Tab defective die cutting method and battery tab

Abstract

The application provides a tab defect die-cutting method and a battery tab. The method comprises the following steps: obtaining a tab defect span of a tab belt; performing cross-tab difference processing on the tab defect span and a preset span to obtain a tab defect difference; and sending a cutting defect identification enable / disable signal to a tab defect identification system according to the tab defect difference, so as to die-cut the tab defect on the tab belt. Through the collection of the tab defect span, the span condition of any tab with a defect on the tab belt is obtained, cross-tab difference processing is performed on the tab defect span and the preset span, the specific position difference of the tab with a defect is determined, the damage degree of the tab with a defect is determined according to the position difference of the defect, the tab with a defect is marked, and the marking precision of the defect identification position is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a method for die-cutting defective battery tabs and battery tabs. Background Technology

[0002] After coating, slitting, and welding of tabs, the positive and negative electrode sheets of lithium batteries enter the winding process, where they are wound together with a separator on a winding machine to form a battery cell. Currently, the electrode sheets are generally supplied to the winding machine in the form of rolls, and it is inevitable that some defective electrode sheets will be produced during the battery cell manufacturing process.

[0003] However, the current cutting process in the lithium battery industry uses die-cutting to mark defective products, and winding to identify and reject defective products. For example, the Chinese patent application with application number CN201510306325.7 is prone to problems such as low accuracy of the position of the defective mark in the die-cutting process, low success rate, and inaccurate winding identification, resulting in huge losses caused by defective products. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for die-cutting defective battery tabs and battery tabs that effectively improves the marking accuracy of defective marking positions.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A method for die-cutting defective products with tabs, the method comprising:

[0007] Obtain the electrode stripe spacing of defective products;

[0008] The defective electrode span is compared with the preset span by the cross-electrode standard deviation to obtain the defective span difference.

[0009] Based on the aforementioned defective span difference, a defective marking enable / disable signal is sent to the electrode defective marking system to perform die-cutting on the defective electrode sheet on the electrode tab.

[0010] In one embodiment, obtaining the electrode defect span of the tab band includes: obtaining the electrode defect end spacing of the tab band, wherein the electrode defect end spacing is the span between the defect point of the current electrode and its end in the tab band.

[0011] In one embodiment, the step of performing cross-polarity standardization processing on the defective electrode span and the preset span to obtain the defective span difference includes: calculating the span difference between the defective electrode end spacing and the preset span to obtain a first span difference.

[0012] In one embodiment, the step of sending a defective electrode marking enable / disable signal to the electrode defect marking system based on the defective span difference to die-cut the defective electrode sheet on the electrode strip includes: detecting whether the first span difference matches a first preset difference; when the first span difference matches the first preset difference, sending a cutting end signal to the electrode defect marking system to die-cut the current electrode end of the electrode strip.

[0013] In one embodiment, the step of detecting whether the first span difference matches the first preset difference further includes: when the first span difference does not match the first preset difference, sending a defective marking start signal to the tab defect marking system to mark the defective part of the tab tape.

[0014] In one embodiment, when the first span difference does not match the first preset difference, a defective marking start signal is sent to the electrode defect marking system to mark the defective part of the electrode strip. Then, the method further includes: performing end point reset die-cutting on the electrode end of the electrode strip.

[0015] In one embodiment, obtaining the electrode defect span of the tab band includes: obtaining the electrode defect start distance of the tab band, wherein the electrode defect start distance is the span between the defect point of the current electrode and its beginning end of the tab band.

[0016] In one embodiment, the step of performing cross-polarity standardization processing on the electrode defect span and the preset span to obtain the defect span difference includes: calculating the span difference between the electrode defect initial spacing and the preset span to obtain a second span difference.

[0017] In one embodiment, the step of sending a defective marking enable / disable signal to the electrode defect marking system based on the defective span difference to die-cut the defective electrode sheet on the electrode strip includes: detecting whether the second span difference matches a second preset difference; when the second span difference matches the second preset difference, sending a cutting end signal to the electrode defect marking system to die-cut the electrode sheet end of the electrode strip.

[0018] A battery tab, comprising a tab die-cutting method as described in any of the above embodiments.

[0019] Compared with the prior art, the present invention has at least the following advantages:

[0020] By collecting the span of defective electrodes, it is easy to obtain the span of any electrode with a defect in the tab band. The span is then compared with the preset span using cross-polarity standardization to determine the specific positional difference of the defective electrode. Finally, the degree of damage to the electrode by the defective electrode is determined based on the positional difference, which facilitates the marking of the defective electrode and effectively improves the marking accuracy of the defective marking position. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a flowchart of a method for die-cutting electrode discs in one embodiment. Detailed Implementation

[0023] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] This invention relates to a method for die-cutting defective electrode sheets. In one embodiment, the method includes acquiring the defective electrode sheet span of the electrode sheet band; performing cross-polarity standardization processing on the defective electrode sheet span and a preset span to obtain a defective electrode sheet difference; and sending a defective electrode sheet marking enable / disable signal to the electrode sheet defect marking system based on the defective electrode sheet difference to die-cut the defective electrode sheets on the electrode sheet band. By acquiring the defective electrode sheet span, it is convenient to obtain the span of any electrode sheet with defects on the electrode sheet band, perform cross-polarity standardization processing on it and a preset span to determine the specific positional difference of the defective electrode sheet within it, and finally determine the degree of damage to the electrode sheet by the defective electrode sheet based on the positional difference of the defective electrode sheet, which facilitates the marking of the defective electrode sheet and effectively improves the marking accuracy of the defective electrode sheet position.

[0027] Please see Figure 1 This is a flowchart of a method for die-cutting defective tabs according to an embodiment of the present invention. The method for die-cutting defective tabs includes some or all of the following steps.

[0028] S100: Obtain the electrode strip defect span of the electrode strap.

[0029] In this embodiment, the defective electrode span is the distance between the defective points on the tab band, that is, the distance between the electrode with the defective point on the tab band and its end, or the lateral spacing between the defective point on the current electrode and its end. Sampling the defective electrode span facilitates determining the position of the electrode with the defective point on the tab band, thereby facilitating the determination of the distance between the defective point on the current defective electrode and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode, thus enabling precise positioning of the defective point on the electrode. In another embodiment, a CCD or CMOS camera is used to detect the surface damage of each electrode on the tab band to determine the position of the defective point on the electrode.

[0030] S200: Perform cross-polarity standardization on the defective electrode span and the preset span to obtain the defective span difference.

[0031] In this embodiment, the defective electrode span is the distance between the defective points on the tab band, that is, the distance between the electrode with the defective point on the tab band and its end, or the lateral spacing between the defective point on the current electrode and its end. Sampling the defective electrode span facilitates determining the position of the electrode with the defective point on the tab band, thereby facilitating the determination of the distance between the defective point on the current defective electrode and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode, thus enabling precise positioning of the defective point on the electrode. In another embodiment, a CCD or CMOS camera is used to detect the surface damage of each electrode on the tab band to determine the position of the defective point on the electrode. The preset span is the standard distance for defective pixels on the tab band, that is, the preset span is the specified distance between the electrode with defective pixels and its end on the tab band, or the standard horizontal span between a defective pixel on any electrode and its end. Specifically, the preset span is the distance between the CCD or CMOS camera and the laser die-cutting machine. By comparing the defective span of the electrode with the preset span, it is easy to determine the difference between the span of the defective pixel on the current electrode and the standard span, thereby facilitating the determination of the difference between the location of the defective pixel on the defective electrode and its allowable location.

[0032] S300: Send a cutting defect identification enable / disable signal to the electrode tab defect identification system according to the defect span difference, so as to die-cut the defective electrode sheet on the electrode tab.

[0033] In this embodiment, the defective span is obtained based on the defective span of the electrode and the preset span. The defective span is the distance between the defective points on the tab band, that is, the distance between the electrode with a defect and its end on the tab band, or the transverse span between the defective point on the current electrode and its end. By sampling the defective span, the position of the electrode with a defect on the tab band is easily determined, thereby facilitating the determination of the distance between the defective point on the current defective electrode and its end on the tab band, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode, thus enabling precise positioning of the defective point on the electrode. In another embodiment, the surface damage of each electrode on the tab band is detected by a CCD or CMOS camera to determine the position of the defective point on the electrode. The preset span is the standard distance for defective pixels on the tab band, that is, the preset span is the specified distance between the electrode with defective pixels and its end on the tab band, or the standard horizontal span between a defective pixel on any electrode and its end. Specifically, the preset span is the distance between the CCD or CMOS camera and the laser die-cutting machine. By comparing the defective span of the electrode with the preset span, it is easy to determine the difference between the span of the defective pixel on the current electrode and the standard span, thereby facilitating the determination of the difference between the location of the defective pixel on the defective electrode and its allowable location. Thus, after determining the defective span difference, according to the positional offset of the defective pixel on the tab band, the current electrode of the tab band is die-cut accordingly. For example, die-cutting is initiated promptly when the defective pixel is at the position requiring cutting, and no die-cutting is performed when the defective pixel is not at the position requiring cutting.

[0034] In the above embodiments, by collecting the span of defective electrode sheets, it is convenient to obtain the span of any electrode sheet with defective points on the tab band. The span is then compared with the preset span for cross-electrode standardization to determine the specific positional difference of the electrode sheet with defective points. Finally, the degree of damage to the electrode sheet by the defective point is determined based on the positional difference of the defective point, which facilitates the marking of the defective electrode sheet and effectively improves the marking accuracy of the defective marking position.

[0035] In one embodiment, obtaining the defective electrode span of the tab band includes: obtaining the defective electrode end spacing of the tab band, where the defective electrode end spacing is the span between the defective point of the current electrode and its end on the tab band. In this embodiment, the defective electrode span is the distance between the defective points on the tab band, that is, the defective electrode span is the distance between the electrode with the defective point and its end on the tab band, or the transverse span between the defective point on the current electrode and its end. By sampling the defective electrode span, it is easy to determine the position of the electrode with the defective point on the tab band, thereby facilitating the determination of the distance between the defective point on the current defective electrode and its end on the tab band, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode, so that the position of the defective point on the electrode is accurately located. In another embodiment, the surface damage of each electrode on the tab band is detected by a CCD or CMOS camera to facilitate the determination of the position of the defective point on the electrode. The electrode defect span is the electrode defect end spacing, which is the span between the defective point of the current electrode and its end on the electrode tab. The electrode defect end spacing is used to calculate the distance between the defective point on the defective electrode and the end of the electrode it is located on, so as to determine the length of the defective point on the defective electrode from the end of the electrode, thereby making it easier to determine whether the defective point on the defective electrode is in a critical position of the electrode, and further making it easier to determine whether the defective point on the defective electrode has damaged the entire electrode.

[0036] Further, the step of performing cross-polarity standardization processing on the defective electrode span and the preset span to obtain the defective span difference includes: calculating the span difference between the defective electrode end distance and the preset span to obtain a first span difference. In this embodiment, the defective electrode span is the distance between the defective points on the tab band, that is, the defective electrode span is the distance between the electrode with defective points on the tab band and its end, and also the transverse span distance between the defective point on the current electrode and its end. By sampling the defective electrode span, it is easy to determine the position of the electrode with defective points on the tab band, thereby facilitating the determination of the distance between the defective point on the current defective electrode of the tab band and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode, so that the position of the defective point on the electrode is accurately located. In another embodiment, the surface damage of each electrode on the tab band is detected by a CCD or CMOS camera to facilitate the determination of the position of the defective point on the electrode. The preset span is the standard distance between the defective points on the tab band, that is, the preset span is the specified distance between the electrode with the defective point and its end on the tab band, or the standard transverse span between the defective point and its end on any electrode. By comparing the defective span of the electrode with the preset span, it is easy to determine the difference between the span of the defective point on the current electrode and the standard span, thereby facilitating the determination of the difference between the location of the defective point on the defective electrode and its allowable location. The electrode end gap is the span between the defective point of the current electrode and its end on the tab band. The electrode end gap is used to calculate the distance between the defective point on the defective electrode and the end of the electrode, facilitating the determination of the length of the defective point from the end of the electrode, thereby facilitating the determination of whether the defective point on the defective electrode is in a critical position on the electrode, and further facilitating the determination of whether the defective point on the defective electrode has damaged the entire electrode. The preset span is the standard span between the defective point of the electrode tab and its end, i.e., the preset span is the safe span between the defective point of the electrode tab and its end. For example, the preset span is the distance between a CCD or CMOS camera and a laser die cutter. The first span difference, as the difference between the defective point distance and the preset span, facilitates the determination of the difference between the distance between the defective point and its end and the safe span, thereby facilitating the determination of the degree of difference between the defective point location and the safe area location of the electrode tab.

[0037] Furthermore, the step of sending a defective marking enable / disable signal to the electrode defect identification system based on the defective span difference to die-cut the defective electrode sheet on the electrode strip includes: detecting whether the first span difference matches a first preset difference; when the first span difference matches the first preset difference, sending a cutting end signal to the electrode defect identification system to die-cut the current electrode end of the electrode strip. In this embodiment, the first span difference is the difference between the electrode end gap and the preset span, that is, the first span difference is the difference between the electrode end gap and the preset span, and the electrode defective span is the distance of the defective point on the electrode strip, that is, the electrode defective span is the distance between the electrode sheet with the defect and the end on the electrode strip, that is, the electrode defective span is the transverse span distance between the defective point on the current electrode and its end. By sampling the defective span of the electrode sheet, the position of the electrode sheet with defective points on the tab band can be easily determined, thereby facilitating the determination of the distance between the defective point on the current defective electrode sheet and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode sheet, thus enabling precise positioning of the defective point on the electrode sheet. In another embodiment, the surface damage of each electrode sheet on the tab band is detected by a CCD or CMOS camera to determine the position of the defective point on the electrode sheet. The preset span is the standard distance of the defective point on the tab band, that is, the preset span is the specified distance between the electrode sheet with defective points on the tab band and its end, or the standard transverse span distance between the defective point on any electrode sheet and its end. By comparing the defective span of the electrode sheet with the preset span, the difference between the span of the current defective point on the electrode sheet and the standard span can be easily determined, thereby facilitating the determination of the difference between the location of the defective point on the defective electrode sheet and its allowable location. The electrode defect spacing is the distance between the defective point of the current electrode and its end on the electrode tab. The electrode defect spacing is used to calculate the distance between the defective point on the defective electrode and the end of the electrode it is located on, so as to determine the length of the distance between the defective point on the defective electrode and the end of the electrode. This makes it easier to determine whether the defective point on the defective electrode is in a critical position on the electrode, and further easier to determine whether the defective point on the defective electrode has damaged the entire electrode. The first preset difference is the standard span difference, that is, the first preset difference is the standard distance between the defective point on the defective electrode and its end. The first span difference matches the first preset difference, indicating that the span difference between the defective point on the defective electrode and its end is within the safe range. This indicates that the defective point on the defective electrode is in a non-critical area of ​​the electrode, and that the defective point on the defective electrode is close to the end cutting position of the electrode. In order to reduce the number of die-cutting times, the cutting mark position that should be after the defective point is directly overlapped with the die-cutting in the winding process. This not only marks the defective electrode, but also improves the die-cutting efficiency of the electrode ear tape.

[0038] Furthermore, the step of detecting whether the first span difference matches the first preset difference further includes: when the first span difference does not match the first preset difference, sending a defective marking activation signal to the electrode defect marking system to mark and die-cut the defective part of the electrode strip. In this embodiment, the first span difference is the difference between the electrode defect end spacing and the preset span, that is, the first span difference is the difference between the electrode defect end spacing and the preset span, and the electrode defect span is the distance of the defective part of the electrode strip, that is, the electrode defect span is the distance between the electrode strip with the defective part and the end of the electrode strip, that is, the electrode defect span is the horizontal span distance between the defective part on the current electrode strip and its end. By sampling the defective span of the electrode sheet, the position of the electrode sheet with defective points on the tab band can be easily determined, thereby facilitating the determination of the distance between the defective point on the current defective electrode sheet and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode sheet, thus enabling precise positioning of the defective point on the electrode sheet. In another embodiment, the surface damage of each electrode sheet on the tab band is detected by a CCD or CMOS camera to determine the position of the defective point on the electrode sheet. The preset span is the standard distance of the defective point on the tab band, that is, the preset span is the specified distance between the electrode sheet with defective points on the tab band and its end, or the standard transverse span distance between the defective point on any electrode sheet and its end. By comparing the defective span of the electrode sheet with the preset span, the difference between the span of the current defective point on the electrode sheet and the standard span can be easily determined, thereby facilitating the determination of the difference between the location of the defective point on the defective electrode sheet and its allowable location. The electrode defect spacing is the distance between the defective point of the current electrode and its end on the electrode tab. The electrode defect spacing is used to calculate the distance between the defective point on the defective electrode and the end of the electrode it is located on, so as to determine the length of the distance between the defective point on the defective electrode and the end of the electrode. This makes it easier to determine whether the defective point on the defective electrode is in a critical position on the electrode, and further easier to determine whether the defective point on the defective electrode has damaged the entire electrode. The first preset difference is the standard span difference, that is, the first preset difference is the standard distance between the defective point on the defective electrode and its end. The first span difference does not match the first preset difference, indicating that the span difference between the defective point on the defective electrode and its end is outside the safe difference range, that is, it indicates that the defective point on the defective electrode is in the critical area of ​​the electrode, that is, it indicates that the defective point on the defective electrode is far from the end cutting position of the electrode. A defective marking start signal is sent to the electrode tab defect marking system to mark the defective point after the electrode tab, which facilitates marking the defective position of the electrode on the defective point, and also facilitates the cutting off of the qualified part after the defective point, effectively saving materials.

[0039] Furthermore, when the first span difference does not match the first preset difference, a defective marking start signal is sent to the electrode defect marking system to mark and die-cut the defective part of the electrode strip. This further includes: performing end-point reset die-cutting on the electrode sheet end of the electrode strip. In this embodiment, the first span difference is the difference between the electrode sheet defect end spacing and the preset span, i.e., the first span difference is the difference between the electrode sheet defect end spacing and the preset span. The electrode defect span is the distance between the defective part of the electrode strip, i.e., the electrode defect span is the distance between the electrode sheet with the defect and its end on the electrode strip, or the transverse span between the defective part on the current electrode and its end. By sampling the defective span of the electrode sheet, the position of the electrode sheet with defective points on the tab band can be easily determined, thereby facilitating the determination of the distance between the defective point on the current defective electrode sheet and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode sheet, thus enabling precise positioning of the defective point on the electrode sheet. In another embodiment, the surface damage of each electrode sheet on the tab band is detected by a CCD or CMOS camera to determine the position of the defective point on the electrode sheet. The preset span is the standard distance of the defective point on the tab band, that is, the preset span is the specified distance between the electrode sheet with defective points on the tab band and its end, or the standard transverse span distance between the defective point on any electrode sheet and its end. By comparing the defective span of the electrode sheet with the preset span, the difference between the span of the current defective point on the electrode sheet and the standard span can be easily determined, thereby facilitating the determination of the difference between the location of the defective point on the defective electrode sheet and its allowable location. The electrode defect spacing is the distance between the defective point of the current electrode and its end on the electrode tab. The electrode defect spacing is used to calculate the distance between the defective point on the defective electrode and the end of the electrode it is located on, so as to determine the length of the distance between the defective point on the defective electrode and the end of the electrode. This makes it easier to determine whether the defective point on the defective electrode is in a critical position on the electrode, and further easier to determine whether the defective point on the defective electrode has damaged the entire electrode. The first preset difference is a standard span difference, that is, the first preset difference is the standard distance between the defective point on the defective electrode and its end. The first span difference does not match the first preset difference, indicating that the span difference between the defective point on the defective electrode and its end is outside the safe difference range, that is, it indicates that the defective point on the defective electrode is in the critical area of ​​the electrode, that is, it indicates that the defective point on the defective electrode is far from the end cutting position of the electrode. A defective marking start signal is sent to the electrode tab defect marking system to perform marking die-cutting on the defective point of the electrode tab, so as to mark the defective position of the electrode on the defective point.In this way, after marking the defective electrode, the electrode is then die-cut at the end, which makes it easier to remove the entire defective electrode during normal die-cutting. It also allows the beginning of the next electrode to be reset, making it easier to die-cut subsequent electrodes.

[0040] In one embodiment, obtaining the defective electrode span of the tab band includes: obtaining the initial defect spacing of the tab band, where the initial defect spacing is the span between the defective point of the current electrode and its beginning end. In this embodiment, the defective electrode span is the distance between the defective points on the tab band, i.e., the distance between the defective electrode span and the end of the tab band, or the transverse span between the defective point on the current electrode and its end. By sampling the defective electrode span, it is easy to determine the position of the electrode with the defective point on the tab band, thereby facilitating the determination of the distance between the defective point on the current defective electrode and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode, thus enabling precise positioning of the defective point on the electrode. In another embodiment, the surface damage of each electrode on the tab band is detected using a CCD or CMOS camera to determine the position of the defective point on the electrode. The electrode defect span is the electrode defect initiation spacing, which is the span between the defective point of the current electrode and its beginning end on the electrode tab. The electrode defect initiation spacing is used to calculate the distance between the defective point on the defective electrode and the beginning end of the electrode, so as to determine the length of the defective point on the defective electrode from the beginning end of the electrode, thereby making it easier to determine whether the defective point on the defective electrode is in a critical position of the electrode, and further making it easier to determine whether the defective point on the defective electrode has damaged the entire electrode.

[0041] Further, the step of performing cross-polarity standardization processing on the defective electrode span and the preset span to obtain the defective span difference includes: calculating the span difference between the initial defective electrode spacing and the preset span to obtain a second span difference. In this embodiment, the defective electrode span is the distance between the defective points on the tab band, that is, the defective electrode span is the distance between the electrode with defective points on the tab band and its end, or the transverse span between the defective point on the current electrode and its end. By sampling the defective electrode span, it is easy to determine the position of the electrode with defective points on the tab band, thereby facilitating the determination of the distance between the defective point on the current defective electrode of the tab band and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode, so that the position of the defective point on the electrode is accurately located. In another embodiment, the surface damage of each electrode on the tab band is detected by a CCD or CMOS camera to facilitate the determination of the position of the defective point on the electrode. The preset span is the standard distance between the defective points on the tab band, that is, the preset span is the specified distance between the electrode with the defective point and its end on the tab band, or the standard transverse span between the defective point and its end on any electrode. By comparing the defective span of the electrode with the preset span, it is easy to determine the difference between the span of the defective point on the current electrode and the standard span, thereby facilitating the determination of the difference between the location of the defective point on the defective electrode and its allowable location. The electrode defect starting distance is the span between the defective point of the current electrode and its beginning end on the tab band. The electrode defect starting distance is used to calculate the distance between the defective point on the defective electrode and the beginning end of the electrode, facilitating the determination of the length of the defective point from the beginning end of the electrode, thereby facilitating the determination of whether the defective point on the defective electrode is in a critical position on the electrode, and further facilitating the determination of whether the defective point on the defective electrode has damaged the entire electrode. The preset span is the standard span between the defective point of the electrode sheet and its beginning point on the tab, i.e., the preset span is the safe span between the defective point of the electrode sheet and its beginning point on the tab. For example, the preset span is the distance between a CCD or CMOS camera and a laser die-cutting machine. The second span difference is the difference between the defective point spacing and the preset span, which facilitates determining the difference between the distance between the defective point and its beginning point on the tab and the safe span, thereby facilitating the determination of the degree of difference between the defective point position and the safe area position on the tab. In another embodiment, the safe area can also be the middle part of the electrode sheet.

[0042] Furthermore, the step of sending a defective marking enable / disable signal to the electrode defect identification system based on the defective span difference to die-cut the defective electrode sheet on the electrode tab strip includes: detecting whether the second span difference matches a second preset difference; when the second span difference matches the second preset difference, sending a cutting end signal to the electrode defect identification system to die-cut the electrode sheet end of the electrode tab strip. In this embodiment, the first span difference is the difference between the electrode sheet defect end spacing and the preset span, that is, the first span difference is the difference between the electrode sheet defect end spacing and the preset span, and the electrode sheet defective span is the distance of the defective point on the electrode tab strip, that is, the electrode sheet defective span is the distance between the electrode sheet with the defect and the end on the electrode tab strip, that is, the electrode sheet defective span is the transverse span distance between the defective point on the current electrode and its end. By sampling the defective span of the electrode sheet, the position of the electrode sheet with defective points on the tab band can be easily determined, thereby facilitating the determination of the distance between the defective point on the current defective electrode sheet and its end, and further facilitating the determination of the specific position of any defective point on the tab band relative to its corresponding electrode sheet, thus enabling precise positioning of the defective point on the electrode sheet. In another embodiment, the surface damage of each electrode sheet on the tab band is detected by a CCD or CMOS camera to determine the position of the defective point on the electrode sheet. The preset span is the standard distance of the defective point on the tab band, that is, the preset span is the specified distance between the electrode sheet with defective points on the tab band and its end, or the standard transverse span distance between the defective point on any electrode sheet and its end. By comparing the defective span of the electrode sheet with the preset span, the difference between the span of the current defective point on the electrode sheet and the standard span can be easily determined, thereby facilitating the determination of the difference between the location of the defective point on the defective electrode sheet and its allowable location. The electrode defect starting distance is the span between the defective point of the current electrode and its beginning end on the electrode tab. The electrode defect starting distance is used to calculate the distance between the defective point on the defective electrode and the beginning end of the electrode, so as to determine the length of the defective point on the defective electrode from the beginning end of the electrode, thereby making it easier to determine whether the defective point on the defective electrode is in a critical position of the electrode, and further making it easier to determine whether the defective point on the defective electrode has damaged the entire electrode. The second preset difference is a standard span difference, that is, the second preset difference is the standard distance between the defective point on the defective electrode and its first end. The second span difference matches the second preset difference, indicating that the span difference between the defective point on the defective electrode and its first end is within the safe range. This indicates that the defective point on the defective electrode is in a non-critical area of ​​the electrode, and that the defective point on the defective electrode is close to the first end cutting position of the electrode. A cutting signal is sent to the electrode tab defect identification system to die-cut the electrode end of the electrode tab, so that the defective electrode tab can be completely cut off and removed before winding.

[0043] When performing actual defective die-cutting on the tab strip, each electrode on the tab strip is usually coated with positive or negative electrode paste. The tab strip needs to be transported through multiple rollers. Before and after the transport through the rollers, the stress on the electrode will change. Small defects that are prone to appear on the electrode are easily covered by conductive paste, making it impossible to accurately identify the tiny defects on the electrode, which in turn leads to poor accuracy in marking defects on the electrode.

[0044] To further improve the accuracy of defect detection on the electrode tabs, the previous step of obtaining the defect span of the electrode tabs also included:

[0045] Obtain the first and second single-pole resistance values ​​of the tab band;

[0046] Detect whether the single resistance value of the first electrode is equal to the single resistance value of the second electrode;

[0047] When the resistance value of the first electrode is not equal to the resistance value of the second electrode, step S100 is executed.

[0048] In this embodiment, the first single-electrode resistance value and the second single-electrode resistance value are two different resistance values ​​of the same electrode during the transmission process. That is, the first single-electrode resistance value and the second single-electrode resistance value are two resistance values ​​of the same electrode before and after passing through the roller during the transmission process. In other words, the first single-electrode resistance value and the second single-electrode resistance value correspond to two different positions during the transmission process. Specifically, while performing appearance defect detection on each electrode of the electrode tab, the electrical performance of each electrode is tested twice before and after passing through the transmission roller to determine the resistance change of the same electrode before and after passing through the transmission roller, thereby facilitating the determination of the electrical conductivity of each electrode and, consequently, the determination of the minimum defects of each electrode. The fact that the resistance values ​​of the first and second electrodes are not equal indicates that the resistance of the current electrode of the tab belt changes abruptly after passing through the transmission roller. This means that the current electrode of the tab belt is torn after passing through the transmission roller, which also means that the current electrode of the tab belt has a defect after passing through the transmission roller. At this time, the defective electrode span of the tab belt can be directly obtained to mark and locate the electrode with the defect, further improving the marking accuracy of the defective marking position.

[0049] Furthermore, after obtaining the first and second single-pole resistance values ​​of the tab band, the method further includes the following steps:

[0050] The first electrical detection time is obtained based on the single resistance value of the first pole, and the second electrical detection time is obtained based on the single resistance value of the second pole.

[0051] Calculate the time difference between the first electrical inspection time and the second electrical inspection time;

[0052] Detect whether the electrical detection time difference is less than a preset time difference;

[0053] When the electrical inspection time difference is less than the preset time difference, a sampling signal is sent to the electrode defect identification system to collect the electrode defect starting distance and use it as the electrode defect span.

[0054] In this embodiment, the first electrical inspection time corresponds to the sampling time of the first electrode single resistance value, and the second electrical inspection time corresponds to the sampling time of the second electrode single resistance value. That is, the first electrical inspection time and the second electrical inspection time are the electrical performance testing times of the electrode sheet of the electrode tab before and after passing through the transmission roller. The electrical inspection time difference is the time difference between the first electrical inspection time and the second electrical inspection time, that is, the electrical inspection time difference is the electrical performance testing time difference of the electrode sheet of the electrode tab before and after passing through the transmission roller. The preset time difference is the transmission time between the defective point on the defective electrode sheet of the electrode tab and its beginning end. The electrical inspection time difference is less than the preset time difference, indicating that... The defective electrode on the tab strip will be normally transmitted to the laser die cutter. This indicates that when the defective electrode on the tab strip reaches the laser die cutter, the electrode has not yet completed the single-piece appearance defect detection. At this time, a sampling signal is sent to the electrode defect marking system to collect the electrode defect starting distance and use it as the electrode defect span. This ensures that when the defective electrode on the tab strip reaches the laser die cutter, the laser die cutter can promptly mark the position behind the defective point. This avoids determining the electrode defect span only after the defective point on the tab strip has passed the laser die cutter, thereby improving the accuracy of marking the defective position of the electrode.

[0055] In one embodiment, this application also provides a battery tab, including those prepared using the defective tab die-cutting method described in any of the above embodiments. In this embodiment, the defective tab die-cutting method includes obtaining the defective electrode span of the tab strip; performing cross-polarity standardization processing on the defective electrode span and a preset span to obtain the defective electrode span difference; and sending a defective electrode marking enable / disable signal to the tab defect marking system based on the defective electrode span difference to die-cut the defective electrode sheets on the tab strip. By collecting the defective electrode span, it is convenient to obtain the span of any electrode sheet with defects on the tab strip, perform cross-polarity standardization processing on it and a preset span to determine the specific positional difference of the defective electrode sheet within it, and finally determine the degree of damage to the electrode sheet by the defective electrode sheet based on the positional difference of the defective electrode sheet. This facilitates the marking of the defective electrode sheet and effectively improves the marking accuracy of the defective electrode sheet position.

[0056] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for die-cutting defective products with tabs, characterized in that, include: Obtain the single resistance value of the first pole and the single resistance value of the second pole of the tab; Detect whether the single resistance value of the first electrode is equal to the single resistance value of the second electrode; When the resistance of the first electrode is not equal to that of the second electrode, the electrode tab span of the electrode defective product is obtained. The defective electrode span is compared with the preset span by the cross-electrode standard deviation to obtain the defective span difference. Based on the aforementioned defective span difference, a defective marking enable / disable signal is sent to the electrode tab defective marking system to perform die-cutting on the defective electrode tab strip; The method of obtaining the first and second single-pole resistance values ​​of the electrode band further includes the following steps: The first electrical detection time is obtained based on the single resistance value of the first pole, and the second electrical detection time is obtained based on the single resistance value of the second pole. Calculate the time difference between the first electrical inspection time and the second electrical inspection time; Detect whether the electrical detection time difference is less than a preset time difference; When the electrical inspection time difference is less than the preset time difference, a sampling signal is sent to the electrode defect identification system to collect the electrode defect starting distance and use it as the electrode defect span.

2. The die-cutting method for electrode tabs according to claim 1, characterized in that, The process of obtaining the electrode strip defect span includes: Obtain the electrode defect spacing of the tab strip, where the electrode defect spacing is the distance between the defect point of the current electrode and its end in the tab strip.

3. The method for die-cutting electrode tabs according to claim 2, characterized in that, The step of performing cross-polarity standardization processing on the defective electrode span and the preset span to obtain the defective span amount includes: The difference between the electrode end spacing and the preset span is calculated to obtain the first span difference.

4. The method for die-cutting electrode tabs according to claim 3, characterized in that, The step of sending a cutting defect identification enable / disable signal to the electrode tab defect identification system according to the defect span difference, so as to die-cut the defective electrode sheet on the electrode tab strip, includes: Detect whether the first span difference matches the first preset difference; When the first span difference matches the first preset difference, a cutting signal is sent to the electrode defect identification system to die-cut the current electrode end of the electrode strip.

5. The die-cutting method for electrode tab defects according to claim 4, characterized in that, The step of detecting whether the first span difference matches the first preset difference further includes: When the first span difference does not match the first preset difference, a defective marking start signal is sent to the tab defect marking system to mark and die-cut the defective points on the tab.

6. The method for die-cutting defective products with tabs according to claim 5, characterized in that, When the first span difference does not match the first preset difference, a defective marking start signal is sent to the tab defect marking system to mark and die-cut the defective points on the tab tape. The process further includes: The end of the electrode sheet of the electrode tab is die-cut with endpoint reset.

7. The method for die-cutting electrode tabs according to claim 1, characterized in that, The process of obtaining the electrode strip defect span includes: Obtain the electrode defect start distance of the electrode tab, where the electrode defect start distance is the span between the defect point of the current electrode tab and its beginning end.

8. The method for die-cutting electrode tabs according to claim 7, characterized in that, The step of performing cross-polarity standardization processing on the defective electrode span and the preset span to obtain the defective span amount includes: The difference between the initial spacing of the electrode and the preset span is calculated to obtain the second span difference.

9. The method for die-cutting defective products with tabs according to claim 8, characterized in that, The step of sending a cutting defect identification enable / disable signal to the electrode tab defect identification system according to the defect span difference, in order to die-cut the defective electrode sheet on the electrode tab strip, includes: Detect whether the second span difference matches the second preset difference; When the second span difference matches the second preset difference, a cutting signal is sent to the electrode defect identification system to die-cut the electrode end of the electrode strip.

10. A battery tab, characterized in that, This includes products prepared using the die-cutting method for electrode blanks as described in any one of claims 1 to 9.

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