Detection system and method for pole piece extension area

Abstract

The invention discloses a detection system and method for a pole piece extending area, the system comprises a winding device, a first traction device, a second traction device, a data acquisition device and a processing device, the traction device is used for driving a positive pole piece and a negative pole piece to be wound into the winding device, the negative pole piece comprises an extending area, and the extending area is located in the width direction of the negative pole piece and is used for detecting the extending area of the negative pole piece. The negative pole piece exceeds the area of the positive pole piece; the data acquisition device is used for acquiring a first position corresponding to an edge area of the positive pole piece, a second position corresponding to an edge area of the negative pole piece, a third position corresponding to a positive pole lug on the positive pole piece and a fourth position corresponding to a negative pole lug on the negative pole piece; the processing device is used for processing the first position, the second position, the third position, the fourth position, a first center coordinate of the first traction device relative to the center point of the winding device and a second center coordinate of the second traction device relative to the center point of the winding device according to the first position, the second position, the third position, the fourth position, the first center coordinate of the first traction device and the second center coordinate of the second traction device. And determining the length of the extending area.

Description

Technical Field

[0001] The embodiments of the present application relate to computer technology, and relate to, but are not limited to, a system and method for detecting a pole piece extension area. Background Art

[0002] Lithium batteries are closely related to people's lives and play an irreplaceable role in production and life fields such as communications, automobiles, medical care, home furnishings, and security.

[0003] Winding is an extremely important part of the mid-stage process of lithium batteries. In the current design of lithium batteries with a wound structure, the negative electrode sheet must have an area margin in both width and length directions compared to the positive electrode sheet. Overhang (i.e., the extended area) can refer to the part of the negative electrode sheet that exceeds the positive electrode sheet. For example, it can be the part of the negative electrode sheet that exceeds the positive electrode sheet in the length direction. However, since there is a diaphragm between the negative electrode sheet and the positive electrode sheet, the part of the negative electrode sheet that exceeds the positive electrode sheet cannot be directly measured, which brings inconvenience to the measurement of this parameter.

[0004] Therefore, it is very important to provide a more convenient method to measure the electrode extension area, that is, the part of the negative electrode beyond the positive electrode. Summary of the Invention

[0005] In view of this, the detection system and method of the electrode extension area provided in the embodiment of the present application can quickly calculate the length of the extension area of the negative electrode electrode, improve detection efficiency, and avoid waste of manual resources. The detection system and method of the electrode extension area provided in the embodiment of the present application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a pole piece detection system, the system comprising a winding device, a first traction device, a second traction device, a data acquisition device, and a processing device, wherein the first traction device and the second traction device are respectively connected to the winding device, wherein:

[0007] The first traction device is used to drive the positive electrode sheet to be wound into the winding device;

[0008] The second traction device is used to drive the negative electrode sheet to be wound into the winding device, the negative electrode sheet includes an extension area, and the extension area is an area extending along the length direction of the negative electrode sheet and exceeding the positive electrode sheet;

[0009] The data acquisition device is used to acquire data corresponding to a first position of an edge region of the positive electrode sheet, a second position of an edge region of the negative electrode sheet, a third position of a positive electrode tab on the positive electrode sheet, and a fourth position of a negative electrode tab on the negative electrode sheet;

[0010] The processing device is used to determine the length of the extended area based on the first position, the second position, the third position, the fourth position, the first center coordinate of the first traction device relative to the center point of the winding device, and the second center coordinate of the second traction device relative to the center point of the winding device.

[0011] In some embodiments, the processing device is specifically configured to determine a first position deviation between the positive electrode sheet and the negative electrode sheet based on the third position and the fourth position;

[0012] determining a second positional deviation between the positive electrode sheet and the negative electrode sheet according to the first center coordinate, the second center coordinate, the radius of the roller of the first traction device, the radius of the roller of the second traction device, and the center point of the winding device;

[0013] And, determining a length of the protruding area according to the first position, the second position, the third position, the fourth position, the first position deviation, and the second position deviation.

[0014] In some embodiments, the processing device is further configured to determine a first angle of the first traction device relative to the winding device based on a first distance between a roller of the first traction device and a center point of the winding device, a first tangent line between the roller of the first traction device and the winding device, a center radius of the winding device, a radius of the roller of the first traction device, and the first center coordinate;

[0015] and determining a second angle of the second traction device relative to the winding device based on a second distance between the roller of the second traction device and the center point of the winding device, a second tangent line between the roller of the second traction device and the winding device, a center radius of the winding device, a radius of the roller of the second traction device, and the second center coordinate;

[0016] A second position deviation between the positive electrode sheet and the negative electrode sheet is determined based on the first angle and the second angle.

[0017] In some embodiments, the processing device is further configured to determine a first length from the positive electrode tab to an edge region of the positive electrode sheet based on the first position and the third position, and to determine a second length from the negative electrode tab to an edge region of the negative electrode sheet based on the second position and the fourth position;

[0018] The length of the protruding area is determined according to the first length, the second length, the first position deviation, and the second position deviation.

[0019] In some embodiments, the data acquisition device includes a plurality of data acquisition devices, and the data acquisition devices are respectively arranged on the outside of the first traction device and the outside of the second traction device.

[0020] In some embodiments, there is one data acquisition device, and the data acquisition device is arranged outside the winding device.

[0021] In a second aspect, an embodiment of the present application provides a method for detecting a pole piece extension area, which is applied to a detection system for a pole piece extension area. The system includes a winding device, a first traction device, a second traction device, a data acquisition device, and a processing device. The first traction device and the second traction device are respectively connected to the winding device. The method includes:

[0022] The positive electrode sheet is driven to be wound into the winding device by the first traction device;

[0023] The negative electrode sheet is driven to be wound into the winding device by the second traction device, wherein the negative electrode sheet includes an extension area, and the extension area is an area extending along the length direction of the negative electrode sheet and exceeding the positive electrode sheet;

[0024] collecting, by the data acquisition device, a first position corresponding to an edge region of the positive electrode sheet, a second position corresponding to an edge region of the negative electrode sheet, a third position corresponding to a positive electrode tab on the positive electrode sheet, and a fourth position corresponding to a negative electrode tab on the negative electrode sheet;

[0025] The processing device determines the length of the extended area based on the first position, the second position, the third position, the fourth position, the first center coordinate of the first traction device relative to the center point of the winding device, and the second center coordinate of the second traction device relative to the center point of the winding device.

[0026] In some embodiments, determining the length of the extended area by the processing device based on the first position, the second position, the third position, the fourth position, a first center coordinate of the first traction device relative to the center point of the winding device, and a second center coordinate of the second traction device relative to the center point of the winding device includes:

[0027] determining a first position deviation between the positive electrode sheet and the negative electrode sheet according to the third position and the fourth position;

[0028] determining a second positional deviation between the positive electrode sheet and the negative electrode sheet according to the first center coordinate, the second center coordinate, the radius of the roller of the first traction device, the radius of the roller of the second traction device, and the center point of the winding device;

[0029] And, determining a length of the protruding area according to the first position, the second position, the third position, the fourth position, the first position deviation, and the second position deviation.

[0030] In some embodiments, determining the second positional deviation between the positive electrode sheet and the negative electrode sheet based on the first center coordinate, the second center coordinate, the radius of the roller of the first traction device, the radius of the roller of the second traction device, and the center point of the winding device includes:

[0031] determining a first angle of the first traction device relative to the winding device based on a first distance between a roller of the first traction device and a center point of the winding device, a first tangent line between the roller of the first traction device and the winding device, a center radius of the winding device, a radius of the roller of the first traction device, and the first center coordinate;

[0032] and determining a second angle of the second traction device relative to the winding device based on a second distance between the roller of the second traction device and the center point of the winding device, a second tangent line between the roller of the second traction device and the winding device, a center radius of the winding device, a radius of the roller of the second traction device, and the second center coordinate;

[0033] A second position deviation between the positive electrode sheet and the negative electrode sheet is determined based on the first angle and the second angle.

[0034] In some embodiments, determining the length of the extended area according to the first position, the second position, the third position, the fourth position, the first position deviation, and the second position deviation includes:

[0035] Determine a first length from the positive electrode tab to an edge region of the positive electrode sheet based on the first position and the third position, and determine a second length from the negative electrode tab to an edge region of the negative electrode sheet based on the second position and the fourth position;

[0036] The length of the protruding area is determined according to the first length, the second length, the first position deviation, and the second position deviation.

[0037] The embodiments of the present application provide a detection system and method for an extension area of a pole piece, wherein a first traction device in the detection system drives the positive pole piece to be wound into a winding device; a second traction device drives the negative pole piece to be wound into the winding device, and the negative pole piece includes an extension area, which is an area extending along the length direction of the negative pole piece and exceeding the positive pole piece; a data acquisition device collects data from a first position corresponding to an edge area of the positive pole piece, a second position corresponding to an edge area of the negative pole piece, a third position corresponding to the positive pole ear on the positive pole piece, and a fourth position corresponding to the negative pole ear on the negative pole piece; a processing device determines the length of the extension area based on the first position, the second position, the third position, the fourth position, the first center coordinate of the first traction device relative to the center point of the winding device, and the second center coordinate of the second traction device relative to the center point of the winding device.

[0038] In this way, in the process of the positive electrode sheet and the negative electrode sheet being wound into the winding device, the relevant positions of the positive electrode sheet and the negative electrode sheet are collected by the data acquisition device, and the processing device is used to jointly calculate the length of the extended area based on the collected relevant positions of the positive electrode sheet and the negative electrode sheet, and the center coordinates of the traction device. It can be seen that in the embodiment of the present application, when determining the length of the extended area of the negative electrode sheet relative to the positive electrode sheet, it can be calculated only using the collected data, and the winding process of the electrode sheet is not affected, and there is no need to disassemble the battery, thereby improving the detection efficiency and avoiding waste of human resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present application and, together with the specification, are used to illustrate the technical solutions of the present application.

[0040] Figure 1 A schematic diagram of the effect of an extension area provided in an embodiment of the present application;

[0041] Figure 2 A structural diagram of a detection system for a pole piece extension area provided in an embodiment of the present application;

[0042] Figure 3 A structural diagram of a configuration method of a data acquisition device provided in an embodiment of the present application;

[0043] Figure 4 A structural diagram of another data acquisition device provided in an embodiment of the present application;

[0044] Figure 5 A schematic diagram showing the effect of position deviation between the positive electrode sheet and the negative electrode sheet provided in an embodiment of the present application;

[0045] Figure 6A schematic diagram showing the calculation effect of the second position deviation between the positive electrode sheet and the negative electrode sheet provided in an embodiment of the present application;

[0046] Figure 7 A schematic diagram of the implementation flow of the method for detecting the pole piece extension area provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the specific technical solutions of the present application will be further described in detail below in conjunction with the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application but are not intended to limit the scope of the present application.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing the embodiments of this application only and are not intended to limit this application.

[0049] In the following description, reference is made to “some embodiments”, which describes a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0050] It should be pointed out that the terms "first\second\third" involved in the embodiments of the present application are used to distinguish similar or different objects, and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged with a specific order or sequence where permitted, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

[0051] In the lithium battery production process, winding is the most core link in the mid-stage battery cell assembly process. The winding process has obvious advantages in battery cell consistency and production costs, and has become the mainstream process in the battery cell assembly process.

[0052] The so-called winding process refers to the production process of rolling matching electrode sheets, separators, and termination tape into battery cells. During the winding process in lithium battery production, the separator serves to separate the positive and negative electrodes of the battery, providing insulation and preventing contact and short circuits.

[0053] During production design, if the negative electrode sheet lacks a location to receive lithium ions, the ions will precipitate on the surface of the negative electrode sheet, forming lithium dendrites, which can then pierce the separator, causing a short circuit within the battery and triggering thermal runaway. Therefore, in the production design of lithium batteries, the negative electrode sheet often needs to be overdesigned to avoid this situation, which includes overhang design.

[0054] Overhang refers to the portion of the negative electrode sheet that extends beyond the positive electrode sheet in length and / or width. In a wound battery, the negative electrode sheet is slightly larger than the positive electrode sheet. Figure 1 A schematic diagram of the effect of the extension area is given. Figure 1 As shown, the negative electrode sheet has an area margin relative to the positive electrode sheet in both the length and width directions. Of course, the negative electrode sheet can also have an area margin relative to the positive electrode sheet only in the length direction, which is not limited here.

[0055] However, for wound cells, the overhang is located at the innermost layer of the cell, making it difficult to measure this parameter. To measure this parameter, workers typically need to unwrap the wound cell and use a measuring tool to measure the length. However, this method requires disassembling the normal cell, which requires additional personnel to operate and wastes manpower. It also requires scrapping the cell, increasing production costs.

[0056] In view of this, the embodiment of the present application provides a detection system for the electrode extension area, such as Figure 2 As shown, the detection system for the pole piece extension area includes a winding device 201 , a first traction device 202 , a second traction device 203 , a data acquisition device 204 and a processing device 205 .

[0057] The first traction device 202 and the second traction device 203 are respectively connected to the winding device 201 .

[0058] The first traction device 202 is used to drive the positive electrode sheet to be wound into the winding device 201.

[0059] The second traction device 203 is used to drive the negative electrode sheet to be wound into the winding device 201. The negative electrode sheet includes an extension area, which is an area extending along the length direction of the negative electrode sheet and exceeding the positive electrode sheet.

[0060] It can be understood that in the winding process of the battery, the negative electrode sheet and the positive electrode sheet are generally fed first, and then put into the winding device for winding. During the winding, the negative electrode sheet and the positive electrode sheet are compressed together.

[0061] Based on this, in the embodiment of the present application, the process of extending the negative electrode sheet and the positive electrode sheet from the traction device can be to first extend the negative electrode sheet from the second traction device and then extend the positive electrode sheet from the first traction device, or to first extend the positive electrode sheet from the first traction device and then extend the negative electrode sheet from the second traction device. The order in which the positive electrode sheet and the negative electrode sheet are extended from the traction device is not limited. In the process of winding the positive electrode sheet and the negative electrode sheet into the winding device, the second traction device can first drive the negative electrode sheet to be wound into the winding device, and then the first traction device can drive the positive electrode sheet to be wound into the winding device. In this way, along the length direction of the negative electrode sheet, the negative electrode sheet may extend beyond a portion of the positive electrode sheet, and there may be a positional deviation between the negative electrode sheet and the positive electrode sheet in the time dimension.

[0062] The data acquisition device 204 is used to collect data at a first position corresponding to the edge area of the positive electrode sheet, a second position corresponding to the edge area of the negative electrode sheet, a third position corresponding to the positive electrode tab on the positive electrode sheet, and a fourth position corresponding to the negative electrode tab on the negative electrode sheet.

[0063] In the embodiment of the present application, there is no limitation on the number and setting position of the data acquisition device 204. For example, in some embodiments, Figure 3 As shown, a setting method of the data acquisition device is given. The data acquisition device 204 may include multiple data acquisition devices, and the data acquisition devices 204 are respectively set on the outside of the first traction device 202 and the outside of the second traction device 203.

[0064] based on Figure 3 In the setting mode of the data acquisition device, when the first traction device 202 drives the positive electrode sheet to be wound into the winding device 201, the data acquisition device 204 set on the outside of the first traction device 202 can obtain the first position corresponding to the edge area of the positive electrode sheet. The first position can be a position coordinate. Based on the position coordinate, the current length of the positive electrode sheet (or the edge length) can be determined, and S P1 express.

[0065] Similarly, when the second traction device 203 drives the negative electrode sheet to be wound into the winding device 201, the data acquisition device 204 arranged outside the second traction device 203 can obtain the second position corresponding to the edge area of the negative electrode sheet. The second position can be a position coordinate. Based on the position coordinate, the current length of the negative electrode sheet (or the edge length) can be determined, and S N1 express.

[0066] During the battery assembly process, the negative electrode tab will be firmly connected to the negative electrode sheet through welding, crimping, etc., and the positive electrode tab will also be connected to the positive electrode sheet to ensure the stability and reliability of current transmission.

[0067] Based on this, when the first traction device 202 continues to drive the positive electrode sheet to be wound into the winding device 201, the data acquisition device 204 arranged on the outside of the second traction device 203 can record the third position corresponding to the positive electrode ear on the positive electrode sheet when the positive electrode ear is detected. The third position can be a position coordinate. Based on the position coordinate, the length of the positive electrode sheet at the moment the positive electrode ear on the positive electrode sheet is detected can be determined, and S P2 express.

[0068] When the second traction device 203 continues to drive the negative electrode sheet to be wound into the winding device 201, the data acquisition device 204 provided on the outer side of the second traction device 203 can record the fourth position corresponding to the negative electrode tab on the negative electrode sheet when the negative electrode tab is detected. The fourth position can be a position coordinate. Based on the position coordinate, the length of the negative electrode sheet at the moment when the negative electrode tab on the negative electrode sheet is detected can be determined, and S N2 express.

[0069] In other embodiments, Figure 4 As shown, another arrangement of the data acquisition device is provided. There is only one data acquisition device 204 , and the data acquisition device 204 can be arranged outside the winding device 201 .

[0070] based on Figure 4 In the setting mode of the data acquisition device, when the first traction device 202 drives the positive electrode sheet to be wound into the winding device 201, the data acquisition device 204 set outside the winding device 201 can obtain the first position corresponding to the edge area of the positive electrode sheet. The first position can be a position coordinate. Based on the position coordinate, the current length of the positive electrode sheet (or the edge length) can be determined. P1 express.

[0071] Similarly, when the second traction device 203 drives the negative electrode sheet to be wound into the winding device 201, the data acquisition device 204 disposed outside the winding device 201 can obtain the second position corresponding to the edge area of the negative electrode sheet. The second position can be a position coordinate. Based on the position coordinate, the current length of the negative electrode sheet (or the edge length) can be determined, and S N1 express.

[0072] As an example, the first and second positions collected during the process of winding the positive and negative electrode sheets into the winding device 201 may also be length information recorded by a range encoder. For example, the length information may be represented by the encoder's rotation speed or rotation duration, and the manner in which the range encoder records the length information is not limited herein. Of course, the first and second positions may also be represented by other parameters, which are not listed here.

[0073] During the battery assembly process, the negative electrode tab will be firmly connected to the negative electrode sheet through welding, crimping, etc., and the positive electrode tab will also be connected to the positive electrode sheet to ensure the stability and reliability of current transmission.

[0074] Based on this, when the first traction device 202 continues to drive the positive electrode sheet to be wound into the winding device 201, the data acquisition device 204 can record the third position corresponding to the positive electrode ear on the positive electrode sheet when the positive electrode ear is detected. The third position can be a position coordinate. Based on the position coordinate, the length of the positive electrode sheet at the moment the positive electrode ear is detected can be determined, and S P2 express.

[0075] When the second traction device 203 continues to drive the negative electrode sheet to be wound into the winding device 201, the data acquisition device 204 can record the fourth position corresponding to the negative electrode tab on the negative electrode sheet when the negative electrode tab is detected. The fourth position can be a position coordinate. Based on the position coordinate, the length of the positive electrode sheet at the moment the positive electrode tab is detected can be determined, and S N2 express.

[0076] Among them, the third position and the fourth position can be position coordinates or length information, which are similar to the first position and the second position mentioned above and will not be repeated here.

[0077] The processing device 205 is used to determine the length of the extension area based on the first position, the second position, the third position, the fourth position, the first center coordinate of the first traction device 202 relative to the center point of the winding device 201, and the second center coordinate of the second traction device 203 relative to the center point of the winding device 201.

[0078] In the embodiments of the present application, there is no limitation on the shapes of the first traction device and the second traction device and the components included. For example, in some embodiments, in order to ensure that the pole piece can move forward smoothly and continuously during the winding process, reduce the friction and wear between the pole piece and the traction device, and ensure that the pole piece can be wound into a specific shape (such as a cylinder or a square), Figure 3 or Figure 4 As shown, the first traction device 202 and the second traction device 203 can be set to include a stick, and the pole piece is driven to be wound by the roller. Of course, the first traction device 202 and the second traction device 203 can also include other components, for example, a power component, which drives the roller to rotate, which will not be explained one by one here.

[0079] Thus, in some embodiments, the first traction device 202 and the second traction device 203 both include rollers. The radius of the rollers included in the first traction device 202 and the second traction device 203 can be the same or different, and this is not limited in the embodiments of the present application. For ease of explanation, the following example uses the case where the rollers included in the first traction device 202 and the second traction device 203 have the same radius, and both can be represented by r.

[0080] Based on this, in some embodiments, the processing device 205 may specifically perform the following method to determine the length of the extended area of the negative electrode plate relative to the positive electrode plate:

[0081] First, if Figure 5 As shown, from the above analysis, it can be seen that there is a position deviation between the positive electrode plate and the negative electrode plate in both the time dimension and the space dimension. Based on this, the processing device 205 can first calculate the position deviation between the positive electrode plate and the negative electrode plate in the time dimension and the space dimension.

[0082] In some embodiments, the processing device 205 may be configured to determine the third position S corresponding to the positive electrode tab on the positive electrode sheet. P2 The fourth position S corresponding to the negative electrode tab on the negative electrode sheet N2 , determine the first position deviation between the positive electrode sheet and the negative electrode sheet, the first position deviation can be used t It means that the first position deviation is the deviation between the positive electrode plate and the negative electrode plate in the time dimension.

[0083] In a specific embodiment, the first position deviation E between the positive electrode sheet and the negative electrode sheet is t =S P2 -S N2 .

[0084] Furthermore, in some embodiments, the processing device 205 may calculate the rotation speed of the first traction device 202 according to the first center coordinate (X1, Y1) and the second center coordinate (X2, Y2) of the head position of the first traction device 202 away from the center point of the winding device 201, the radius r of the rollers of the first traction device 202 and the second traction device 203, and the center point (X N ,Y N ), determine the second position deviation between the positive electrode piece and the negative electrode piece, the second position deviation can be used p It means that the second position deviation is the deviation between the positive electrode plate and the negative electrode plate in the spatial dimension.

[0085] In some embodiments, the processing device 205 calculates the second position deviation between the positive electrode piece and the negative electrode piece, such as Figure 6 As shown, the following methods can be executed:

[0086] First, taking the first traction device 202 as an example, the processing device 205 can determine the first angle a of the first traction device 202 relative to the winding device 201 based on the first distance L between the center points of the first traction device 202 and the winding device 201, the first tangent M between the roller of the first traction device 202 and the winding device 201 (the tangent point on the winding device is K, and the tangent point on the roller of the first traction device is Q), the center radius R of the winding device 201 (the center point is O), the radius r of the roller of the first traction device 201 (the center point of the roller of the first traction device is N) and the first center coordinates (X1, Y1). N .

[0087] Specifically, if Figure 6 As shown, the first center coordinate of the first traction device 202 can be used as the origin, and a perpendicular line M1 relative to the center radius R of the winding device 201 can be drawn with the perpendicular point S. The resulting quadrilateral SKQN is a rectangle, and the perpendicular line M1 has the same length as the first tangent line M.

[0088] Based on this,

[0089] Furthermore, according to the length of M1, L and (Rr), the first angle a can be calculated. N .

[0090] Similarly, for the second traction device 203, the processing device 205 can determine the second angle a of the second traction device 203 relative to the winding device 201 based on the second distance between the second traction device 203 and the center point of the winding device 201, the second tangent between the roller of the second traction device 203 and the winding device 201, the center radius R of the winding device 201, the radius r of the roller of the second traction device 203 and the second center coordinate (X2, Y2). p .

[0091] Here, the method for calculating the second angle is the same as the method for calculating the first angle, and will not be repeated here.

[0092] Based on the first angle and the second angle obtained by the above calculation, the processing device 205 can determine the second position deviation between the positive electrode sheet and the negative electrode sheet according to the first angle and the second angle.

[0093] In a specific embodiment, the second position deviation between the positive electrode sheet and the negative electrode sheet can be expressed as E p Indicates that the second deviation position E p =a*r(Formula 2);

[0094] Where a is the first angle a N and the second angle a p The harmony.

[0095] In some embodiments, the processing device determines the first position deviation E between the positive electrode sheet and the negative electrode sheet. t and the second position deviation E p Thereafter, the length of the extended area may be determined according to the first position, the second position, the third position, the fourth position, the first position deviation, and the second position deviation.

[0096] In some embodiments, the processing device 205 is specifically used to determine a first length from the positive electrode tab to the edge area of the positive electrode sheet based on the first position and the third position, and to determine a second length from the negative electrode tab to the edge area of the negative electrode sheet based on the second position and the fourth position.

[0097] In a specific embodiment, the first length from the positive electrode tab to the edge of the positive electrode tab can be expressed as S p Indicates that the first length can be determined by the difference between the third position corresponding to the positive electrode tab on the positive electrode sheet and the first position corresponding to the edge area of the positive electrode sheet, that is, S p =S P2 -S P1 .

[0098] Similarly, the second length of the edge region from the negative electrode tab to the negative electrode tab can be expressed as S N Indicates that the second length can be determined by the difference between the fourth position corresponding to the negative electrode tab on the negative electrode sheet and the second position corresponding to the edge area of the negative electrode sheet, that is, S N =S N2 -S N1 .

[0099] After calculating the first length of the edge area from the positive electrode sheet to the positive electrode tab and the second length of the edge area from the negative electrode sheet to the negative electrode tab, the length of the extended area can be determined based on the first length, the second length, the first position deviation and the second position deviation.

[0100] In a specific embodiment, the length of the overhang area Overhang=S N +ES p .

[0101] By implementing the above embodiment, when determining the length of the protruding area of the negative electrode sheet relative to the positive electrode sheet, it can be calculated only using the collected data, while the winding process of the electrode sheet is not affected and there is no need to disassemble the battery, thereby improving detection efficiency and avoiding waste of human resources.

[0102] Figure 7 Schematic diagram of the implementation process of the detection method of the electrode extension area provided in the embodiment of the present application. Figure 7 As shown, the method may include the following steps 701 to 703:

[0103] In step 701, the positive electrode sheet is driven into the winding device by a first traction device; the negative electrode sheet is driven into the winding device by a second traction device, and the negative electrode sheet includes an extension area, which is an area extending along the length direction of the negative electrode sheet and exceeding the positive electrode sheet.

[0104] The detection method of the pole piece extension area provided in the embodiment of the present application is applied to the pole piece detection system, which includes a winding device, a first traction device, a second traction device, a data acquisition device and a processing device, and the first traction device and the second traction device are respectively connected to the winding device.

[0105] It can be understood that in the winding process of the battery, the negative electrode sheet and the positive electrode sheet are generally fed first, and then put into the winding device for winding. During the winding, the negative electrode sheet and the positive electrode sheet are compressed together.

[0106] Based on this, in an embodiment of the present application, in the process of winding the positive electrode sheet and the negative electrode sheet into the winding device, the negative electrode sheet can be first driven into the winding device by the second traction device, and then the positive electrode sheet can be driven into the winding device by the first traction device. In this way, along the length direction of the negative electrode sheet, the negative electrode sheet may exceed part of the positive electrode sheet, and there is a position deviation between the negative electrode sheet and the positive electrode sheet in the time dimension.

[0107] Step 702 : Data is collected by a data collection device at a first position corresponding to an edge region of the positive electrode sheet, a second position corresponding to an edge region of the negative electrode sheet, a third position corresponding to a positive electrode tab on the positive electrode sheet, and a fourth position corresponding to a negative electrode tab on the negative electrode sheet.

[0108] In the embodiments of the present application, there is no limitation on the number and setting position of the data acquisition device. Figure 3 As shown, a setting method of a data acquisition device is given. The data acquisition device may include multiple data acquisition devices, and the data acquisition devices are respectively set on the outside of the first traction device and the outside of the second traction device.

[0109] based on Figure 3 In the setting mode of the data acquisition device, when the first traction device drives the positive electrode sheet to be wound into the winding device, the data acquisition device arranged outside the first traction device can obtain the first position corresponding to the edge area of the positive electrode sheet. The first position can be a position coordinate. Based on the position coordinate, the current length of the positive electrode sheet (or the edge length) can be determined, and S P1 express.

[0110] Similarly, when the second traction device drives the negative electrode sheet to be wound into the winding device, the data acquisition device arranged on the outside of the second traction device can obtain the second position corresponding to the edge area of the negative electrode sheet. The second position can be a position coordinate. Based on the position coordinate, the current length of the negative electrode sheet (or the edge length) can be determined, and S N1 express.

[0111] During the battery assembly process, the negative electrode tab will be firmly connected to the negative electrode sheet through welding, crimping, etc., and the positive electrode tab will also be connected to the positive electrode sheet to ensure the stability and reliability of current transmission.

[0112] Based on this, when the first traction device continues to drive the positive electrode sheet to be wound into the winding device, the data acquisition device arranged on the outside of the first traction device can record the third position corresponding to the positive electrode ear on the positive electrode sheet when the positive electrode ear is detected. The third position can be a position coordinate. Based on the position coordinate, the length of the positive electrode sheet at the moment the positive electrode ear on the positive electrode sheet is detected can be determined, and S P2 express.

[0113] In the process that the second traction device continues to drive the negative electrode sheet to be wound into the winding device, the data acquisition device arranged on the outside of the second traction device can record the fourth position corresponding to the negative electrode tab on the negative electrode sheet when the negative electrode tab is detected. The fourth position can be a position coordinate. Based on the position coordinate, the length of the negative electrode sheet at the moment when the negative electrode tab on the negative electrode sheet is detected can be determined, and S N2 express.

[0114] In other embodiments, Figure 4 As shown, another arrangement of the data acquisition device is given, where there is only one data acquisition device, and the data acquisition device can be arranged outside the winding device.

[0115] based on Figure 4 In the setting mode of the data acquisition device, when the first traction device drives the positive electrode sheet to be wound into the winding device, the data acquisition device arranged outside the winding device can obtain the first position corresponding to the edge area of the positive electrode sheet. The first position can be a position coordinate. Based on the position coordinate, the current length of the positive electrode sheet (or the edge length) can be determined, and S P1 express.

[0116] Similarly, when the second traction device drives the negative electrode sheet to be wound into the winding device, the data acquisition device arranged outside the winding device can obtain the second position corresponding to the edge area of the negative electrode sheet. The second position can be a position coordinate. Based on the position coordinate, the current length of the negative electrode sheet (or the edge length) can be determined, and S N1 express.

[0117] During the battery assembly process, the negative electrode tab will be firmly connected to the negative electrode sheet through welding, crimping, etc., and the positive electrode tab will also be connected to the positive electrode sheet to ensure the stability and reliability of current transmission.

[0118] Based on this, when the first traction device continues to drive the positive electrode sheet to be wound into the winding device, the data acquisition device can record the third position corresponding to the positive electrode ear on the positive electrode sheet when the positive electrode ear is detected. The third position can be a position coordinate. Based on the position coordinate, the length of the positive electrode sheet at the moment the positive electrode ear is detected can be determined, and S P2 express.

[0119] When the second traction device continues to drive the negative electrode sheet to be wound into the winding device, the data acquisition device can record the fourth position corresponding to the negative electrode ear on the negative electrode sheet when the negative electrode ear is detected. The fourth position can be a position coordinate. Based on the position coordinate, the length of the positive electrode sheet at the moment the positive electrode ear is detected can be determined, and S N2 express.

[0120] Step 703: The processing device determines the length of the extension area based on the first position, the second position, the third position, the fourth position, the first center coordinate of the first traction device relative to the center point of the winding device, and the second center coordinate of the second traction device relative to the center point of the winding device.

[0121] In the embodiments of the present application, there is no limitation on the shapes of the first traction device and the second traction device. For example, in some embodiments, in order to ensure that the pole piece can move forward smoothly and continuously during the winding process, reduce the friction and wear between the pole piece and the traction device, and ensure that the pole piece can be wound into a specific shape (such as a cylinder or a square), Figure 3 or Figure 4 As shown, it can be provided that both the first traction device and the second traction device include a stick.

[0122] Thus, in some embodiments, the rollers of the first traction device and the second traction device are both cylinders, and the radius of the roller of the first traction device and the radius of the roller of the second traction device may be the same or different. In the embodiment of the present application, the radius of the roller of the first traction device and the roller of the second traction device are the same as an example, and they can both be represented by r.

[0123] Based on this, in some embodiments, the processing device may specifically perform the following method to determine the length of the extended area of the negative electrode plate relative to the positive electrode plate:

[0124] First, if Figure 5As shown, from the above analysis, it can be seen that there is a position deviation between the positive electrode plate and the negative electrode plate in both the time dimension and the space dimension. Based on this, the processing device can first calculate the position deviation between the positive electrode plate and the negative electrode plate in the time dimension and the space dimension.

[0125] In some embodiments, the processing device may be configured to determine the third position S corresponding to the positive electrode tab on the positive electrode sheet. P2 The fourth position S corresponding to the negative electrode tab on the negative electrode sheet N2 , determine the first position deviation between the positive electrode sheet and the negative electrode sheet, the first position deviation can be used t It means that the first position deviation is the deviation between the positive electrode plate and the negative electrode plate in the time dimension.

[0126] In a specific embodiment, the first position deviation E between the positive electrode sheet and the negative electrode sheet is t =S P2 -S N2 .

[0127] Furthermore, in some embodiments, the processing device may calculate the center coordinates (X1, Y1) and the second center coordinates (X2, Y2) of the first traction device relative to the center of the winding device, the radius r of the rollers of the first traction device and the second traction device, and the center of the winding device (X N ,Y N ), determine the second position deviation between the positive electrode piece and the negative electrode piece, the second position deviation can be used p It means that the second position deviation is the deviation between the positive electrode plate and the negative electrode plate in the spatial dimension.

[0128] In some embodiments, the processing device calculates the second position deviation between the positive electrode piece and the negative electrode piece, such as Figure 6 As shown, the following methods can be executed:

[0129] First, taking the first traction device as an example, the processing device can determine the first angle a of the first traction device relative to the winding device based on the first distance L between the first traction device 202 and the center point of the winding device, the first tangent M between the roller of the first traction device and the winding device (the tangent point on the winding device is K, and the tangent point at the head position of the first traction device is Q), the center radius R of the winding device (the center point is O), the radius r of the roller of the first traction device (the center point of the head position of the first traction device is N) and the first center coordinates (X1, Y1). N .

[0130] Specifically, if Figure 6As shown, the first center coordinate of the first traction device can be used as the origin, and a perpendicular line M1 relative to the center radius R of the winding device can be drawn, with the perpendicular point being S. The formed quadrilateral SKQN is a rectangle, and the perpendicular line M1 has the same length as the first tangent line M.

[0131] Based on this,

[0132] Furthermore, according to the length of M1, L and (Rr), the first angle a can be calculated. N .

[0133] Similarly, for the second traction device, the processing device can determine the second angle a of the second traction device relative to the winding device based on the second distance between the center point of the second traction device and the winding device, the second tangent between the roller of the second traction device and the winding device, the center radius R of the winding device, the radius r of the roller of the second traction device and the second center coordinate (X2, Y2) p .

[0134] Here, the method for calculating the second angle is the same as the method for calculating the first angle, and will not be repeated here.

[0135] Based on the first angle and the second angle obtained by the above calculation, the processing device can determine the second position deviation between the positive electrode sheet and the negative electrode sheet according to the first angle and the second angle.

[0136] In a specific embodiment, the second position deviation between the positive electrode sheet and the negative electrode sheet can be expressed as E p Indicates that the second deviation position E p =a*r(Formula 2);

[0137] Where a is the first angle a N and the second angle a p The harmony.

[0138] In some embodiments, the processing device determines the first position deviation E between the positive electrode sheet and the negative electrode sheet. t and the second position deviation E p Thereafter, the length of the extended area may be determined according to the first position, the second position, the third position, the fourth position, the first position deviation, and the second position deviation.

[0139] In some embodiments, the processing device is specifically used to determine a first length from the positive electrode tab to the edge area of the positive electrode sheet based on the first position and the third position, and to determine a second length from the negative electrode tab to the edge area of the negative electrode sheet based on the second position and the fourth position.

[0140] In a specific embodiment, the first length from the positive electrode tab to the edge of the positive electrode tab can be expressed as Sp Indicates that the first length can be determined by the difference between the third position corresponding to the positive electrode tab on the positive electrode sheet and the first position corresponding to the edge area of the positive electrode sheet, that is, S p =S P2 -S P1 .

[0141] Similarly, the second length of the edge region from the negative electrode tab to the negative electrode tab can be expressed as S N Indicates that the second length can be determined by the difference between the fourth position corresponding to the negative electrode tab on the negative electrode sheet and the second position corresponding to the edge area of the negative electrode sheet, that is, S N =S N2 -S N1 .

[0142] After calculating the first length of the edge area from the positive electrode sheet to the positive electrode tab and the second length of the edge area from the negative electrode sheet to the negative electrode tab, the length of the extended area can be determined based on the first length, the second length, the first position deviation and the second position deviation.

[0143] In a specific embodiment, the length of the overhang area Overhang=S N +ES p .

[0144] In an embodiment of the present application, during the process of the positive electrode sheet and the negative electrode sheet being wound into the winding device, the relevant positions of the positive electrode sheet and the negative electrode sheet are collected by a data acquisition device, and the processing device is used to jointly calculate the length of the extended area based on the collected relevant positions of the positive electrode sheet and the negative electrode sheet, and the center coordinates of the roller of the traction device. It can be seen that in an embodiment of the present application, when determining the length of the extended area of the negative electrode sheet relative to the positive electrode sheet, it can be calculated only using the collected data, and the winding process of the electrode sheet is not affected, and there is no need to disassemble the battery, thereby improving the detection efficiency and avoiding waste of human resources.

[0145] It should be understood that, although the steps in the above-mentioned flowcharts are shown in sequence according to the instructions of the arrows, these steps are not necessarily performed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the above-mentioned flowcharts may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0146] It should be noted that, in the embodiment of the present application, if the above method is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the relevant technology can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling an electronic device to execute all or part of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a U disk, a mobile hard disk, a read-only memory (ROM), a magnetic disk or an optical disk. In this way, the embodiment of the present application is not limited to any specific combination of hardware and software.

[0147] It should be understood that "one embodiment" or "an embodiment" or "some embodiments" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in one embodiment" or "in an embodiment" or "in some embodiments" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application. The above-mentioned serial numbers of the embodiments of the present application are for description only and do not represent the advantages and disadvantages of the embodiments. The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced to each other. For the sake of brevity, they will not be repeated here.

[0148] The term "and / or" in this article is only a description of the association relationship between associated objects, indicating that there can be three relationships. For example, object A and / or object B can mean: object A exists alone, object A and object B exist at the same time, and object B exists alone.

[0149] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0150] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The embodiments described above are merely illustrative. For example, the division of the modules is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple modules or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or modules can be electrical, mechanical or other forms.

[0151] The modules described above as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules; they may be located in one place or distributed across multiple network units; some or all of the modules may be selected according to actual needs to achieve the purpose of this embodiment.

[0152] In addition, all functional modules in the embodiments of the present application can be integrated into one processing unit, or each module can be a separate unit, or two or more modules can be integrated into one unit; the above-mentioned integrated modules can be implemented in the form of hardware or in the form of hardware plus software functional units.

[0153] Those skilled in the art will understand that all or part of the steps of implementing the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM), magnetic disks or optical disks, and other media that can store program codes.

[0154] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application, or the part that contributes to the relevant technology, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling an electronic device to execute all or part of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROMs, magnetic disks or optical disks.

[0155] The methods disclosed in the several method embodiments provided in this application can be arbitrarily combined without conflict to obtain new method embodiments.

[0156] The features disclosed in the several product embodiments provided in this application can be arbitrarily combined without conflict to obtain new product embodiments.

[0157] The features disclosed in the several method or device embodiments provided in this application can be arbitrarily combined without conflict to obtain new method embodiments or device embodiments.

[0158] The above is merely an embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A detection system for a pole piece extension area, characterized in that: The system includes a winding device, a first traction device, a second traction device, a data acquisition device and a processing device, wherein the first traction device and the second traction device are respectively connected to the winding device, wherein: The first traction device is used to drive the positive electrode sheet to be wound into the winding device; The second traction device is used to drive the negative electrode sheet to be wound into the winding device, the negative electrode sheet includes an extension area, and the extension area is an area extending along the length direction of the negative electrode sheet and exceeding the positive electrode sheet; The data acquisition device is used to acquire data corresponding to a first position of an edge region of the positive electrode sheet, a second position of an edge region of the negative electrode sheet, a third position of a positive electrode tab on the positive electrode sheet, and a fourth position of a negative electrode tab on the negative electrode sheet; The processing device is used to determine the length of the extended area based on the first position, the second position, the third position, the fourth position, the first center coordinate of the first traction device relative to the center point of the winding device, and the second center coordinate of the second traction device relative to the center point of the winding device.

2. The system according to claim 1, wherein: The first traction device and the second traction device both include rollers, and the processing device is specifically used to: determining a first position deviation between the positive electrode sheet and the negative electrode sheet according to the third position and the fourth position; determining a second positional deviation between the positive electrode sheet and the negative electrode sheet according to the first center coordinate, the second center coordinate, the radius of the roller of the first traction device, the radius of the roller of the second traction device, and the center point of the winding device; And, determining a length of the protruding area according to the first position, the second position, the third position, the fourth position, the first position deviation, and the second position deviation.

3. The system according to claim 2, characterized in that The processing device is specifically used for: determining a first angle of the first traction device relative to the winding device based on a first distance between a roller of the first traction device and a center point of the winding device, a first tangent line between the roller of the first traction device and the winding device, a center radius of the winding device, a radius of the roller of the first traction device, and the first center coordinate; and determining a second angle of the second traction device relative to the winding device based on a second distance between the roller of the second traction device and the center point of the winding device, a second tangent line between the roller of the second traction device and the winding device, a center radius of the winding device, a radius of the roller of the second traction device, and the second center coordinate; A second position deviation between the positive electrode sheet and the negative electrode sheet is determined based on the first angle and the second angle.

4. The system according to claim 2 or 3, characterized in that The processing device is specifically used for: Determine a first length from the positive electrode tab to an edge region of the positive electrode sheet based on the first position and the third position, and determine a second length from the negative electrode tab to an edge region of the negative electrode sheet based on the second position and the fourth position; The length of the protruding area is determined according to the first length, the second length, the first position deviation, and the second position deviation.

5. The system according to claim 1, wherein: The data acquisition device includes a plurality of data acquisition devices, and the data acquisition devices are respectively arranged on the outside of the first traction device and the outside of the second traction device.

6. The system according to claim 1, wherein: There is one data acquisition device, and the data acquisition device is arranged outside the winding device.

7. A method for detecting a pole piece extension area, characterized in that: A detection system for a pole piece extension area, the system comprising a winding device, a first traction device, a second traction device, a data acquisition device, and a processing device, wherein the first traction device and the second traction device are respectively connected to the winding device, and the method comprises: The positive electrode sheet is driven to be wound into the winding device by the first traction device; The negative electrode sheet is driven to be wound into the winding device by the second traction device, wherein the negative electrode sheet includes an extension area, and the extension area is an area extending along the length direction of the negative electrode sheet and exceeding the positive electrode sheet; collecting, by the data acquisition device, a first position corresponding to an edge region of the positive electrode sheet, a second position corresponding to an edge region of the negative electrode sheet, a third position corresponding to a positive electrode tab on the positive electrode sheet, and a fourth position corresponding to a negative electrode tab on the negative electrode sheet; The processing device determines the length of the extended area based on the first position, the second position, the third position, the fourth position, the first center coordinate of the first traction device relative to the center point of the winding device, and the second center coordinate of the second traction device relative to the center point of the winding device.

8. The method according to claim 7, characterized in that The determining, by the processing device, the length of the extended area based on the first position, the second position, the third position, the fourth position, a first center coordinate of the first traction device relative to the center point of the winding device, and a second center coordinate of the second traction device relative to the center point of the winding device, comprises: determining a first position deviation between the positive electrode sheet and the negative electrode sheet according to the third position and the fourth position; determining a second positional deviation between the positive electrode sheet and the negative electrode sheet according to the first center coordinate, the second center coordinate, the radius of the roller of the first traction device, the radius of the roller of the second traction device, and the center point of the winding device; And, determining a length of the protruding area according to the first position, the second position, the third position, the fourth position, the first position deviation, and the second position deviation.

9. The method according to claim 8, characterized in that The determining, based on the first center coordinate, the second center coordinate, the radius of the roller of the first traction device, the radius of the roller of the second traction device, and the center point of the winding device, a second position deviation between the positive electrode sheet and the negative electrode sheet includes: determining a first angle of the first traction device relative to the winding device based on a first distance between a roller of the first traction device and a center point of the winding device, a first tangent line between the roller of the first traction device and the winding device, a center radius of the winding device, a radius of the roller of the first traction device, and the first center coordinate; and determining a second angle of the second traction device relative to the winding device based on a second distance between the roller of the second traction device and the center point of the winding device, a second tangent line between the roller of the second traction device and the winding device, a center radius of the winding device, a radius of the roller of the second traction device, and the second center coordinate; A second position deviation between the positive electrode sheet and the negative electrode sheet is determined based on the first angle and the second angle.

10. The method according to claim 8 or 9, characterized in that The determining the length of the extended area according to the first position, the second position, the third position, the fourth position, the first position deviation, and the second position deviation includes: Determine a first length from the positive electrode tab to an edge region of the positive electrode sheet based on the first position and the third position, and determine a second length from the negative electrode tab to an edge region of the negative electrode sheet based on the second position and the fourth position; The length of the protruding area is determined according to the first length, the second length, the first position deviation, and the second position deviation.

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