Calculation method of laser die cutting tool distance, laser die cutting method, pole piece and roll core

Abstract

The invention provides a laser die cutting cutter distance calculation method, a laser die cutting method, a pole piece and a roll core. The calculation method comprises the steps that the width Jn of a preset pole lug on the pole piece to be subjected to die cutting is determined; obtaining the thickness W1 of a positive pole piece to be wound, the thickness W2 of a negative pole piece to be wound, the thickness W3 of a diaphragm and the perimeter C of a winding needle; based on the principle that geometric center lines of a plurality of tabs with the same polarity on a roll core are aligned in the width direction after a pole piece to be subjected to die cutting is wound, when the pole piece to be subjected to die cutting is a positive pole piece, D1 positive = (C / pi + 4 * W3 + 2 * W2) * pi-J1 positive; when the pole piece to be die-cut is a negative pole piece, D1 negative = (C / pi + 2 * W3) * pi-J1 negative; dn-1 = [(Dn-2 + Jn-2) / Pi + 4 * W3 + 2 * (W1 + W2)] * Pi-Jn-1, and calculating the laser die cutting tool distance Dn-1 layer by layer. The problem that in the prior art, the die-cutting cutter distance of the pole piece is difficult to confirm is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery manufacturing, and in particular to a method for calculating a laser die-cutting blade distance, a laser die-cutting method, a pole piece, and a winding core. Background Art

[0002] Batteries are the core components of new energy vehicles, and their safety, reliability, and economy directly affect the performance and user experience of new energy vehicles. Among them, the tabs are the window for the internal materials of the battery to contact the outside world, and their quality is directly related to the electrical performance and safety performance of the battery.

[0003] For the initial production of new products, it is of vital importance to quickly determine the die-cutting size of the tabs, saving manpower and material resources and improving production efficiency. The traditional confirmation method is mainly through multiple cutting, and manually measuring the die-cutting size that needs to be adjusted according to the tab status of the core. Repeated confirmation is time-consuming and laborious, resulting in great material waste.

[0004] In order to optimize the confirmation of the die-cutting size of the pole piece, a study has proposed a pole lug edge positioning algorithm based on deep learning. This algorithm extracts features from the pole lug image through a convolutional neural network to achieve the pole lug edge positioning. However, this algorithm only solves the problem of pole lug edge positioning, and has poor control effects on key factors such as the pole lug die-cutting blade distance, and cannot effectively improve the cutting quality of lithium battery pole lugs. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for calculating the laser die-cutting blade distance, a laser die-cutting method, a pole piece, and a winding core, so as to solve the problem of quickly confirming the die-cutting size of the pole piece in the prior art.

[0006] In order to achieve the above object, according to one aspect of the present invention, a method for calculating the laser die cutting blade distance is provided, comprising determining the width J of the preset pole ear on the pole piece to be die cut n , n≥2, and n is a positive integer; where J 1 , J 2 , J 3 ,……,J n-1 , J n The widths of the first pole ear, the second pole ear, the third pole ear, ..., the n-1th pole ear, and the nth pole ear arranged in sequence from the innermost circle to the outermost circle of the winding core formed by the pole piece to be die-cut after winding are obtained; the thickness W of the positive pole piece to be wound is obtained. 1 , the thickness of the negative electrode W 2 , the thickness of the diaphragm W 3 , the circumference C of the winding needle; after the electrode piece to be die-cut is wound to form a winding core, the laser die-cutting blade distance D is calculated based on the principle of aligning the geometric center lines of multiple pole ears of the same polarity on the winding core in the width direction. 1, D 2 ,……,D n-2 , D n-1 , D 1 D is the laser cutting distance between the first and second tabs; n-1 is the laser cutting distance between the n-1th tab and the nth tab; where D 1 The calculation is: When the electrode to be die-cut is a positive electrode, then D 1正 =(C / π+4×W 3 +2×W 2 )×π-J 1正 ; When the electrode to be die-cut is a negative electrode, D 1负 =(C / π+2×W 3 )×π-J 1负 ;D n-1 The calculation of D is: n-1 =[(D n-2 +J n-2 ) / π+4×W 3 +2×(W 1 +W 2 )]×π-J n-1 ; Among them, calculate D n-1 , n≥3, and n is a positive integer.

[0007] Furthermore, when the width of the tab J 1 , J 2 , J 3 ,……,J n-1 , J n When the values ​​of are equal, the laser die cutting distance D 1 , D 2 ,……,D n-2 , D n-1 The value increases gradually.

[0008] Furthermore, when the width of the tab J 1 , J 2 , J 3 ,……,J n-1 , J n When the value of is gradually increasing, the laser die cutting distance D 1 , D 2 ,……,D n-2 , D n-1 The values ​​of are equal.

[0009] According to another aspect of the present invention, a laser die-cutting method is provided for laser die-cutting a pole piece to be die-cut according to the laser die-cutting blade distance obtained by the above-mentioned method for calculating the laser die-cutting blade distance.

[0010] According to another aspect of the present invention, a pole piece is provided, which is formed by laser die-cutting a pole piece to be die-cut according to the above-mentioned laser die-cutting method.

[0011] According to another aspect of the present invention, a winding core is provided, comprising the above-mentioned pole pieces, the pole pieces comprising a negative pole piece and a positive pole piece, the winding core comprising a winding layer, the winding layer being wound on the outer peripheral side of a winding needle, and in the radial direction of the winding needle, the winding layer comprises a diaphragm, a negative pole piece, a diaphragm, and a positive pole piece in sequence from the inside to the outside.

[0012] According to another aspect of the present invention, a battery is provided, comprising a winding core, wherein the winding core is the winding core described above.

[0013] Furthermore, the battery also includes a cover plate and a transfer plate, and the pole ears on the winding core are connected to the cover plate through the transfer plate.

[0014] Furthermore, the adapter plate includes a pole lug connection portion and a pole post connection portion, wherein the pole lug connection portion is connected to the pole lug on the winding core, and the pole post connection portion is connected to the pole post on the cover plate.

[0015] Furthermore, the battery also includes a shell, which is a hollow cavity with an opening at one end, the winding core is located in the shell, and the cover plate seals the opening of the shell.

[0016] The technical solution of the present invention provides a method for calculating the distance between laser die cutting blades, including determining the width J of the preset pole ear on the pole piece to be die cut. n , n≥2, and n is a positive integer; where J 1 , J 2 , J 3 ,……,J n-1 , J n The widths of the first pole ear, the second pole ear, the third pole ear, ..., the n-1th pole ear, and the nth pole ear arranged in sequence from the innermost circle to the outermost circle of the winding core formed by the pole piece to be die-cut after winding are obtained; the thickness W of the positive pole piece to be wound is obtained. 1 , the thickness of the negative electrode W 2 , the thickness of the diaphragm W 3 , the circumference C of the winding needle; after the electrode piece to be die-cut is wound to form a winding core, the laser die-cutting blade distance D is calculated based on the principle of aligning the geometric center lines of multiple pole ears of the same polarity on the winding core in the width direction. 1 , D 2 ,……,D n-2 , D n-1 , D 1 D is the laser cutting distance between the first and second tabs; n-1 is the laser cutting distance between the n-1th tab and the nth tab; where D 1 The calculation is: When the electrode to be die-cut is a positive electrode, then D1正 =(C / π+4×W 3 +2×W 2 )×π-J 1正 ; When the electrode to be die-cut is a negative electrode, D 1负 =(C / π+2×W 3 )×π-J 1负 ;D n-1 The calculation of D is: n-1 =[(D n-2 +J n-2 ) / π+4×W 3 +2×(W 1 +W 2 )]×π-J n-1 ; Among them, calculate D n-1 When n≥3, and n is a positive integer. This application simulates the winding core based on a simplified model and establishes the width J of the tab in a formulaic manner. n , Laser die cutting blade distance D n-1 , the thickness of the positive electrode W 1 , the thickness of the negative electrode W 2 , the thickness of the diaphragm W 3 , and the circumference C of the winding needle, which is beneficial to ensure the accuracy of die cutting, and the method is simple and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 A schematic diagram of a structure formed after a positive electrode sheet, a negative electrode sheet, and a separator are wound on a winding needle according to an optional embodiment of the present invention, and the electrode ears are omitted;

[0019] Figure 2 Shows Figure 1 A schematic diagram of the structure of the axial end surface;

[0020] Figure 3 A die-cutting schematic diagram taking a negative electrode sheet as an example according to an optional embodiment of the present invention is shown;

[0021] Figure 4 A schematic diagram of the structure of a wound positive and negative electrode sheets with electrode tabs according to an optional embodiment of the present invention is shown, in which the separator is omitted.

[0022] The above drawings include the following reference numerals:

[0023] 10. Winding needle; 20. Winding layer; 21. Separator; 22. Negative electrode sheet; 23. Positive electrode sheet; 24. Ear. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] In order to solve the problem of quickly confirming the die-cutting size of the pole piece in the prior art, the present invention provides a method for calculating the laser die-cutting blade distance, a winding core, a battery, and a laser die-cutting method. The battery includes a winding core, and the winding core is the above-mentioned winding core; the laser die-cutting method includes laser die-cutting the pole piece to be die-cut according to the above-mentioned method for calculating the laser die-cutting blade distance.

[0026] like Figures 1 to 4 As shown, the calculation method of laser die cutting blade distance includes:

[0027] Determine the width J of the preset pole ear 24 on the pole piece to be die-cut n , n≥2, and n is a positive integer; where J 1 , J 2 , J 3 ,……,J n-1 , J n They are respectively the widths of the first pole ear 24, the second pole ear 24, the third pole ear 24, ..., the n-1th pole ear 24, and the nth pole ear 24 arranged in sequence from the innermost circle to the outermost circle of the winding core formed by the pole piece to be die-cut after winding;

[0028] Obtain the thickness W of the positive electrode sheet 23 to be wound 1 , the thickness W of the negative electrode sheet 22 2 , the thickness W of the diaphragm 21 3 , the circumference C of the winding needle 10;

[0029] After the electrode piece to be die-cut is wound to form a core, the laser die-cutting blade distance D is calculated based on the principle of aligning the geometric center lines of multiple electrode ears 24 of the same polarity on the core in the width direction. 1 , D 2 ,……,D n-2 , D n-1 , D 1 D is the laser die cutting distance between the first pole ear 24 and the second pole ear 24; n-1is the laser die cutting distance between the n-1th pole tab 24 and the nth pole tab 24;

[0030] Among them, D 1 The calculation is: When the electrode to be die-cut is the positive electrode 23, then D 1正 =(C / π+4×W 3 +2×W 2 )×π-J 1正 When the electrode to be die-cut is the negative electrode 22, then D 1负 =(C / π+2×W 3 )×π-J 1负 ;

[0031] D n-1 The calculation of D is: n-1 =[(D n-2 +J n-2 ) / π+4×W 3 +2×(W 1 +W 2 )]×π-J n-1 ; Among them, calculate D n-1 , n≥3, and n is a positive integer.

[0032] The technical solution of the present invention provides a method for calculating the distance between laser die cutting blades. Based on a simplified model to simulate the core, the width J of the tab 24 is established in a formulaic manner. n , Laser die cutting blade distance D n-1 , the thickness of the positive electrode W 1 , the thickness of the negative electrode W 2 , the thickness of the diaphragm W 3 , and the circumference C of the winding needle, which is beneficial to ensure the accuracy of die cutting, and the method is simple and easy to implement.

[0033] It should be noted that in this application, the above-mentioned D 1正 The subscript "positive" in the above-mentioned D 1负 The subscript “negative” in denoted as negative electrode sheet 22 .

[0034] It is understandable that if Figure 3 and Figure 4 Indication: D 1 The laser die cutting distance between the first pole ear 24 of the innermost circle and the second pole ear 24 adjacent thereto. Since the separator 21, the negative pole piece 22, the separator 21 and the positive pole piece 23 are usually arranged on the winding needle 10 from the inside to the outside, the D 1 is different, at this time D 1 The calculation of needs to be divided into two cases:

[0035] For the negative electrode sheet 22, since there is only one layer of diaphragm 21 between the first negative electrode tab 24 and the winding needle, D1 负 =(diameter of winding needle 10 + 2*thickness of diaphragm 21)×π-J 1负 , i.e. D1 负 =(C / π+2*W 3 )×π-J 1负 ;

[0036] For the positive electrode sheet 23, since there are two layers of diaphragms 21 and one layer of negative electrode sheet 22 between the first positive electrode tab 24 and the winding needle, D 1正 =(diameter of winding needle 10 + 4*thickness of separator 21 + 2*thickness of negative electrode sheet 22)×π-J 1正 , that is, D 1正 =(C / π+4*W 3 +2*W 2 )×π-J 1正 .

[0037] For D n-1 , and when n ≥ 3, in order to reduce the error, D can be used n-1 and D n-2 In addition, in this case, the D of the positive electrode sheet 23 and the negative electrode sheet 22 n-1 and D n-2 The relationship between them is the same, so there is no need to distinguish between the positive electrode sheet 23 and the negative electrode sheet 22. n-1 and D n-2 There is a negative electrode sheet 22, a positive electrode sheet 23 and two separators 21 between them, thereby establishing D n-1 and D n-2 The relationship between them is as follows:

[0038] D n-1(n≥3) =[(D n-2 +J n-2 ) / π+4*thickness of the separator 21+2*(thickness of the positive electrode sheet 23+thickness of the negative electrode sheet 22)]×π-J n-1 ; i.e. D n-1 =[(D n-2 +J n-2 ) / π+4×W 3 +2×(W 1 +W 2 )]×π-J n-1 .

[0039] Therefore, calculate D 2 When D 2 =[(D 1 +J 1 ) / π+4×W3 +2×(W 1 +W 2 )]×π-J 2 Similarly, D 3 , D 4 ……、D n-2 , D n-1 The same is true.

[0040] Specifically, in actual calculations, for simplicity, the value of π can be taken as 3.14.

[0041] In some embodiments, when the width J of the tab 24 is 1 , J 2 , J 3 ,……,J n-1 , J n When the values ​​of are equal, the laser die cutting distance D 1 , D 2 ,……,D n-2 , D n-1 The value increases gradually.

[0042] In some embodiments, when the width J of the tab 24 is 1 , J 2 , J 3 ,……,J n-1 , J n When the value of is gradually increasing, the laser die cutting distance D 1 , D 2 ,……,D n-2 , D n-1 The values ​​of are equal.

[0043] In some embodiments, the laser die cutting distance also includes B and D E ,like Figure 3 Schematic diagram, DB is the distance between the pole piece winding start side and the first pole ear 24, and naturally D E D is the distance between the pole piece winding end side and the last pole ear 24. Specifically, D B and D E It can be adjusted according to the specific requirements of the product (i.e. mainly from the design input), for example, some models of winding core require D B Insertion position and D E The end position is at the corner of the core (R angle), and D B and D E It is also related to the margin requirements of the positive and negative electrode tabs 24 and the width of the tabs 24. That is, in fact, D B , D EThe width of the tab 24 on the positive electrode sheet 23 and the width of the tab 24 on the negative electrode sheet 22 are determined according to the requirements of specific products.

[0044] Applying the technical solution of the present invention, the present application provides a laser die-cutting method for laser die-cutting a pole piece to be die-cut according to the laser die-cutting blade distance obtained by the above-mentioned and below-mentioned methods for calculating the laser die-cutting blade distance.

[0045] By applying the technical solution of the present invention, the present application provides a pole piece, which is used to form a pole piece to be die-cut by laser die-cutting according to the above-mentioned laser die-cutting method.

[0046] Applying the technical solution of the present invention, the present application provides a winding core, including the above-mentioned pole pieces, the pole pieces include a negative pole piece 22 and a positive pole piece 23, the winding core includes a winding layer 20, the winding layer 20 is wound on the outer peripheral side of the winding needle 10, and in the radial direction of the winding needle 10, the winding layer 20 includes a diaphragm 21, a negative pole piece 22, a diaphragm 21, and a positive pole piece 23 from the inside to the outside.

[0047] Specifically, the schematic diagram of the winding core is as follows Figure 2 As shown, the center hole is formed after the winding needle 10 is removed. Figure 2 It can be seen that during the winding process, the first thing to contact the winding needle 10 is the diaphragm 21, and outside the diaphragm 21 is the negative electrode sheet 22, then the diaphragm 21, then the positive electrode sheet 23, and then the diaphragm 21, and so on, a layer of diaphragm 21, a layer of negative electrode sheet 22, a layer of diaphragm 21, a layer of positive electrode sheet 23, and the cycle is repeated. The specific winding core with the pole ear 24 is as follows: Figure 4 Hint: Figure 4 The three tabs 24 on the lower left side are positive tabs 24. Figure 4 The four electrode tabs 24 on the lower right side of the center are negative electrode tabs 24 .

[0048] like Figure 1 As shown, when winding, it includes a winding needle 10 and a winding layer 20. The winding layer 20 is wound on the outer peripheral side of the winding needle 10, and in the radial direction of the winding needle 10, the winding layer 20 includes a separator 21, a negative electrode sheet 22, a separator 21, and a positive electrode sheet 23 from the inside to the outside.

[0049] Applying the technical solution of the present invention, the present application provides a battery, including a winding core, which is the winding core described above.

[0050] In one embodiment, the battery further includes a cover plate and a transfer sheet, and the tabs 24 on the winding core are connected to the cover plate via the transfer sheet.

[0051] In one embodiment, the adapter plate includes a pole lug 24 connection portion and a pole post connection portion, wherein the pole lug 24 connection portion is connected to the pole lug 24 on the winding core, and the pole post connection portion is connected to the pole post on the cover plate.

[0052] In one embodiment, the battery further includes a shell, which is a hollow cavity with an opening at one end, the winding core is located in the shell, and the cover plate seals the opening of the shell.

[0053] The present application provides a method for calculating the laser die cutting blade distance, including determining the width J of the preset pole ear 24 on the pole piece to be die cut. n , n≥2, and n is a positive integer; where J 1 , J 2 , J 3 ,……,J n-1 , J n The widths of the first pole ear 24, the second pole ear 24, the third pole ear 24, ..., the n-1th pole ear 24, and the nth pole ear 24 are arranged in sequence from the innermost circle to the outermost circle of the winding core formed after the die-cut pole piece is wound; the thickness W of the positive pole piece to be wound is obtained 1 , the thickness of the negative electrode W 2 , the thickness of the diaphragm W 3 , the circumference C of the winding needle; based on the principle of aligning the geometric center lines of multiple pole ears 24 of the same polarity on the winding core in the width direction after the pole piece to be die-cut is wound, calculate the laser die-cutting blade distance D 1 , D 2 ,……,D n-2 , D n-1 , D 1 D is the laser die cutting distance between the first pole ear 24 and the second pole ear 24; n-1 is the laser die cutting distance between the n-1th pole ear 24 and the nth pole ear 24; wherein, D 1 The calculation of D is: When the electrode to be die-cut is a positive electrode, 1正 =(C / π+4*W 3 +2*W 2 )×π-J 1正 When the electrode to be die-cut is a negative electrode, D 1负 =(C / π+2*W 3 )×π-J 1负 ;D n-1 The calculation of D is: n-1 =[(D n-2 +J n-2 ) / π+4×W 3 +2×(W 1 +W 2 )]×π-J n-1 ; Among them, calculate D n-1 When n≥3, and n is a positive integer. The present invention simulates the winding core based on a simplified model and establishes the width J of the tab 24 in a formulaic manner. n, Laser die cutting blade distance D n-1 , the thickness of the positive electrode W 1 , the thickness of the negative electrode W 2 , the thickness of the diaphragm W 3 , and the circumference C of the winding needle, which is beneficial to ensure the accuracy of die cutting, and the method is simple and easy to implement.

[0054] The calculation method of the laser die-cutting blade distance provided in this application effectively improves the accuracy and efficiency of the laser die-cutting process through accurate parameter acquisition and dynamic size calculation. The application of this method not only optimizes the die-cutting process, but also significantly improves the quality of the tabs in the battery manufacturing process, providing a strong guarantee for the stability and safety of battery performance. In practical applications, this method can significantly improve the production efficiency of batteries, reduce production costs, and at the same time ensure the high performance and high reliability of batteries, providing advanced technical support for battery manufacturing in the fields of new energy vehicles, energy storage equipment, etc. Especially under the trend of precision and automation in battery manufacturing, the implementation effect of this method is more significant, and it can effectively respond to various challenges in the battery manufacturing process and promote the continuous progress of battery manufacturing technology.

[0055] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0056] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0057] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0058] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0059] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for calculating the distance between blades of laser die cutting, characterized in that: include: Determine the width J of the preset pole ear (24) on the pole piece to be die-cut n , n≥2, and n is a positive integer; where J1, J2, J3, ..., J n-1 , J n They are respectively the widths of the first pole ear (24), the second pole ear (24), the third pole ear (24), ..., the n-1th pole ear (24), and the nth pole ear (24) arranged in sequence from the innermost circle to the outermost circle of the winding core formed by winding the pole piece to be die-cut; Obtaining the thickness W1 of the positive electrode sheet (23) to be wound, the thickness W2 of the negative electrode sheet (22), the thickness W3 of the separator (21), and the circumference C of the winding needle (10); After the electrode piece to be die-cut is wound to form the winding core, based on the principle of aligning the geometric center lines of multiple electrode ears (24) of the same polarity on the winding core in the width direction, the laser die-cutting blade distances D1, D2, ..., D n-2 , D n-1 , D1 is the laser die cutting distance between the first pole ear (24) and the second pole ear (24); D n-1 is the laser die cutting distance between the n-1th pole lug (24) and the nth pole lug (24); Wherein, D1 is calculated as follows: When the electrode piece to be die-cut is the positive electrode piece (23), then D 1正 =(C / π+4×W3+2×W2)×π-J 1正 When the electrode to be die-cut is the negative electrode (22), then D 1负 =(C / π+2×W3)×π-J 1负 ; D n-1 The calculation of D is: n-1 =[(D n-2 +J n-2 ) / π+4×W3+2×(W1+W2)]×π-J n-1 ; Among them, calculate D n-1 , n≥3, and n is a positive integer.

2. The method for calculating the laser die cutting distance according to claim 1, characterized in that: When the widths J1, J2, J3, ..., J n-1 , J n When the values ​​of are equal, the laser die cutting distances D1, D2, ..., D n-2 , D n-1 The value increases gradually.

3. The method for calculating the laser die cutting distance according to claim 1, characterized in that: When the widths J1, J2, J3, ..., J n-1 , J n When the value of is gradually increasing, the laser die cutting distances D1, D2, ..., D n-2 , D n-1 The values ​​of are equal.

4. A laser die cutting method, characterized in that: The laser die-cutting blade distance obtained by the method for calculating the laser die-cutting blade distance according to any one of claims 1 to 3 is used to laser die-cut the pole piece to be die-cut.

5. A pole piece, characterized in that: It is formed by laser die-cutting the pole piece to be die-cut by the laser die-cutting method according to claim 4.

6. A winding core, characterized in that: The invention comprises the pole piece according to claim 5, wherein the pole piece comprises a negative pole piece (22) and a positive pole piece (23), and the winding core comprises: A winding layer (20), the winding layer (20) is wound around the outer circumference of the winding needle (10), and in the radial direction of the winding needle (10), the winding layer (20) includes, from the inside to the outside, a separator (21), the negative electrode sheet (22), the separator (21), and the positive electrode sheet (23).

7. A battery, characterized in that: It comprises a winding core, wherein the winding core is the winding core according to claim 6.

8. The battery according to claim 7, characterized in that The battery also includes a cover plate and a transfer plate, and the pole lug (24) on the winding core is connected to the cover plate via the transfer plate.

9. The battery according to claim 8, characterized in that The adapter plate comprises a pole lug connection portion and a pole column connection portion, wherein the pole lug connection portion is connected to the pole lug (24) on the winding core, and the pole column connection portion is connected to the pole column on the cover plate.

10. The battery according to claim 9, characterized in that The battery further comprises a shell, which is a hollow cavity with an opening at one end. The winding core is located in the shell, and the cover plate seals the opening of the shell.

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