Positioning method for multiple tabs of electrode plate

Abstract

The invention discloses a method for positioning multiple tabs of an electrode plate, and belongs to the technical field of batteries. The method comprises the following steps: alternately arranging a plurality of active material areas and a plurality of empty foil areas on a pole piece in a direction from a winding starting end to a winding ending end of the pole piece; the length of the active material area along the alternate arrangement direction is Ln, and the width of the empty foil area along the alternate arrangement direction is Dn; the empty foil area is used for tab welding or rubberizing; at least two Ln are different, and at least two Dn are the same or at least two Dn are different; the first positioning method comprises the steps that when at least two Dn are different, each Dn is detected, and when it is detected that the Dn is the preset width I, the empty foil area is positioned as a tab welding position or a rubberizing position; the second method comprises the following steps: when at least two Dn are the same, detecting each Ln and Dn adjacent to the Ln; and when the Ln is detected to be the preset length II and the Dn adjacent to the Ln is greater than 0, positioning the empty foil area as a tab welding or rubberizing position. According to the method, the multi-tab welding position can be accurately positioned.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a method for positioning multiple pole tabs of an electrode plate. Background Art

[0002] Winding is one of the most important processes in the manufacturing process of cylindrical batteries and is crucial to the performance of the battery. The winding of cylindrical batteries generally includes positive and negative electrode sheets and upper and lower separators. The negative electrode, upper separator, positive electrode and lower separator are wound in sequence. The gap coating of the positive and negative electrode sheets requires ear welding and post-welding ear gluing during the winding process. In order to ensure the correct position of the ear welding and gluing, it is necessary to detect and locate the welding position and the gluing position. When there is only one gap between the positive and negative electrode sheets of a single EA, the welding and gluing positions are determined by detecting the material area and the edge of the foil, which can realize the welding and gluing function of the positive and negative single-electrode ears. When there are multiple gaps between the positive and negative electrode sheets of a single EA (≥2), the welding position and gluing position detection and determination of the two different ears cannot be met, which not only greatly restricts the battery design but also makes it impossible to improve the performance of the battery, seriously affecting the rapid development of the battery.

[0003] The application of cylindrical batteries in the new energy industry is becoming more and more common. The performance, life and safety of batteries have been in need of improvement. The winding process of cylindrical battery manufacturing is the most important influencing factor. The existing winding pole ear welding glue can only identify the single pole ear detection and positioning mode, and cannot realize the multi-pole ear welding glue detection and positioning. Summary of the invention

[0004] The main purpose of the present application is to provide a method for positioning multiple tabs of an electrode pole piece, so as to solve the problem in the prior art that it is impossible to accurately position, weld and glue the multiple tabs in the pole piece.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a method for positioning multiple tabs of an electrode plate is provided, wherein multiple active material areas and multiple empty foil areas are alternately arranged on the electrode plate along the direction from the starting end to the ending end of the winding of the electrode plate; the length of the active material area along the direction of the alternating arrangement is L n , the width of the empty foil area along the alternating direction is D n ; The empty foil area is used for electrode welding or gluing; the length of at least two active material areas is L n Different, and at least two empty foil areas have a width D n The same or different; wherein the positioning method includes:

[0006] Method 1: When the width D of at least two empty foil areas n At the same time, the width D of each empty foil area is detected n ; When the width D of the empty foil area is detected n When the preset width is I, the empty foil area is positioned as the tab welding position or the glue pasting position;

[0007] Method 2: When the width D of at least two empty foil areas n At the same time, detect the length L of each active material area n and the width D of the adjacent empty foil area n ; When the length L of the active material area is detected n When the preset length is II, the width D of the adjacent empty foil area is n When it is greater than 0, the empty foil area adjacent to the active material area is positioned as the tab welding position or the glue pasting position.

[0008] Furthermore, the detection device is a detection sensor capable of identifying the boundary between the empty foil area and the active material area, and the detection length is obtained according to the detection time and detection speed output by the detection sensor.

[0009] Furthermore, the detecting device is a reflective sensor.

[0010] Furthermore, the detection device is arranged in parallel with the electrode plate, and the distance between the two is 0.5 mm to 50 mm.

[0011] Further, the empty foil region adjacent to the active material region is an adjacent empty foil region located downstream of the active material region along the winding direction.

[0012] Furthermore, in method 1, the width D of the plurality of empty foil areas provided on the electrode plate is n Are all different.

[0013] Furthermore, in the second method, the width D of the empty foil area provided on the electrode plate is n are the same and the length of the active material zone L n Are all different.

[0014] Furthermore, among the multiple active material areas and empty foil areas alternately arranged on the electrode plate, the width D of a portion of the empty foil areas is n The width D of the remaining empty foil area is the same as n Different, and the length L of at least two active material zones n Not the same.

[0015] Furthermore, the number of the empty foil areas provided on the electrode piece is 3 to 8; the width D of the empty foil area n 6~20mm.

[0016] Furthermore, the number of the pole tabs is 3 to 5; the number of the pole tabs is less than or equal to the number of the empty foil areas; and the width of the pole tabs is 3 to 6 mm.

[0017] By applying the technical solution of the present application, a method for welding and positioning multiple tabs of an electrode plate is provided. By utilizing the arrangement of different lengths of multiple active material areas and empty foil areas, different length detection strategies are adopted respectively and in a targeted manner. The empty foil positions where tabs need to be welded or tabs need to be glued can be accurately located, thereby increasing the service life and safety of the battery and improving the overall performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 A schematic diagram showing the relative positions of the detection device and the pole piece in the embodiment of the present application is shown;

[0020] Figure 2 A schematic diagram showing the positions of the active material area and the empty foil area of ​​the electrode in Example 1 of the present application is shown;

[0021] Figure 3 A schematic diagram showing the positions of the active material area and the empty foil area of ​​the electrode in Example 2 of the present application is shown;

[0022] Figure 4 A schematic diagram showing the positions of the active material area and the empty foil area of ​​the electrode in Example 3 of the present application is shown;

[0023] Figure 5 A schematic diagram showing the positions of the active material area and the empty foil area of ​​the electrode in Example 4 of the present application is shown.

[0024] Reference numerals:

[0025] 1. Pole piece; 2. Starting end; 3. Ending end; 4. Active material area; 5. Empty foil area; 6. Winding direction; 7. Detection sensor. DETAILED DESCRIPTION

[0026] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0027] As mentioned in the background art, the prior art cannot accurately locate the target electrode welding or gluing position from multiple electrodes, which seriously affects the battery performance. Therefore, this application mainly aims at accurately locating a multi-electrode electrode sheet with at least two electrodes in the electrode sheet to facilitate electrode welding and gluing.

[0028] According to one aspect of the present application, a method for positioning multiple pole tabs of an electrode plate is provided, comprising:

[0029] Along the direction from the starting end to the ending end of the electrode sheet winding, multiple active material areas and multiple empty foil areas are alternately arranged on the electrode sheet; the length of the active material area along the direction of alternating arrangement is L n , the width of the empty foil area along the alternating direction is D n ; The empty foil area is used for electrode welding or gluing; the length of at least two active material areas is L n Different, and at least two empty foil areas have a width D n Width D of the same or at least two empty foil areas n different;

[0030] Among them, the positioning methods include:

[0031] Method 1: When the width D of at least two empty foil areas n At the same time, the width D of each empty foil area is detected n , when the width D of the empty foil area is detected n When the preset width is I, the empty foil area is positioned as the tab welding position or the glue pasting position;

[0032] Method 2: When the width D of at least two empty foil areas n At the same time, detect the length L of each active material area n and the width D of the adjacent empty foil area n ; When the length L of the active material area is detected n When the preset length is II, the width D of the adjacent empty foil area is n When it is greater than 0, the empty foil area adjacent to the active material area is positioned as the tab welding position or the glue pasting position.

[0033] The multi-electrode tabs of the present application are at least two; the number of active material areas and empty foil areas is not limited, and the lengths of the active material areas and the empty foil areas are alternately arranged and can be expressed as L1-D1-L2-D2-L3-...L n -D n; The positioning method of the present application is to select a target width that is the same as the preset width from n widths D, and use the empty foil area with the target width as the positioning area for welding the pole ear or sticking the pole ear glue on the empty foil; generally, there are at least two active material areas set on the electrode pole piece, and the lengths are different, and there are at least two empty foil areas set. It is possible that the widths of all empty foil areas are the same, or the widths of all empty foil areas are different, and it is also possible that among multiple empty foil areas, a part of the empty foil areas have the same width, and the widths of the remaining part of the empty foil areas are different; when selecting a suitable empty foil width, the above situations will be targeted. One is that the empty foil widths are different. As long as the empty foil widths are detected one by one, the empty foil areas with the same preset width I are selected as the target area according to the detection value; the second situation is that the empty foil widths are the same. In this case, the detected widths are all the same, that is, the target empty foil area cannot be selected according to the empty foil width detection value. At this time, according to the conventional situation in this field, most of the lengths of the active material areas Under unequal conditions, the position of each active material area can be distinguished by detecting the length of the active material area, and then the target empty foil area can be indirectly screened out from the empty foil area adjacent to it. In this detection process, the length of the active material area is detected to screen the active material area that meets the preset length II, and the width of the empty foil area is detected to determine whether there is an empty foil area in the adjacent position of the active material area and to accurately locate the width of the empty foil area; the above-mentioned preset width I is specifically the preset width of the empty foil. According to the conventional settings in this field, the preset width is generally greater than the width of the pole ear, or less than the width to be glued; the above-mentioned preset length II is specifically the preset length of the active material area, and the preset length is generally greater than the width of the empty foil; the above-mentioned empty foil area adjacent to the active material area can be an empty foil area located downstream along the winding direction of the pole piece, or it can be an empty foil area located upstream along the winding direction of the pole piece; the equipment used for the above-mentioned detection can be used as long as it can directly measure or indirectly calculate the length of the material area or the width of the foil area, and the type is not limited. This application adopts different detection strategies according to the arrangement of different lengths and widths of multiple active material areas and empty foil areas, accurately locates the target empty foil positions that require tab welding or tab gluing, and also improves the battery life and safety and enhances the overall performance of the battery.

[0034] In some embodiments, the detection device is a detection sensor capable of identifying the boundary between the empty foil area and the active material area, and the detection length is obtained according to the detection time and detection speed output by the detection sensor; for example, a reflective sensor, specifically LR-X50.

[0035] The above-mentioned detection sensor selected in the present application is an existing device in the field, which has the function of identifying the boundary between the material area or the empty foil area according to the different colors of the two areas, and can output the specific identification time and the equipment operation speed during the identification process; the detection sensor equipment of this profession is conventionally used to determine which part of the electrode is coated with active material and which part is not coated but is an empty foil area, and has never been used to detect the length of the material area or the empty foil area of ​​the electrode; and the present application takes into account the functions of the detection sensor itself, and properly utilizes the idea that it can output the identification time and operation speed and then calculate the operation distance, which can not only accurately obtain the length of the detection area, but also make full use of the existing equipment, avoid the selection of other types of detection equipment, and save equipment costs.

[0036] In some embodiments, the detection device is arranged in parallel with the electrode plate, and the distance between the two is 0.5 mm to 50 mm. The present application can ensure the accuracy of the detection result by arranging the detection device in parallel and limiting the detection distance.

[0037] In some embodiments, the preset width I is the preset width of the empty foil area. The preset width I can be multiple, and the number is not limited. It is generally the same as the number of pole ears to be welded, or the same as the number of adhesives. Due to the different widths of the pole ears, each preset width I is also different; the preset length II is the length of the active material area, and the number is not limited. The number is the same as the number of pole ears, and the length of the preset length II is also different. This application needs to find an empty foil area with the same preset width I from multiple empty foil areas of different widths as the target area, and then weld the pole ears or adhesive; and in the case where the lengths of the corresponding active material areas are different and the lengths of the empty foil areas are the same, it is necessary to find an active material area with the same preset length II from multiple active material layers of different lengths, and use the empty foil area adjacent to the material area as the target area, and then weld the pole ears or adhesive.

[0038] In some embodiments, the empty foil region adjacent to the active material region is an adjacent empty foil region located downstream of the active material region along the winding direction.

[0039] The active material area mentioned in the present application downstream along the winding direction specifically refers to the downstream in the direction from the starting end to the ending end of the winding; the customary operation in this field is also to locate the empty foil area adjacent to the active material area downstream along the winding direction by measuring the length of the active material area.

[0040] In some embodiments, in method 1, among the multiple active material areas and multiple empty foil areas alternately arranged on the electrode plate, the width D of each empty foil area is n Are all different.

[0041] The width of the empty foil area arranged in the above-mentioned electrode piece of the present application is different, and the target empty foil that meets the requirements can be screened by detecting the width of the empty foil area.

[0042] In some embodiments, in method 2, among the multiple active material areas and multiple empty foil areas alternately arranged on the electrode plate, the width D of the empty foil area is n The length L of the active material zone adjacent to it is the same n The length of the active material area set in the above-mentioned electrode of the present application should be different, and the empty foil area on the adjacent side can be screened to see whether it is the target foil area by detecting the length of the material area.

[0043] In some embodiments, among the multiple active material areas and multiple empty foil areas alternately arranged on the electrode plate, the width D of a portion of the empty foil areas is n The length L of the active material zone that is the same as and adjacent to it n The width D of the remaining empty foil area is different. n The above-mentioned pole piece of the present application includes both empty foil areas with the same width and empty foil areas with different widths. For the empty foil areas with the same width, the lengths of the active material areas adjacent thereto should be different.

[0044] In some embodiments, the number of empty foil areas provided on the electrode piece is 3 to 8. The number of empty foil areas in the electrode piece of the present application can be set according to actual needs.

[0045] In some embodiments, the width D of the empty foil area provided on the electrode piece is n The width of the empty foil area in the above-mentioned electrode of the present application can be set according to actual needs.

[0046] In some embodiments, the number of the tabs is 3 to 5; the number of the tabs is less than or equal to the number of the empty foil areas; and the width of the tabs is 3 to 6 mm.

[0047] The above-mentioned electrode plate of the present application can be a positive electrode plate or a negative electrode plate, can be an electrode plate of a lithium battery, or can be an electrode plate of other types. The above-mentioned detection method of the present application can be applied to the multi-ear positioning welding or gluing of various types of battery plates.

[0048] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0049] Example 1

[0050] An electrode plate 1, along the direction from the starting end 2 to the ending end 3 of the winding, 6 active material areas 4 and 5 empty foil areas 5 are alternately arranged on the electrode plate 1; the length of the active material area along the direction of alternating arrangement is L n , the width of the empty foil area along the alternating direction is D n ; The length of each area of ​​the pole piece is arranged as L1-D1-L2-D2-L3-D3-L4-D4-L5-D5-L6; The length of each active material area in the pole piece is L nThe width D of each empty foil area is different. n are all different; the widths of the electrode ears to be welded are 3mm, 4mm, and 5mm respectively; 3 target empty foils need to be screened out from the 5 empty foil areas D1 to D5, and the preset widths of the 3 target empty foils are 6mm, 8mm, and 10mm respectively; the electrode structure is as follows Figure 2 As shown;

[0051] Install the LR-X50 detection sensor 7 parallel to the electrode plate, with a distance of 2 mm between them. Figure 1 As shown; start the equipment, the detection sensor runs from the starting end to the ending end of the electrode, and completes the boundary scanning and identification of 6 active material areas and 5 empty foil areas in turn; the detection time and detection rate of the sensor for each empty foil area are recorded in turn, and according to distance = time x rate, the widths D1, D2, D3, D4, and D5 of the 5 empty foil areas are calculated in turn to be 6mm, 12mm, 8mm, 10mm, and 13mm respectively; the first empty foil area, the third empty foil area, and the fourth empty foil area are selected to meet the requirements, corresponding to the welding of 3mm, 4mm, and 5mm widths of the electrode ears.

[0052] Example 2

[0053] An electrode plate 1, along the direction from the starting end 2 to the ending end 3 of the winding, 5 active material areas 4 and 4 empty foil areas 5 are alternately arranged on the electrode plate 1; the length of the active material area along the direction of alternating arrangement is L n , the width of the empty foil area along the alternating direction is D n ; The length of each area of ​​the pole piece is arranged as L1-D1-L2-D2-L3-D3-L4-D4-L5; The length of each active material area in the pole piece is L n are different, the width of each empty foil area is the same, D n =8mm; it is necessary to weld two tabs on the empty foil area adjacent to the active material layer with preset lengths of 25mm and 30mm respectively along the winding direction, and the width of the tabs is 4mm; it is necessary to select two active material areas that meet the target length from the five active material areas; the pole piece structure is as follows Figure 3 As shown;

[0054] Install the LR-X50 detection sensor 7 parallel to the electrode plate, with a distance of 2 mm between them. Figure 1As shown; start the equipment, the detection sensor runs from the starting end to the ending end of the electrode piece, and completes the boundary scanning and identification of 5 active material areas and 4 empty foil areas in turn; the detection time and detection rate of the sensor for each active material area are recorded in turn, and according to distance = time x rate, the lengths L1, L2, L3, L4, and L5 of the 5 active material areas are calculated in turn to be 20mm, 25mm, 28mm, 30mm, and 35mm respectively; from the detection data, it can be seen that the lengths of the second active material area and the fourth active material area meet the requirements, so one pole ear is welded on the second empty foil area D2 adjacent to the second active material area on one side along the winding direction and the fourth empty foil area D4 adjacent to the fourth active material area on one side along the winding direction.

[0055] Example 3

[0056] An electrode plate 1, along the direction from the starting end 2 to the ending end 3 of the winding, 9 active material areas 4 and 8 empty foil areas 5 are alternately arranged on the electrode plate 1; the length of the active material area along the direction of alternating arrangement is L n , the width of the empty foil area along the alternating direction is D n ; The length of each area of ​​the pole piece is arranged as L1-D1-L2-D2-L3-D3-L4-D4-L5-D5-L6-D6-L7-D7-L8-D8-L9; The length of each active material area in the pole piece is L n The width of each empty foil area in L1-D1-L2-D2-L3-D3-L4-D4-L5-D5 is different, and the width of each empty foil area in L6-D6-L7-D7-L8-D8-L9 is the same. n =12mm; it is necessary to select three target empty foils that meet the requirements from D1 to D5, the preset widths of the target empty foils are 6mm, 8mm, and 10mm, and the welding tab widths are 3mm, 4mm, and 5mm, respectively; it is necessary to weld two tabs in the empty foil area adjacent to the active material layer of preset lengths of 25mm and 30mm along the winding direction, and the tab widths are both 6mm; it is necessary to select two active material areas that meet the target length from the four active material areas of L6 to L9; the pole piece structure is as follows Figure 4 As shown;

[0057] Install the LR-X50 detection sensor 7 parallel to the electrode plate, with a distance of 3 mm between them. Figure 1As shown; start the equipment, the detection sensor runs from the starting end to the ending end of the electrode, and completes the boundary scanning and identification of 9 active material areas and 8 empty foil areas in sequence; the detection time and detection rate of the sensor for each empty foil area D1 to D5 are recorded in sequence, and according to distance = time x rate, the widths of the 5 empty foil areas D1, D2, D3, D4, and D5 are calculated in sequence to be 6mm, 12mm, 8mm, 10mm, and 13mm respectively, from which the first empty foil area, the third empty foil area, and the fourth empty foil area are selected to meet the requirements Calculate and weld 3 pole ears; record the detection time and detection rate of each active material area in turn, and according to distance = time x rate, calculate the lengths of the 4 active material areas L6, L7, L8, and L9 to be 28mm, 25mm, 30mm, and 20mm respectively; the lengths of the seventh active material area and the eighth active material area meet the requirements, so weld 1 pole ear each at the seventh empty foil area D7 adjacent to the seventh active material area along the winding direction and the eighth empty foil area D8 adjacent to the eighth active material area along the winding direction.

[0058] Example 4

[0059] An electrode plate 1, along the direction from the starting end 2 to the ending end 3 of the winding, 4 active material areas 4 and 3 empty foil areas 5 are alternately arranged on the electrode plate 1; the length of the active material area along the direction of alternating arrangement is L n , the width of the empty foil area along the alternating direction is D n ; The length of each area of ​​the pole piece is arranged as L1-D1-L2-D2-L3-D3-L4; The length of each active material area in the pole piece is L n The width D of each empty foil area is different. n are all different; the widths of the pole ears to be welded are 3mm, 4mm, and 5mm respectively; the pole ears of corresponding widths need to be welded in the three empty foil areas D1 to D3, and the preset widths of the three empty foil areas are 6mm, 8mm, and 10mm respectively. The pole piece structure is as follows Figure 5 As shown;

[0060] Install the LR-X50 detection sensor 7 parallel to the electrode plate, with a distance of 2 mm between them. Figure 1 As shown; start the equipment, the detection sensor runs from the starting end to the ending end of the electrode, and completes the boundary scanning and identification of 4 active material areas and 3 empty foil areas in turn; the detection time and detection rate of the sensor for each empty foil area are recorded in turn, and according to distance = time x rate, the widths D1, D2, and D3 of the three empty foil areas are calculated in turn to be 8mm, 6mm, and 10mm respectively; according to the specific lengths of the empty foil areas, it is judged that the first empty foil area has a welding width of 4mm for the electrode lug, the second empty foil area has a welding width of 3mm for the electrode lug, and the third empty foil area has a welding width of 5mm for the electrode lug.

[0061] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those described herein, for example.

[0062] The above description is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for positioning multiple tabs of an electrode plate, characterized in that: Along the direction from the starting end to the ending end of the winding of the electrode sheet, a plurality of active material areas and a plurality of empty foil areas are alternately arranged on the electrode sheet; the length of the active material area along the direction of the alternating arrangement is L n The width of the empty foil area along the alternating direction is D n ; The empty foil area is used for electrode ear welding or gluing; the length L of at least two of the active material areas n different, and the width D of at least two of the empty foil areas n The same or different; wherein the positioning method includes: Method 1: When the width D of at least two of the empty foil areas n At the same time, the width D of each of the empty foil areas is detected. n When the width D of the empty foil area is detected n When the width is preset to I, the empty foil area is positioned as a tab welding position or a glue pasting position; Method 2: When the width D of at least two of the empty foil areas n When the same, detect the length L of each active material zone n and the width D of the adjacent empty foil area n When the length L of the active material area is detected n When the preset length II is reached, the width D of the adjacent empty foil area is n When it is greater than 0, the empty foil area adjacent to the active material area is positioned as the tab welding position or glue pasting position.

2. The method for positioning the electrode tabs according to claim 1, characterized in that: The detection device is a detection sensor capable of identifying the boundary between the empty foil area and the active material area, and the detection length is obtained according to the detection time and detection speed output by the detection sensor.

3. The method for positioning the electrode tabs according to claim 1 or 2, characterized in that: The detection device is a reflection sensor.

4. The method for positioning the electrode tabs according to any one of claims 1 to 3, characterized in that: The detection device is arranged in parallel with the electrode plate, and the distance between the two is 0.5mm to 50mm.

5. The method for positioning the electrode tabs according to any one of claims 1 to 4, characterized in that: The empty foil area adjacent to the active material area is the adjacent empty foil area located downstream of the active material area along the winding direction.

6. The method for positioning electrode tabs according to any one of claims 1 to 5, characterized in that: In the method 1, the width D of the plurality of empty foil areas provided on the electrode plate is n Are all different.

7. The method for positioning electrode tabs according to any one of claims 1 to 6, characterized in that: In the second method, the width D of the plurality of empty foil areas provided on the electrode plate is n are the same and the length L of the active material zone n Are all different.

8. The method for positioning electrode tabs according to any one of claims 1 to 7, characterized in that: Among the plurality of active material areas and the plurality of empty foil areas alternately arranged on the electrode plate, the width D of a portion of the empty foil areas n The width D of the empty foil area is the same as the remaining number. n are different, and the length L of at least two of the active material zones n Not the same.

9. The method for positioning electrode tabs according to any one of claims 1 to 8, characterized in that: The number of the empty foil areas arranged on the electrode piece is 3 to 8, and the width D of the empty foil area is n 6~20mm.

10. The method for positioning multiple tabs of an electrode sheet according to any one of claims 1 to 9, characterized in that: The number of the pole lugs is 3 to 5; the number of the pole lugs is less than or equal to the number of the empty foil areas; and the width of the pole lugs is 3 to 6 mm.

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