Electrode Etching Equipment

Abstract

The present invention includes an electrode assembly support roller; and a laser irradiation device; The electrode assembly support roller includes two or more cylindrical roller segments, which are connected to a roller segment in contact with one fixed shaft while being spaced apart from each other, and the laser irradiation device is positioned so as to irradiate a laser beam into a space formed between the cylindrical roller segments, thereby providing an electrode etching device.

Description

[Technical field]

[0001] The present invention relates to an electrode etching apparatus used for etching electrode active materials, etc. [Background technology]

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0149907 filed on November 3, 2021, and all contents disclosed in the documents of that Korean patent application are incorporated as part of this specification.

[0003] The demand for secondary batteries is growing rapidly due to the increasing demand for mobile devices, electric vehicles, etc. In particular, lithium secondary batteries, which have high energy density and voltage, are becoming more common and are being used widely.

[0004] A lithium secondary battery is composed of an electrode in which an active material is applied to a current collector, i.e., an electrode assembly in which a porous separator is interposed between a positive electrode and a negative electrode, is impregnated with an electrolyte containing a lithium salt. The electrode is manufactured by a mixing process in which an active material, a binder, and a conductive material are mixed / dispersed in a solvent to prepare a slurry, a coating process in which the active material slurry is applied to a current collector in the form of a thin film and dried, and a pressing process to increase the capacity density of the electrode after the coating process and to increase the adhesion between the current collector and the active material, and then form an active material layer on the current collector.

[0005] When the active material slurry is applied to a current collector, as shown in FIG. 1, a sliding portion is formed at the edge of the active material layer where the thickness of the active material layer gradually decreases, resulting in a problem of a decrease in the capacity of the active material layer. In addition, when the slurry is applied to both sides of the current collector, mismatching occurs, in which the positions of the slurries applied to the upper and lower surfaces do not match. Such mismatching causes the positions of the active material layers to shift when the positive and negative electrodes are facing each other, and such shifted portions reduce the efficiency of charging and discharging. In particular, the mismatching portion may cause lithium to be deposited on the surface of the negative electrode, and if this lithium deposition continues for a long time, a decrease in battery capacity occurs.

[0006] Therefore, in order to uniformly form the ends of the active material layer and prevent the formation of sliding parts and / or mismatching parts, a process of etching the sliding parts is performed. Conventional etching of the sliding parts is performed by the method shown in Fig. 2. That is, while an electrode assembly having an electrode active material layer formed on the upper or lower surface or upper and lower surfaces of a current collector sheet is transported by a roll-to-roll process, a laser beam is irradiated from a laser irradiation device attached to the upper or lower surface or upper and lower surfaces of the electrode assembly to etch and remove the sliding parts of the electrode active material layer.

[0007] However, this method causes vertical undulations in the electrode assembly 50 located between the rolls, which causes the etching position to fluctuate and leads to poor focusing of the laser, resulting in frequent etching defects. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2000-251942 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention has been devised to solve the problems of the prior art as described above, The objective of the present invention is to provide an electrode etching apparatus that can improve the accuracy of etching (ablation) by stably fixing an electrode assembly to be etched, and can effectively prevent damage to an etching die caused by a laser beam and the resulting damage to an electrode assembly. [Means for solving the problem]

[0010] In order to achieve the above object, the present invention provides Electrode assembly support rollers; and A laser irradiation device; the electrode assembly support roller includes two or more cylindrical roller segments, the two or more cylindrical roller segments being coupled to a roller segment in contact with one fixed shaft in a spaced apart state; The laser irradiation device includes an electrode etching device positioned to irradiate a laser beam into the space formed between the cylindrical roller segments. In one embodiment of the invention, one or more of the cylindrical roller segments have features that allow them to be moved and fixed along a fixed axis.

[0011] In one embodiment of the present invention, the one or more movable and fixable cylindrical roller segments may be one cylindrical roller segment located at the outermost edge of one end of the support roller among the cylindrical roller segments, two cylindrical roller segments located at the outermost edges of both ends of the support roller, or the entire cylindrical roller segment that constitutes the support roller.

[0012] In an embodiment of the present invention, the one or more movable and fixable cylindrical roller segments may be movable and fixed to match the width of the electrode assembly.

[0013] In one embodiment of the present invention, the fixed shaft may be a rotating shaft.

[0014] In one embodiment of the present invention, one or more of the cylindrical roller segments may be provided with one or more suction holes on a circumferential surface thereof.

[0015] In one embodiment of the present invention, the cylindrical roller segment having one or more suction holes may be one cylindrical roller segment located at the outermost edge of one end of a support roller among the cylindrical roller segments, or two cylindrical roller segments located at the outermost edges of both ends of a support roller, or the entire cylindrical roller segment constituting the support roller.

[0016] In an embodiment of the present invention, the suction hole may be connected to a suction device through an internal space of the cylindrical roller segment.

[0017] In an embodiment of the present invention, the electrode etching apparatus may further include a traveling device for allowing the electrode assembly to travel while forming an interior angle of 70 degrees to 160 degrees around the support roller.

[0018] In an embodiment of the present invention, the traveling facility may include traveling rollers located in front of and behind the support roller with respect to a moving direction of the electrode assembly.

[0019] In an embodiment of the present invention, the laser irradiation device may be disposed above an outer surface of an electrode assembly supported by surface contact of an inner surface with a circumferential surface of the support roller.

[0020] In one embodiment of the present invention, the laser irradiation device may be installed to be movable along an axis parallel to the cylindrical roller segment fixing axis.

[0021] In one embodiment of the present invention, the laser irradiation device may be fixed to a guide rail located on an axis parallel to the cylindrical roller segment fixing axis.

[0022] In an embodiment of the present invention, the electrode assembly may have an inner surface formed of a current collector sheet and an outer surface formed of an electrode active material layer.

[0023] In an embodiment of the present invention, the electrode etching apparatus may be used to etch an electrode active material layer in an electrode assembly including an electrode active material layer stacked on a current collector sheet. Effect of the Invention

[0024] The electrode etching apparatus of the present invention provides an effect of improving the accuracy of etching (ablation) by stably fixing an electrode assembly to be etched, and effectively preventing damage to an etching die caused by a laser beam and the electrode assembly therefrom, thereby providing excellent etching quality. [Brief description of the drawings]

[0025] [Figure 1] FIG. 2 is a cross-sectional view illustrating one embodiment of an electrode assembly. [Diagram 2] 1 is a cross-sectional view showing a schematic diagram of an embodiment of a conventional electrode assembly etching process. [Diagram 3] 11A to 11C are cross-sectional views each showing a schematic diagram of another embodiment of an electrode assembly etching step. [Figure 4] 1 is a cross-sectional view illustrating an embodiment of an electrode etching apparatus of the present invention. [Diagram 5] 1 is a perspective view showing a schematic diagram of an embodiment of an electrode etching apparatus of the present invention; [Figure 6] 1 is a perspective view showing a schematic diagram of an embodiment of an electrode etching apparatus of the present invention; [Figure 7] FIG. 2 is a cross-sectional view showing a schematic state of the electrode etching apparatus of the present invention in use. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in order to enable those skilled in the art to easily carry out the present invention. However, the present invention may be embodied in several different forms and is not limited to the embodiments set forth herein. The same reference numerals are used throughout the specification to refer to similar parts.

[0027] When a component is said to be "connected, provided, or installed" to another component, it should be understood that it can be directly connected or installed to the other component, but there may also be other components in between. On the other hand, when a component is said to be "directly connected, provided, or installed" to another component, it should be understood that there is no other component in between. Meanwhile, other expressions describing the relationship between components, such as "on" and "directly on" or "between" and "immediately between" or "adjacent to" and "directly adjacent to", should be interpreted similarly.

[0028] 4 and 5 are a cross-sectional view and a perspective view showing one embodiment of the electrode etching apparatus of the present invention, FIG. 6 is a perspective view showing one embodiment of the electrode etching apparatus of the present invention, and FIG. 7 is a cross-sectional view showing the electrode etching apparatus of the present invention in use.

[0029] As shown in FIGS. 4 to 7, the electrode etching (ablation) apparatus 100 of the present invention includes an electrode assembly support roller 10; and a laser irradiation device 20; The electrode assembly support roller 10 includes two or more cylindrical roller segments 11, and the two or more cylindrical roller segments 11 are connected to a fixed shaft 15 in a spaced apart state, The laser irradiation device 20 is characterized in that it is positioned so as to be able to irradiate a laser beam into the space formed between the cylindrical roller segments 11 .

[0030] In the electrode etching apparatus 100 of the present invention, the electrode assembly support roller 10 is configured to include two or more cylindrical roller segments 11, and therefore, as shown in Fig. 3(a), it is possible to prevent damage to the electrode assembly support roller 10 and the electrode assembly that may occur when the electrode assembly 50 is damaged, and as a result, damage to the electrode assembly, as shown in Fig. 3(b), it is possible to prevent damage to the electrode assembly support roller 10 and the electrode assembly that may occur when a laser beam passes through the electrode assembly 50, as a result of failure to adjust the output of the laser irradiation device 20.

[0031] In one embodiment of the present invention, one or more of the cylindrical roller segments 11 have a structure that allows them to move and be fixed along a fixed shaft 15. When one or more of the cylindrical roller segments 11 are configured to be movable and fixed as described above, it is possible to provide an advantage that the electrode etching apparatus 100 can be used in response to electrode assemblies 50 having various sizes.

[0032] The movable and fixable cylindrical roller segment 11 may be one cylindrical roller segment 11 located at the outermost part of one end of the support roller 10 among the cylindrical roller segments 11, or it may be two cylindrical roller segments 11 located at the outermost parts of both ends of the support roller 10, or it may be the entire cylindrical roller segment 11 that constitutes the support roller 10.

[0033] In one embodiment of the present invention, the one or more movable and fixable cylindrical roller segments 11 can be moved and fixed according to the width of the electrode assembly 50. That is, since the spacing between the cylindrical roller segments 11 to be irradiated with the laser beam also changes according to the width of the electrode assembly 50, the above configuration makes it possible to adjust the position of the cylindrical roller segments 11 according to such a change.

[0034] In one embodiment of the present invention, the fixed shaft 15 may be a rotating shaft. When the fixed shaft 15 is a rotating shaft as described above, the cylindrical roller segments 11 constituting the support roller 10 can rotate, and the electrode assembly 50 being fed can run while being supported more smoothly.

[0035] In one embodiment of the present invention, the rotating shaft may be rotated passively while in contact with the electrode assembly 50 being fed, or may be rotated by a separately provided driving device.

[0036] In one embodiment of the present invention, one or more of the cylindrical roller segments 11 may be provided with one or more suction holes 12 on the circumferential surface.

[0037] The cylindrical roller segment 11 having one or more suction holes may be one cylindrical roller segment 11 located at the outermost edge of one end of the support roller 10 among the cylindrical roller segments 11, or it may be two cylindrical roller segments 11 located at the outermost edges of both ends of the support roller 10, or it may be the entire cylindrical roller segment 11 that constitutes the support roller 10.

[0038] In the present invention, the electrode assembly 50 may be composed of, for example, a current collector sheet 51 and an electrode active material layer 52 laminated on an upper surface or a lower surface, or on both the upper and lower surfaces, of the current collector sheet, and the electrode etching apparatus 100 of the present invention may perform a function of etching and removing the electrode active material layer 52 by irradiating a laser beam.

[0039] For example, the electrode etching apparatus 100 of the present invention can be preferably used to etch (ablate) and remove the sliding portion formed at the end portion during coating of the electrode active material, and can also be used to remove the electrode active material from the current collector sheet 51 to form a non-coated portion.

[0040] Therefore, the suction holes 12 can perform a function of sucking and removing the electrode active material particles generated during the removal of the electrode active material, and can also perform a function of adsorbing and fixing the lower surface of the electrode assembly 50.

[0041] In one embodiment of the present invention, the suction holes 12 may be connected to a suction device through the inner space of the cylindrical roller segment. At this time, the suction holes 12 and the suction device may be connected to each other through an exhaust pipe. Also, the exhaust pipe may be connected to the suction device by passing through the inner space of the fixed shaft 15, and the inner space of the fixed shaft 15 itself may function as the exhaust pipe.

[0042] The suction holes 12 may be formed on the entire circumferential surface of the cylindrical roller segment 11, but they may be formed in various shapes in consideration of the type of material to be etched, suction efficiency, etc.

[0043] In an embodiment of the present invention, the electrode etching apparatus 100 may further include a traveling device for allowing the electrode assembly 50 to travel while forming an interior angle of 70 degrees to 160 degrees, preferably 80 degrees to 130 degrees, and more preferably 85 degrees to 95 degrees, around the support roller 10, as shown in FIG. 6.

[0044] When the electrode assembly 50 travels while forming the above-mentioned interior angle, the curved surface portion formed on the electrode assembly 50 forms a large contact area with the support roller 10, which is preferable because the electrode assembly 50 can be more stably supported by the support roller 10.

[0045] In an embodiment of the present invention, the traveling facility may include traveling rollers 61 located in front of and behind the support roller 10 based on the moving direction of the electrode assembly.

[0046] The traveling roller 61 may be rotated passively while in contact with the electrode assembly 50 being fed, or may be rotated by a separately provided driving device.

[0047] In one embodiment of the present invention, the laser irradiation device 20 may be located above the outer surface of the electrode assembly 50, the inner surface of which is supported by surface contact with the circumferential surface of the support roller 10. That is, the laser irradiation device 20 may irradiate a laser beam to the electrode assembly 50 in such a position to perform etching.

[0048] In one embodiment of the present invention, the laser irradiation device 20 may be installed to be movable along an axis parallel to the cylindrical roller segment fixing axis 15. That is, in the present invention, the space where the laser beam is irradiated can be formed by the movement of the cylindrical roller segment 11, and it is preferable that the laser irradiation device 20 is movable as described above, since it is easier to set the electrode etching device 100 to match the size of the electrode assembly 50.

[0049] In one embodiment of the present invention, the laser irradiation device 20 may be fixed to a guide rail 21 located on an axis parallel to a fixed axis of the cylindrical roller segment 11, as shown in Figures 4 and 7. For example, the guide rail 21 and the laser irradiation device 20 may have a protrusion on one of them and a guide groove 22 on the other so that the laser irradiation device 20 can move by sliding, and these may be combined with each other to form a sliding part.

[0050] In the present invention, the laser irradiation device 20 may be any known laser irradiation device that can be used for etching (ablation) of a material without any limitation.

[0051] In one embodiment of the present invention, the electrode assembly 50 may have an inner surface formed of a current collector sheet 51 and an outer surface formed of an electrode active material layer 52 .

[0052] In one embodiment of the present invention, the electrode etching apparatus 100 may be used to etch the electrode active material layer 52 in an electrode assembly including the electrode active material layer 52 laminated on a current collector sheet 51.

[0053] In the electrode etching apparatus 100 of the present invention, except for the configurations specified above, various components known in the art may be adopted without limitation, and the structure of each component device included in the electrode etching apparatus 100 may be manufactured in a structure known in the art if it includes the relevant technical features.

[0054] Although the present invention has been described with reference to the preferred embodiment mentioned above, various modifications and variations can be made without departing from the spirit and scope of the invention, and therefore, the appended claims are intended to cover such modifications and variations as long as they fall within the spirit and scope of the invention. [Explanation of symbols]

[0055] 10: Electrode assembly support roller 11: Cylindrical roller segment 12: Suction hole 15: Fixed axis 20: Laser irradiation device 21: Guide rail 22: Guide groove 50: Electrode assembly 51: Current collector sheet 52: Electrode active material layer 61: Traveling roller 100: Electrode etching equipment

Claims

1. Electrode assembly support rollers; and a laser irradiation device; the electrode assembly support roller includes two or more cylindrical roller segments, the two or more cylindrical roller segments being connected to a fixed shaft in a spaced-apart state with an adjacent roller segment; the laser irradiation device is positioned so as to irradiate a laser beam into a space formed between the cylindrical roller segments, one or more of the cylindrical roller segments are movable and fixed along the fixed axis; the one or more movable and fixable cylindrical roller segments are movable and fixed to accommodate a width of the electrode assembly; the laser irradiation device is positioned above an outer surface of the electrode assembly, the inner surface of which is supported by surface contact with the circumferential surface of the electrode assembly support roller; the laser irradiation device is movably mounted along an axis parallel to the fixed axis of the cylindrical roller segment; The electrode assembly has an inner surface formed of a current collector sheet and an outer surface formed of an electrode active material layer, An electrode etching apparatus for etching and removing a sliding portion formed at an end portion of the electrode active material layer formed on the current collector sheet, the sliding portion being a portion where the thickness of the electrode active material layer is gradually reduced.

2. 2. The electrode etching apparatus according to claim 1, wherein the one or more movable and fixable cylindrical roller segments are one cylindrical roller segment located at the outermost portion of one end of the electrode assembly support roller among the cylindrical roller segments, two cylindrical roller segments located at the outermost portions of both ends of the electrode assembly support roller, or an entire cylindrical roller segment constituting the electrode assembly support roller.

3. 2. The electrode etching apparatus of claim 1, wherein said fixed shaft is a rotating shaft.

4. The electrode etching apparatus according to claim 1 , wherein one or more of the cylindrical roller segments are provided with one or more suction holes on a circumferential surface thereof.

5. 5. The electrode etching apparatus of claim 4, wherein the cylindrical roller segment having one or more suction holes is one cylindrical roller segment located at the outermost portion of one end of the electrode assembly support roller among the cylindrical roller segments, two cylindrical roller segments located at the outermost portions of both ends of the electrode assembly support roller, or an entire cylindrical roller segment constituting the electrode assembly support roller.

6. The electrode etching apparatus according to claim 4 , wherein the suction holes are connected to a suction device through an internal space of the cylindrical roller segment.

7. 2. The electrode etching apparatus of claim 1, further comprising a traveling device for allowing the electrode assembly to travel around the electrode assembly support roller while forming an interior angle of 70 degrees to 160 degrees.

8. 8. The electrode etching apparatus according to claim 7, wherein the traveling facility includes traveling rollers located in front of and behind the electrode assembly supporting roller with respect to a moving direction of the electrode assembly.

9. 2. The electrode etching apparatus according to claim 1, wherein said laser irradiation device is fixed to a guide rail positioned on an axis parallel to said fixed axis of said cylindrical roller segment.

10. A method for removing a sliding portion of an electrode assembly, the method comprising: Electrode assembly support rollers; and a laser irradiation device; the electrode assembly support roller includes two or more cylindrical roller segments, the two or more cylindrical roller segments being connected to a fixed shaft in a spaced-apart state with an adjacent roller segment; the laser irradiation device is positioned so as to irradiate a laser beam into a space formed between the cylindrical roller segments, one or more of the cylindrical roller segments are movable and fixed along the fixed axis; the one or more movable and fixable cylindrical roller segments are movable and fixed to accommodate a width of the electrode assembly; the laser irradiation device is positioned above an outer surface of the electrode assembly, the inner surface of which is supported by surface contact with the circumferential surface of the electrode assembly support roller; The laser irradiation device uses an electrode etching device that is movably installed along an axis parallel to the fixed axis of the cylindrical roller segment, The method comprises: an inner surface of the electrode assembly, the inner surface being formed of a current collector sheet and an outer surface being formed of an electrode active material layer, being supported by surface contact with a circumferential surface of the electrode assembly support roller; a sliding portion, in which the thickness of the electrode active material layer is gradually reduced and formed at an end of the electrode active material layer, is positioned in a space formed between the cylindrical roller segments; and the laser beam is directed at the sliding portion to remove the sliding portion from the current collector sheet.

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