Multi-tab laser cleaning method

Abstract

A multi-tab laser cleaning method, comprising: performing, relative to a processing platform, parallelism collection on each galvanometer to be tiled; tiling a plurality of galvanometers into a galvanometer array, and performing parallelism collection on adjacent galvanometers of the galvanometer array; performing distortion correction on a single scanning field generated by each galvanometer; tiling a plurality of single scanning fields corresponding to the plurality of galvanometers into a full scanning field corresponding to the galvanometer array; normalizing a single-scanning-field coordinate system corresponding to each single scanning field into a full-scanning-field coordinate system corresponding to the full scanning field; acquiring offset information, relative to the advancing direction of a material strip, of a material strip edge of the material strip passing through a laser cleaning apparatus, and performing offset compensation on the galvanometer array on the basis of the offset information; and simultaneously performing laser cleaning on a plurality of tabs on an electrode sheet by means of the galvanometer array. By using the method, the laser cleaning effect is improved while a wider cleaning scanning field is guaranteed.

Description

Multi-electrode laser cleaning method Technical Field

[0001] The present invention relates to the field of laser cleaning, in particular to a multi-electrode laser cleaning method. Background Art

[0002] The lithium battery production process involves laser cleaning of the tabs. Laser cleaning of the tabs typically involves cleaning the surface coating of the pole piece to expose the substrate. Then, through die-cutting, the cleaned area is cut out to serve as the battery tabs.

[0003] Among the current methods of laser cleaning of tabs, one is to use a single laser to clean a narrow tab, which has low cleaning efficiency. Another is to use multiple galvanometers to clean multiple tabs in a wider area, but the precision control during the cleaning process is poor.

[0004] Summary of the Invention

[0005] The present invention provides a multi-tab laser cleaning method, which improves the laser cleaning control accuracy when simultaneously performing laser cleaning of multiple tabs on a wider area.

[0006] An embodiment of the present invention provides a multi-tab laser cleaning method, which includes: performing parallelism correction on each galvanometer to be spliced ​​relative to a processing platform, so that each galvanometer meets a first error requirement; splicing a plurality of the galvanometers into a galvanometer array, and performing parallelism correction between adjacent galvanometers in the galvanometer array, so that adjacent galvanometers tend to be located on the same horizontal plane and meet a second error requirement; performing distortion correction on a single frame generated by each galvanometer, so that the single frame corresponding to each galvanometer meets a third error requirement; splicing a plurality of the single frames corresponding to the plurality of the galvanometers into an entire frame corresponding to the galvanometer array, wherein adjacent single frames are parallel to each other and have overlapping edges; normalizing the single frame coordinate system corresponding to each single frame into an entire frame coordinate system corresponding to the entire frame; obtaining offset information of the edge of the material strip passing through the laser cleaning device relative to the direction of material strip travel, and performing offset compensation on the galvanometer array based on the offset information; and simultaneously performing laser cleaning on a plurality of tabs on a pole piece through the galvanometer array.

[0007] According to the aforementioned embodiment of the present invention, the parallelism correction of each galvanometer to be spliced ​​relative to the processing platform so that each of the galvanometers meets the first error requirement includes: obtaining the focal height of the field lens; based on the focal height of the field lens, adjusting the pitch angle of the galvanometer using a length measuring instrument so that the galvanometer tends to be parallel to the table surface of the processing platform of the laser cleaning device.

[0008] According to any of the aforementioned embodiments of the present invention, the first error is required to be within a range of 0.03 mm or less.

[0009] According to any of the aforementioned embodiments of the present invention, the second error is required to be within a range of 0.05 mm or less.

[0010] According to any of the aforementioned embodiments of the present invention, the distortion correction of the single frame generated by each of the galvanometer mirrors so that the single frame corresponding to each of the galvanometer mirrors meets the third error requirement includes: performing multiple high-precision corrections on each of the galvanometer mirrors until the single frame corresponding to the galvanometer mirrors meets the third error requirement.

[0011] According to any of the aforementioned embodiments of the present invention, each high-precision correction includes: using a two-dimensional imager to evenly divide each of the single frames into several equal parts, generating theoretical coordinate positions corresponding to multiple division points; marking each of the division points on the photographic paper by the laser of the galvanometer, and identifying the actual coordinate position corresponding to each division point by the two-dimensional imager; comparing the actual coordinate position and the theoretical coordinate position of each of the division points to obtain a comparison difference, and performing position compensation on the galvanometer based on the comparison difference.

[0012] According to any of the aforementioned embodiments of the present invention, the single frame corresponding to the galvanometer meets the third error requirement, including: the difference between the actual coordinate position and the theoretical coordinate position of each segmentation point is less than 0.03 mm.

[0013] According to any of the aforementioned embodiments of the present invention, the step of splicing the multiple single frames corresponding to the multiple galvanometers into the entire frame corresponding to the galvanometer array includes: starting from the first single frame and the second single frame, taking the previous single frame of each two adjacent single frames as a reference, performing frame translation and frame rotation on the latter single frame, so that the latter single frame is parallel to the previous single frame and has overlapping edges.

[0014] According to any of the aforementioned embodiments of the present invention, normalizing the single-frame coordinate system corresponding to each of the single frames into the entire-frame coordinate system corresponding to the entire frame includes: making the two coordinate axes of the single-frame coordinate system corresponding to each of the single frames coincide with each other.

[0015] According to any of the aforementioned embodiments of the present invention, the laser cleaning device is provided with edge-finding sensors on the front and rear sides of the laser cleaning station, and the obtaining of the offset information of the edge of the material strip passing through the laser cleaning device relative to the direction of travel of the material strip includes: obtaining the front side deviation amount of the material strip edge at the front side of the laser cleaning station and the rear side deviation amount at the rear side of the laser cleaning station respectively through the edge-finding sensors on the front and rear sides of the laser cleaning station; and obtaining the offset information based on the front side deviation amount and the rear side deviation.

[0016] According to the multi-electrode laser cleaning method of an embodiment of the present invention, on the one hand, the parallelism of each galvanometer to be spliced ​​is corrected relative to the processing platform, and then the parallelism between adjacent galvanometers of the galvanometer array is corrected, and then the single frame generated by each galvanometer is corrected for distortion. After the multiple single frames corresponding to the multiple galvanometers are spliced ​​into the entire frame corresponding to the galvanometer array, the adjacent single frames are parallel to each other and have overlapping edges. After that, the offset information of the material strip edge relative to the material strip travel direction of the material strip passing through the laser cleaning device is obtained, and the galvanometer array is offset compensated based on the offset information, so that when the multiple pole tabs on the pole piece are subsequently laser cleaned simultaneously by the galvanometer array, the control accuracy of the galvanometer array is improved while ensuring a larger and wider cleaning frame, thereby improving the laser cleaning effect. On the other hand, after the multiple single frames corresponding to the multiple galvanometers are spliced ​​into the entire frame corresponding to the galvanometer array, the single frame coordinate system corresponding to each single frame is normalized to the entire frame coordinate system corresponding to the entire frame. Therefore, any point on the entire format can be called without the need for adjustment within a single format, making it easy to control multiple laser modules simultaneously through a host computer, which can greatly save signal transmission time and further improve the efficiency of cleaning work. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0018] FIG1 is a schematic flow chart of an embodiment of a multi-electrode laser cleaning method according to the present invention;

[0019] FIG2 is a schematic structural diagram of a multi-electrode laser cleaning method according to an embodiment of the present invention after the horizontality of the galvanometer is corrected;

[0020] FIG3 is a schematic structural diagram of a single frame before splicing according to an embodiment of a multi-element laser cleaning method of the present invention;

[0021] FIG4 is a schematic diagram of the structure of a single frame after splicing according to an embodiment of a multi-element laser cleaning method of the present invention;

[0022] FIG5 is a schematic structural diagram of a strip edge of a strip passing through a laser cleaning device in one embodiment of a multi-tab laser cleaning method of the present invention;

[0023] FIG6 is a schematic structural diagram of obtaining offset information of a strip edge relative to a direction of travel of a strip passing through a laser cleaning device in one embodiment of a multi-tab laser cleaning method of the present invention.

[0024] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0026] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0027] In addition, the descriptions of "first", "second", etc. in the present invention are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0028] 1 is a schematic flow chart of an embodiment of a multi-tab laser cleaning method according to the present invention. In this embodiment, the multi-tab laser cleaning method includes steps S110 to S170.

[0029] In step S110 , the parallelism of each galvanometer to be spliced ​​is calibrated relative to the processing platform so that each galvanometer meets the first error requirement.

[0030] FIG2 is a schematic structural diagram of a method for laser cleaning of multiple tabs according to an embodiment of the present invention after the horizontality of the galvanometer mirror is corrected.

[0031] In some embodiments, the first error requirement is within a range of 0.03 mm or less.

[0032] In some embodiments, the parallelism of each galvanometer to be spliced ​​relative to the processing platform is corrected so that each galvanometer meets the first error requirement, including: obtaining the focal height of the field lens; based on the focal height of the field lens, using a length measuring instrument to adjust the pitch angle of the galvanometer so that the galvanometer tends to be parallel to the table surface of the processing platform of the laser cleaning device.

[0033] Length measuring instruments include, for example, dial indicators and micrometers.

[0034] In step S120 , a plurality of galvanometer mirrors are spliced ​​into a galvanometer mirror array, and parallelism correction is performed between adjacent galvanometer mirrors in the galvanometer mirror array so that adjacent galvanometer mirrors tend to be located on the same horizontal plane and meet the second error requirement.

[0035] In some embodiments, the second error requirement is within a range of 0.05 mm or less, in one example, the second error requirement is 0.03 mm, and in another example, the second error requirement is 0.05 mm.

[0036] Mechanical calibration of the plurality of galvanometer mirrors 120 can be achieved by performing parallelism calibration on each galvanometer mirror to be spliced ​​relative to the processing platform and performing parallelism calibration between adjacent galvanometer mirrors in the galvanometer mirror array.

[0037] As shown in FIG1 , in step S130 , distortion correction is performed on the single frame generated by each galvanometer mirror, so that the single frame corresponding to each galvanometer mirror meets the third error requirement.

[0038] In some embodiments, step S130 of performing distortion correction on the single frame generated by each galvanometer mirror 120 so that the single frame corresponding to each galvanometer mirror 120 meets the third error requirement includes: performing multiple high-precision corrections on each galvanometer mirror 120 until the single frame corresponding to the galvanometer mirror 120 meets the third error requirement.

[0039] In some embodiments, each high-precision calibration includes: using a two-dimensional imager to evenly divide each single frame into several equal parts, generating theoretical coordinate positions corresponding to multiple division points; marking each division point on the photographic paper through the laser of the galvanometer 120, and using the two-dimensional imager to identify the actual coordinate position corresponding to each division point; comparing the actual coordinate position and the theoretical coordinate position of each division point to obtain a comparison difference, and performing position compensation on the galvanometer 120 based on the comparison difference.

[0040] In some embodiments, a single frame corresponding to the galvanometer 120 meets the third error requirement, including: a difference between the actual coordinate position and the theoretical coordinate position of each segmentation point is less than 0.05 mm.

[0041] Typically, each galvanometer mirror 120 needs to undergo three superimposed high-precision calibrations to reduce the error to less than 0.03 mm. If the third error requirement of 0.03 mm is still not met after three calibrations, a fourth high-precision calibration may be performed.

[0042] The purpose of the above-mentioned distortion correction is to eliminate the distortion (such as parallelogram, curved edges, etc.) generated in a single frame, so that the theoretical coordinates in the single frame correspond to the actual coordinates.

[0043] As shown in FIG1 , in step S140 , a plurality of single frames corresponding to a plurality of galvanometer mirrors are spliced ​​into a whole frame corresponding to the galvanometer mirror array, wherein adjacent single frames are parallel to each other and have overlapping edges.

[0044] FIG3 and FIG4 are schematic structural diagrams of a single frame before and after splicing according to an embodiment of a multi-electrode laser cleaning method of the present invention.

[0045] In some embodiments, step S140 of splicing multiple single frames F1 corresponding to multiple galvanometer mirrors 120 into the entire frame corresponding to the galvanometer mirror 120 array includes: starting from the first single frame F1 and the second single frame F1, taking the previous single frame F1 of each two adjacent single frames F1 as a reference, performing frame translation and frame rotation on the subsequent single frame F1, so that the subsequent single frame F1 is parallel to the previous single frame F1 and has overlapping edges.

[0046] In step S150 , the single frame coordinate system corresponding to each single frame F1 is normalized to the entire frame coordinate system corresponding to the entire frame.

[0047] In some embodiments, normalizing the single frame coordinate system corresponding to each single frame F1 to the entire frame coordinate system corresponding to the entire frame includes: making two coordinate axes of the single frame coordinate system corresponding to each single frame F1 coincide with each other.

[0048] At this time, any point on the entire format can be called without the need to adjust within a single format F1, making it easy to control multiple laser modules simultaneously through a host computer, which can greatly save signal transmission time and further improve the efficiency of cleaning work.

[0049] FIG5 is a schematic structural diagram of a material strip edge of a material strip passing through a laser cleaning device in an embodiment of a multi-tab laser cleaning method of the present invention.

[0050] In step S160 , the offset information of the strip edge 910 of the strip 900 passing through the laser cleaning device relative to the strip traveling direction is obtained, and the galvanometer array is compensated for the offset based on the offset information.

[0051] FIG6 is a schematic diagram illustrating a structure for obtaining information about the offset of a strip edge 910 of a strip 900 passing through a laser cleaning apparatus relative to the direction of the strip's travel, in one embodiment of a multi-tab laser cleaning method according to the present invention. In some embodiments, the laser cleaning apparatus is provided with edge-finding sensors 800 at the front and rear sides of the laser cleaning station. The steps of obtaining information about the offset of a strip edge 910 of a strip 900 passing through the laser cleaning apparatus relative to the direction of the strip's travel may include: obtaining, using the edge-finding sensors 800 at the front and rear sides of the laser cleaning station, respectively, the front deviation of the strip edge 910 at the front of the laser cleaning station and the rear deviation of the strip edge 910 at the rear of the laser cleaning station; and obtaining offset information based on the front and rear deviations.

[0052] As shown in FIG1 , in step S170 , a plurality of tabs on a pole piece are laser cleaned simultaneously by a galvanometer array.

[0053] According to the multi-ear laser cleaning method of an embodiment of the present invention, on the one hand, the parallelism of each galvanometer 120 to be spliced ​​is corrected relative to the processing platform 110, and then the parallelism between adjacent galvanometers 120 of the galvanometer array is corrected, and then the single frame F1 generated by each galvanometer 120 is corrected for distortion. After the multiple single frames F1 corresponding to the multiple galvanometers 120 are spliced ​​into the entire frame corresponding to the galvanometer array, the adjacent single frames F1 are parallel to each other and have overlapping edges. After that, the offset information of the material strip edge 910 of the material strip 900 passing through the laser cleaning device relative to the direction of travel of the material strip is obtained, and the galvanometer array is offset compensated based on the offset information, so that when the multiple ear tabs on the pole piece are subsequently laser cleaned simultaneously by the galvanometer array, the control accuracy of the galvanometer array is improved while ensuring a larger and wider cleaning frame, thereby improving the laser cleaning effect. Furthermore, after the individual frames F1 corresponding to the multiple galvanometer mirrors 120 are spliced ​​together to form the entire frame corresponding to the galvanometer array, the frame coordinate system corresponding to each individual frame F1 is normalized to the entire frame coordinate system corresponding to the entire frame. Therefore, any point on the entire frame can be accessed without requiring adjustments within the individual frames F1. This facilitates simultaneous control of multiple laser modules from a single host computer, significantly reducing signal transmission time and further improving cleaning efficiency.

[0054] According to the multi-tab laser cleaning method of an embodiment of the present invention, the array splicing of multiple galvanometers 120 can be realized. In one example, 8 galvanometers 120 are spliced ​​into a galvanometer array. In another example, 16 galvanometers 120 are spliced ​​into a galvanometer array. The number of lasers that complete the splicing is large enough, and the corresponding entire format range is large enough. Ultimately, the cleaning of the tabs at any position can be covered within one format.

[0055] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made by using the contents of the present invention specification and drawings under the concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A multi-electrode laser cleaning method, characterized in that: include: Performing parallelism correction on each galvanometer to be spliced ​​relative to the processing platform, so that each of the galvanometers meets the first error requirement; splicing a plurality of the galvanometers into a galvanometer array, and performing parallelism correction between adjacent galvanometers on the galvanometer array so that adjacent galvanometers tend to be located on the same horizontal plane and meet the second error requirement; Performing distortion correction on the single frame generated by each of the galvanometers so that the single frame corresponding to each of the galvanometers meets a third error requirement; splicing the plurality of single frames corresponding to the plurality of galvanometers into the entire frame corresponding to the galvanometer array, wherein adjacent single frames are parallel to each other and have overlapping edges; Normalizing the single frame coordinate system corresponding to each single frame into the entire frame coordinate system corresponding to the entire frame; Obtaining offset information of a strip edge of a strip passing through the laser cleaning device relative to a direction in which the strip travels, and performing offset compensation on the galvanometer array based on the offset information; The plurality of pole ears on the pole piece are laser cleaned simultaneously by the galvanometer array.

2. The multi-electrode laser cleaning method according to claim 1, characterized in that: The step of correcting the parallelism of each galvanometer to be spliced ​​relative to the processing platform so that each galvanometer meets the first error requirement includes: Get the focal height of the field lens; Based on the focal height of the field lens, a length measuring instrument is used to adjust the pitch angle of the galvanometer mirror so that the galvanometer mirror tends to be parallel to the table surface of the processing platform of the laser cleaning device.

3. The multi-electrode laser cleaning method according to claim 1, characterized in that: The first error is required to be within a range below 0.03 mm.

4. The multi-electrode laser cleaning method according to claim 1, characterized in that: The second error is required to be within a range below 0.05 mm.

5. The multi-electrode laser cleaning method according to claim 1, characterized in that: The step of performing distortion correction on the single frame generated by each of the galvanometers so that the single frame corresponding to each of the galvanometers meets the third error requirement includes: Each of the galvanometers is calibrated multiple times with high precision until the single frame corresponding to the galvanometer meets the third error requirement.

6. The multi-electrode laser cleaning method according to claim 5, characterized in that: Each high-precision calibration includes: Using a two-dimensional imager to evenly divide each single image into a number of equal parts, generating theoretical coordinate positions corresponding to a plurality of segmentation points; Each of the segmentation points is marked on the photographic paper by the laser of the galvanometer, and the actual coordinate position corresponding to each segmentation point is identified by a two-dimensional imager; The actual coordinate position of each segmentation point is compared with the theoretical coordinate position to obtain a comparison difference, and the position compensation of the galvanometer is performed based on the comparison difference.

7. The multi-electrode laser cleaning method according to claim 6, characterized in that: The single frame corresponding to the galvanometer meets the third error requirement, including: the difference between the actual coordinate position and the theoretical coordinate position of each segmentation point is less than 0.03 mm.

8. The multi-electrode laser cleaning method according to claim 1, characterized in that: The step of splicing the plurality of single frames corresponding to the plurality of galvanometers into the entire frame corresponding to the galvanometer array comprises: Starting from the first single frame and the second single frame, taking the previous single frame of each two adjacent single frames as a reference, the next single frame is subjected to frame translation and frame rotation, so that the next single frame is parallel to the previous single frame and has overlapping edges.

9. The multi-electrode laser cleaning method according to claim 1, characterized in that: The step of normalizing the single frame coordinate system corresponding to each single frame into the entire frame coordinate system corresponding to the entire frame comprises: The two coordinate axes of the single frame coordinate system corresponding to each of the single frames are made to coincide with each other.

10. The multi-electrode laser cleaning method according to claim 1, characterized in that: The laser cleaning device is provided with edge finding sensors at the front and rear sides of the laser cleaning station, and the step of obtaining the offset information of the edge of the material strip passing through the laser cleaning device relative to the moving direction of the material strip includes: The front deviation of the edge of the material strip at the front side of the laser cleaning station and the rear deviation of the edge of the material strip at the rear side of the laser cleaning station are respectively obtained by edge-finding sensors at the front side and the rear side of the laser cleaning station; The offset information is acquired based on the front deviation amount and the rear deviation amount.

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