Laser processing method

Abstract

To provide a laser processing method for an electrode that can inhibit reduction in a laser condensing property for a laser due to dust, such as fumes, while inhibiting vibration during laser processing.SOLUTION: The present disclosure provides a method for laser-processing a strip electrode. The method disclosed herein includes: carrying the strip-like shaped electrode to a previously set processing area 210 in a longitudinal direction; and irradiating a surface of the electrode with a laser in the processing area 210 in a state where a first air flow 230 flowing on one surface of the electrode and a second air flow 240 flowing on the other surface of the electrode are formed.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a laser processing method. More specifically, it relates to a laser processing method for a strip electrode used in a power storage device.

Background Art

[0002] A power storage device such as a secondary battery may include a strip electrode. Typically, the electrode includes a metal current collector foil and active material layers disposed on both surfaces of the current collector foil. At the end of the current collector foil, a current collector foil exposed portion where the active material layer is not disposed is provided. A current collector member is connected to the current collector foil exposed portion to form a conduction path.

[0003] The current collector foil exposed portion can be processed by laser processing or the like so as to become at least a part of the tab. At this time, due to the reaction force when dust such as fumes generated by laser irradiation of the electrode scatters, the electrode vibrates in the thickness direction. As a result, the focus of the laser beam may deviate from the electrode. On the other hand, for example, Patent Document 1 discloses a laser processing apparatus capable of accurately cutting a strip electrode. The laser processing apparatus includes a guide that holds the periphery of the laser processing position of the strip electrode. The guide sandwiches the strip electrode from its thickness direction. Thereby, it is said that the flutter (vibration) of the strip electrode can be suppressed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, when dust such as fumes generated during laser processing of the electrode scatters in the path of the laser beam, the laser beam can be diffused, resulting in deterioration of the laser beam's focusing property. Further, when a guide or the like is arranged around the laser irradiation portion, dust such as fumes may adhere to the guide or the like, which may cause damage to the electrode.

[0006] Therefore, the present invention has been made in view of the above circumstances, and a main object thereof is to provide a method for laser processing an electrode that can suppress a decrease in the focusing property of the laser due to dust such as fumes while suppressing vibration during laser processing.

Means for Solving the Problems

[0007] According to the present disclosure, a method for laser processing a strip-shaped electrode is provided. The method disclosed herein includes conveying the strip-shaped electrode in the longitudinal direction to a preset processing area, and performing laser irradiation on the surface of the electrode in a state where a first air flow flowing on one surface of the electrode and a second air flow flowing on the other surface of the electrode are formed in the processing area.

[0008] In the above method, since air flows are formed on both surfaces of the strip-shaped electrode in the processing area, the air flows can support the strip-shaped electrode so as to sandwich it in the thickness direction. Therefore, even when dust such as fumes is generated by laser irradiation, vibration of the strip-shaped electrode in the thickness direction at the laser irradiation portion can be suppressed. Further, since dust such as fumes is blown away by the air flows, a decrease in the focusing property of the laser beam can be suppressed.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0010] Hereinafter, the technology disclosed herein will be described in detail. Matters other than those specifically mentioned in this specification and necessary for the implementation of this technology can be understood as design matters of those skilled in the art based on the prior art in the relevant field. The content of the technology disclosed here can be implemented based on the content disclosed in this specification and common general knowledge in the relevant field.

[0011] In addition, each drawing is schematically drawn, and the dimensional relationships (length, width, thickness, etc.) do not reflect the actual dimensional relationships. Also, in the drawings described below, members and parts that perform the same function are given the same reference numerals, and redundant descriptions may be omitted or simplified. Therefore, for example, the reference numerals attached to the electrodes (finished products) described below are the same as those attached to the strip electrodes before laser processing. In this specification, when a numerical range is described as "A to B (where A and B are arbitrary numerical values)", it means "A or more and B or less", and also includes the meanings of "more than A and less than B", "more than A and B or less", and "A or more and less than B".

[0012] In this specification, the "electric energy storage device" refers to a device that can perform charging and discharging. The electric energy storage device may include batteries such as primary batteries and secondary batteries (for example, lithium-ion secondary batteries and nickel-metal hydride batteries), and capacitors (physical batteries) such as electric double layer capacitors.

[0013] FIG. 1 is an exploded view schematically showing the configuration of an electrode body 20 as an example of an electrode body used in a power storage device. The electrode body 20 is a wound electrode body. The electrode body 20 is an example of the use of an electrode manufactured by the laser processing method disclosed herein. As shown in FIG. 1, the electrode body 20 includes a strip-shaped (long sheet-shaped) positive electrode 22, a strip-shaped (long sheet-shaped) negative electrode 24, and two strip-shaped (long sheet-shaped) separators 26. The positive electrode 22, the negative electrode 24, and the two separators 26 are laminated (arranged) so that their longitudinal directions are aligned, and are wound longitudinally around a winding axis WL. Here, the winding axis WL is the width direction of the electrode orthogonal to the longitudinal direction of the electrodes (the positive electrode 22 and the negative electrode 24).

[0014] As shown in FIG. 1, the positive electrode 22 includes a positive electrode current collector foil 22c, a positive electrode active material layer 22a, and a protective layer 22p. The positive electrode active material layer 22a is disposed on one or both sides (here, both sides) of the positive electrode current collector foil 22c, and extends in the longitudinal direction of the positive electrode 22. The protective layer 22p extends in the longitudinal direction of the positive electrode 22 and is disposed adjacent to the positive electrode active material layer 22a. Here, the protective layer 22p is disposed on one side (the left side in FIG. 2) of the positive electrode active material layer 22a. A plurality of positive electrode tabs 22t are provided at one edge (the left side in FIG. 1) of the positive electrode current collector foil 22c in the direction of the winding axis WL (that is, the width direction of the positive electrode 22 orthogonal to the longitudinal side direction). The plurality of positive electrode tabs 22t each project toward one side (the left side in FIG. 2) in the width direction of the positive electrode 22. The positive electrode tabs 22t project outside the separator 26 in the width direction of the electrode. The plurality of positive electrode tabs 22t are provided at intervals (intermittently) in the longitudinal direction of the positive electrode 22. The plurality of positive electrode tabs 22t are laminated at one end (the left side in FIG. 1) in the width direction of the positive electrode 22 to form a positive electrode tab group. The positive electrode tab group is connected to the positive electrode current collector in the power storage device.

[0015] In FIG. 1, the positive electrode tab 22t has a trapezoidal shape in a plan view such that the width becomes narrower toward the protruding direction of the positive electrode tab 22t. However, the shape of the positive electrode tab 22t is not particularly limited, and for example, it may be triangular, rectangular, polygonal, arc-shaped, or the like. Also, the corners of the positive electrode tab 22t may be rounded.

[0016] As the positive electrode current collector foil 22c constituting the positive electrode 22, a metal foil can be used, and for example, an aluminum foil or the like can be mentioned. The positive electrode active material layer 22a contains a positive electrode active material. The positive electrode active material is appropriately changed depending on the type of the power storage device used. When the power storage device is a lithium ion secondary battery, for example, a lithium composite metal oxide having a layered structure, a spinel structure, an olivine structure, etc. (for example, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2, LiNiO2, LiCoO2, LiFeO2, LiMn2O4, LiNi 0.5 Mn 1.5 O4, LiCrMnO4, LiFePO4, etc.) can be used. Further, the positive electrode active material layer 22a may contain a conductive material, a binder, etc. As the conductive material, for example, carbon black such as acetylene black (AB) or other carbon materials (such as graphite) can be preferably used. As the binder, for example, polyvinylidene fluoride (PVdF) or the like can be used.

[0017] The average thickness of the positive electrode active material layer 22a is not particularly limited, but for example, it is 10 μm or more and 300 μm or less, and preferably 20 μm or more and 200 μm or less. In addition, in this specification, the "average thickness" can be measured by a reflection type laser displacement meter or the like (hereinafter the same).

[0018] The protective layer 22p may contain, for example, insulating inorganic particles, a binder, a carbon material, etc. Examples of the insulating inorganic particles include alumina, silica, etc. Examples of the binder include PVdF, etc. Examples of the carbon material include carbon black, graphite, etc.

[0019] The average thickness of the protective layer 22p is not particularly limited, and can be, for example, 3 μm or more, or 5 μm or more. The average thickness of the protective layer 22p is preferably equal to or less than the average thickness of the positive electrode active material layer 22a, and can be, for example, 50 μm or less.

[0020] The positive electrode active material layer 22a can be formed by dispersing a positive electrode active material and a material (such as a conductive material, a binder, etc.) used as needed in a suitable solvent (such as N-methyl-2-pyrrolidone: NMP) to prepare a paste-like (or slurry-like) composition, applying an appropriate amount of the composition to the surface of the positive electrode current collector foil 22c, and drying.

[0021] As shown in FIG. 1, the negative electrode 24 includes a negative electrode current collector foil 24c and a negative electrode active material layer 24a. The negative electrode active material layer 24a is disposed on one or both sides (here, both sides) of the negative electrode current collector foil 24c and extends in the longitudinal direction of the negative electrode 24. A plurality of negative electrode tabs 24t are provided at one edge (the right side in FIG. 1) of the negative electrode current collector foil 24c in the winding axis WL direction (that is, the width direction of the negative electrode 24 orthogonal to the longitudinal side direction). The plurality of negative electrode tabs 24t each protrude toward one side (the right side in FIG. 2) in the width direction of the negative electrode 24. Here, the protruding direction of the negative electrode tabs 24t is opposite to the protruding direction of the positive electrode tabs 22t in the width direction of the electrode. The negative electrode tabs 24t protrude outside the separator 26 in the width direction of the electrode. The plurality of negative electrode tabs 24t are provided at intervals (intermittently) in the longitudinal direction of the negative electrode 24. The plurality of negative electrode tabs 24t are laminated at one end (the right side in FIG. 1) in the width direction of the negative electrode 24 to form a negative electrode tab group. The negative electrode tab group is connected to the negative electrode current collector in the power storage device.

[0022] As the negative electrode current collector foil 24c constituting the negative electrode 24, a metal foil can be used, for example, a copper foil or the like. The negative electrode active material layer 24a contains a negative electrode active material. The negative electrode active material is appropriately changed according to the type of the power storage device used. When the power storage device is a lithium ion secondary battery, for example, carbon materials such as graphite, hard carbon, and soft carbon can be used. Further, the negative electrode active material layer 24a may further contain a binder, a thickener, and the like. As the binder, for example, styrene butadiene rubber (SBR) or the like can be used. As the thickener, for example, carboxymethyl cellulose (CMC) or the like can be used.

[0023] The average thickness of the negative electrode active material layer 24a is not particularly limited, but for example, it is 10 μm or more and 500 μm or less, preferably 20 μm or more and 300 μm or less.

[0024] The negative electrode active material layer 24a can be formed, for example, by dispersing a negative electrode active material and a material (such as a binder) used as necessary in an appropriate solvent (such as ion-exchanged water) to prepare a paste-like (or slurry-like) composition, applying an appropriate amount of the composition to the surface of the negative electrode current collector foil 24c, and drying it.

[0025] The separator 26 is appropriately changed according to the type of the power storage device. When the power storage device is a lithium ion secondary battery, for example, an insulating microporous sheet can be used, for example, a microporous resin sheet made of a resin such as polyethylene (PE) or polypropylene (PP). Such a microporous resin sheet may have a single-layer structure or a multi-layer structure of two or more layers (for example, a three-layer structure in which PP layers are laminated on both sides of a PE layer). Further, the separator 26 may be provided with a heat-resistant layer (HRL). Note that the separator 26 may be a member or a part that functions to insulate the positive electrode 22 and the negative electrode 24, and does not necessarily have to be the strip-shaped separator 26.

[0026] The laser processing method of the belt-shaped electrode disclosed here will be described below. The laser processing method is used, for example, when forming the positive electrode tab 22t or the negative electrode tab 24t. In the following description, the negative electrode 24 will be described as an example of the belt-shaped electrode, but the positive electrode 22 may also be used.

[0027] FIG. 2 is a front view showing a schematic configuration of a laser processing apparatus 200 according to an embodiment. FIG. 3 is a right side view of the laser processing apparatus 200 shown in FIG. 2. The laser processing method disclosed here is realized, for example, by the laser processing apparatus 200 shown in FIG. 2. The laser processing apparatus 200 has a processing area 210 for irradiating a laser on the surface of the belt-shaped electrode. Here, the laser processing apparatus 200 includes a laser supply unit 220, a belt-shaped electrode conveying means, a first air flow supply means, and a second air flow supply means.

[0028] As shown in FIG. 2, in the laser processing apparatus 200, the processing area 210 is preset in accordance with the position of the laser irradiated from the laser supply unit 220. The laser processing apparatus 200 has a conveying means for conveying the belt-shaped electrode in the longitudinal direction of the electrode. The laser processing apparatus 200 according to the present embodiment has a first roll 252 and a second roll 254. The first roll 252 and the second roll 254 are arranged at positions separated from each other so as to sandwich the processing area 210. The negative electrode 24 is conveyed from the first roll 252 toward the second roll 254. The negative electrode 24 has a first surface 24f which is the surface to be laser-irradiated and a second surface 24b which is the back surface of the first surface 24f. The second surface 24b of the negative electrode 24 is in contact with the first roll 252 and the second roll 254. The first roll 252 and / or the second roll 254 may be driven to rotate by themselves to convey the negative electrode 24. Further, the first roll 252 and / or the second roll 254 may not be driven, and for example, there may be a power source for conveying the negative electrode 24 on the downstream side of the second roll 254.

[0029] As shown in FIG. 3, the negative electrode 24 has a negative electrode active material layer 24a and a negative electrode current collector foil exposed portion 24e that extends in the longitudinal direction adjacent to the negative electrode active material layer 24a. The negative electrode current collector foil exposed portion 24e is a portion where the negative electrode current collector foil 24c is exposed without the negative electrode active material layer 24a being disposed. The negative electrode current collector foil exposed portion 24e is provided at at least one of the ends in the width direction of the negative electrode 24. The negative electrode current collector foil exposed portion 24e forms at least a part of the negative electrode tab 24t when the negative electrode tab 24t is formed by laser processing.

[0030] In the processing area 210, a first air flow 230 flowing on the first surface 24f of the negative electrode 24 and a second air flow 240 flowing on the second surface 24b of the negative electrode 24 are formed. By forming the first air flow 230 and the second air flow 240, the negative electrode 24 is held in a state of being sandwiched from the thickness direction of the negative electrode 24. And while in such a state, the first surface 24f of the negative electrode 24 is irradiated with the laser beam L in the processing area 210. The laser beam L is supplied from the laser supply unit 220. Thereby, it is possible to suppress the vibration of the negative electrode 24 in its thickness direction caused by the laser irradiation of the negative electrode 24. Such vibration is presumed to be caused by the reaction force when dust such as fumes generated when the negative electrode 24 is irradiated with the laser beam scatters. Further, since dust such as fumes is blown away by the first air flow 230 and the second air flow 240, it is possible to suppress a decrease in the condensing property of the laser beam L due to dust such as fumes.

[0031] The first air flow 230 preferably passes through a portion (also referred to as a "laser irradiation portion") on the first surface 24f of the negative electrode 24 where the laser beam L is irradiated, and the second air flow 240 preferably passes through the laser irradiation portion on the second surface 24b of the negative electrode 24. In this case, the laser beam L passes through the first air flow 230 and hits the first surface 24f of the negative electrode 24, melts the negative electrode 24, and then passes through the second air flow 240. According to such a configuration, it is possible to preferably suppress the vibration of the negative electrode 24 in the laser irradiation portion. Further, it is possible to preferably suppress a decrease in the condensing property of the laser beam L due to dust such as fumes. Note that in this specification, the laser irradiation portion refers to not only the surface portion of the electrode on the side where the laser light L is irradiated, but also the entire thickness of the electrode at the surface portion where the laser light L hits.

[0032] The flowing directions of the first air flow 230 and the second air flow 240 are not particularly limited as long as they pass near the laser irradiation portion of the negative electrode 24. Preferably, the first air flow 230 and the second air flow 240 flow in the same direction. Thereby, the laser irradiation portion of the negative electrode 24 can be more appropriately sandwiched and held. In the present embodiment, as shown in FIG. 2, the first air flow 230 and the second air flow 240 flow along the conveyance direction of the negative electrode 24 in the processing area 210. Thereby, since dust such as fumes generated in the laser irradiation portion can be blown downstream where the laser cutting is completed, it is possible to suppress the adhesion of dust such as fumes to the surface of the negative electrode 24 before the laser cutting.

[0033] The first air flow 230 and the second air flow 240 preferably flow at the same speed. Thereby, it is possible to appropriately suppress the deflection of the negative electrode 24 in the processing area 210.

[0034] In one aspect of the present technology, the speeds of the first air flow 230 and the second air flow 240 are preferably faster than the conveyance speed of the negative electrode 24. Thereby, the negative electrode 24 in the processing area 210 can be appropriately held, and the removal of dust such as fumes can be more appropriately performed.

[0035] The first air flow 230 is preferably a laminar flow that flows along the first surface 24f of the negative electrode 24. Also, the second air flow 240 is preferably a laminar flow that flows along the second surface 24b of the negative electrode 24. Thereby, in the processing area 210, the negative electrode 24 is held more stably. Note that laminar flow refers to a steady flow that flows regularly in the flow direction. Laminar flow includes, for example, an air flow that flows in a certain direction at a certain speed.

[0036] The gas forming the first air flow 230 and the second air flow 240 is not particularly limited, and may be, for example, air or an inert gas. Examples of the inert gas include nitrogen gas, argon gas, and the like.

[0037] As shown in FIG. 2, the laser processing apparatus 200 according to the present embodiment includes a first air outlet 232 as means for supplying the first air flow 230. The first air outlet 232 is disposed on the first surface 24f side of the negative electrode 24. The air discharged from the first air outlet 232 flows on the first surface 24f of the negative electrode 24 as the first air flow 230.

[0038] As shown in FIG. 2, the laser processing apparatus 200 according to the present embodiment includes a first air inlet 234. The first air inlet 234 sucks the first air flow 230 that has flowed on the first surface 24f of the negative electrode 24 within the processing area 210. The first air inlet 234 is disposed on the first surface 24f side of the negative electrode 24 so as to face the first air outlet 232 with the processing area 210 therebetween. In this way, by sucking the air discharged from the first air outlet 232 by the first air inlet 234, the first air flow 230 is stably formed from the first air outlet 232 toward the first air inlet 234. Further, since dust such as fumes can be carried to the first air inlet 234 by the first air flow 230, the dust such as fumes can be efficiently collected. As shown in FIG. 2, in the present embodiment, in the transport direction of the negative electrode 24, the first air outlet 232 is disposed upstream of the processing area 210, and the first air inlet 234 is disposed downstream of the processing area 210. Thereby, the first air flow 230 along the transport direction of the negative electrode 24 is realized.

[0039] As shown in FIG. 2, the laser processing apparatus 200 according to the present embodiment includes a second air outlet 242 as means for supplying the second air flow 240. The second air outlet 242 is disposed on the second surface 24b side of the negative electrode 24. The air discharged from the second air outlet 242 flows on the second surface 24b of the negative electrode 24 as the second air flow 240.

[0040] As shown in FIG. 2, the laser processing apparatus 200 according to the present embodiment includes a second suction port 244. The second suction port 244 sucks a second air flow 240 that has flowed on the second surface 24b of the negative electrode 24 within the processing area 210. The second suction port 244 is disposed on the second surface 24b side of the negative electrode 24 so as to face the second air outlet 242 across the processing area 210. In this way, by sucking the air discharged from the second air outlet 242 by the second suction port 244, the second air flow 240 is stably formed from the second air outlet 242 toward the second suction port 244. Further, since dust such as fumes can be carried to the second suction port 244 by the second air flow 240, dust such as fumes can be efficiently collected. As shown in FIG. 2, in the present embodiment, the second air outlet 242 is disposed upstream of the processing area 210 and the second suction port 244 is disposed downstream of the processing area 210 in the conveyance direction of the negative electrode 24. Thereby, the second air flow 240 along the conveyance direction of the negative electrode 24 is realized.

[0041] Note that the first air outlet 232 and the second air outlet 242 may each be an independent air outlet, or the first air outlet 232 and the second air outlet 242 may be a continuous single air outlet. Further, the first suction port 234 and the second suction port 244 may each be an independent suction port, or the first suction port 234 and the second suction port 244 may be a continuous single suction port.

[0042] The conveyance direction of the negative electrode 24 in the processing area 210 is not particularly limited, but as shown in FIG. 2, it is preferable that the conveyance direction is the gravitational direction. Thereby, since dust such as fumes generated in the laser irradiation unit easily flows in the gravitational direction, it is possible to suppress a decrease in the condensing property of the laser beam L due to dust such as fumes. When the first air flow 230 and the second air flow 240 flow along the conveyance direction of the negative electrode 24 in the processing area 210, removal of dust such as fumes is more preferably performed, so that a decrease in the condensing property of the laser beam L due to dust such as fumes can be better suppressed.

[0043] The laser supply unit 220 supplies laser light L to the processing area 210. The configuration of the laser supply unit 220 may be the same as that conventionally used for laser cutting. Although not shown, the laser supply unit includes, for example, a laser oscillator, a laser head, etc. The laser oscillator is a device that generates a laser, which is the heat source for welding. The laser head is the part that irradiates the laser generated by the laser oscillator as laser light L. The laser optical path can be composed of, for example, mirrors, optical fibers, etc. Examples of the laser light L include YAG laser, fiber laser, CO2 laser, semiconductor laser, disk laser, etc.

[0044] In the processing area 210, the laser light L is irradiated onto the negative electrode active material layer 24a or the exposed portion 24e of the negative electrode current collector foil, and the irradiated portion is cut. As shown in FIG. 3, on the downstream side of the processing area 210, a negative electrode tab 24t is formed. The exposed portion 24e of the negative electrode current collector foil may be laser cut so that the negative electrode tab 24t is composed of the exposed portion 24e of the negative electrode current collector foil, but preferably, as shown in FIG. 3, the negative electrode tab 24t is processed to have the exposed portion 24e of the negative electrode current collector foil and the negative electrode active material layer 24a. For example, it is preferable to irradiate the laser light L to the end of the negative electrode active material layer 24a, scan the laser light L toward the exposed portion 24e of the negative electrode current collector foil at the timing of forming the negative electrode tab 24t, and scan the laser light L toward the negative electrode active material layer 24a side at an appropriate timing. Note that the scanning direction of the laser light L is appropriately adjusted according to the shape, size, etc. of the negative electrode tab 24t. For example, by configuring the conveyance speed of the negative electrode 24 and the laser supply unit to be interlocked and controlled, the negative electrode tab 24t can be intermittently formed at the end in the width direction of the negative electrode 24.

[0045] According to the laser processing method disclosed herein, since the first air flow 230 and the second air flow 240 can support the negative electrode 24 in the processing area 210 so as to sandwich it, it is not necessary to provide a guide for directly sandwiching and supporting the negative electrode 24 near the processing area 210. If there is a guide, dust such as fumes may adhere to the guide, and the adhered dust may interfere with the electrode being conveyed, which may cause damage to the electrode. Therefore, in the laser processing method disclosed herein, the above risk can be eliminated.

[0046] In addition, when the positive electrode 22 is employed as the strip electrode, it can be understood by reading "negative electrode" as "positive electrode" in the above technical description. However, the position where the laser beam L is irradiated may be the protective layer 22p instead of the positive electrode active material layer 22a, or the positive electrode tab 22t may be configured to have a positive electrode current collector foil exposed portion and the protective layer 22p.

[0047] Further, the strip electrode can be used not only for the wound electrode body but also for the laminated electrode body. When used for the laminated electrode body, a plurality of electrode sheets each having a tab can be obtained by cutting the strip electrode along the width direction, and then the laminated electrode body can be constructed by laminating the negative electrode and the positive electrode via a separator.

[0048] As described above, some embodiments of the present technology have been described, but the above embodiments are merely examples. The present technology can be implemented in various other forms. The technology described in the claims includes various modifications and changes of the above-exemplified embodiments.

[0049] As described above, specific aspects of the technology disclosed herein include those described in the following items. Item 1: A method for laser processing a strip electrode, comprising conveying the strip electrode in the longitudinal direction to a preset processing area, and performing laser irradiation on the surface of the electrode in a state where a first air flow flowing on one surface of the electrode and a second air flow flowing on the other surface of the electrode are formed in the processing area. Item 2: The laser processing method according to Item 1, which inhales the first air current flowing on one surface of the electrode through the first suction port and inhales the second air current flowing on the other surface of the electrode through the second suction port. Item 3: The laser processing method according to Item 1 or 2, wherein the first air current is a laminar flow flowing along the one surface of the electrode, and the second air current is a laminar flow flowing along the other surface of the electrode. Item 4: The laser processing method according to any one of Items 1 to 3, wherein the first air current and the second air current flow along the conveyance direction of the electrode. Item 5: The laser processing method according to any one of Items 1 to 4, wherein the conveyance direction of the electrode in the processing area is the gravity direction.

Explanation of Signs

[0050] 20 Electrode body 22 Positive electrode 24 Negative electrode 26 Separator 200 Laser processing apparatus 210 Processing area 220 Laser supply unit 230 First air current 232 First air outlet 234 First suction port 240 Second air current 242 Second air outlet 244 Second suction port 252 First roll 254 Second roll

Claims

1. A method for laser processing a strip electrode, comprising: conveying the electrode longitudinally to a preset processing area; and performing laser irradiation on the surface of the electrode in a state where a first air flow flowing on one surface of the electrode and a second air flow flowing on the other surface of the electrode are formed in the processing area. including the first air flow is formed by the first suction port disposed on one surface side of the electrode sucking the air discharged from the first air outlet disposed on one surface side of the electrode; the second air flow is formed by the second suction port disposed on the other surface side of the electrode sucking the air discharged from the second air outlet disposed on the other surface side of the electrode; here, the first air outlet and the first suction port are disposed opposite to each other; the second air outlet and the second suction port are disposed opposite to each other. Laser processing method.

2. The laser processing method according to claim 1, wherein the speeds of the first air flow and the second air flow are faster than the conveying speed of the electrode.

3. The laser processing method according to claim 1 or 2, wherein the first air flow is a laminar flow flowing along one surface of the electrode, and the second air flow is a laminar flow flowing along the other surface of the electrode.

4. The laser processing method according to claim 1 or 2, wherein the first air flow and the second air flow flow along the conveying direction of the electrode.

5. The laser processing method according to claim 1 or 2, wherein the conveying direction of the electrode in the processing area is the direction of gravity.

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