Pole cutting method and control system

Abstract

The present application provides a pole piece cutting method and control system, which relates to the field of battery technology. The pole piece cutting method includes: obtaining the offset distance between the detection reference and the cutting position of the pole piece; obtaining the actual distance between the cutting position and the cutting device based on the offset distance and the distance between the detection reference and the cutting device; obtaining the cutting timing of the cutting position to be transported to the cutting device based on the actual distance, so that the cutting device cuts the cutting position. By obtaining the offset distance between the detection reference and the cutting position of the pole piece, it is equivalent to obtaining the deviation from the detection reference caused during the transmission of the pole piece; thereby, the actual position of the cutting position can be obtained, so as to obtain the accurate timing of the cutting position to be transported to the cutting device, so that the cutting device can accurately cut at the cutting position, improve the cutting accuracy, and thus help improve the cutting and forming quality of the pole piece and the reliability and safety of the battery using the pole piece.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a pole piece cutting method and control system. Background Art

[0002] Lithium batteries are widely used in electronics, vehicles, aerospace, and other fields. As the application environment and conditions become increasingly complex, higher requirements are placed on battery safety, energy density, and production costs.

[0003] During the battery production process, the electrode sheets need to be cut so that the length of the electrode sheets meets the requirements. The quality of the electrode sheet cutting has a great impact on the battery's safety performance, energy sealing and production costs. Therefore, how to improve the cutting quality of the electrode sheets has become an urgent problem to be solved in the battery manufacturing process. Summary of the Invention

[0004] The embodiments of the present application provide a pole piece cutting method and control system to improve the problem of poor pole piece cutting quality.

[0005] In a first aspect, an embodiment of the present application provides a pole piece cutting method, comprising:

[0006] Obtaining the offset distance between the detection reference and the cutting position of the pole piece;

[0007] Obtaining an actual distance between the cutting position and the cutting device according to the offset distance and the distance between the detection reference and the cutting device;

[0008] The cutting timing when the cutting position is transported to the cutting device is acquired according to the actual distance, and the cutting device is controlled to cut the cutting position according to the cutting timing.

[0009] In the above technical solution, by obtaining the offset distance between the detection reference and the cutting position of the electrode, it is equivalent to obtaining the deviation from the detection reference caused by the manufacturing error, installation error and other reasons of the conveying equipment during the transmission of the electrode; then the actual distance between the cutting position and the cutting equipment is obtained based on the offset distance and the distance between the detection reference and the cutting equipment, which is equivalent to obtaining the actual position of the cutting position, so as to obtain the accurate cutting time when the cutting position is transported to the cutting equipment, so that the cutting position can be accurately positioned at the cutting equipment, so that the cutting equipment can accurately cut at the cutting position, thereby improving the cutting accuracy, which is beneficial to improving the cutting and forming quality of the electrode and the reliability and safety of the battery using the electrode.

[0010] In some embodiments of the first aspect of the present application, obtaining the offset distance between the detection reference and the cutting position of the pole piece includes:

[0011] The cutting position and the detection reference are photographed by a photographing device to obtain the offset distance between the detection reference of the photographing device and the cutting position.

[0012] In the above technical solution, the cutting position and the detection reference are photographed by a photographing device to obtain the detection reference of the photographing device and the offset distance of the cutting position. The acquisition method is simple and convenient, which can improve the efficiency of obtaining the offset distance, thereby improving the efficiency of pole piece cutting and facilitating continuous pole piece cutting.

[0013] In some embodiments of the first aspect of the present application, the pole piece cutting method further includes:

[0014] Obtaining the initial position of the cutting position;

[0015] According to the distance between the initial position and the detection reference, the shooting timing of the shooting device to shoot the cutting position and the detection reference is obtained, and according to the shooting timing, the shooting device is controlled to shoot the cutting position and the detection reference.

[0016] In the above technical solution, based on the distance between the initial position and the detection reference, the shooting timing of the cutting position when it is transported to the shooting device to shoot the cutting position and the detection reference is obtained, and the shooting device is controlled to shoot the cutting position and the detection reference according to the shooting timing, so that the shooting device can accurately shoot the cutting position and the detection reference, which is conducive to obtaining the accurate offset distance between the detection reference and the cutting position.

[0017] In some embodiments of the first aspect of the present application, obtaining the initial position of the cutting position includes:

[0018] Whether the cutting position reaches the initial position is detected by an optical fiber sensor.

[0019] In the above technical solution, the optical fiber sensor is used to detect whether the cutting position reaches the initial position. The acquisition method is simple and convenient, which can improve the acquisition efficiency, improve the electrode cutting efficiency and facilitate continuous electrode cutting.

[0020] In some embodiments of the first aspect of the present application, obtaining, based on the distance between the initial position and the detection reference, a shooting timing for the shooting device to shoot the cropping position and the detection reference includes:

[0021] Calculating a first angular displacement signal of an encoder on a conveying roller that conveys the pole piece according to a distance between the initial position and the detection reference, the encoder being configured to detect a conveying position of the conveying roller, and the photographing timing being when the encoder reaches the first angular displacement;

[0022] Controlling the photographing device to photograph the cutting position and the detection reference according to the photographing timing includes:

[0023] When the encoder reaches a first angular displacement, the photographing device is controlled to photograph the cutting position and the detection reference.

[0024] In the above technical solution, the shooting timing of the shooting device is obtained according to the angular displacement of the encoder on the conveying roller of the conveying pole piece, so that the shooting device can accurately shoot the detection reference and cutting position, thereby accurately obtaining the offset distance of the detection reference and cutting position.

[0025] In some embodiments of the first aspect of the present application, the pole piece cutting method further includes:

[0026] The cutting position is photographed by a photographing device to determine whether the notch at the cutting position is on the front side or the back side of the electrode.

[0027] In the above technical solution, judging whether the notch at the cutting position is on the front or back side of the electrode piece is helpful to confirm the feeding order to the front and back sides of the electrode piece, ensure the quality of the subsequent stacking, ensure accurate feeding to the front and back sides of the electrode piece, reduce the risk of assembly errors in the process of forming the electrode assembly, and improve the assembly efficiency of the electrode assembly.

[0028] In some embodiments of the first aspect of the present application, obtaining the cutting timing when the cutting position is transported to the cutting device according to the actual distance includes:

[0029] A second angular displacement signal of an encoder on a conveying roller conveying the pole piece is obtained by calculation according to the actual distance, and the cutting timing is when the encoder reaches the second angular displacement;

[0030] The controlling the cutting device to cut the cutting position according to the cutting timing includes:

[0031] The cutting device is controlled to cut the cutting position according to the encoder reaching the second angular displacement.

[0032] In the above technical solution, the second angular displacement signal of the encoder on the conveying roller that conveys the pole piece is calculated according to the actual distance from the cutting position to the cutting equipment, that is, the accurate cutting timing is obtained, which is conducive to accurately cutting the pole piece at the cutting position.

[0033] In some embodiments of the first aspect of the present application, the pole piece cutting method further includes:

[0034] After the last cutting position is obtained and the electrode piece is conveyed for a preset distance, determining whether the next cutting position is obtained after the last cutting position is obtained and the electrode piece is conveyed for a preset distance;

[0035] If the next cutting position is not obtained, an alarm signal is generated.

[0036] In the above technical solution, when the previous cutting position is transported away, if the next cutting position is not detected within the preset distance, it means that the structural design of the electrode is unreasonable or one or more devices in the detection system are faulty. An alarm signal needs to be generated to remind maintenance and troubleshoot the fault to avoid scrapping of the electrode and invalid detection work.

[0037] In a second aspect, an embodiment of the present application provides a pole piece cutting control system, comprising a cutting device, a shooting device and a controller; the cutting device is used for cutting pole pieces; the shooting device is configured to shoot a cutting position and a detection reference on the pole piece; the controller is communicatively connected to the shooting device and the cutting device, and the controller is configured to calculate an offset distance based on the cutting position and the detection reference, calculate an actual distance between the cutting position and the cutting device based on the offset distance and the distance between the detection reference and the cutting device, calculate a cutting timing based on the actual distance, and control the cutting device to cut the pole piece based on the cutting timing.

[0038] In the above technical solution, the offset distance between the detection reference and the cutting position is obtained by capturing the cutting position and the detection reference of the camera. This acquisition method is simple and convenient, which can improve the efficiency of obtaining the offset distance, improve the efficiency of electrode cutting, and facilitate continuous electrode cutting. After obtaining the offset distance, the exact time when the cutting position is transmitted to the cutting device can be determined, so that the cutting position can be accurately located at the cutting device, so that the controller can control the cutting device to accurately cut at the cutting position, thereby improving the cutting accuracy, thereby facilitating the improvement of the electrode cutting and forming quality and the reliability and safety of the battery using the electrode.

[0039] In some embodiments of the second aspect, the pole piece cutting control system further comprises: a fiber optic sensor disposed upstream of the camera, the fiber optic sensor being communicatively connected to the controller, the fiber optic sensor being configured to detect an initial position of a cutting position on the pole piece;

[0040] The controller is configured to obtain a shooting timing for the shooting device to shoot the cutting position and the detection reference based on a distance between the initial position and the detection reference, and the controller controls the shooting device to shoot the cutting position and the detection reference based on the shooting timing.

[0041] In the above technical solution, the initial position of the cutting position is obtained by an optical fiber sensor. The acquisition method is simple and convenient, which can improve the acquisition efficiency, improve the electrode cutting efficiency and facilitate continuous electrode cutting.

[0042] In some embodiments of the second aspect of the present application, the pole piece cutting control system further includes:

[0043] an encoder, disposed on a conveying roller for conveying the pole piece, the encoder being configured to detect a conveying position of the conveying roller, the encoder being communicatively connected to the controller;

[0044] The controller is further configured to calculate a first angular displacement signal of an encoder on a conveying roller conveying the pole piece according to a distance between the initial position and the detection reference, wherein the photographing timing is when the encoder reaches the first angular displacement;

[0045] The controller is further configured to control the photographing device to photograph the cutting position and the detection reference when the encoder reaches the first angular displacement.

[0046] In the above technical solution, the shooting timing of the shooting device to shoot the cutting position and the detection reference is obtained according to the angular displacement of the encoder, so that the shooting device can accurately shoot the cutting position and the detection reference and the cutting equipment can accurately cut the pole piece at the cutting position.

[0047] In some embodiments of the second aspect of the present application, the controller is further configured to calculate, based on the actual distance, a second angular displacement signal of an encoder on a conveying roller conveying the pole piece, and the cutting timing is when the encoder reaches the second angular displacement;

[0048] The controller is further configured to control the cutting device to cut the cutting position when the encoder reaches the second angular displacement.

[0049] In the above technical solution, the controller controls the cutting device to cut the pole piece according to the angular displacement signal of the encoder, so that the cutting device can accurately cut the pole piece at the cutting position.

[0050] In some embodiments of the second aspect of the present application, the photographing device includes a CCD detection camera.

[0051] In the above technical solution, the CCD camera has high shooting accuracy, thereby obtaining a more accurate offset distance. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0053] Figure 1A flowchart of a pole piece cutting method provided in some embodiments of the present application;

[0054] Figure 2 A schematic diagram of the relative relationship between the detection reference, cutting position and cutting equipment provided in some embodiments of the present application;

[0055] Figure 3 A flowchart of a pole piece cutting method provided in some other embodiments of the present application;

[0056] Figure 4 A flowchart of a pole piece cutting method provided in some further embodiments of the present application;

[0057] Figure 5 A schematic diagram of the structure of a pole piece cutting device provided in some embodiments of the present application;

[0058] Figure 6 for Figure 5 A schematic diagram of the shooting range of the shooting device;

[0059] Figure 7 A flowchart of a pole piece cutting method provided in some embodiments of the present application;

[0060] Figure 8 A flowchart of a pole piece cutting method provided in yet other embodiments of the present application;

[0061] Figure 9 A flowchart of a pole piece cutting method provided in yet other embodiments of the present application;

[0062] Figure 10 A flowchart of a pole piece cutting method provided in some further embodiments of the present application;

[0063] Figure 11 A schematic diagram of the relative relationship between the previous cutting position and the next cutting position.

[0064] Icons: 100-pole cutting control system; 10-detection reference; 20-shooting device; 20a-shooting range; 30-fiber optic sensor; 40-cutting equipment; 300-transfer roller; 2000-pole; 2100-cutting position; 2110-cutting hole; 2120-notch; 2100a-previous cutting position; 2100b-next cutting position. DETAILED DESCRIPTION

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0066] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0067] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0068] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0069] In the description of the embodiments of the present application, it should be noted that the indicated orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the product of the application is conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. These are merely for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present application. In addition, the terms "first," "second," "third," etc. are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0070] Currently, market developments indicate that power batteries are becoming increasingly widely used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. As power battery applications continue to expand, market demand is also growing.

[0071] In this application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application do not limit this. Battery cells may be cylindrical, flat, rectangular, or other shapes, etc., and the embodiments of this application do not limit this. Battery cells are generally divided into three types based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of this application do not limit this.

[0072] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode sheet, a negative electrode sheet, and a separator. A battery cell primarily operates by the movement of metal ions between the positive and negative electrode sheets. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The positive current collector uncoated with the positive active material layer protrudes from the positive current collector coated with the positive active material layer. The positive current collector uncoated with the positive active material layer serves as at least a portion of the positive electrode tab. In some embodiments, the positive electrode tab of the positive electrode sheet is the positive current collector uncoated with the positive active material layer. In other embodiments, to ensure the structural strength of the positive electrode tab, the positive tab includes both the positive current collector uncoated with the positive active material layer and the positive current collector partially coated with the positive active material layer. For lithium-ion batteries, for example, the positive current collector can be made of aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, among others. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer. The negative electrode current collector not coated with the negative electrode active material layer serves as at least a portion of the negative electrode tab. In some embodiments, the negative electrode tab of the negative electrode sheet is the negative electrode current collector not coated with the negative electrode active material layer. In other embodiments, to ensure the structural strength of the negative electrode tab, the negative electrode tab includes the negative electrode current collector not coated with the negative electrode active material layer and the positive electrode current collector partially coated with the negative electrode active material layer. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon, silicon, or other materials. To ensure that high currents can pass without melting, multiple positive electrode tabs are stacked together, and multiple negative electrode tabs are stacked together. The separator can be made of materials such as PP (polypropylene) or PE (polyethylene). Furthermore, the electrode assembly can be a wound or laminated structure, but the embodiments of the present application are not limited to this.

[0073] For electrode assemblies, the positive and negative electrodes must meet certain length requirements to ensure the wound electrode assembly has a sufficient number of turns to meet the battery's performance requirements. Therefore, strict control over the length of the positive and negative electrodes is required, requiring cutting equipment to accurately cut the electrodes at the cutting position.

[0074] The inventors found that due to manufacturing errors and installation errors in various parts of the electrode cutting equipment, the cutting position of the electrode cannot accurately correspond to the cutting equipment, resulting in low cutting accuracy and large length errors of the cut electrode, thereby reducing the molding quality of the electrode and the reliability and safety of the battery cell using the electrode.

[0075] Based on the above considerations, in order to alleviate the problem of low cutting accuracy caused by low cutting position positioning accuracy when cutting the electrode, the inventor has conducted in-depth research and provided a electrode cutting method, which obtains the offset distance between the detection reference and the cutting position of the electrode; then obtains the actual distance between the cutting position and the cutting device based on the offset distance and the distance between the detection reference and the cutting device; and obtains the timing of transporting the cutting position to the cutting device based on the actual distance, so that the cutting device cuts the cutting position.

[0076] By obtaining the offset distance between the detection reference and the cutting position of the electrode, it is equivalent to obtaining the deviation from the detection reference caused by manufacturing errors, installation errors and other reasons of the conveying equipment during the transmission of the electrode; then the actual distance between the cutting position and the cutting equipment is obtained based on the offset distance and the distance between the detection reference and the cutting equipment, which is equivalent to obtaining the actual position of the cutting position, so that the exact time when the cutting position is conveyed to the cutting equipment can be obtained, so that the cutting position can be accurately positioned at the cutting equipment, so that the cutting equipment can accurately cut at the cutting position, thereby improving the cutting accuracy, which is beneficial to improving the cutting and forming quality of the electrode and the reliability and safety of the battery using the electrode.

[0077] The electrode cutting method disclosed in the embodiment of the present application can also be used in other fields that require cutting and positioning, such as film packaging, food production, etc. This helps to alleviate the problem of low cutting accuracy caused by low cutting position positioning accuracy.

[0078] For the convenience of description, the following embodiments illustrate the method for cutting the pole piece 2000 by taking the cutting of the pole piece in the embodiment of the present application as an example.

[0079] Please refer to Figure 1 、 Figure 2 , the pole piece 2000 cutting method includes:

[0080] S100, obtaining an offset distance between the detection reference 10 and the cutting position 2100 of the pole piece 2000;

[0081] S200 , obtaining the actual distance between the cutting position 2100 and the cutting device 40 according to the offset distance and the distance between the detection reference 10 and the cutting device 40 ;

[0082] S300 , obtaining a cutting timing when the cutting position 2100 is transported to the cutting device 40 according to the actual distance, and controlling the cutting device 40 to cut the cutting position 2100 according to the cutting timing.

[0083] The cutting position 2100 is the position where the electrode piece 2000 is cut by the cutting device 40. The electrode piece 2000 is divided into two after cutting at the cutting position 2100. The cutting device 40 can be a cutting knife, a cutting laser, or the like.

[0084] The position of the detection reference 10 is fixed, and the distance between the detection reference 10 and the cutting device 40 is fixed and known. There are many reasons for the offset distance between the detection reference 10 and the cutting position 2100, such as manufacturing errors and installation errors of various structures of the pole piece cutting control system 100.

[0085] Since the distance between the detection reference 10 and the cutting device 40 is known, the actual distance from the cutting position 2100 to the cutting device 40 can be obtained by combining the offset distance between the detection reference 10 and the cutting position 2100. This means that we can know how far the electrode 2000 needs to be transported so that the cutting position 2100 can reach the position directly opposite the cutting device 40. When the cutting position 2100 reaches the position directly opposite the cutting device 40, which is the accurate cutting time, the cutting device 40 can be controlled to cut the electrode 2000, and the cutting position of the cutting device 40 is the accurate cutting position 2100. For example, Figure 2 As shown, the cutting device 40 is located downstream of the detection reference 10, and the pole piece 2000 is transported from the detection reference 10 to the cutting device 40. The distance from the detection reference 10 to the cutting device 40 is defined as L1, and the offset distance of the cutting position 2100 relative to the detection reference 10 is L10. The cutting position 2100 and the detection reference 10 are located on the same side of the cutting device 40. If the cutting position 2100 is closer to the cutting device 40 relative to the detection reference 10, the actual distance L20 from the cutting position 2100 to the cutting device 40 satisfies: L20 = L1 - L10 ( Figure 2 ), if the cutting position 2100 is further away from the cutting device 40 relative to the detection reference 10, the actual distance L20 from the cutting position 2100 to the cutting device 40 satisfies: L20=L1+L10. Then the pole piece 2000 needs to be transported a distance L20 to the cutting position 2100 to reach the position facing the cutting device 40. After obtaining the offset distance L10 of the cutting position 2100 relative to the detection reference 10, the pole piece 2000 continues to be transported a distance L20, then it is considered that the cutting position 2100 has been transported to the cutting time of the cutting device 40, and the cutting device 40 is controlled to cut the pole piece 2000, so that the cutting device 40 can cut the pole piece 2000 at the accurate cutting position 2100.

[0086] It should be noted that the terms "upstream" and "downstream" mentioned above and below in the embodiments of this application refer to the order of production, with upstream referring to the first component in the production sequence and downstream referring to the last component in the production sequence. They do not define the spatial positions of the components. For example, if the inspection reference 10 is located upstream of the cutting device 40, the cutting position 2100 line on the electrode 2000 passes through the inspection reference 10 and then through the cutting device 40.

[0087] By obtaining the offset distance between the detection reference 10 and the cutting position 2100 of the electrode 2000, it is equivalent to obtaining the deviation from the detection reference 10 caused by the manufacturing error, installation error and other reasons of the conveying equipment during the transmission of the electrode 2000; then the actual distance between the cutting position 2100 and the cutting device 40 is obtained based on the offset distance and the distance between the detection reference 10 and the cutting device 40, which is equivalent to obtaining the actual position of the cutting position 2100, so that the accurate cutting time when the cutting position 2100 is conveyed to the cutting device 40 can be obtained, so that the cutting position 2100 can be accurately positioned at the cutting device 40, so that the cutting device 40 can accurately cut at the cutting position 2100, thereby improving the cutting accuracy, which is beneficial to improving the cutting and forming quality of the electrode 2000 and the reliability and safety of the battery using the electrode 2000.

[0088] like Figure 2 、 Figure 3 As shown, in some embodiments, obtaining the offset distance between the detection reference 10 and the cutting position 2100 of the pole piece 2000 includes:

[0089] The cropping position 2100 and the detection reference 10 are photographed by the photographing device 20 to obtain an offset distance between the detection reference 10 of the photographing device 20 and the cropping position 2100 .

[0090] The photographing device 20 is disposed upstream of the cutting device 40 .

[0091] The photographing device 20 can be a CCD (Charge Coupled Device) camera, a mobile phone camera, a video camera, etc. After photographing, it can accurately observe whether the cutting position 2100 is closer to or farther away from the cutting device 40 relative to the detection reference 10, thereby facilitating the determination of the offset distance between the cutting position 2100 and the detection reference 10 and the actual distance between the cutting position 2100 and the cutting device 40. In this embodiment, the detection reference 10 is a reference built into the photographing device 20.

[0092] In other embodiments, as needed, the offset distance between the detection reference 10 and the cutting position 2100 may be obtained in other ways.

[0093] The cutting position 2100 and the detection reference 10 are photographed by the shooting device 20 to obtain the offset distance between the detection reference 10 of the shooting device 20 and the cutting position 2100. The acquisition method is simple and convenient, which can improve the efficiency of obtaining the offset distance, thereby improving the cutting efficiency of the pole piece 2000 and facilitating continuous cutting of the pole piece 2000.

[0094] like Figure 4 、 Figure 5 、 Figure 6 As shown, in some embodiments, the pole piece 2000 cutting method further includes:

[0095] S400, obtaining the initial position of the cutting position 2100;

[0096] S500 , obtaining a shooting timing for the shooting device 20 to shoot the cutting position 2100 and the detection reference 10 according to the distance between the initial position and the detection reference 10 , and controlling the shooting device 20 to shoot the cutting position 2100 and the detection reference 10 according to the shooting timing.

[0097] The initial position of the cutting position 2100 is upstream of the detection reference 10. Knowing the distance between the initial position and the detection reference 10 allows us to determine how far the pole piece 2000 needs to be transported to bring the cutting position 2100 within the imaging range 20a of the camera 20. This allows us to determine the timing for the camera 20 to capture images of the cutting position 2100 and the detection reference 10. Once the cutting position 2100 is within the imaging range 20a of the camera 20, the camera 20 can be controlled to capture the cutting position 2100. In other words, the camera 20 triggers the capture based on the distance between the detection reference 10 and the initial position.

[0098] For example, if the distance between the initial position and the detection reference 10 is defined as L2, the electrode piece 2000 needs to be transported a distance L2 to the cutting position 2100 to reach the imaging range 20a of the imaging device 20. After obtaining the initial position of the cutting position 2100, if the electrode piece 2000 continues to be transported a distance L2, it is considered that the cutting position 2100 has been transported to the imaging range 20a of the imaging device 20 and the imaging device 20 is controlled to capture the cutting position 2100.

[0099] According to the distance between the initial position and the detection reference 10, the shooting timing of the cutting position 2100 being transported to the shooting device 20 to shoot the cutting position 2100 and the detection reference 10 is obtained, and the shooting device 20 is controlled to shoot the cutting position 2100 and the detection reference 10 according to the shooting timing, so that the shooting device 20 can accurately shoot the cutting position 2100 and the detection reference 10, which is conducive to obtaining the accurate offset distance between the detection reference 10 and the cutting position 2100.

[0100] like Figure 5 、 Figure 6 、 Figure 7 As shown, in some embodiments, obtaining the initial position of the cropping position 2100 includes:

[0101] The optical fiber sensor 30 detects that the cutting position 2100 has reached the initial position.

[0102] The fiber optic sensor 30 is positioned upstream of the camera 20. The position of the fiber optic sensor 30 is fixed. Since the cutting position 2100 can only be detected once it reaches the position of the fiber optic sensor 30, the initial position of the cutting position 2100 can be understood as the position where the fiber optic sensor 30 directly faces the pole piece 2000. Therefore, the distance between the initial position of the cutting position 2100 and the detection reference 10 of the camera 20 can be understood as the distance between the fiber optic sensor 30 and the detection reference 10 of the camera 20.

[0103] like Figure 5 As shown, the optical fiber sensor 30 includes a transmitter and a receiver, which are respectively located on both sides of the thickness direction of the pole piece 2000. The receiver is used to receive the optical signal emitted by the transmitter. The cutting position 2100 is provided with a cutting hole 2110 and a notch 2120. The cutting hole 2110 passes through both sides of the thickness direction of the pole piece 2000. When the cutting position 2100 is transported to the optical fiber sensor 30, the optical signal emitted by the transmitter can pass through the cutting hole 2110 and be received by the receiver, that is, the cutting position 2100 is detected, and it is detected that the cutting position 2100 has reached the initial position. When the cutting position 2100 has not moved to the optical fiber sensor 30, the optical signal emitted by the transmitter cannot pass through the pole piece 2000 and be received by the receiver.

[0104] Of course, in other embodiments, other detection methods may be used to detect whether the cutting position 2100 reaches the initial position.

[0105] The optical fiber sensor 30 is used to detect whether the cutting position 2100 reaches the initial position. The acquisition method is simple and convenient, which can improve the acquisition efficiency, improve the cutting efficiency of the pole piece 2000 and facilitate continuous cutting of the pole piece 2000.

[0106] Please continue to see Figure 8 In some embodiments, obtaining the shooting timing of the camera 20 shooting the cropping position 2100 and the detection reference 10 based on the distance between the initial position and the detection reference 10 includes:

[0107] The first angular displacement signal of the encoder on the conveying roller 300 of the conveying pole piece 2000 is calculated based on the distance between the initial position and the detection reference 10. The encoder is configured to detect the conveying position of the conveying roller 300. The shooting timing is when the encoder reaches the first angular displacement.

[0108] Controlling the photographing device to photograph the cropping position 2100 and the detection reference 10 according to the photographing timing includes:

[0109] When the encoder reaches the first angular displacement, the photographing device is controlled to photograph the cutting position 2100 and the detection reference 10 .

[0110] The encoder converts angular position or linear position into an electrical signal. The encoder is set on the conveyor roller 300, and the number of revolutions of the conveyor roller 300 corresponds to the angular displacement of the encoder. After the optical fiber sensor 30 detects the cutting position 2100, it obtains the angular displacement of the encoder and thus obtains the initial position of the cutting position 2100. For example, when the conveyor roller 300 conveys the pole piece 2000 so that the cutting position 2100 is conveyed to the optical fiber sensor 30, the angular displacement of the encoder is X10, and the distance between the initial position and the detection reference 10 is L2. After theoretical calculation, L2 corresponds to the angular displacement of the encoder X11. Then, when the conveyor roller 300 conveys the pole piece 2000 so that the cutting position 2100 reaches the shooting range 20a of the shooting device 20 from the initial position, the angular displacement corresponding to the encoder X1 = X10 + X11. X1 is the first angular displacement. When the angular displacement of the encoder reaches X1, it is determined that the shooting time has arrived, and it is also the time for the cutting position 2100 to be transported to the shooting range 20a of the shooting device 20. Then, according to the angular displacement X1 (first angular displacement) of the encoder, the shooting device 20 is controlled to shoot the cutting position 2100 and the detection reference 10.

[0111] The shooting timing of the shooting device 20 is obtained according to the angular displacement of the encoder on the conveying roller 300 of the conveying pole piece 2000, so that the shooting device 20 can accurately shoot the detection reference 10 and the cutting position 2100, thereby accurately obtaining the offset distance between the detection reference 10 and the cutting position 2100.

[0112] like Figure 9 As shown, in some embodiments, the pole piece 2000 cutting method further includes:

[0113] S600 , photographing the cutting position 2100 by the photographing device 20 , and determining whether the notch 2120 of the cutting position 2100 is on the front side or the back side of the pole piece 2000 .

[0114] For foldable electrode assemblies, the notch 2120 at the cutting location 2100 of the electrode sheet 2000 is located at the bend during folding, reducing the possibility of the bend being broken or squeezed. For example, if the electrode sheet 2000 being cut is a negative electrode sheet 2000, the positive electrode sheet 2000 needs to be fed from both sides of the thickness direction of the negative electrode sheet 2000. Depending on whether the notch 2120 is located on the front or back side, the positive electrode sheet 2000 can be fed to the front or back side.

[0115] Determining whether the notch 2120 at the cutting position 2100 is on the front or back side of the electrode 2000 is helpful in confirming the order of feeding to the front and back sides of the electrode 2000, ensuring the quality of the subsequent stacking, and ensuring accurate feeding to the front and back sides of the electrode 2000, thereby reducing the risk of feeding errors in the process of forming the electrode assembly and improving the assembly efficiency of the electrode assembly.

[0116] Please continue to see Figure 9 In some embodiments, obtaining the cutting timing when the cutting position 2100 is transported to the cutting device 40 according to the actual distance includes:

[0117] The second angular displacement signal of the encoder on the conveying roller 300 of the conveying pole piece 2000 is obtained by calculation based on the actual distance, and the cutting time is when the encoder reaches the second angular displacement;

[0118] Controlling the cutting device 40 to cut the cutting position 2100 according to the cutting timing includes:

[0119] The cutting device 40 is controlled to cut at the cutting position 2100 according to the encoder reaching the second angular displacement.

[0120] For example, when the conveying roller 300 conveys the electrode piece 2000 so that the cutting position 2100 reaches the shooting range 20a of the camera 20, the angular displacement corresponding to the encoder is X1 (first angular displacement). The actual distance L20 between the cutting position 2100 and the cutting device 40 is theoretically calculated, and the angular displacement of the encoder corresponding to L20 is X12. When the conveying roller 300 conveys the electrode piece 2000 so that the cutting position 2100 reaches the cutting device 40 from the shooting range 20a of the camera 20, the angular displacement X2 corresponding to the encoder is X1+X12, where X2 is the second angular displacement. When the angular displacement of the encoder reaches X2, that is, when the cutting time is reached, that is, when the cutting position 2100 is conveyed to the cutting device 40, the cutting device 40 is controlled to cut the electrode piece 2000 according to the angular displacement X2 (second angular displacement) of the encoder.

[0121] The second angular displacement signal of the encoder on the conveying roller 300 that conveys the pole piece 2000 is calculated based on the actual distance from the cutting position 2100 to the cutting device 40, that is, the accurate cutting timing is obtained, which is conducive to accurately cutting the pole piece 2000 at the cutting position 2100.

[0122] See also Figure 5 、 Figure 10 、 Figure 11 In some embodiments, the pole piece 2000 cutting method further includes:

[0123] S700, after the last cutting position 2100a is obtained and the pole piece 2000 is conveyed for a preset distance, determining whether the next cutting position 2100b is obtained after the last cutting position 2100a is obtained and the pole piece 2000 is conveyed for a preset distance;

[0124] If the next cutting position 2100b is not obtained, an alarm signal is generated.

[0125] The distance between two adjacent cutting positions 2100 is defined as L3. The pole piece 2000 is continuously transported. When the initial position of the previous cutting position 2100a is obtained, under normal circumstances, the pole piece 2000 is transported for a distance of L3. + The optical fiber sensor 30 can detect the next cutting position 2100b within the range of a. If the next one is detected, continue to perform the above steps. If the next cutting device is not detected, it may be that the pole piece 2000 has no cutting hole 2110 there or the cutting hole 2110 is punched through, or the optical fiber sensor 30 is faulty, or other equipment has failed, then an alarm signal is generated to remind that maintenance is required. By combining theoretical prediction with actual detection, in the case of a small failure of the optical fiber sensor 30, the time when the next cutting position 2100b reaches the shooting range 20a of the shooting device 20 can be obtained by theoretical calculation, so that the shooting device can be used for detection to avoid missing data of the pole piece 2000, thereby effectively reducing the scrap rate in the manufacturing process of the electrode assembly.

[0126] in, + a represents the allowable error range of the distance between two adjacent cutting positions 2100.

[0127] The preset distance can be nL3 + a and n are natural numbers greater than or equal to 1.

[0128] After the previous cutting position 2100a is transported away, if the next cutting position 2100b is not detected within the preset distance, it means that the structural design of the pole piece 2000 is unreasonable or one or more devices in the detection system are faulty. An alarm signal needs to be generated to remind maintenance and troubleshoot to avoid the pole piece 2000 being scrapped and the detection work being invalid.

[0129] Please continue to see Figure 5, an embodiment of the present application provides a pole piece cutting control system 100, the pole piece cutting control system 100 includes a cutting device 40, a shooting device 20 and a controller (not shown in the figure); the cutting device 40 is used to cut the pole piece 2000; the shooting device 20 is configured to shoot the cutting position 2100 and the detection reference 10 on the pole piece 2000; the controller is communicated with the shooting device 20 and the cutting device 40, and the controller is configured to calculate the offset distance according to the cutting position 2100 and the detection reference 10, calculate the actual distance between the cutting position 2100 and the cutting device 40 according to the offset distance and the distance between the detection reference 10 and the cutting device 40, calculate the cutting timing according to the actual distance, and control the cutting device to cut the pole piece according to the cutting timing.

[0130] The camera 20 is disposed upstream of the cutting device 40, and the cutting device 40 is disposed downstream of the camera 20. The controller controls the angular displacement of an encoder (not shown) disposed on the conveying roller 300 that conveys the pole piece 2000 to control the camera 20 to capture the cutting position 2100 and the detection reference 10, as well as to control the cutting device 40 to cut the pole piece 2000. The controller is configured to receive an electrical signal representing the angular position of the encoder and control the camera 20 to capture the image and / or the cutting device 40 to cut the pole piece according to the electrical signal.

[0131] The offset distance between the detection reference 10 of the camera 20 and the cutting position 2100 is obtained by photographing the cutting position 2100 and the detection reference 10 of the camera 20. The acquisition method is simple and convenient, which can improve the efficiency of obtaining the offset distance, improve the efficiency of cutting the electrode 2000, and facilitate continuous cutting of the electrode 2000. After obtaining the offset distance, the exact time when the cutting position 2100 is transported to the cutting device 40 can be obtained, so that the cutting position 2100 can be accurately positioned at the cutting device 40, so that the controller can control the cutting device 40 to accurately cut at the cutting position 2100, improve the cutting accuracy, and thus help improve the cutting and forming quality of the electrode 2000 and the reliability and safety of the battery using the electrode 2000.

[0132] Please continue to see Figure 5 In some embodiments, the pole piece cutting control system 100 further includes: an optical fiber sensor 30, which is arranged upstream of the shooting device 20, and the optical fiber sensor 30 is communicatively connected to the controller, and the optical fiber sensor 30 is configured to detect the initial position of the cutting position on the pole piece 2000; the controller also obtains the shooting timing of the shooting device 20 shooting the cutting position 2100 and the detection reference 10 based on the distance between the initial position and the detection reference 10, and the controller controls the shooting device 20 to shoot the cutting position 2100 and the detection reference 10 according to the shooting timing.

[0133] The fiber optic sensor 30 is positioned upstream of the camera 20. After detecting the cutting position 2100, the fiber optic sensor 30 determines the initial position of the cutting position 2100 based on the corresponding angular displacement of the encoder. Combined with the angular displacement of the encoder corresponding to the distance between the initial position and the detection reference 10 of the camera 20, the angular displacement of the encoder when the conveyor roller 300 transported the cutting position 2100 from the initial position to the imaging range 20a of the imaging position can be determined. After the cutting position 2100 is transported to the imaging range 20a of the camera 20, the controller controls the camera 20 to capture images based on the electrical signal representing the angular displacement of the encoder when the cutting position 2100 was transported from the initial position to the imaging range 20a of the imaging position.

[0134] The initial position of the cutting position 2100 is obtained by the optical fiber sensor 30 . The obtaining method is simple and convenient, which can improve the obtaining efficiency, improve the cutting efficiency of the pole piece 2000 and facilitate the continuous cutting of the pole piece 2000 .

[0135] In some embodiments, the pole piece cutting control system 100 further includes: an encoder (not shown in the figure), which is disposed on the conveying roller 300 that conveys the pole piece 2000, and is configured to detect the conveying position of the conveying roller 300, and the encoder is communicatively connected to the controller;

[0136] The controller is configured to calculate the first angular displacement signal of the encoder on the conveying roller 300 of the conveying pole piece 2000 based on the distance between the initial position and the detection reference 10, and the shooting timing is when the encoder reaches the first angular displacement; the controller is also configured to control the shooting device 20 to shoot the cutting position 2100 and the detection reference 10 when the encoder reaches the first angular displacement.

[0137] After cutting position 2100 reaches the imaging range 20a of camera 20, the encoder's angular displacement corresponding to cutting position 2100 at this point, combined with the encoder's angular displacement corresponding to the actual distance between cutting position 2100 and cutting device 40, can be used to determine the encoder's angular displacement, i.e., the first angular displacement, when the conveyor roller 300 transports cutting position 2100 from imaging range 20a of camera 20 to cutting device 40. After cutting position 2100 is transported to cutting device 40, the encoder's angular displacement reaches the first angular displacement, i.e., the timing for capturing an image. Based on the first angular displacement, the controller controls camera 20 to capture images of cutting position 2100 and detection reference 10.

[0138] The shooting timing of the shooting device 20 to shoot the cutting position 2100 and the detection reference 10 is obtained according to the angular displacement of the encoder, so that the shooting device 20 can accurately shoot the cutting position 2100 and the detection reference 10, which is convenient for controlling the cutting equipment 40 to accurately cut the pole piece 2000 at the cutting position 2100.

[0139] In some embodiments, the controller is also configured to calculate the second angular displacement signal of the encoder on the conveying roller 300 of the conveying pole piece 2000 based on the actual distance, and the cutting timing is when the encoder reaches the second angular displacement; the controller is also configured to control the cutting device 40 to cut the cutting position 2100 when the encoder reaches the second angular displacement.

[0140] When cutting position 2100 is within the imaging range 20a of camera 20, the encoder's angular displacement is a first angular displacement. Combined with the actual distance between cutting position 2100 and cutting device 40 within imaging range 20a of camera 20, the controller can calculate the encoder's angular displacement when cutting position 2100 reaches cutting device 40, i.e., the second angular displacement, which also indicates the cutting timing. When the encoder's angular displacement is the second angular displacement, the controller controls cutting device 40 to cut pole piece 2000 at cutting position 2100.

[0141] The controller controls the cutting device 40 to cut the pole piece 2000 according to the angular displacement signal of the encoder, so that the cutting device 40 can accurately cut the pole piece 2000 at the cutting position 2100 .

[0142] Please continue to see Figure 5 In some embodiments, the photographing device 20 includes a CCD detection camera.

[0143] A CCD is a semiconductor device that converts optical images into digital signals. CCD cameras are compact, lightweight, unaffected by magnetic fields, and resistant to vibration and impact. This allows for high-precision capture, enabling more accurate offset distances.

[0144] The embodiment of the present application provides a method for forming a pole piece 2000, comprising:

[0145] Detecting the initial position of the cutting position 2100 according to the optical fiber sensor 30;

[0146] The first angular displacement signal of the encoder on the conveying roller 300 of the conveying pole piece 2000 is calculated based on the distance between the initial position and the detection reference 10 of the CCD camera, thereby obtaining the shooting timing of the CCD camera. The shooting timing is when the encoder reaches the first angular displacement. The CCD camera is controlled to shoot the cutting position 2100 and the detection reference 10 based on the first angular displacement.

[0147] The cutting position 2100 and the detection reference 10 are photographed by a CCD camera to obtain an offset distance between the detection reference 10 of the CCD camera and the cutting position 2100;

[0148] Obtaining the actual distance between the cutting position 2100 and the cutting device 40 according to the offset distance and the distance between the detection reference 10 and the cutting device 40;

[0149] The controller calculates the second angular displacement signal of the encoder on the conveying roller 300 of the conveying pole piece 2000 based on the actual distance, thereby obtaining the cutting timing when the cutting position 2100 reaches the cutting device 40. The cutting timing is when the encoder reaches the second angular displacement. The controller uses the second angular displacement to control the cutting device 40 to cut the cutting position 2100.

[0150] By cutting the pole piece 2000 using the above method, the cutting position 2100 can be accurately positioned at the cutting device 40, so that the cutting device 40 can accurately cut at the cutting position 2100, thereby improving the cutting accuracy, which is beneficial to improving the cutting and forming quality of the pole piece 2000 and the reliability and safety of the battery using the pole piece 2000.

[0151] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A pole piece cutting method, characterized in that: include: Obtaining the offset distance between the detection reference and the cutting position of the pole piece; Obtaining an actual distance between the cutting position and the cutting device according to the offset distance and the distance between the detection reference and the cutting device; The cutting timing when the cutting position is transported to the cutting device is acquired according to the actual distance, and the cutting device is controlled to cut the cutting position according to the cutting timing.

2. The pole piece cutting method according to claim 1, characterized in that: The step of obtaining the offset distance between the detection reference and the cutting position of the electrode piece includes: The cutting position and the detection reference are photographed by a photographing device to obtain the offset distance between the detection reference of the photographing device and the cutting position.

3. The pole piece cutting method according to claim 2, characterized in that: The pole piece cutting method further comprises: Obtaining the initial position of the cutting position; According to the distance between the initial position and the detection reference, the shooting timing of the shooting device to shoot the cutting position and the detection reference is obtained, and according to the shooting timing, the shooting device is controlled to shoot the cutting position and the detection reference.

4. The pole piece cutting method according to claim 3, characterized in that: The obtaining of the initial position of the cutting position includes: The optical fiber sensor detects that the cutting position reaches the initial position.

5. The pole piece cutting method according to claim 3, characterized in that: The acquiring, based on the distance between the initial position and the detection reference, a shooting timing for the shooting device to shoot the cropping position and the detection reference, includes: Calculating a first angular displacement signal of an encoder on a conveying roller that conveys the pole piece according to a distance between the initial position and the detection reference, the encoder being configured to detect a conveying position of the conveying roller, and the photographing timing being when the encoder reaches the first angular displacement; Controlling the photographing device to photograph the cutting position and the detection reference according to the photographing timing includes: When the encoder reaches a first angular displacement, the photographing device is controlled to photograph the cutting position and the detection reference.

6. The pole piece cutting method according to claim 2, characterized in that: The pole piece cutting method further comprises: The cutting position is photographed by a photographing device to determine whether the notch at the cutting position is on the front side or the back side of the electrode.

7. The pole piece cutting method according to any one of claims 1 to 6, characterized in that: The obtaining, based on the actual distance, of a cutting timing at which the cutting position is transported to the cutting device comprises: A second angular displacement signal of an encoder on a conveying roller conveying the pole piece is obtained by calculation according to the actual distance, and the cutting timing is when the encoder reaches the second angular displacement; The controlling the cutting device to cut the cutting position according to the cutting timing includes controlling the cutting device to cut the cutting position according to the encoder reaching the second angular displacement.

8. The pole piece cutting method according to any one of claims 1 to 6, characterized in that: The pole piece cutting method further comprises: After the last cutting position is obtained and the electrode piece is conveyed for a preset distance, determining whether the next cutting position is obtained after the last cutting position is obtained and the electrode piece is conveyed for a preset distance; If the next cutting position is not obtained, an alarm signal is generated.

9. A pole piece cutting control system, characterized in that: include: Cutting equipment, used for cutting pole pieces; a photographing device configured to photograph a cutting position and a detection reference on the electrode piece; as well as A controller is communicatively connected to the photographing device and the cutting device, and the controller is configured to calculate an offset distance based on the cutting position and the detection reference, calculate an actual distance between the cutting position and the cutting device based on the offset distance and the distance between the detection reference and the cutting device, calculate a cutting timing based on the actual distance, and control the cutting device to cut the pole piece based on the cutting timing.

10. The pole piece cutting control system according to claim 9, characterized in that: The pole piece cutting control system further includes: an optical fiber sensor disposed upstream of the photographing device, the optical fiber sensor being in communication with the controller, and configured to detect an initial position of a cutting position on the pole piece; The controller is configured to obtain a shooting timing for the shooting device to shoot the cutting position and the detection reference based on a distance between the initial position and the detection reference, and the controller controls the shooting device to shoot the cutting position and the detection reference based on the shooting timing.

11. The pole piece cutting control system according to claim 10, characterized in that: The pole piece cutting control system further includes: an encoder, disposed on a conveying roller for conveying the pole piece, the encoder being configured to detect a conveying position of the conveying roller, the encoder being communicatively connected to the controller; The controller is further configured to calculate a first angular displacement signal of an encoder on a conveying roller conveying the pole piece according to a distance between the initial position and the detection reference, wherein the photographing timing is when the encoder reaches the first angular displacement; The controller is further configured to control the photographing device to photograph the cutting position and the detection reference when the encoder reaches the first angular displacement.

12. The pole piece cutting control system according to claim 11, characterized in that: The controller is further configured to calculate a second angular displacement signal of an encoder on a conveying roller conveying the pole piece according to the actual distance, and the cutting timing is when the encoder reaches the second angular displacement; The controller is further configured to control the cutting device to cut the cutting position when the encoder reaches the second angular displacement.

13. The pole piece cutting control system according to claim 9, characterized in that: The shooting device includes a CCD detection camera.

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