrode sheet or dust generated during the cutting process. In order to prevent such a risk, a laser notching device capable of quickly and reliably removing the scraps and foreign matters is required.

Summary of the Invention

Problems to be Solved by the Invention

[0007] One problem to be solved by the present invention is to provide a laser notching device capable of quickly and reliably removing scraps and foreign matters.

Means for Solving the Problems

[0008] The laser notching device according to an embodiment of the present invention can notch an electrode tab on an electrode sheet. The laser notching device includes a laser unit that irradiates a laser beam onto the electrode sheet; a rotating drum that contacts the electrode sheet and moves the electrode sheet; a fixed drum located on one side in the axial direction of the rotating drum; and a scrap suction unit provided in the fixed drum that sucks scraps cut from the electrode sheet by the laser beam.

[0009] The laser notching device can further include a mask jig provided on the fixed drum and facing the laser unit with the electrode sheet interposed therebetween. The scrap suction portion can be located behind the mask jig with respect to the moving direction of the electrode sheet.

[0010] The scrap suction portion can be located between the mask jig and the lowermost end portion of the fixed drum in the circumferential direction of the fixed drum.

[0011] The fixed drum and the rotating drum may be arranged to have the same axis.

[0012] The outer diameter of the fixed drum and the outer diameter of the rotating drum may correspond to each other.

[0013] The fixed drum can face a part of the edge side in the width direction of the electrode sheet in its radial direction.

[0014] A mounting groove for mounting the scrap suction portion may be formed in the fixed drum.

[0015] The scrap suction portion can include a suction hole extending along the circumferential direction of the fixed drum.

[0016] The laser notching device can further include a discharge portion connected to the scrap suction portion for discharging the scrap sucked into the scrap suction portion.

[0017] An extension portion extending in the axial direction of the fixed drum and inserted into the rotating drum may be formed in the fixed drum.

[0018] The rotating drum can surround the extension portion and rotate with respect to the extension portion.

[0019] A discharge passage for guiding the scrap sucked into the scrap suction portion may be formed in the extension portion.

Advantages of the Invention

[0020] According to a preferred embodiment of the present invention, since the scrap suction part is attached to the fixed drum, the suction of the scrap can be made rapid and reliable as compared with the case where the scrap suction part is separately arranged outside the fixed drum.

[0021] Also, since the scrap suction part is attached to the fixed drum, the scrap suction part can suck and remove not only the scrap but also foreign matters such as dust generated during the notching process of the electrode sheet.

[0022] Also, the scrap suction part can be positioned between the mask jig and the lowermost end part of the fixed drum with respect to the circumferential direction of the fixed drum. Thereby, the scrap can be quickly sucked into the scrap suction part before the scrap droops downward.

[0023] Also, the suction holes of the scrap suction part may be extended along the circumferential direction of the fixed drum. Thereby, the scrap cut from the electrode sheet moving along the circumferential direction of the fixed drum can be more reliably sucked into the suction holes.

[0024] In addition, the effects that can be easily predicted by those skilled in the art from the configuration according to the preferred embodiment of the present invention can be included.

[0025] The following drawings attached to this specification illustrate the preferred embodiments of the present invention and serve to further understand the technical idea of the present invention together with the detailed description of the invention to be described later. Therefore, the present invention should not be construed as being limited only to the matters described in such drawings.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

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Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0027] Hereinafter, with reference to the drawings, preferred embodiments of the present invention will be described in detail so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement it. However, the present invention may be realized in various different forms and is not limited or restricted by the following embodiments.

[0028] For the purpose of clearly explaining the present invention, detailed descriptions of parts not related to the explanation or known technologies related that may obscure the gist of the present invention are omitted. When assigning reference numerals to the components of each figure in this specification, the same or similar reference numerals are assigned to the same or similar components throughout the specification.

[0029] Also, the terms and words used in this specification and the claims should not be construed as being limited to their ordinary or dictionary meanings. The inventor should interpret them as meanings and concepts consistent with the technical idea of the present invention in accordance with the principle that the inventor can appropriately define the concept of the terms in order to explain his invention in the best way.

[0030] FIG. 1 is a side view of a laser notching device according to an embodiment of the present invention, and FIG. 2 is a schematic view showing the state in which the electrode sheet shown in FIG. 1 is notched.

[0031] A laser notching device according to an embodiment of the present invention can notch an electrode tab (T) on an electrode sheet 10.

[0032] The laser notching device can include a drum unit 100 that moves the electrode sheet 10 and a laser unit 200 that irradiates the electrode sheet 10 with a laser beam. The drum unit 100 and the laser unit 200 can be located on opposite sides of the electrode sheet 10.

[0033] The laser unit 200 can irradiate a laser beam (L) (see FIG. 3). The laser unit 200 can adjust the position where the laser beam (L) is irradiated, whereby the electrode sheet 10 can be notched into a preset shape. Since the configuration of the laser unit 200 is well-known technology, a detailed description thereof will be omitted.

[0034] Referring to FIG. 2, the electrode sheet 10 can include a patterned portion 11 on which an active material is coated on an electrode current collector and a non-patterned portion 12 where the electrode current collector is exposed because the active material is not coated. Each non-patterned portion 12 can be located on both sides in the width direction of the patterned portion 11. However, it should be possible for the non-patterned portion 12 to be located only on one side in the width direction of the patterned portion 11.

[0035] The laser notching device can notch a part of the edge side in the width direction of the electrode sheet 10. More specifically, the laser unit 200 can irradiate the electrode sheet 10 with a laser beam to notch a part of the edge side in the width direction of the electrode sheet 10. Hereinafter, a part of the edge side in the width direction of the electrode sheet 10 will be named as a notching region and described.

[0036] When the notching regions of the electrode sheet 10 are provided on both sides in the width direction of the electrode sheet 10, the laser unit 200 may be provided with a pair spaced apart in the width direction of the electrode sheet 10, and each notching region can be notched.

[0037] The notching region of the electrode sheet 10 can include the plain portion 12. Therefore, the plain portion 12 provided on one side in the width direction of the electrode sheet 10 may be processed into an electrode tab (T). The plain portion 12 provided on the other side in the width direction of the electrode sheet 10 may be notched and removed by a laser notching device, but is not limited thereto.

[0038] When the notching region of the electrode sheet 10 is notched, scrap 19 cut from the electrode sheet 10 can be formed. The scrap 19 may be formed continuously and extend long. The laser notching device can include a scrap suction portion 140 that sucks such scrap 19. The laser notching device can further include a mask jig 130 that faces the laser unit 200 with the electrode sheet 10 interposed therebetween.

[0039] The mask jig 130 and the scrap suction portion 140 may be provided in the drum unit 100, and more specifically, in the fixed drum 120 (see FIG. 3) described later. With respect to the moving direction of the electrode sheet 10, the scrap suction portion 140 can be located behind the mask jig 130.

[0040] FIG. 3 is a perspective view of a laser notching device according to an embodiment of the present invention, and FIG. 4 is a perspective view of the drum unit shown in FIG. 3.

[0041] The drum unit 100 can include a rotating drum 110 that contacts the electrode sheet 10 and moves the electrode sheet 10, and a fixed drum 120 located on one side in the axial direction of the rotating drum 110.

[0042] The rotating drum 110 can be rotated by a driving device such as a motor (not shown), and the fixed drum 120 may be fixed and may not rotate. That is, the rotating drum 110 can rotate with respect to the fixed drum 120.

[0043] The rotating drum 110 and the fixed drum 120 may be arranged to have the same axis as each other. The axial direction of the rotating drum 110 and the fixed drum 120 may be parallel to the width direction of the electrode sheet 10.

[0044] The radial step between the outer periphery of the rotating drum 110 and the outer periphery of the fixed drum 120 may be very small. Preferably, the outer periphery of the rotating drum 110 and the outer periphery of the fixed drum 120 can be located on the same curved surface. That is, the outer diameter of the fixed drum 120 and the outer diameter of the rotating drum 110 may correspond to each other, where corresponding means being similar or identical to each other.

[0045] A part of the electrode sheet 10 can face the rotating drum 110, and another part can face the fixed drum 120. More specifically, the fixed drum 120 can face the notching region of the electrode sheet 10 in its radial direction. The notching region can include the plain part 12 processed into the electrode tab (T).

[0046] The mask jig 130 may be provided on the fixed drum 120. The mask jig 130 can be directed towards the notching region of the electrode sheet 10. The laser unit 200 can face the mask jig 130 with the notching region of the electrode sheet 10 interposed therebetween. The mask jig 130 may be in close contact with the notching region of the electrode sheet 10. Thus, it is possible to prevent the electrode sheet (S) from flowing unnecessarily during the progress of the notching process.

[0047] A cutting hole 131 may be formed in the mask jig 130. A foreign matter collection hole 132 may be further formed in the mask jig 130.

[0048] The laser unit 200 can face the cutting hole 131 across the notching area of the electrode sheet 10. Therefore, the laser beam (L) irradiated from the laser unit 200 and cutting the notching area can pass through the cutting hole 131. In order to notch the notching area of the moving electrode sheet 10 into a preset shape to form the electrode tab (T), the shape of the cutting hole 131 may be determined by the shape of the electrode tab (T).

[0049] The foreign matter collection hole 132 can be located around the cutting hole 131. Foreign matters such as dust generated while the notching process is in progress can be collected in the foreign matter collection hole 132.

[0050] However, the foreign matter collection hole 132 is not formed in the mask jig 130, and it is also possible for foreign matters such as dust to be collected in the suction hole 141 of the scrap suction part 140 described later.

[0051] The scrap suction part 140 may be provided on the fixed drum 120. More specifically, a mounting groove 121 for mounting the scrap suction part 140 may be formed in the fixed drum 120.

[0052] The mounting groove 121 may be formed by a part of the outer periphery of the fixed drum 120 being recessed or cut out inward. Also, the mounting groove 121 may be open toward the side opposite to the rotating drum 110 with respect to the axial direction of the fixed drum 120.

[0053] The mask jig 130 may be mounted in the mounting groove 121 together with the scrap suction part 140. For example, the scrap suction part 140 may be integrally formed with the mask jig 130 or mounted in the mounting groove 121 in a state of being fastened to each other. However, it is not limited thereto, and of course, it is also possible to form a separate groove for mounting the mask jig 130 in the fixed drum 120.

[0054] The scrap suction part 140 can continuously remove the scrap 19 (see FIG. 2) by sucking the scrap 19 from the notched electrode sheet 10.

[0055] Since the scrap suction part 140 is attached to the fixed drum 120, the suction of the scrap 19 can be made quickly and reliably as compared with the case where the scrap suction part is arranged outside the drum unit 100 separately from the drum unit 100.

[0056] The laser beam (L) is irradiated toward the mask jig 130 to notch the notching area of the electrode sheet 10, and the scrap 19 may be generated in such a process. Therefore, the removal of the scrap 19 must be made after the notching process. For this purpose, the scrap suction part 140 can be located behind the mask jig 130 with respect to the moving direction of the electrode sheet 10.

[0057] The scrap suction part 140 can be located between the mask jig 130 and the lowermost end part of the fixed drum 120 with respect to the circumferential direction of the fixed drum 120. Therefore, the scrap suction part 140 can quickly suck the scrap 19 before the scrap 19 droops downward.

[0058] The scrap suction part 140 may be formed with a suction hole 141 for sucking the scrap 19. A negative pressure can act on the suction hole 141 to suck the scrap 19. The suction hole 141 can suck and remove not only the scrap 19 but also foreign matters such as dust generated in the notching process of the electrode sheet 10.

[0059] The suction hole 141 may be extended along the circumferential direction of the fixed drum 120. Thereby, the scrap 19 cut from the electrode sheet 10 moving along the circumferential direction of the fixed drum 120 can be more reliably sucked into the suction hole 141.

[0060] On the other hand, the laser notching device may further include a discharge unit 150 that is connected to the scrap suction unit 140 and discharges the scrap 19 sucked into the scrap suction unit 140.

[0061] The discharge unit 150 may have a pipe form. The discharge unit 150 may be connected to the scrap suction unit 140 outside the axial direction of the fixed drum 120.

[0062] On the other hand, when notching the edges on both sides in the width direction of the electrode sheet 10, as described above, a pair of laser units 200 may be provided. In this case, a pair of fixed drums 120 may be provided on both axial sides of the rotating drum 110. Each fixed drum 120 may be provided with a mask jig 130 and a scrap suction unit 140, and a discharge unit 150 may be connected to each fixed drum 120.

[0063] FIG. 5 is a cross-sectional view taken along line A-A' of FIG. 4, and FIG. 6 is a cross-sectional view taken along line B-B' of FIG. 4.

[0064] The rotating drum 110 may have a through hole inside. And an extension part 122 may be formed on the fixed drum 120 so as to extend in the axial direction of the fixed drum 120 and be inserted into the inside of the rotating drum 110.

[0065] The rotating drum 110 may surround the extension part 122 and rotate with respect to the extension part 122. The inner circumference of the rotating drum 110 and the outer circumference of the extension part 122 may face each other. For the smooth rotation of the rotating drum 110, a bearing (not shown) may be provided between the inner circumference of the rotating drum 110 and the outer circumference of the extension part 122.

[0066] Thereby, the fixed drum 120 and the rotating drum 110 may be easily connected, and the coaxial relationship between the fixed drum 120 and the rotating drum 110 can be stably maintained.

[0067] The fixed drum 120 and the extension part 122 can have a through hole inside. Although not shown in FIGS. 5 and 6, a rotating shaft that rotates together with the rotating drum 110 may be arranged in the internal through holes of the fixed drum 120 and the extension part 122.

[0068] On the other hand, a predetermined chamber communicating with the suction hole 141 may be formed inside the scrap suction part 140. Thus, the scrap 19 may be sucked into the chamber through the suction hole 141.

[0069] The chamber may be a space defined by the scrap suction part 140 covering the mounting groove 121 of the fixed drum 120. However, it is not limited thereto, and it goes without saying that the internal space surrounded by the scrap suction part 140 can also be defined as the chamber.

[0070] Also, the chamber may communicate with the inside of the mask jig 130. Thus, foreign matters such as dust may be sucked into the chamber through the foreign matter collection hole 132 of the mask jig 130. However, it is not limited thereto, and it goes without saying that a separate chamber can also be formed in the mask jig 130.

[0071] A connection hole 142 to which the discharge part 150 is connected may be formed in the scrap suction part 140. The connection hole 142 communicates with the chamber and may be formed to penetrate toward the outside in the axial direction of the fixed drum 120. Thereby, the scrap 19 sucked into the chamber through the suction hole 141 of the scrap suction part 140 may be discharged to the discharge part 150 through the connection hole 142.

[0072] An inhalation device (not shown) for generating a negative pressure may be connected to the discharge unit 150. Therefore, a negative pressure can act inside the discharge unit 150, and the negative pressure can act up to the chamber and the inhalation hole 141 through the connection hole 142. Thereby, foreign matters such as dust generated in the notching process of the electrode sheet 10 and the scrap 19 may be quickly inhaled into the inhalation hole 141.

[0073] In addition, since the foreign matters and the scrap 19 inhaled into the inhalation hole 141 are discharged to the discharge unit 150, the downtime of the equipment for removing the foreign matters and the scrap 19 can be reduced, and the efficiency of the notching process can be improved.

[0074] FIG. 7 is a perspective view of a laser notching device according to another embodiment of the present invention, and FIG. 8 is a cross-sectional view taken along line C-C' of FIG. 7.

[0075] The laser notching device according to another embodiment of the present invention is the same as the above-described one embodiment except that the scrap 19 is discharged through the passage 123 inside the drum unit 100' instead of the discharge unit 150. Therefore, hereinafter, the content overlapping with the above-described content will be omitted, and the description will focus on the differences.

[0076] A discharge passage 123 for guiding the scrap 19 inhaled by the scrap suction unit 140 may be formed in the extension portion 122 of the fixed drum 120 according to another embodiment of the present invention.

[0077] The discharge passage 123 may be formed between the outer circumference and the inner circumference of the extension portion 122. Since the extension portion 122 is fixed without rotating like the fixed drum 120, the discharge passage 123 does not shake, and the scrap 19 can be stably discharged into the discharge passage 123.

[0078] The discharge passage 123 may communicate with the chamber in the scrap suction unit 140. Therefore, the scrap 19 inhaled into the chamber through the inhalation hole 141 of the scrap suction unit 140 may be discharged into the discharge passage 123.

[0079] The discharge passage 123 may extend to the end of the extension part 122. The end of the extension part 122 may be located inside the rotary drum 110 or may protrude from the rotary drum 110 in the axial direction of the rotary drum 110.

[0080] An inhalation device (not shown) for generating a negative pressure may be connected to the discharge passage 123. Therefore, a negative pressure can act inside the discharge passage 123, and the negative pressure can act up to the chamber and the inhalation hole 141. Thereby, foreign matters such as dust generated in the notching process of the electrode sheet 10 and the scrap 19 can be quickly inhaled into the inhalation hole 141.

[0081] In addition, the foreign matters and the scrap 19 inhaled into the inhalation hole 141 are discharged into the discharge passage 123, so that the idle time of the equipment for removing the foreign matters and the scrap 19 can be reduced and the efficiency of the notching process can be improved.

[0082] In the case of the present embodiment, since it is not necessary to separately connect a discharge part 150 to the fixed drum 120, there is an advantage that the space required for installing the discharge part 150 can be saved.

[0083] The above description merely exemplarily explains the technical idea of the present invention, and those having ordinary knowledge in the technical field to which the present invention pertains can make various modifications and deformations without departing from the essential characteristics of the present invention.

[0084] Therefore, the embodiments disclosed in the present invention are for explanatory purposes rather than for limiting the technical idea of the present invention, and the scope of the technical idea of the present invention is not limited by such embodiments.

[0085] The protection scope of the present invention must be interpreted according to the following claims, and all technical ideas within the equivalent scope must be interpreted as being included in the scope of rights of the present invention.

Explanation of Reference Numerals

[0086] 10 Electrode sheet 11 Ground portion 12 Non-ground portion 19 Scrap T Electrode tab 100 Drum unit 110 Rotating drum 120 Fixed drum 121 Mounting groove 122 Extension part 123 Discharge passage 130 Mask jig 131 Cutting hole 132 Foreign matter collection hole 140 Scrap suction part 141 Suction hole 142 Connection hole 150 Discharge part 200 Laser unit

Claims

1. A laser notching device for notching an electrode tab on an electrode sheet, a laser unit that irradiates a laser beam onto the electrode sheet; a rotating drum that contacts the electrode sheet and moves the electrode sheet; a fixed drum located on one side in the axial direction of the rotating drum; and a laser notching device including a scrap suction portion provided on the fixed drum for sucking scraps cut from the electrode sheet by the laser beam.

2. further including a mask jig provided on the fixed drum and facing the laser unit with the electrode sheet sandwiched therebetween, wherein the scrap suction portion is located behind the mask jig with respect to the moving direction of the electrode sheet, the laser notching device according to claim 1.

3. wherein the scrap suction portion is located between the mask jig and the lowermost end portion of the fixed drum in the circumferential direction of the fixed drum, the laser notching device according to claim 2.

4. The fixed drum and the rotating drum are arranged to be coaxial, the laser notching device according to any one of claims 1 to 3.

5. The outer diameter of the fixed drum and the outer diameter of the rotating drum correspond to each other, the laser notching device according to claim 4.

6. The fixed drum faces a part of the edge side in the width direction of the electrode sheet in its radial direction, the laser notching device according to any one of claims 1 to 3.

7. A mounting groove for mounting the scrap suction portion is formed in the fixed drum, the laser notching device according to any one of claims 1 to 3.

8. The scrap suction part includes a suction hole extending along the circumferential direction of the fixed drum, and the laser notching device according to any one of claims 1 to 3.

9. The laser notching device according to any one of claims 1 to 3, further including a discharge part connected to the scrap suction part and discharging the scrap sucked into the scrap suction part.

10. In the fixed drum, an extension part extending in the axial direction of the fixed drum and inserted into the inside of the rotating drum is formed, and the laser notching device according to any one of claims 1 to 3.

11. The rotating drum surrounds the extension part and rotates with respect to the extension part, and the laser notching device according to claim 10.

12. In the extension part, a discharge passage for guiding the scrap sucked into the scrap suction part is formed, and the laser notching device according to claim 10.

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