Electrode sheet inspection method and system

Abstract

Disclosed in the present application are an electrode sheet inspection method and system. The method comprises: acquiring an image to be subjected to inspection, which is collected from an electrode sheet; on the basis of preset edge-capture region information, determining at least one edge-capture region from said image, wherein the preset edge-capture region information comprises position information and / or size information of the edge-capture region; performing boundary detection on each edge-capture region, so as to obtain a first boundary line in each edge-capture region, wherein the first boundary line is used for delineating different partitions of the electrode sheet that are arranged in a widthwise direction; and using the first boundary line in each edge-capture region to determine width information related to the electrode sheet. In this way, the present application can implement automatic inspection for an electrode sheet.

Description

Pole piece detection method and system

[0001]

Cross-reference

[0002] This application claims priority to the Chinese patent application filed with the China Patent Office on December 5, 2023, with application number 2023116622920 and application name “Pole Detection Method and System”, the entire contents of which are incorporated by reference into this application.

Technical field

[0003] The present application relates to the field of battery technology, and in particular to a pole piece detection method and system. [Background Technology]

[0004] Lithium battery pole pieces consist of two parts: a substrate and a coating. The substrate is copper or aluminum foil, and the coating is the active material. The pole piece is produced by coating the active material onto the substrate, followed by drying, compacting, and slitting. Abnormalities in the manufactured pole piece, such as metal leaks, bubbles, pinholes in the coating area on the pole piece surface, or non-compliant dimensions of the coating area, can result in poor capacity consistency, poor safety, and high self-discharge in the resulting battery, seriously impacting battery quality. Therefore, pole piece testing is a pressing issue.

[0005] [Summary of the invention]

[0006] This application at least provides a pole piece detection method and system.

[0007] In a first aspect, the present application provides a method for detecting a pole piece, the method comprising: obtaining an image to be detected obtained by capturing the pole piece; determining at least one edge-grabbing area in the image to be detected based on preset edge-grabbing area information, the preset edge-grabbing area information including position information and / or size information of the edge-grabbing area; performing boundary detection on each edge-grabbing area to obtain a first boundary line in each edge-grabbing area, the first boundary line being used to divide the pole piece into different partitions arranged in the width direction; and determining width information related to the pole piece using the first boundary line in each edge-grabbing area.

[0008] In the above scheme, at least one edge-grabbing region is determined in the image to be inspected based on the preset edge-grabbing region information. Boundary detection is performed on each edge-grabbing region to obtain a first boundary line within each edge-grabbing region. Width information associated with the electrode piece is then determined using the first boundary line within each edge-grabbing region. This enables automatic detection of the electrode piece.

[0009] Furthermore, the above scheme can also use the preset edge-grabbing area to determine the width information related to the pole piece, thereby realizing automatic detection of the width information related to the pole piece; in addition, the preset edge-grabbing area does not require user setting, thereby improving the detection efficiency of the width information related to the pole piece.

[0010] In some embodiments, at least one edge-grabbing region is determined in the image to be inspected based on the preset edge-grabbing region information, including: if the electrode is an anode electrode, at least four edge-grabbing regions are determined in the image to be inspected based on the preset edge-grabbing region information; or if the electrode is a cathode electrode, at least six edge-grabbing regions are determined in the image to be inspected based on the preset edge-grabbing region information. Boundary detection of each edge-grabbing region is performed using multiple threads, with each edge-grabbing region being detected using a separate thread.

[0011] In the above solution, the boundary detection of each edge-grabbing area is performed by multiple threads, that is, multiple first boundary lines in the image to be detected are captured simultaneously to speed up the operation and reduce the processing time of a single image to be detected.

[0012] In some embodiments, before determining at least one edge-grabbing area in the image to be detected based on preset edge-grabbing area information, the electrode detection method also includes: obtaining a sample image obtained by collecting an electrode; capturing several second boundary lines in the sample image; and using each second boundary line to obtain information on the edge-grabbing area corresponding to each second boundary line to obtain the preset edge-grabbing area information.

[0013] In the above solution, the preset edge-grabbing area information can be automatically determined and generated, which is more efficient in determining and generating the preset edge-grabbing area information.

[0014] In some embodiments, capturing several second boundary lines in the sample image includes: determining a boundary detection area of ​​the sample image based on area setting information; capturing several second boundary lines from the boundary detection area; and / or, using each second boundary line, obtaining information of the grabbing area corresponding to each second boundary line to obtain preset grabbing area information, including at least one of the following steps: for each second boundary line, obtaining position information of a first preset position point of the second boundary line as position information of a second preset position point in the grabbing area corresponding to the second boundary line; obtaining size information of the grabbing area corresponding to the second boundary line.

[0015] In the above solution, the second boundary line in the boundary detection area can be flexibly determined according to the area setting information; and / or the size information of the edge grabbing area can be flexibly adjusted.

[0016] In some embodiments, boundary detection is performed on each edge-grabbing area to obtain a first boundary line in each edge-grabbing area, including: for each edge-grabbing area, using the grayscale changes in the edge-grabbing area to find a number of boundary points, and the grayscale changes between the boundary points and adjacent pixel points meet the boundary grayscale change requirements; using the several boundary points in the edge-grabbing area to perform straight line fitting to obtain the first boundary line in the edge-grabbing area.

[0017] In the above scheme, the grayscale change between the pixel point and its adjacent pixel points meets the boundary grayscale change requirements, indicating that the grayscale difference between the pixel point and its adjacent pixel points is significant, and the partition where the pixel point is located is different from the partition where the adjacent pixel point is located. The pixel point is determined to be the boundary point of the two partitions in the edge-grabbing area.

[0018] In some embodiments, the first boundary lines in each edge-grabbing area are used to determine width information related to the pole piece, including: determining the partitions that each first boundary line is used to divide; obtaining the distance between the two first boundary lines corresponding to each target partition as the width information of each target partition, wherein the target partition is any partition on the pole piece, or a plurality of consecutive adjacent partitions spliced ​​together.

[0019] In the above solution, the target partition is located between the two boundary lines corresponding to the target partition. Therefore, the distance between the two first boundary lines corresponding to the target partition is the width of the target partition.

[0020] In some embodiments, determining the partitions that each first boundary line is used to divide includes: determining the partitions that each first boundary line is used to divide based on the grayscale information on both sides of each first boundary line; extracting the boundary line partition information of each edge grabbing area from the preset edge grabbing area information, the boundary line partition information including the partition identifier, partition name or partition sorting information of the partition that the first boundary line in the edge grabbing area is used to divide, the partition sorting information indicates the sorting of the partition that the first boundary line is used to divide among the multiple partitions in the width direction of the pole piece; and, using the boundary line partition information of each edge grabbing area, determining the partition that the first boundary line in each edge grabbing area is used to divide.

[0021] In the above scheme, since there will be partitions of the same type in the pole piece, the partition divided by the first boundary line can be determined according to the grayscale information on both sides of the first boundary line, but it is impossible to determine whether the partitions of the same type divided by other first boundary lines are the same partition as the partition used to divide itself. Through the boundary line partition information, the relevant information of the partitions divided by the first boundary line in each edge-grabbing area can be determined, so that the two boundary lines corresponding to each partition can be determined.

[0022] In some embodiments, the width information includes coating-related width information that can characterize the position and / or width of the coating area of ​​the two coating surfaces of the electrode; after using the first boundary line in each grabbing area to determine the width information related to the electrode, the electrode detection method also includes: using the coating-related width information to determine the coating misalignment information, the coating misalignment information characterizing the misalignment of the coating area; based on the coating misalignment information, using a correction mechanism to correct the coating mechanism of the two coating surfaces and at least one of the electrode, so that after correction, the coating areas of the two coating surfaces are aligned and / or are both located at the standard coating position in the coating surface.

[0023] In the above scheme, according to the misalignment of the coating area on the coating surface of the electrode, timely correction will be carried out to align the coating areas of the two coating surfaces of the electrode and both are located at the standard coating position on the coating surface, thereby ensuring the quality of the electrode, thereby ensuring the capacity consistency, safety and reliability of the battery cell manufactured based on the electrode in the future. In addition, the misalignment of the coating areas of the two coating surfaces of the electrode is automatically determined based on the coating image, and the correction based on the misalignment of the coating areas of the two coating surfaces is also automatically performed, all without the need for manual operation. That is, the misalignment of the coating area on the coating surface can be determined in a timely and accurate manner, and correction can be carried out in a timely and accurate manner based on the misalignment of the coating areas of the two coating surfaces. The response to the electrode coating correction is fast, efficient, and accurate, and the burden on the staff is reduced.

[0024] In some embodiments, the pole piece detection method further includes: determining a quality detection area in the image to be detected, the quality detection area including one or more partitions in the width direction of the pole piece; performing quality detection on the quality detection area to obtain a quality detection result of the quality detection area.

[0025] In the above solution, the quality of the electrode can be automatically detected to determine whether there is any abnormality in the electrode in time, thereby avoiding subsequent batch scrapping of the electrode.

[0026] In some embodiments, the grayscale values ​​of each partition of the electrode in the collected image belong to different grayscale intervals; determining the quality detection area in the image to be detected includes: finding the first pixel point whose grayscale value belongs to the target grayscale interval from the image to be detected; obtaining the connected domain formed by the first pixel point as the quality detection area; and / or performing quality detection on the quality detection area to obtain the quality detection result of the quality detection area, including: using the grayscale distribution in the quality detection area to determine whether there are defects in the quality detection area.

[0027] In the above scheme, since the grayscale values ​​of different types of partitions of the electrode (such as coated partitions, uncoated partitions, ceramic partitions, etc.) in the collected image are different, the grayscale values ​​of the same type of partitions in the collected image are basically the same, or in other words, the grayscale values ​​of the same type of partitions in the collected image will belong to their corresponding grayscale intervals, and the grayscale intervals corresponding to different partitions are different. Therefore, the grayscale values ​​of the pixels in the image to be tested can be used to determine the areas in the image to be tested that belong to the various partitions, thereby determining the required quality inspection area.

[0028] In some embodiments, the quality inspection area includes a ceramic partition and a coating partition, and the defect includes metal leakage in the ceramic partition or the coating partition; and / or, the grayscale distribution in the quality inspection area is used to determine whether there is a defect in the quality inspection area, including: finding a number of second pixel points whose grayscale values ​​do not belong to the target grayscale range from the quality inspection area; using the number of second pixel points, determining at least one suspected defect area; in response to the suspected defect area meeting the preset size requirement, determining that the suspected defect area has a defect, the preset size requirement includes at least one of the area meeting the preset area condition and the width meeting the preset width condition.

[0029] In the above scheme, quality inspection is performed on the ceramic partition and coating partition of the electrode to determine whether there is metal leakage in the ceramic partition and coating partition, and to promptly determine whether there are defects in the electrode during the coating process to avoid subsequent coating batch scrapping; and / or, when the suspected defective area meets the preset size requirements, the suspected defective area is regarded as the defective area in the quality inspection area, rather than all determined suspected defective areas being regarded as defective areas in the quality inspection area, thereby improving the accuracy of quality inspection.

[0030] In some embodiments, obtaining an image to be detected obtained by capturing the pole piece includes: obtaining at least two initial images of the pole piece captured by at least two image capture devices corresponding to the same capture moment, and the multiple image capture devices are arranged along the width direction of the pole piece; determining the overlapping area in the at least two initial images; removing the overlapping area of ​​the at least two initial images, and splicing the at least two initial images after removal to obtain the image to be detected; and / or, before determining at least one edge-grabbing area in the image to be detected according to preset edge-grabbing area information, the pole piece detection method also includes: in response to the image to be detected being an abnormal image, discarding the image to be detected; and / or, the image to be detected is obtained by splicing at least two initial images captured by at least two image capture devices corresponding to the same capture moment, and before obtaining the image to be detected captured by the pole piece, the pole piece detection method also includes: in response to the presence of abnormal images in the at least two initial images, discarding the at least two initial images.

[0031] In the above scheme, the image to be detected is generated by splicing initial images captured by at least two image acquisition devices, so that the shooting field of view of the image acquisition device is enlarged and can be suitable for image capture of wide-width pole pieces; and / or, abnormal images to be detected are not detected, thereby reducing resource consumption; and / or, abnormal initial images are not spliced ​​to generate the image to be detected, thereby reducing resource consumption.

[0032] A second aspect of the present application provides a visual inspection system, which includes at least one image acquisition device, a processing device and a host computer; the at least one image acquisition device is used to acquire images of the pole piece; the processing device is communicatively connected to the at least one image acquisition device, and is used to use the image acquired by the at least one image acquisition device to detect the pole piece and obtain a detection result of the pole piece, wherein the detection result includes width information related to the pole piece, and the width information is determined using a first boundary line detected in at least one edge-grabbing area of ​​the image; the host computer is communicatively connected to the processing device, and is used to display the image acquired by the image acquisition device, and / or prompt the detection result.

[0033] In the above solution, therefore, the processing device can be used to detect the pole piece using the image captured by at least one image capture device, that is, the processing device of the visual detection system can realize automatic detection of the pole piece.

[0034] Furthermore, the above scheme can also be provided with a monitoring device, which can be used to display the images collected by the image acquisition device so that relevant personnel can promptly know the coating status of the electrode; or the monitoring device can be used to prompt the detection results so that relevant personnel can promptly know the detection status of the electrode, so that when the electrode detection is abnormal, corresponding processing can be carried out in time to prevent the coating batch from being scrapped. Therefore, the visual inspection system can also integrate the electrode detection function and the related information display function into one, which can realize both automatic detection of the electrode and image display and / or detection result prompts.

[0035] In some embodiments, the image acquisition device is a first type of acquisition device, and the system further includes a light source for providing shooting light for the first type of acquisition device, the light source and the first type of acquisition device are respectively located on both sides of the target normal, and the target normal is the normal of the tangent between the electrode piece and the roller used to transport the electrode piece; wherein, there is a first distance between the intersection of the optical axis of the first type of acquisition device and the acquisition surface and the target tangent point, the acquisition surface is the side of the electrode piece facing the first type of acquisition device, and the target tangent point is the tangent point between the electrode piece and the roller used to transport the electrode piece, and the first distance can make the incident amount of the reflected light of the light source from the roller incident on the first type of acquisition device lower than a preset threshold; and / or, the second distance between the first type of acquisition device and the acquisition surface is related to the focal length of the first type of acquisition device; and / or, there is a first angle between the irradiated light of the light source and the target normal, and there is a second angle between the optical axis of the first type of acquisition device and the target normal, and the size of at least one of the first angle and the second angle can make the illumination intensity of the shooting area of ​​the first type of acquisition device meet the requirements; and / or, there is a third distance between the light source and the acquisition surface.

[0036] In the above scheme, the intersection point between the optical axis of the first type of acquisition device and the acquisition surface and the target tangent point are set according to the first distance, which can make the incident amount of the reflected light of the roller on the light source to the first type of acquisition device lower than the preset threshold value, thereby improving the quality of the image collected on the acquisition surface; and / or, the second distance between the first type of acquisition device and the acquisition surface is set to be related to the focal length of the first type of acquisition device, which can make the first type of acquisition device and the acquisition surface be in a suitable position, so that the first type of acquisition device can capture a bright image with uniform image quality and no distortion; and / or, by setting the irradiation light of the light source to form a first angle with the target normal and the optical axis of the first type of acquisition device to form a second angle with the target normal, the light intensity of the light source on the acquisition surface can be the strongest and the power consumption can be the least.

[0037] In some embodiments, the image acquisition device is a second-type acquisition device, the second-type acquisition device is connected to multiple acquisition cards corresponding to the second-type acquisition device, and the multiple acquisition cards corresponding to the second-type acquisition device are connected to the processing device; wherein, the multiple acquisition cards corresponding to the second-type acquisition device are connected to each other through an inter-board synchronization line, and the system's encoder transmits an acquisition trigger signal to one of the acquisition cards, and one of the acquisition cards is synchronized with the remaining acquisition cards corresponding to the second-type acquisition device through the inter-board synchronization line to trigger the second-type acquisition device to perform image acquisition.

[0038] In the above solution, the second type of acquisition device can be triggered to perform image acquisition through the acquisition card, and the triggering control of the second type of acquisition device is more flexible and convenient.

[0039] In some embodiments, the image acquisition device is a second-type acquisition device, the second-type acquisition device is connected to multiple acquisition cards corresponding to the second-type acquisition device, and the multiple acquisition cards corresponding to the second-type acquisition device are connected to the processing device; wherein, the system also includes a signal distributor connected to the encoder, and the acquisition trigger signal emitted by the encoder outputs multiple acquisition trigger signals through the signal distributor to be transmitted to each acquisition card respectively to trigger the second-type acquisition device to perform image acquisition.

[0040] In the above solution, the acquisition cards of multiple second-type acquisition devices can be triggered simultaneously through the signal distributor connected to the encoder.

[0041] In some embodiments, the second type of acquisition device is a macro camera; and / or, there is a third distance between the second type of acquisition device and the acquisition surface, and the acquisition surface is the side of the pole piece facing the first type of acquisition device.

[0042] In the above solution, the macro camera can capture high-resolution images at high speed over a wide range, and can capture images at close range, saving space; and / or, can flexibly set the distance between the second type of acquisition device and the acquisition surface.

[0043] In some embodiments, at least one image acquisition device includes at least one device group, each device group includes at least one image acquisition device, and different device groups are used to acquire images from different surfaces of the pole piece.

[0044] In the above solution, by setting up multiple groups of devices, images of different sides of the electrode can be collected simultaneously, so that relevant conditions such as the coating on the front and back sides of the electrode can be known in a timely manner.

[0045] In some embodiments, at least one device group includes a first device group and a second device group, and the processing device includes a main processing device and a slave processing device; the main processing device is connected to the first device group, and is used to detect the image collected by the first device group to obtain a first detection result; the slave processing device is connected to the second device group, and is used to detect the image collected by the second device group to obtain a second detection result, and send at least one of the image collected by the second device group and the second detection result to the main processing device; the main processing device is connected to the monitoring equipment, and is also used to send the images collected by the first device group and the second device group to the monitoring equipment, and / or, prompt the first detection result and the second detection result.

[0046] In the above scheme, when the visual inspection system includes two device groups, one processing device cannot support the normal operation of the two device groups at the same time, so a master-slave processing device is set up, and the master-slave processing device is connected to one device group respectively to ensure its normal operation.

[0047] In some embodiments, the image acquisition device is a first type of acquisition device, and the system also includes two light source modules, each light source module includes a light source and a light source controller connected to each other, and the light source controllers of the two light source modules are respectively connected to the main processing device and the slave processing device, so that the corresponding connected processing device instructs the light source controller to control the operation of the corresponding light source; and / or, the main processing device and the slave processing device are connected through a network.

[0048] In the above solution, the illumination parameters of the light source can be flexibly controlled by the processing device; and / or, the network connection between the main processing device and the slave processing device can be connected for long-distance communication and is less affected by the installation location area.

[0049] In some embodiments, the host computer includes at least one, and the at least one host computer is located at a preset position of the coating system for coating the electrode.

[0050] In the above solution, the number of monitoring devices and the specific locations of the monitoring devices can be flexibly set.

[0051] The third aspect of the present application provides a coating system, which includes an unwinding mechanism for unwinding the electrode; a first coating mechanism for coating the first coating surface of the unwound electrode; a second coating mechanism, which is arranged after the first coating mechanism, for coating the second coating surface of the electrode; a drying mechanism for drying the electrode after being coated by the first coating mechanism and the second coating mechanism; a winding mechanism for winding the dried electrode; a visual inspection system, the visual inspection system includes at least one image acquisition device and a processing device, the image acquisition device is used to acquire an image of the electrode to obtain an image to be detected; the processing device is used to determine at least one edge-grabbing area in the image to be detected according to preset edge-grabbing area information, the preset edge-grabbing area information including position information and / or size information of the edge-grabbing area; perform boundary detection on each edge-grabbing area to obtain a first boundary line in each edge-grabbing area, the first boundary line is used to divide the electrode arrangement in the width direction into different partitions; and use the first boundary line in each edge-grabbing area to determine width information related to the electrode.

[0052] In some embodiments, the visual inspection system also includes a first image acquisition device and a second image acquisition device, the first image acquisition device and the second image acquisition device are arranged behind the second coating mechanism, and the first image acquisition device is arranged on one side of the first coating surface, and the second image acquisition device is arranged on one side of the second coating surface.

[0053] In some embodiments, the visual inspection system further includes a correction mechanism for correcting the coating surface of the pole piece.

[0054] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application.

Brief Description of the Drawings

[0055] 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.

[0056] FIG1 is a flow chart of an embodiment of a pole piece detection method provided by the present application;

[0057] FIG2 is a schematic diagram of an embodiment of an image to be detected provided by the present application;

[0058] FIG3 is a schematic diagram of another embodiment of an image to be detected provided by the present application;

[0059] FIG4 is a schematic diagram of the layout of the image acquisition device provided by the present application;

[0060] FIG5 is a schematic diagram of the arrangement of two image acquisition devices provided by the present application;

[0061] FIG6 is a schematic structural diagram of an embodiment of a coating system provided by the present application;

[0062] FIG7 is a schematic diagram of an embodiment of a gripping area provided by the present application;

[0063] FIG8 is a flow chart of another embodiment of a pole piece detection method provided by the present application;

[0064] FIG9 is a flow chart of another embodiment of a pole piece detection method provided by the present application;

[0065] FIG10 is a schematic diagram of a flow chart of an embodiment of step S91 shown in FIG9 ;

[0066] FIG11 is a flow chart of an embodiment of the present application providing a method for determining whether a quality inspection area has defects by using the grayscale distribution of the quality inspection area;

[0067] FIG12 is a schematic diagram of a flow chart of an embodiment of step S11 shown in FIG1 ;

[0068] FIG13 is a flow chart of an embodiment of generating preset edge-grabbing area information provided by the present application;

[0069] FIG14 is a schematic diagram of an embodiment of a boundary detection area provided by the present application;

[0070] FIG15 is a schematic diagram of a flow chart of an embodiment of step S13 shown in FIG1 ;

[0071] FIG16 is a schematic diagram of an embodiment of a caliper tool provided by the present application;

[0072] FIG17 is a schematic diagram of a flow chart of an embodiment of step S14 shown in FIG1 ;

[0073] FIG18 is a schematic diagram of a flow chart of an embodiment of step S171 shown in FIG17 ;

[0074] FIG19 is a schematic diagram of the electrical topology of an embodiment of a visual inspection system provided by the present application;

[0075] FIG20 is a schematic diagram of the electrical topology of another embodiment of the visual inspection system provided by the present application;

[0076] FIG21 is a schematic diagram of an embodiment of a shooting point of an image acquisition device provided by the present application;

[0077] FIG22 is a schematic diagram of the installation of an image acquisition device according to an embodiment of the present application;

[0078] FIG23 is a schematic diagram of an embodiment of electrical wiring of a macro camera provided by the present application;

[0079] FIG24 is a schematic diagram of an embodiment of macro camera imaging provided in the present application. [Specific implementation method]

[0080] The following describes the embodiments of the present application in detail with reference to the accompanying drawings.

[0081] In the following description, for the purpose of explanation rather than limitation, specific details such as specific system structures, interfaces, and technologies are provided to facilitate a thorough understanding of the present application.

[0082] The term "and / or" in this article is simply a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects are in an "or" relationship. In addition, "many" in this article means two or more than two. In addition, the term "at least one" in this article means any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can mean including any one or more elements selected from the set consisting of A, B, and C.

[0083] Please refer to FIG1 , which is a flow chart of an embodiment of the electrode detection method provided by the present application. It should be noted that the embodiments of the present application are not limited to the flow sequence shown in FIG1 if substantially the same results are achieved. As shown in FIG1 , the present embodiment includes:

[0084] Step S11: obtaining the image to be detected acquired by the electrode piece.

[0085] The method of this embodiment is used to automatically detect width information related to the electrode, improve the detection accuracy and efficiency of the width information related to the electrode, and greatly reduce the width measurement error, thereby ensuring that the electrode is subsequently laser-cut out to a width that meets the process requirements based on the detected width information, preventing the cutter from cutting off-center, and further ensuring the safety and capacity consistency of batteries made based on electrode pieces with a width that meets the process requirements.

[0086] In this embodiment, an image to be detected is obtained by capturing the electrode. When the electrode is an aluminum foil current collector, the positive electrode material (such as LEP, NCM, etc.) is coated on the aluminum foil current collector, while when the electrode is a copper foil current collector, the negative electrode material (such as graphite, LTO, etc.) is coated on the copper foil current collector. Copper foil, as the negative electrode current collector of the battery, acts as a carrier of the negative electrode active material and also serves as a negative electrode electron collector and conductor. Its function is to collect the current generated by the battery active material to generate a larger output current. Aluminum foil, as the positive electrode current collector of the battery, acts as a carrier of the positive electrode active material. Batteries using aluminum foil current collectors have strong charge and discharge capabilities, are not easily corroded by the electrolyte, and can increase adhesion with the positive electrode active material.

[0087] For example, as shown in Figures 2 and 3, Figure 2 is a schematic diagram of an embodiment of the image to be detected provided by the present application, and Figure 3 is a schematic diagram of another embodiment of the image to be detected provided by the present application; the image to be detected shown in Figure 2 is obtained by collecting the anode electrode, and the anode electrode includes roller partitions (areas 1 and 5 in Figure 2), uncoated partitions (areas 2 and 4 in Figure 2), and coated partitions (area 3 in Figure 2) arranged along the width direction of the electrode (AB direction and BA direction in Figure 2); the image to be detected shown in Figure 3 is obtained by collecting the cathode electrode, and the cathode electrode includes roller partitions (areas 1 and 2 in Figure 3), uncoated partitions (areas 2 and 6 in Figure 3), ceramic partitions (areas 3 and 5 in Figure 3), and coated partitions (area 4 in Figure 3) arranged along the width direction of the electrode (CD direction and DC direction in Figure 3).

[0088] In one embodiment, an image acquisition device can be used to capture images of the electrode piece in real time to obtain an image to be detected. The image acquisition device can be a CCD (Charge Coupled Device) camera, etc., which is not limited here. Of course, in other embodiments, the image to be detected can also be obtained from cloud storage or local storage, which is not specifically limited here.

[0089] Because a single image acquisition device has a limited field of view, the size of the electrode piece that can be captured is limited; that is, for wide electrode pieces, a single image acquisition device cannot capture an image to be detected that includes the entire electrode piece. Therefore, in one embodiment, at least two image acquisition devices arranged along the width of the electrode piece are used to simultaneously capture images of the electrode piece to obtain an image to be detected captured of the electrode piece. Of course, in other embodiments, for narrow electrode pieces, a single image acquisition device can also be used to capture images of the electrode piece to obtain an image to be detected captured of the electrode piece.

[0090] Among them, the number of image acquisition devices that capture images of the electrode at the same acquisition moment is not limited and can be specifically set according to actual use needs. For example, as shown in Figures 4 and 5, Figure 4 is a schematic diagram of the layout of the image acquisition device provided by this application, and Figure 5 is a schematic diagram of the arrangement of two image acquisition devices provided by this application; the width of the wide electrode is 1500mm-1600mm, and the field of view of a single image acquisition device is 775mm. Therefore, two image acquisition devices arranged along the width direction of the electrode are used to capture images of the electrode at the same time, thereby obtaining an image to be detected of the electrode, and the image to be detected includes the complete electrode. For another example, the width of a narrow electrode is about 700mm, and a single image acquisition device can be set to capture an image to be detected that includes the complete electrode.

[0091] In a specific embodiment, as shown in Figure 6, Figure 6 is a structural schematic diagram of an embodiment of a coating system provided in the present application, and the coating system 60 includes a unwinding mechanism 61, an A-side die head 62 (first coating mechanism) corresponding to one coating surface (first coating surface), a lower oven 63 corresponding to one coating surface, a B-side die head 64 (second coating mechanism) corresponding to another coating surface (second coating surface), an upper oven 65 corresponding to another coating surface (second coating surface), two image acquisition devices 91, a winding mechanism 66, a roller 67 and a light source 68. The electrode is used to be wound on the unwinding mechanism 61, and passes through the A-side die 62, the lower oven 63, the B-side die 64, and the upper oven 65 in sequence and then is wound by the winding mechanism 66. The A-side die 62 is used to coat the first coating surface (one coating surface) of the electrode to coat the positive or negative electrode active material on the first coating surface of the electrode. The lower oven 63 is used to dry the wet film after coating the first coating surface. The B-side die 64 is used to coat the second coating surface (the other coating surface) of the electrode to coat the positive or negative electrode active material on the second coating surface of the electrode. The upper oven 65 is used to dry the wet film after coating the second coating surface, so that the electrode in the dry film state is output from the upper oven, which is convenient for the winding mechanism 66 to wind it up, thereby facilitating the subsequent battery cell winding operation.

[0092] After the electrode is output from the second drying mechanism, it passes through two image acquisition devices. One image acquisition device captures an image of the first coated surface of the electrode, and the other image acquisition device captures an image of the second coated surface of the electrode, thereby obtaining the images to be tested corresponding to each coated surface of the electrode. In other words, by adding two image acquisition devices to the coating system, the electrode coating and correction are integrated, and the coating images of the two opposing coated surfaces of the electrode can be captured in a timely manner after the coating is completed and before the winding.

[0093] In addition, two image acquisition devices can be set on both sides, that is, after the electrode is output from the second drying mechanism, it will pass through the two image acquisition devices located above and the two image acquisition devices located below (the two image acquisition devices located on the same side are arranged along the width direction of the electrode). The two image acquisition devices simultaneously capture images of the first coated surface of the electrode, and the two image acquisition devices simultaneously capture images of the second coated surface of the electrode, thereby obtaining images to be detected corresponding to each coated surface.

[0094] In one specific embodiment, the image to be detected is generated by stitching together at least two initial images acquired at the same time by at least two image acquisition devices. Before acquiring the image to be detected acquired by the polarimetric piece, in response to the presence of abnormal images in the at least two initial images, the at least two initial images are discarded. In other words, abnormal initial images are not stitched together to generate the image to be detected, thereby reducing resource consumption. There are no restrictions on the type of abnormal images; for example, abnormal images may include those with low clarity or those that do not meet the required size.

[0095] Step S12: determining at least one edge-grabbing area in the image to be detected according to the preset edge-grabbing area information.

[0096] In this embodiment, at least one edge-grabbing region is determined in the image to be inspected based on preset edge-grabbing region information. The preset edge-grabbing region information includes position information and / or size information of the edge-grabbing region. Therefore, based on the preset edge-grabbing region information, the edge-grabbing region in the image to be inspected can be quickly located, thereby enabling subsequent rapid determination of electrode width information, thereby improving electrode inspection efficiency.

[0097] Among them, the position information of the edge-grabbing area included in the preset edge-grabbing area information is not limited and can be specifically set according to actual use needs. For example, the position information of the edge-grabbing area included in the preset edge-grabbing area information is the center of the edge-grabbing area; for another example, the edge-grabbing area is rectangular, and the position information of the edge-grabbing area included in the preset edge-grabbing area information is the position coordinates of the upper left corner vertex, the position coordinates of the lower right corner vertex, etc. of the edge-grabbing area. In addition, the size information of the edge-grabbing area included in the preset edge-grabbing area information is not limited. For example, the edge-grabbing area included in the preset edge-grabbing area information is a square area with a side length of 2mm. For another example, the edge-grabbing area included in the preset edge-grabbing area information is a rectangular area with a length of 2mm and a width of 3mm. For another example, the edge-grabbing area included in the preset edge-grabbing area information is a circular area with a radius of 2mm.

[0098] For example, as shown in Figure 7, Figure 7 is a schematic diagram of an embodiment of the edge-grabbing area provided by the present application. According to the preset edge-grabbing area information, 6 edge-grabbing areas (A, B, C, D, E, F) are determined in the image to be detected, and the 6 edge-grabbing areas are square areas.

[0099] In one embodiment, when the electrode piece is an anode electrode piece, at least four edge-grabbing regions are determined in the image to be inspected based on the preset edge-grabbing region information. Alternatively, when the electrode piece is a cathode electrode piece, at least six edge-grabbing regions are determined in the image to be inspected based on the preset edge-grabbing region information. For example, as shown in FIG7 , FIG7 illustrates a cathode electrode piece. Based on the preset edge-grabbing region information, six edge-grabbing regions are determined in the image to be inspected.

[0100] In one embodiment, the preset edge-grabbing region information is automatically generated before determining at least one edge-grabbing region in the image to be detected. This is more efficient. Of course, in other embodiments, the preset edge-grabbing region information may also be manually set by a user, which is not specifically limited here.

[0101] In one embodiment, before determining at least one edge-grabbing region in an image to be inspected, the image to be inspected is discarded in response to being an abnormal image. In other words, abnormal images to be inspected are not inspected, thus reducing resource consumption. There are no restrictions on the type of abnormal images; for example, abnormal images may include images with low clarity, images of unsuitable size, or images with insufficient number of partitions.

[0102] Step S13: performing boundary detection on each edge-grabbing area to obtain a first boundary line in each edge-grabbing area.

[0103] In this embodiment, boundary detection is performed on each edge-grabbing area to obtain a first boundary line in each edge-grabbing area; wherein the first boundary line is used to divide the electrode into different zones arranged in the width direction.

[0104] In one embodiment, the boundary detection of each edge-grabbing area is performed in multiple threads, that is, boundary detection is performed on multiple edge-grabbing areas in the image to be detected simultaneously, thereby improving the efficiency of obtaining the first boundary line in each edge-grabbing area.

[0105] In one embodiment, the boundary detection of each edge-grabbing region is performed using a separate thread. That is, the boundary detection of each edge-grabbing region corresponds to one thread, i.e., the first boundary line of each edge-grabbing region in the image to be detected is captured simultaneously, thereby speeding up the calculation and reducing the processing time of a single image to be detected.

[0106] Because different sections of the electrode sheet have different grayscale values, or in other words, because different sections of the electrode sheet belong to different grayscale intervals, if the grayscale significance on either side of a line in the edge-grabbing area is different, it indicates that the left and right sides of the line belong to different sections of the electrode sheet, and the line is the boundary between the two sections in the edge-grabbing area. Therefore, in one embodiment, the first boundary line in the edge-grabbing area can be determined based on the grayscale distribution in the edge-grabbing area.

[0107] Step S14: using the first boundary line in each edge-grabbing area, determine width information related to the electrode piece.

[0108] In this embodiment, the first boundary lines in each edge gripping area are used to determine the width information related to the electrode. The distance between two first boundary lines corresponding to a partition is used to determine the width of the partition corresponding to the two first boundary lines.

[0109] Optionally, the width information related to the pole piece includes but is not limited to the width of the coating partition, the width of the ceramic partition, the width of the pole piece, the width of the uncoated partition, and the width of the roller partition.

[0110] In the above embodiment, at least one edge-grabbing region is determined in the image to be inspected based on the preset edge-grabbing region information. Boundary detection is performed on each edge-grabbing region to obtain a first boundary line within each edge-grabbing region. Width information associated with the electrode piece is then determined using the first boundary line within each edge-grabbing region. Thus, automatic detection of the electrode piece can be achieved.

[0111] Furthermore, the above scheme can also use the preset edge-grabbing area to determine the width information related to the pole piece, thereby realizing automatic detection of the width information related to the pole piece; in addition, the preset edge-grabbing area does not require user setting, thereby improving the detection efficiency of the width information related to the pole piece.

[0112] In one embodiment, as shown in FIG8 , FIG8 is a flow chart of another embodiment of the electrode piece detection method provided by the present application, wherein the width information includes coating-related width information that can characterize the position and / or width of the coating area of ​​the two coating surfaces of the electrode piece; after the width information related to the electrode piece is determined using the first boundary line in each gripping area, the electrode piece coating correction is also performed, specifically including the following steps:

[0113] Step S81: Determine coating misalignment information using coating-related width information.

[0114] In this embodiment, the coating-related width information is used to determine the coating misalignment information; wherein the coating misalignment information characterizes the misalignment of the coating area. Since the width information includes the position and / or width of the coating area that can characterize the two coating surfaces of the electrode, the misalignment between the coating areas in the two coating surfaces (i.e., whether the coating areas of the two coating surfaces are aligned) can be determined based on the coating-related width information; or, the misalignment between the coating area in the coating surface and the coating standard position in the coating surface (i.e., whether the coating area in the coating surface is located at the coating standard position in the coating surface) can be determined based on the coating-related width information.

[0115] In one embodiment, the coating misalignment information includes second misalignment information, which indicates the misalignment between the coating areas of the two coating surfaces. Subsequently, regional deviation correction of the coating areas of the two coating surfaces is performed based on the second misalignment information, so that the coating areas of the two coating surfaces are aligned after the deviation correction.

[0116] In other embodiments, the coating misalignment information includes first misalignment information and second misalignment information, wherein the first misalignment information characterizes the misalignment between a coating area of ​​a coating surface and a marked coating position of the coating surface, and the second misalignment information characterizes the misalignment between the coating areas of two coating surfaces. Subsequently, the position of the coating area on the coating surface will be corrected based on the first misalignment information, so that the coating surface corresponding to the first misalignment information is located at the standard coating position in the coating surface after correction; similarly, regional correction of the coating areas of the two coating surfaces will be performed based on the second misalignment information, so that the coating areas of the two coating surfaces are aligned after correction; and since the coating surface corresponding to the first misalignment information is located at the standard coating position in the coating surface after correction, the coating area in the other coating surface that is aligned with the coating surface after correction is naturally also located at the standard coating position in the corresponding coating surface. Therefore, subsequent correction based on the first misalignment information and the second misalignment information can align the coating areas of the two coating surfaces after correction and both are located at the standard coating position on the coating surface.

[0117] It should be noted that the two coating surfaces are the front and back coating surfaces of the same electrode, so the standard coating positions corresponding to the coating surfaces are the same.

[0118] Since the standard coating positions of the two coating surfaces of the same electrode are the same, when the coating areas on the two coating surfaces are both located at the standard coating positions in the corresponding coating surfaces, the coating areas on the two coating surfaces must be aligned and both located at the standard coating positions in the coating surfaces. Therefore, in other embodiments, the coating misalignment information includes two first misalignment information, one first misalignment information characterizing the misalignment between the coating area of ​​one coating surface and the standard coating position of the coating surface, and the other first misalignment information characterizing the misalignment between the coating area of ​​another coating surface and the standard coating position of the coating surface. Subsequently, the position of a coating area on the corresponding coating surface will be corrected based on the first misalignment information, so that the coating area corresponding to the first misalignment information will be located at the standard coating position in the corresponding coating surface after correction; similarly, the position of another coating area on the corresponding coating surface will be corrected based on the other first misalignment information, so that the coating area corresponding to the first misalignment information will be located at the standard coating position in the corresponding coating surface after correction. Therefore, the subsequent deviation correction based on the two first misalignment information can ensure that the coating areas of the two coating surfaces are aligned after the deviation correction and are both located at the standard coating positions on the coating surfaces.

[0119] Step S82: Based on the coating misalignment information, use a correction mechanism to correct at least one of the coating mechanisms and pole pieces of the two coating surfaces so that the coating areas of the two coating surfaces are aligned and / or are both located at the standard coating positions in the coating surfaces after correction.

[0120] In this embodiment, based on the coating misalignment information, a correction mechanism is used to correct the coating mechanisms of the two coating surfaces and at least one of the electrode pieces, so that after the correction, the coating areas of the two coating surfaces are aligned and / or both are located at the standard coating position on the coating surface. In other words, correction will be performed in a timely manner based on the misalignment of the coating areas on the coating surface of the electrode piece, so that the coating areas of the two coating surfaces of the electrode piece are aligned and both are located at the standard coating position on the coating surface, thereby ensuring the quality of the electrode piece and thus ensuring the capacity consistency, safety and reliability of the battery cell subsequently manufactured based on the electrode piece. In addition, the misalignment of the coating areas of the two coated surfaces of the electrode is automatically determined based on the coating image, and the correction based on the misalignment of the coating areas of the two coated surfaces is also automatically performed, without the need for manual operation; that is, the electrode coating correction method provided in the present application can timely and accurately determine the misalignment of the coating areas on the coating surfaces and can timely and accurately correct the misalignment based on the misalignment of the coating areas of the two coated surfaces, and has a fast response to the electrode coating correction, high efficiency, high correction accuracy, and reduces the burden on staff.

[0121] It should be noted that it is not limited to the need to correct the coating mechanisms of the two coating surfaces so that the coating areas of the two coating surfaces are aligned after correction and are both located in the standard coating positions on the coating surfaces; for example, the coating mechanisms of the two coating surfaces may be corrected separately, or the coating mechanism and electrode of one coating surface may be corrected, or the coating mechanisms and electrode of two coating surfaces may be corrected.

[0122] In addition, the coating areas of the two coating surfaces are aligned and located at the standard coating positions on the coating surfaces after the correction, which means that after the two coating surfaces of the new substrate material strip are subsequently coated by the corresponding coating mechanism, the coating areas of the two coating surfaces are aligned and located at the standard coating positions on the coating surface; that is, the purpose of correcting the coating mechanisms and at least two of the pole pieces of the two coating surfaces is to ensure that the subsequent coating of the pole pieces is not misplaced, and the coating situation of the pole piece corresponding to the coating image can no longer be adjusted.

[0123] In one embodiment, as shown in FIG6 , the coating system further includes a deflection correction mechanism, which can be used to correct the deflection so that the coating areas of the two coating surfaces are aligned and / or both are located at the standard coating position on the coating surface after the deflection correction. In a specific embodiment, the coating system includes a first deflection correction mechanism and a second deflection correction mechanism, the first deflection correction mechanism is arranged between the unwinding mechanism and the first coating mechanism, and the second deflection correction mechanism is arranged between the first drying mechanism and the second coating mechanism. The first deflection correction mechanism can be used to correct the deflection of the first coating mechanism and / or the electrode, and the second deflection correction mechanism can be used to correct the deflection of the second coating mechanism and / or the electrode.

[0124] If there is an abnormality in the electrode piece, it will affect the quality of the battery generated based on the electrode piece, such as causing poor capacitance consistency, low safety, high self-discharge, capacity decay, etc. Therefore, in one embodiment, as shown in Figure 9, Figure 9 is a flow chart of another embodiment of the electrode piece detection method provided by the present application, it is also necessary to detect the quality of the electrode piece to avoid subsequent batch scrapping of the electrode pieces, which specifically includes the following steps:

[0125] Step S91: Determine a quality detection area in the image to be detected.

[0126] In this embodiment, a quality detection area in the image to be detected is determined; wherein the quality detection area includes one or more partitions in the width direction of the pole piece.

[0127] In one embodiment, the quality detection area is all the partitions in the width direction of the electrode piece. Of course, in other embodiments, the quality detection area is part of the partitions in the width direction of the electrode piece, which is not limited here.

[0128] If the coated active material is separated during the drying process of the coated electrode, the battery prepared based on the electrode will have low capacity, unstable internal resistance, low cycle times, and may even form an internal short circuit in the battery. In severe cases, it may cause the battery to catch fire and explode. Therefore, in one embodiment, if it is necessary to detect whether the electrode has metal leakage flaws / defects, the coating partition can be defined as the quality inspection area to reduce the size of the area to be inspected and improve the efficiency of quality inspection. Of course, in other embodiments, if it is necessary to detect whether the electrode has metal leakage flaws / defects, all partitions can also be used as quality inspection areas.

[0129] For example, as shown in Figure 2, taking the detection of whether the electrode has metal leakage flaws / defects as an example: since it is necessary to detect whether the electrode has metal leakage flaws / defects, the coating partition in Figure 2 (area 3 in Figure 2) is used as the quality inspection area. For another example, as shown in Figure 3, taking the detection of whether the electrode has metal leakage flaws / defects as an example: since it is necessary to detect whether the electrode has metal leakage flaws / defects, the coating partition (area 3 in Figure 3) and the ceramic partition (area 2 and area 5 in Figure 3) in Figure 3 are both used as quality inspection areas.

[0130] Since the grayscale values ​​of different partitions of the electrode (such as coated partitions, uncoated partitions, ceramic partitions, etc.) in the collected image are different, the grayscale values ​​of the same partitions in the collected image are basically the same, or in other words, the grayscale values ​​of the same partitions in the collected image will belong to their corresponding grayscale intervals, and the grayscale intervals corresponding to different partitions are different. Therefore, the areas belonging to various partitions in the image to be detected can be determined by the grayscale values ​​of the pixels in the image to be detected, so that the required quality detection area can be determined. Therefore, in one embodiment, as shown in Figure 10, Figure 10 is a flow chart of an embodiment of step S91 shown in Figure 9, and the grayscale values ​​of each partition of the electrode in the collected image to be detected belong to different grayscale intervals, and determining the quality detection area in the image to be detected specifically includes the following sub-steps:

[0131] Step S101: Find the first pixel whose grayscale value belongs to the target grayscale range from the image to be detected.

[0132] In this embodiment, a first pixel point whose grayscale value belongs to a target grayscale range is found from the image to be detected.

[0133] For example, take the grayscale interval of the coated partition as a grayscale value of 40-60 and the grayscale interval of the uncoated partition as a grayscale value greater than 200: if the coated partition needs to be used as the quality inspection area, then the grayscale interval of 40-60 is used as the target grayscale interval, and the first pixel point with a grayscale value between 40-60 is found from the image to be inspected.

[0134] For example, take the grayscale interval of the coated partition as a grayscale value of 20-40, the grayscale interval of the uncoated partition as a grayscale value greater than 220, and the grayscale interval of the ceramic partition as a grayscale value of 110-130: if the coated partition and the ceramic partition are required as quality inspection areas, then the grayscale interval of 20-40 and the grayscale interval of 110-130 are used as target grayscale intervals, and from the image to be inspected, find the first pixel point with a grayscale value between 20-40 and a grayscale value between 110-130.

[0135] Step S102: Obtain a connected region formed by the first pixel point as a quality detection region.

[0136] In this embodiment, the connected domain formed by the first pixel points is obtained as the quality detection area. In other words, the area formed by the first pixel points is used as the quality detection area.

[0137] Step S92: Perform quality inspection on the quality inspection area to obtain a quality inspection result of the quality inspection area.

[0138] In this embodiment, the quality inspection area is subjected to quality inspection to obtain a quality inspection result of the quality inspection area. The quality inspection area is subjected to quality inspection to determine whether there are defects / blemishes in the quality inspection area.

[0139] A quality inspection area corresponds to a partition of the electrode. Therefore, when the partition corresponding to the quality inspection area is of high quality and does not contain defects / blemishes, the grayscale distribution of the quality inspection area is uniform and consistent, without obvious differences. However, when the partition corresponding to the quality inspection area contains defects / blemishes, the grayscale distribution of the defective / blemish part in the quality inspection area will be significantly different from the grayscale distribution of other parts of the quality inspection area. Therefore, in one embodiment, a quality inspection is performed on the quality inspection area to obtain a quality inspection result for the quality inspection area. Specifically, the grayscale distribution in the quality inspection area is used to determine whether there are defects in the quality inspection area. By using the grayscale distribution differences in the quality inspection area, it is possible to accurately and quickly determine whether there are defects in the quality inspection area.

[0140] In one specific embodiment, the quality inspection area includes a ceramic partition and a coating partition, and the defect includes the presence of metal leakage in the ceramic partition or the coating partition. By performing quality inspection on the ceramic partition and the coating partition of the electrode, it is determined whether there is metal leakage in the ceramic partition and the coating partition, and whether there are defects in the electrode during the coating process is determined in time to avoid subsequent coating batch scrapping. In other specific embodiments, the quality inspection area includes a ceramic partition and a coating partition, and the defects may also be the presence of bubbles, particles, pinholes, etc. in the ceramic partition or the coating partition. In other specific embodiments, the quality inspection area includes each partition of the electrode, and the defects may be bends, creases, wrinkles, indentations, cracks, etc. in each partition. In other specific embodiments, the quality inspection area includes the edge partition of the electrode, and the defects may be the presence of material dropouts, notches, cracks, etc. in each edge partition.

[0141] In one embodiment, as shown in FIG11 , FIG11 is a flow chart of an embodiment of determining whether a quality inspection area has defects using the grayscale distribution of the quality inspection area provided by the present application. Determining whether a quality inspection area has defects using the grayscale distribution in the quality inspection area specifically includes the following sub-steps:

[0142] Step S111: searching for a plurality of second pixel points whose grayscale values ​​do not belong to the target grayscale range in the quality detection area.

[0143] In this embodiment, a plurality of second pixel points whose grayscale values ​​do not belong to the target grayscale interval are found from the quality detection area.

[0144] For example, taking the target grayscale interval as the grayscale interval corresponding to the coating partition and the grayscale interval of the coating partition as the grayscale value 40-60 as an example: from the image to be detected, find several second pixel points whose grayscale values ​​are not between 40-60.

[0145] For another example, taking the target grayscale interval as the grayscale interval corresponding to the coating partition and the grayscale interval corresponding to the ceramic partition, the grayscale interval of the coating partition is a grayscale value of 20-40, and the grayscale interval of the ceramic partition is a grayscale value of 110-130: from the image to be detected, find several second pixel points whose grayscale values ​​are not between 40-60 and not between 110-130.

[0146] Step S112: using a plurality of second pixel points to determine at least one suspected defect area.

[0147] In this embodiment, at least one suspected defect region is determined using a plurality of second pixel points, that is, a region formed by a plurality of second pixel points is used as a suspected defect region.

[0148] Step S113: In response to the suspected defect area meeting the preset size requirement, determining that a defect exists in the suspected defect area.

[0149] In this embodiment, in response to a suspected defect region meeting a preset size requirement, a suspected defect region is determined to be defective. That is, only when a suspected defect region meets the preset size requirement is the suspected defect region considered a defect region in the quality inspection area, rather than all determined suspected defect regions being considered defect regions in the quality inspection area, thereby improving the accuracy of quality inspection.

[0150] The preset size includes at least one of an area meeting a preset area condition and a width meeting a preset width condition. The preset area condition and the preset width condition are not limited and can be set according to actual use needs.

[0151] For example, taking the defect as metal leakage in the coating partition, the target grayscale interval as the grayscale interval corresponding to the coating partition, the grayscale interval of the coating partition as a grayscale value of 40-60, and the grayscale interval corresponding to the metal leakage as a grayscale value of 170-255 as an example: find out a number of second pixel points whose grayscale values ​​are not between 40-60 from the quality inspection area, and find out a number of second pixel points whose grayscale values ​​are between 170-255 from the quality inspection area; use the number of second pixel points to determine the suspected defect area A and the suspected defect area B; because the suspected defect area A meets the preset size requirements and the suspected defect area B does not meet the preset size requirements, it is determined that there is metal leakage in the suspected defect area A and there is no metal leakage in the suspected defect area B.

[0152] Please refer to FIG12, which is a flow chart of an embodiment of step S11 shown in FIG1. ​​It should be noted that the embodiments of the present application are not limited to the flow sequence shown in FIG12 if substantially the same results are achieved. As shown in FIG12, this embodiment includes:

[0153] Step S121: obtaining at least two initial images of the electrode piece acquired by at least two image acquisition devices at the same acquisition time.

[0154] In this embodiment, at least two initial images of the pole piece are acquired by at least two image acquisition devices corresponding to the same acquisition moment; wherein the plurality of image acquisition devices are arranged along the width direction of the pole piece.

[0155] The number and type of image acquisition devices arranged along the width direction of the pole piece are not limited. For example, the image acquisition device is a CCD camera, and the number of image acquisition devices arranged along the width direction of the pole piece is two.

[0156] Step S122: determining an overlapping area in at least two initial images.

[0157] When at least two image acquisition devices are used to acquire images corresponding to the electrode to be inspected, the shooting fields of some image acquisition devices may overlap. Therefore, in this embodiment, the overlapping area in at least two initial images is determined.

[0158] The method for determining the overlapping area in at least two initial images is not limited and can be specifically set according to actual use needs.

[0159] Step S123: removing overlapping areas in at least two initial images, and splicing the at least two initial images after the removal to obtain an image to be detected.

[0160] In this embodiment, the overlapping area in at least two initial images is removed, and the at least two initial images after removal are spliced ​​to obtain the image to be detected. Specifically, after the overlapping area is determined, the overlapping area is removed and the images are spliced ​​to obtain the image to be detected corresponding to the electrode.

[0161] The method for splicing the at least two removed initial images is not limited and can be specifically configured according to actual use requirements.

[0162] For example, as shown in Figure 5, the image acquisition device A (the image acquisition device on the left side of Figure 5) and the image acquisition device B (the image acquisition device on the right side of Figure 5) arranged along the width direction of the pole piece are used to simultaneously acquire images of the pole piece to obtain initial image a and initial image b; the overlapping area in the initial image a and the initial image b is determined, and the overlapping area is removed from the initial image a or the initial image b; if it is removed from the initial image a, the initial image b and the initial image a after removing the overlapping area are spliced ​​to obtain the image to be detected.

[0163] Please refer to Figure 13, which is a flowchart of an embodiment of generating preset edge-grabbing area information provided by this application. It should be noted that if the results are substantially the same, the embodiments of this application are not limited to the process sequence shown in Figure 13. As shown in Figure 13, this embodiment includes:

[0164] Step S131: Acquire a sample image acquired from a pole piece.

[0165] In this embodiment, a sample image is obtained by capturing a pole piece. In one embodiment, the sample image can be obtained from local storage or cloud storage. Of course, in other embodiments, an image capture device can also be used to capture an image of a pole piece in real time to obtain a sample image, which is not limited here.

[0166] Step S132: Capture a plurality of second boundary lines in the sample image.

[0167] In this embodiment, a plurality of second boundary lines are captured in the sample image. In one embodiment, a boundary detection area of ​​the sample image is determined based on area setting information input by the user or pre-stored area setting information; and a plurality of second boundary lines are captured from the boundary detection area.

[0168] For example, as shown in Figure 14, Figure 14 is a schematic diagram of an embodiment of the boundary detection area provided by the present application. In response to the user input area setting information, the boundary detection area A of the sample image is determined, and several second boundary lines are captured from the boundary detection area A.

[0169] Step S133: using each second boundary line, obtaining information of the edge-grabbing area corresponding to each second boundary line, so as to obtain preset edge-grabbing area information.

[0170] In this embodiment, each second boundary line is used to obtain information of the edge-grabbing area corresponding to each second boundary line, so as to obtain the preset edge-grabbing area information.

[0171] In one embodiment, for each second boundary line, the position information of a first preset position point on the second boundary line is obtained and used as the position information of a second preset position point in the edge-grabbing area corresponding to the second boundary line. The first preset position point of the second boundary line is not limited and can be specifically set according to actual usage needs. For example, the first preset position point of the second boundary line is the midpoint of the second boundary line, which serves as the center point of the edge-grabbing area corresponding to the second boundary line.

[0172] In one embodiment, the size information input by the user for the second boundary line is obtained as the size information of the edge-grabbing area corresponding to the second boundary line, or the initial area corresponding to the second boundary line is displayed, the first preset position point of the second boundary line overlaps with the second preset position point of the initial area, and in response to the user's adjustment operation on the initial area, the size of the initial area is adjusted, and the size information of the adjusted initial area is obtained as the size information of the edge-grabbing area.

[0173] Please refer to Figure 15, which is a flowchart of an embodiment of step S13 shown in Figure 1. It should be noted that this embodiment is not limited to the flowchart shown in Figure 15 if the results are substantially the same. As shown in Figure 15, in the embodiment of the present application, the grayscale change in the edge-grabbing area is used to determine the first boundary line in the edge-grabbing area, specifically including:

[0174] Step S151: For each edge-grabbing area, a number of boundary points are found using the grayscale changes in the edge-grabbing area.

[0175] In this embodiment, for each edge-grabbing region, the grayscale variation within the edge-grabbing region is used to identify several boundary points. The grayscale variation between a boundary point and its adjacent pixels satisfies the boundary grayscale variation requirement. Specifically, for each edge-grabbing region, the grayscale variation between each pixel in the edge-grabbing region and its adjacent pixels is determined one by one to determine whether it satisfies the boundary grayscale variation requirement. If the grayscale variation between a pixel and its adjacent pixels satisfies the boundary grayscale variation requirement, it indicates that the pixel is located in a different partition than the adjacent pixels, and the pixel is determined to be a boundary point between two partitions in the edge-grabbing region. Otherwise, the pixel is determined to be a non-boundary point.

[0176] The grayscale change requirement is not limited and can be set according to actual usage needs. For example, the grayscale change requirement is that the grayscale difference is greater than or equal to a preset difference. The size of the preset difference is not limited and can be set according to actual usage needs. When the grayscale difference between a pixel and its adjacent pixel is greater than or equal to the preset difference, the grayscale difference between the pixel and its adjacent pixel is significant, indicating that the pixel belongs to a different partition than the adjacent pixel, and the pixel is the boundary point between the two partitions.

[0177] Step S152: performing straight line fitting using a number of boundary points in the edge grabbing area to obtain a first boundary line in the edge grabbing area.

[0178] In this embodiment, a plurality of boundary points in the edge grabbing area are used to perform straight line fitting to obtain a first boundary line in the edge grabbing area.

[0179] In one embodiment, before performing straight line fitting using several boundary points in the edge grasping area to obtain the first boundary line in the edge grasping area, abnormal boundary points are removed from the several boundary points to improve the accuracy of the obtained first boundary line in the edge grasping area.

[0180] In one embodiment, as shown in Figure 16, Figure 16 is a schematic diagram of an embodiment of the caliper tool provided in the present application. For each edge-grabbing area, after finding several boundary points using the grayscale changes in the edge-grabbing area, a cross is generated at the boundary point using the caliper tool to mark the boundary point; abnormal intersection points are eliminated, and the remaining intersection points are used to obtain the first boundary line a in the edge-grabbing area through straight line fitting.

[0181] Please refer to FIG17, which is a flow chart of an embodiment of step S14 shown in FIG1. ​​It should be noted that the embodiments of the present application are not limited to the flow sequence shown in FIG17 if substantially the same results are achieved. As shown in FIG17, this embodiment includes:

[0182] Step S171: Determine the partitions to be divided by each first boundary line.

[0183] In this embodiment, each first boundary line is determined to be used for dividing a partition.

[0184] In one embodiment, as shown in FIG. 18 , FIG. 18 is a flow chart of an embodiment of step S171 shown in FIG. 17 , determining the partitions to be divided by each first boundary line specifically includes the following sub-steps:

[0185] Step S181: Determine the partitions that each first boundary line is used to divide based on the grayscale information on both sides of each first boundary line.

[0186] In this embodiment, the partitions to be divided by each first boundary line are determined based on the grayscale information on both sides of each first boundary line. Different partitions have different grayscale values, or in other words, they belong to different grayscale intervals. Therefore, based on the grayscale information on both sides of each first boundary line, the partition types on both sides of the first boundary line can be quickly determined, thereby determining the partitions to be divided by the first boundary line.

[0187] For example, taking the grayscale interval of the partition to the left of the first boundary line A as grayscale value 0-10 and the grayscale interval of the partition to the right of the first boundary line A as grayscale value greater than 220: since the grayscale interval of the partition to the left of the first boundary line A is the grayscale interval corresponding to the photographic roller partition, the partition to the left of the first boundary line A is the photographic roller partition; since the grayscale interval of the partition to the right of the first boundary line A is the grayscale interval corresponding to the uncoated partition, the partition to the right of the first boundary line A is the uncoated partition; therefore, it is determined that the first boundary line A is used to divide the photographic roller partition and the uncoated partition.

[0188] Step S182: extracting boundary line partition information of each edge-grabbing area from the preset edge-grabbing area information.

[0189] In this embodiment, boundary line partition information for each edge-grabbing area is extracted from the preset edge-grabbing area information. The boundary line partition information includes a partition identifier, a partition name, or partition sorting information for the partition divided by the first boundary line in the edge-grabbing area. The partition sorting information indicates the order of the partition divided by the first boundary line among multiple partitions in the width direction of the electrode. The partition identifier, partition name, or partition sorting information for the partition divided by the first boundary line facilitates subsequent determination of the partition information divided by the first boundary line in each edge-grabbing area.

[0190] For example, taking the example of boundary line partition information including the partition sorting information of the partitions divided by the first boundary line in the edge gripping area: the first boundary line in the edge gripping area A is used to divide the uncoated partition and the coated partition, the uncoated partition is sorted as ① in the width direction of the electrode piece, and the coated partition is sorted as ② in the width direction of the electrode piece. For another example, taking the example of boundary line partition information including the partition identifiers of the first boundary line in the edge gripping area: the first boundary line in the edge gripping area A is used to divide the uncoated partition and the coated partition, the partition identifier of the uncoated partition is a, and the partition identifier of the coated partition is b.

[0191] Step S183: using the boundary line partition information of each edge-grabbing area, determining the partition to be divided by the first boundary line in each edge-grabbing area.

[0192] In this embodiment, the boundary line partition information of each edge-grabbing area is used to determine the partitions divided by the first boundary line in each edge-grabbing area.

[0193] For example, if the first boundary line in the edge gripping area A is used to divide the uncoated partition from the coated partition, and the uncoated partition is sorted as ① in the width direction of the electrode sheet, and the coated partition is sorted as ② in the width direction of the electrode sheet; then, the first boundary line in the edge gripping area A is used to divide the uncoated partition with the partition sorting ① from the coated partition with the partition sorting ②. For another example, if the first boundary line in the edge gripping area A is used to divide the uncoated partition from the coated partition, and the partition identifier of the uncoated partition is a, and the partition identifier of the coated partition is b; then, the first boundary line in the edge gripping area A is used to divide the uncoated partition with the partition identifier a from the coated partition with the partition identifier b.

[0194] Since there may be the same type of partitions in the electrode, according to the grayscale information on both sides of the first boundary line, the partition that the first boundary line is used to divide can be determined, but it is impossible to determine whether the partitions of the same type that other first boundary lines are used to divide are the same partition as the partition that it is used to divide; for example, it is determined that the first boundary line A is used to divide the photo roller partition and the uncoated partition, and the first boundary line B is used to divide the uncoated partition and the coated partition, but it is impossible to determine whether the uncoated partition corresponding to the first boundary line A and the uncoated partition corresponding to the first boundary line B are the same coated partition. It should be noted that when it is determined that the partitions that two first boundary lines are used to divide are the same, the two first boundary lines are the boundary lines corresponding to the same partition; for example, it is determined that the first boundary line A is used to divide the photo roller partition and the uncoated partition, and the first boundary line B is used to divide the uncoated partition and the coated partition. If the uncoated partition that the first boundary line A is used to divide and the uncoated partition that the first boundary line B is used to divide are the same uncoated partition, then the first boundary line A and the first boundary line B are determined to be the two boundary lines used to divide the uncoated partition.

[0195] Therefore, once the first boundary line in each edge-grabbing region is determined to demarcate the partition, it is possible to determine whether the partition demarcated by the first boundary line itself is the same as the partition demarcated by other first boundary lines, thereby determining the two boundary lines corresponding to the partition. For example, if first boundary line α in edge-grabbing region A is used to demarcate the uncoated partition with partition identifier a from the coated partition with partition identifier b, and first boundary line β in edge-grabbing region B is used to demarcate the uncoated partition with partition identifier b from the coated partition with partition identifier c, then first boundary line α and first boundary line β are the two boundary lines corresponding to the partition with partition identifier b.

[0196] Step S172: Acquire the distance between the two first boundary lines corresponding to each target partition as the width information of each target partition.

[0197] In this embodiment, the distance between the two first boundary lines corresponding to each target partition is obtained as the width information of each target partition. The target partition is located between the two boundary lines corresponding to the target partition, so the distance between the two first boundary lines corresponding to the target partition is the width of the target partition.

[0198] The target partition is any partition on the electrode, or a plurality of adjacent partitions. For example, the target partition is the uncoated partition on the left side of the electrode, so the distance between the two first boundary lines corresponding to the uncoated partition on the left side is used as the width of the uncoated partition on the left side. For another example, the target partition is formed by the uncoated partition on the left side and the adjacent coated partition. Therefore, the distance between the two first boundary lines corresponding to the target partition is used as the sum of the width of the uncoated partition on the left side and the width of the adjacent coated partition.

[0199] Please refer to Figure 6 and Figure 19 in combination. Figure 19 is a schematic diagram of the electrical topology structure of an embodiment of the visual inspection system provided by the present application. The present application provides a visual inspection system 90, which includes at least one image acquisition device 91, a processing device 92, and a host computer 93. At least one image acquisition device 91 is used to acquire images of the electrode piece; the processing device 92 is communicatively connected to the at least one image acquisition device 91, and is used to use the image acquired by the at least one image acquisition device 91 to inspect the electrode piece and obtain the inspection result of the electrode piece. The inspection result includes width information related to the electrode piece, and the width information is determined by using the first boundary line detected in at least one edge-grabbing area of ​​the image; the host computer 93 is connected to the processing device 92, and is used to display the image acquired by the image acquisition device 91 and / or to indicate the inspection result.

[0200] The processing device 92 can be used to detect the electrode piece using images captured by at least one image capture device 91. That is, the processing device 92 of the visual inspection system 90 can realize automatic detection of the electrode piece. The detection result includes width information related to the electrode piece. The width information is determined using the first boundary line detected in at least one edge-grabbing area of ​​the image. Based on the preset edge-grabbing area information, at least one edge-grabbing area is determined in the image to be inspected. Boundary detection is performed on each edge-grabbing area to obtain the first boundary line in each edge-grabbing area. The first boundary line in each edge-grabbing area is then used to determine the width information related to the electrode piece. Therefore, automatic detection of the electrode piece can be realized. Furthermore, the above scheme can also use the preset edge-grabbing area to determine the width information related to the electrode piece, realizing automatic detection of the width information related to the electrode piece. In addition, the preset edge-grabbing area does not need to be set by the user, thereby improving the efficiency of detecting the width information related to the electrode piece.

[0201] Furthermore, the visual inspection system 90 is also provided with a host computer 93, which can be used to display the image captured by the image acquisition device 91 so that relevant personnel can promptly know the coating status of the electrode; or, the host computer 93 can be used to prompt the detection results so that relevant personnel can promptly know the detection status of the electrode, so that when the electrode detection is abnormal, corresponding processing can be carried out in time to prevent the coating batch from being scrapped. Therefore, the visual inspection system 90 provided by the present application integrates the electrode detection function and the related information display function into one, which can realize automatic detection of the electrode and image display and / or detection result prompt.

[0202] In one embodiment, at least one host computer 93 is located at a preset position in a coating system for coating the electrode. The number and preset positions of the host computers 93 are not limited and can be set based on actual usage needs. For example, the number of host computers 93 can be 1, 2, 5, or 10, and the preset positions can be at the head or tail of the coating system.

[0203] In a specific embodiment, as shown in FIG6 , there are two host computers 93 , one of which is located at the head of the coating system and the other is located at the tail of the coating system. Since relevant personnel generally perform relevant operations at the head and / or tail of the coating system, a host computer 93 is respectively provided at the head and tail of the coating system, so that relevant personnel at the head and tail can promptly obtain information on the coating of the electrode and / or the detection of the electrode, so that relevant personnel at the head and tail can promptly take corresponding measures when they learn that the electrode detection is abnormal, thereby preventing the coating batch from being scrapped.

[0204] In other implementations, the host computer 93 also includes a mouse, a keyboard, a KVM network receiver, etc., which are not limited here.

[0205] In one embodiment, at least one image acquisition device 91 includes at least one device group, each device group includes at least one image acquisition device 91, and different device groups are used to capture images of different sides of the electrode. In other words, when it is necessary to capture images of both the front and back sides of the electrode, different device groups are used to capture images of the front and back sides of the electrode. The number of device groups and the number of image acquisition devices 91 included in each device group are not limited and can be specifically set according to actual needs. For example, the number of device groups is 2, and each device group includes one image acquisition device 91; for another example, the number of device groups is 2, and each device group includes two image acquisition devices 91; for another example, the number of device groups is 1, and the device group includes image acquisition device 1-1 and image acquisition device 1-2.

[0206] For example, as shown in Figure 6, take the case where the number of device groups is 2 and each device group includes 1 image acquisition device 91: it includes device group A and device group B, device group A includes an image acquisition device 91 (the image acquisition device located at the upper part in Figure 6), and device group B includes 1 image acquisition device 91 (the image acquisition device located at the lower part in Figure 6); after the electrode is output from the upper oven 65, it will pass through the image acquisition devices 91 in device group A and device group B. The image acquisition devices 91 included in device group A and device group B are located on both sides of the electrode, so the image acquisition device 91 of device group A captures images of one coated surface of the electrode, and the image acquisition device 91 of device group B captures images of the other coated surface of the electrode.

[0207] For another example, consider a case where there are two device groups, each of which includes two image acquisition devices: device group A and device group B, each of which includes two image acquisition devices. After the electrode is output from the upper oven, it passes through two image acquisition devices in device group A and device group B. The two image acquisition devices in device group A simultaneously capture images of one coated surface of the electrode. Simultaneously, the two image acquisition devices in device group B capture images of the other coated surface of the electrode. It should be noted that when two image acquisition devices simultaneously capture images of one coated surface of the electrode, the shooting fields of the two image acquisition devices may overlap, so the images captured by the two image acquisition devices may have overlapping areas. Therefore, if the images captured by the two image acquisition devices are to be used as the image to be inspected for the electrode, the two images captured by the two image acquisition devices need to be spliced ​​after removing the overlapping areas. In addition, using two image acquisition devices to capture images of the same coated surface increases the field of view, making it suitable for capturing images of wide-width electrode sheets.

[0208] In one embodiment, at least one device group includes a first device group and a second device group, and the processing device includes a master processing device 921 and a slave processing device 922; the master processing device 921 is connected to the first device group and is used to detect the image collected by the first device group; the slave processing device 922 is connected to the second device group and is used to detect the image collected by the second device group, obtain a second detection result, and send at least one of the image collected by the second device group and the second detection result to the master processing device 921; the master processing device 921 is connected to a host computer and is also used to send the images collected by the first device group and the second device group to the host computer, and / or to prompt the first detection result and the second detection result. That is, when the visual inspection system includes two device groups, one processing device cannot support the normal operation of both device groups at the same time, so a master-slave processing device 921 is set, and the master-slave processing device 921 is respectively connected to one device group to ensure its normal operation.

[0209] For example, as shown in FIG19 and FIG20, FIG20 is a schematic diagram of the electrical topology structure of another embodiment of the visual inspection system provided by the present application, the first device group A includes two image acquisition devices (acquisition card 1-1 and acquisition card 1-2 in FIG19), the first device group A The two image acquisition devices included (acquisition card 1-1 and acquisition card 1-2 in Figure 19) are connected to the main processing device 921, and the main processing device 921 will detect the images acquired by the two image acquisition devices included in the first device group A; the second device group B includes two image acquisition devices (acquisition card 2-1 and acquisition card 2-2 in Figure 20), and the two image acquisition devices included in the second device group B (acquisition card 2-1 and acquisition card 2-2 in Figure 20) are connected to the slave processing device 922, and the slave processing device 922 will detect the images acquired by the two image acquisition devices included in the second device group B (acquisition card 2-1 and acquisition card 2-2 in Figure 20); on the one hand, the host computer 93 receives the images acquired by the first device group A and the second device group B sent by the main processing device 921, so that relevant personnel can promptly know the coating and other related conditions of the electrode, and on the other hand, it can prompt the first detection result and the second detection result, so that relevant personnel can promptly know the detection status of the electrode.

[0210] In a specific embodiment, the image acquisition device 91 is a first type of acquisition device, and the visual detection system 90 also includes two light source modules 94, each light source module 94 includes a light source 941 and a light source controller 942 that are interconnected, and the light source controllers 942 of the two light source modules 94 are respectively connected to the main processing device 921 and the slave processing device 922, so that the corresponding connected processing device 92 instructs the light source controller 942 to control the corresponding light source 941 to operate. Specifically, the main processing device 921 corresponds to a light source module 94 (as shown in Figure 19, the main processing device 921 corresponds to light source 1 and light source controller 1), and the slave processing device 922 corresponds to a light source module 94 (as shown in Figure 20, the slave processing device 922 corresponds to light source 2 and light source controller 2); for the main processing device 921, the light source controller 942 of the corresponding light source module 94 is connected to the main processing device 921, and the light source 941 of the corresponding light source module 94 is connected to the corresponding light source controller 942; for the slave processing device 922, the light source controller 942 of the corresponding light source module 94 is connected to the slave processing device 922, and the light source 941 of the corresponding light source module 94 is connected to the corresponding light source controller 942.

[0211] In one embodiment, the master processing device and the slave processing device are connected via a network. Of course, in other embodiments, the master processing device and the slave processing device may also be connected via a physical connection line, which is not limited here.

[0212] In one embodiment, the image acquisition device 91 is a first type of acquisition device, and the visual inspection system 90 also includes a light source 941 for providing shooting light for the first type of acquisition device. The light source 941 and the first type of acquisition device are respectively located on both sides of the target normal, and the target normal is the normal of the tangent between the electrode and the roller for conveying the electrode; wherein, there is a first distance between the intersection of the optical axis of the first type of acquisition device and the acquisition surface and the target tangent point, the acquisition surface is the side of the electrode facing the first type of acquisition device, and the target tangent point is the tangent point between the electrode and the roller for conveying the electrode, and the first distance can make the incident amount of the reflected light from the roller to the light source 941 incident on the first type of acquisition device lower than the preset threshold.

[0213] Specifically, as shown in FIG. 21 , which is a schematic diagram of an embodiment of a capture point of an image acquisition device provided herein, a first distance d between the intersection point a between the optical axis of the first type of acquisition device and the acquisition surface c, and the tangent point b between the pole piece and roller 67, ensures that the amount of light reflected from the roller on light source 941 incident on the first type of acquisition device is below a preset threshold, thereby improving the quality of the image captured from the pole piece. The preset threshold is not limited.

[0214] In one embodiment, as shown in FIG22 , FIG22 is a schematic diagram of the installation of an embodiment of an image acquisition device provided by the present application. The image acquisition device 91 is a first-class acquisition device. The visual inspection system 90 further includes a light source 941 for providing shooting light for the first-class acquisition device. The light source 941 and the first-class acquisition device are respectively located on either side of a target normal e, which is the normal of the tangent line between the electrode piece and the roller 67 for conveying the electrode piece. The second distance d2 between the first-class acquisition device and the acquisition surface c is related to the focal length of the first-class acquisition device. Specifically, the second distance d2 between the first-class acquisition device and the acquisition surface c / focal length = field of view / target surface size, wherein the target surface size is equivalent to the sensor length of the image acquisition device 91.

[0215] In one embodiment, the image acquisition device 91 is a first-class acquisition device, and the visual inspection system 90 further includes a light source 941 for providing imaging light for the first-class acquisition device. The light source 941 and the first-class acquisition device are respectively located on either side of a target normal e, which is the normal of a tangent line between the electrode piece and a roller 67 for transporting the electrode piece. As shown in FIG22 , a first angle α is formed between the illumination light from the light source 941 and the target normal e, and a second angle β is formed between the optical axis of the first-class acquisition device and the target normal e. At least one of the first angle α and the second angle β is such that the illumination intensity of the imaging area of ​​the first-class acquisition device meets the required illumination intensity. The required illumination intensity is not limited and can be set according to actual needs.

[0216] In one embodiment, the image acquisition device 91 is a first type of acquisition device, and the visual inspection system 90 also includes a light source 941 for providing shooting light for the first type of acquisition device. The light source 941 and the first type of acquisition device are respectively located on both sides of the target normal e, and the target normal e is the normal of the tangent between the electrode and the roller 67 for conveying the electrode; wherein, there is a third distance between the light source 941 and the acquisition surface. When there is a third distance d3 between the light source 941 and the acquisition surface c, the light intensity of the shooting area of ​​the first type of acquisition device will be greater, so that the image captured by the subsequent image acquisition device 91 will be clearer and of higher quality.

[0217] In one embodiment, the image acquisition device 91 is a second-type acquisition device, which is connected to multiple acquisition cards corresponding to the second-type acquisition device, and the multiple acquisition cards corresponding to the second-type acquisition device are connected to the processing device 92; wherein, the multiple acquisition cards corresponding to the second-type acquisition device are connected to each other through an inter-board synchronization line, and the encoder of the visual inspection system 90 transmits an acquisition trigger signal to one of the acquisition cards, and one of the acquisition cards is synchronized with the remaining acquisition cards corresponding to the second-type acquisition device through the inter-board synchronization line to trigger the second-type acquisition device to perform image acquisition.

[0218] In one embodiment, the visual inspection system 90 further includes a signal distributor connected to the encoder. The encoder generates a capture trigger signal, which is transmitted through the signal distributor to multiple capture trigger signals for transmission to each capture card, thereby triggering the second-type capture device to perform image capture. Specifically, the encoder of the visual inspection system 90 generates a pulse signal when it rotates. Once one capture card receives the pulse signal, the remaining capture cards synchronize via the inter-board synchronization line, triggering the second-type capture device to perform image capture.

[0219] In one embodiment, the encoder of the visual inspection system 90 generates a pulse signal when it rotates. The pulse signal is divided into multiple signals after passing through a signal distributor. After each acquisition card receives the pulse signal, the multiple signals trigger the second type of acquisition device to perform image acquisition.

[0220] In one embodiment, the second type of acquisition device is a macro camera. Macro cameras utilize an integrated sensor, lens, and light source design, making them easy to install and space-saving. Cameras equipped with line sensors can capture high-resolution images over a wide range at high speed. Of course, in other embodiments, the second type of acquisition device can also be other types of acquisition devices, which are not limited here.

[0221] In one embodiment, the inter-board synchronization line is a Cameralink data line. Of course, in other embodiments, the inter-board synchronization line can also be other types of data lines, which is not limited here.

[0222] For example, as shown in Figure 23, Figure 23 is a schematic diagram of an embodiment of the electrical wiring of a macro camera provided in this application, taking the second type of acquisition device as a macro camera as an example: the four acquisition cards corresponding to the macro camera A (acquisition card 1, acquisition card 2, acquisition card 3 and acquisition card 4) are connected through the Cameralink data line B, the macro camera A is connected to the four acquisition cards corresponding to the macro camera A, and the four acquisition cards are connected to the processing device 92; the encoder C of the visual inspection system 90 transmits the acquisition trigger signal to the acquisition card 4, and the acquisition card 4 is synchronized with the acquisition card 1, acquisition card 2 and acquisition card 3 through the Cameralink data line B to trigger the macro camera A to perform image acquisition; or, the acquisition trigger signal emitted by the encoder C of the visual inspection system 90 outputs 4 acquisition trigger signals through the signal distributor, which are respectively transmitted to the acquisition card 1, acquisition card 2, acquisition card 3 and acquisition card 4, thereby triggering the macro camera A to perform image acquisition.

[0223] In one embodiment, a third distance d3 exists between the second-type acquisition device and the acquisition surface c, which is the side of the electrode facing the first-type acquisition device. In other words, using the second-type acquisition device for image acquisition can reduce the third distance d3 between the second-type acquisition device and the acquisition surface, saving space.

[0224] In one specific embodiment, the visual inspection system 90 also includes a manufacturing execution system (MES), a master device (PLC), an 8-port switch, a three-color light, a CCD master device, a camera fan, a cabinet fan, a 5-port switch, a card reader, and a KVM transmitter. The master device (PLC) is connected to network port 2 of the main processing device via the 8-port switch. The camera fan, cabinet fan, and three-color light are connected to the CCD master device, which is connected to network port 2 of the main processing device via the 8-port switch. The camera fan is used to cool the camera and may be one, two, or three. The cabinet fan is used to cool the camera cabinet and may be one, two, three, or more. The three-color light is used to flash when an electrode anomaly occurs, promptly notifying relevant personnel of the abnormal condition. The slave processing device is connected to network port 2 of the main processing device via the 8-port switch. The light source module corresponding to the main processing device is connected to network port 1 of the main processing device via its light source controller 1. The manufacturing execution system (MES) is connected to network port 1 of the main processing device. The monitoring device 193 is connected to a 5-port switch, which is connected to the VGA port of the main processing device via a KVM transmitter. A card reader is connected to the USB port of the main processing device.

[0225] In a specific embodiment, as shown in FIG20 , the light source module corresponding to the slave processing device 921 is connected to the serial port of the slave processing device 922 through its light source control. An 8-port switch is connected to the network port 1 of the slave processing device 922 .

[0226] Please continue to refer to Figure 6. The present application also provides a coating system 60, which includes a unwinding mechanism 61, a first coating mechanism (die A62 in Figure 6), a drying mechanism (lower oven 63 and upper oven 65 in Figure 6), a second coating mechanism (die B64 in Figure 6), a winding mechanism 66 and a visual inspection system 90. The visual inspection system 90 is used to obtain coating images collected from two relative coating surfaces of the electrode; use the coating images to determine coating misalignment information; wherein the coating misalignment information characterizes the misalignment of the coating area on the coating surface; based on the coating misalignment information, the coating mechanisms of the two coating surfaces and at least two of the electrode sheets are corrected so that after correction, the coating areas of the two coating surfaces are aligned and are both located at the standard coating positions in the coating surface. Among them, the unwinding mechanism 61 is used to unwind the electrode; the first coating mechanism (die A62 in Figure 6) is used to coat the first coating surface of the unwound electrode; the second coating mechanism (die B64 in Figure 6) is arranged behind the first coating mechanism and the second coating mechanism (die B62 in Figure 6), and is used to coat the second coating surface of the electrode; the drying mechanism (lower oven 63 and upper oven 65 in Figure 6) 43 is used to dry the electrode after being coated by the first coating mechanism (die A62 in Figure 6) and the second coating mechanism (die B64 in Figure 6); the winding mechanism 66 is used to wind up the dried electrode.

[0227] In one embodiment, the visual inspection system 90 further includes a first image acquisition device and a second image acquisition device, the first image acquisition device and the second image acquisition device are arranged behind the second coating mechanism, and the first image acquisition device is arranged on one side of the first coating surface, and the second image acquisition device is arranged on one side of the second coating surface.

[0228] In one embodiment, the coating system 60 or the visual inspection system 90 further includes a correction mechanism 69 (95), and the correction mechanism 69 (95) is used to correct the coating mechanism of the coating surface of the electrode.

[0229] If the technical solution of this application involves personal information, the product that applies the technical solution of this application has clearly informed the personal information processing rules and obtained the individual's voluntary consent before processing personal information. If the technical solution of this application involves sensitive personal information, the product that applies the technical solution of this application has obtained the individual's separate consent before processing sensitive personal information, and at the same time meets the "explicit consent" requirement. For example, on personal information collection devices such as cameras, a clear and prominent sign is set to inform that the personal information collection scope has been entered and personal information will be collected. If the individual voluntarily enters the collection scope, it is deemed that they agree to the collection of their personal information; or on the personal information processing device, when the personal information processing rules are notified by obvious signs / information, the individual's authorization is obtained through pop-up information or by asking the individual to upload their personal information; among which, the personal information processing rules may include information such as the personal information processor, the purpose of personal information processing, the processing method, and the type of personal information processed.

[0230] The above description is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A pole piece detection method, characterized in that: include: Acquire the image to be detected acquired from the pole piece; Determine at least one edge-grabbing area in the image to be detected according to preset edge-grabbing area information, wherein the preset edge-grabbing area information includes position information and / or size information of the edge-grabbing area; Performing boundary detection on each of the edge-grabbing areas to obtain a first boundary line in each of the edge-grabbing areas, wherein the first boundary line is used to divide different partitions of the arrangement of the pole pieces in the width direction; The width information related to the pole piece is determined by using the first boundary line in each of the edge grasping areas.

2. The method according to claim 1, characterized in that: The step of determining at least one edge-grabbing area in the image to be detected according to the preset edge-grabbing area information includes: When the electrode piece is an anode electrode piece, at least four edge-grabbing areas are determined in the image to be detected according to the preset edge-grabbing area information; or, when the electrode piece is a cathode electrode piece, at least six edge-grabbing areas are determined in the image to be detected according to the preset edge-grabbing area information.

3. The method according to claim 2, characterized in that The boundary detection of each edge-grabbing area is performed by multiple threads, and the boundary detection of each edge-grabbing area is performed by using one of the threads.

4. The method according to any one of claims 1 to 3, characterized in that: Before determining at least one edge-grabbing area in the image to be detected according to the preset edge-grabbing area information, the method further includes: Acquire a sample image acquired from a pole piece; capturing a plurality of second boundary lines in the sample image; The information of the edge-grabbing areas respectively corresponding to the second boundary lines is acquired by using the second boundary lines to obtain the preset edge-grabbing area information.

5. The method according to claim 4, characterized in that The capturing of a plurality of second boundary lines in the sample image comprises: Determining a boundary detection area of ​​the sample image according to the area setting information; Grab a plurality of the second boundary lines from the boundary detection area; And / or, using each of the second boundary lines to obtain information of the edge-grabbing areas respectively corresponding to each of the second boundary lines to obtain the preset edge-grabbing area information includes at least one of the following steps: For each second boundary line, acquiring position information of a first preset position point of the second boundary line as position information of a second preset position point in the edge grasping area corresponding to the second boundary line; The size information of the edge grabbing area corresponding to the second boundary line is obtained.

6. The method according to any one of claims 1 to 5, characterized in that: The performing boundary detection on each of the edge-grabbing areas to obtain a first boundary line in each of the edge-grabbing areas includes: For each edge grabbing area, using the grayscale change in the edge grabbing area, a number of boundary points are found, and the grayscale change between the boundary point and the adjacent pixel point meets the boundary grayscale change requirement; A plurality of boundary points in the edge grabbing area are used to perform straight line fitting to obtain a first boundary line in the edge grabbing area.

7. The method according to any one of claims 1 to 6, characterized in that: The determining of width information related to the pole piece by using the first boundary line in each of the edge grasping areas includes: Determine the partitions to be divided by each of the first boundary lines; The distance between the two first boundary lines corresponding to each target partition is obtained as the width information of each target partition, wherein the target partition is any partition on the pole piece, or a plurality of consecutive adjacent partitions are spliced ​​together.

8. The method according to claim 7, characterized in that The determining of the partitions for dividing the first boundary lines includes: Determining the partitions for dividing each first boundary line according to the grayscale information on both sides of each first boundary line; Extracting boundary line partitioning information of each of the edge grabbing areas from the preset edge grabbing area information, the boundary line partitioning information including a partition identifier, a partition name or a partition sorting information of a partition divided by the first boundary line in the edge grabbing area, the partition sorting information indicating the sorting of the partition divided by the first boundary line among a plurality of partitions in the width direction of the pole piece; and, utilizing the boundary line partitioning information of each of the edge grabbing areas, determining the partition divided by the first boundary line in each of the edge grabbing areas.

9. The method according to any one of claims 1 to 8, characterized in that: The width information includes coating-related width information capable of characterizing the position and / or width of the coating areas of the two coating surfaces of the pole piece; After determining the width information related to the pole piece by using the first boundary line in each of the edge grasping areas, the method further includes: Determine coating misalignment information using the coating-related width information, wherein the coating misalignment information represents the misalignment condition of the coating area; Based on the coating misalignment information, a correction mechanism is used to correct the coating mechanisms of the two coating surfaces and at least one of the pole pieces, so that after the correction, the coating areas of the two coating surfaces are aligned and / or are both located at the standard coating positions in the coating surfaces.

10. The method according to any one of claims 1 to 9, characterized in that: Said also includes: Determine a quality detection area in the image to be detected, wherein the quality detection area includes one or more partitions in the width direction of the pole piece; Performing quality inspection on the quality inspection area to obtain a quality inspection result of the quality inspection area.

11. The method according to claim 10, characterized in that The grayscale value of each partition of the pole piece in the acquired image belongs to a different grayscale interval; The determining of the quality detection area in the image to be detected includes: Finding the first pixel point whose grayscale value belongs to the target grayscale interval from the image to be detected; Acquire a connected domain formed by the first pixel points as the quality detection area; And / or, performing quality inspection on the quality inspection area to obtain a quality inspection result of the quality inspection area includes: The grayscale distribution in the quality detection area is used to determine whether there is a defect in the quality detection area.

12. The method according to claim 11, characterized in that The quality inspection area includes a ceramic partition and a coating partition, and the defect includes metal leakage in the ceramic partition or the coating partition; and / or, Determining whether there is a defect in the quality inspection area by using the grayscale distribution in the quality inspection area includes: Finding a number of second pixel points whose grayscale values ​​do not belong to the target grayscale interval from the quality detection area; Determine at least one suspected defect area using the plurality of second pixel points; In response to the suspected defect area meeting a preset size requirement, it is determined that the defect exists in the suspected defect area, wherein the preset size requirement includes at least one of an area meeting a preset area condition and a width meeting a preset width condition.

13. The method according to any one of claims 1 to 12, characterized in that: The step of acquiring the image to be detected obtained by collecting the electrode piece includes: Acquire at least two initial images of the pole piece acquired by at least two image acquisition devices corresponding to the same acquisition time, wherein the plurality of image acquisition devices are arranged along the width direction of the pole piece; determining an overlapping area in the at least two initial images; Removing an overlapping area of ​​the at least two initial images, and splicing the at least two initial images after the removal to obtain the image to be detected; And / or, before determining at least one edge-grabbing area in the image to be detected according to the preset edge-grabbing area information, the method further includes: In response to the image to be detected being an abnormal image, discarding the image to be detected; And / or, the image to be detected is obtained by stitching at least two initial images acquired by at least two image acquisition devices at the same acquisition time. Before acquiring the image to be detected acquired by the polar piece, the method further includes: In response to the presence of an abnormal image in the at least two initial images, the at least two initial images are discarded.

14. A visual inspection system, characterized in that: include: at least one image acquisition device for acquiring an image of the pole piece; a processing device, communicatively connected to the at least one image acquisition device, and configured to detect the pole piece using the image acquired by the at least one image acquisition device to obtain a detection result of the pole piece, wherein the detection result includes width information related to the pole piece, and the width information is determined using a first boundary line detected in at least one edge grabbing area of ​​the image; The host computer is connected to the processing device for displaying the image acquired by the image acquisition device and / or prompting the detection result.

15. The system according to claim 14, characterized in that The image acquisition device is a first-class acquisition device, and the system further comprises a light source for providing shooting light for the first-class acquisition device, the light source and the first-class acquisition device are respectively located on both sides of a target normal line, and the target normal line is a normal line of a tangent line between the pole piece and a roller for conveying the pole piece; wherein, There is a first distance between the intersection of the optical axis of the first type of collection device and the collection surface and the target tangent point, the collection surface is the side of the pole piece facing the first type of collection device, the target tangent point is the tangent point between the pole piece and the roller used to transport the pole piece, and the first distance can make the incident amount of the reflected light of the light source from the roller incident on the first type of collection device lower than a preset threshold; and / or, The second distance between the first type of acquisition device and the acquisition surface is related to the focal length of the first type of acquisition device; and / or, There is a first angle between the irradiated light of the light source and the target normal, there is a second angle between the optical axis of the first type of acquisition device and the target normal, and the size of at least one of the first angle and the second angle can make the illumination intensity of the shooting area of ​​the first type of acquisition device meet the requirements; and / or, There is a third distance between the light source and the collection surface.

16. The system according to claim 14, characterized in that The image acquisition device is a second type of acquisition device, the second type of acquisition device is connected to a plurality of acquisition cards corresponding to the second type of acquisition device, and the plurality of acquisition cards corresponding to the second type of acquisition device is connected to the processing device; Among them, multiple acquisition cards corresponding to the second type of acquisition device are connected through an inter-board synchronization line, and the encoder of the system transmits an acquisition trigger signal to one of the acquisition cards, and one of the acquisition cards is synchronized with the remaining acquisition cards corresponding to the second type of acquisition device through the inter-board synchronization line to trigger the second type of acquisition device to perform image acquisition.

17. The system according to claim 14, characterized in that The image acquisition device is a second type of acquisition device, the second type of acquisition device is connected to a plurality of acquisition cards corresponding to the second type of acquisition device, and the plurality of acquisition cards corresponding to the second type of acquisition device is connected to the processing device; The system further comprises a signal distributor connected to the encoder, and the acquisition trigger signal sent by the encoder outputs multiple acquisition trigger signals through the signal distributor to be transmitted to each acquisition card respectively to trigger the second type acquisition device to perform image acquisition.

18. The system according to claim 17, characterized in that The second type of acquisition device is a macro camera; And / or, there is a third distance between the second type of collecting device and a collecting surface, and the collecting surface is a side of the pole piece facing the first type of collecting device.

19. The system according to any one of claims 14 to 18, characterized in that The at least one image acquisition device includes at least one device group, each device group includes at least one image acquisition device, and different device groups are used to acquire images on different surfaces of the pole piece.

20. The system according to claim 19, characterized in that The at least one device group includes a first device group and a second device group, and the processing device includes a master processing device and a slave processing device; The main processing device is connected to the first device group, and is used to detect the image collected by the first device group to obtain a first detection result; the slave processing device is connected to the second device group, and is used to detect the image collected by the second device group to obtain a second detection result, and send at least one of the image collected by the second device group and the second detection result to the main processing device; The main processing device is connected to the monitoring equipment, and is also used to send the images collected by the first device group and the second device group to the monitoring equipment, and / or prompt the first detection result and the second detection result.

21. The system according to claim 20, characterized in that The image acquisition device is a first type of acquisition device, and the system further comprises two light source modules, each of which comprises a light source and a light source controller connected to each other, and the light source controllers of the two light source modules are respectively connected to the main processing device and the slave processing device, so that the correspondingly connected processing device instructs the light source controller to control the corresponding light source to work; And / or, the master processing device and the slave processing device are connected via a network.

22. The system according to any one of claims 14 to 21, characterized in that The host computer includes at least one, and the at least one host computer is arranged at a preset position of a coating system for coating the electrode piece.

23. A coating system, characterized in that: The coating system comprises: An unwinding mechanism, used for unwinding the pole piece strip; A first coating mechanism, used for coating the first coating surface of the unwound electrode sheet strip; A second coating mechanism, disposed after the first coating mechanism, for coating the second coating surface of the electrode strip; A drying mechanism, used for drying the electrode material strip after being coated by the first coating mechanism and the second coating mechanism; A winding mechanism, used for winding the pole piece strip that has been dried; A visual inspection system, the visual inspection system comprising at least one image acquisition device and a processing device, the image acquisition device being used to acquire images of a pole piece to obtain an image to be inspected; the processing device being used to determine at least one edge-grabbing area in the image to be inspected according to preset edge-grabbing area information, the preset edge-grabbing area information comprising position information and / or size information of the edge-grabbing area; performing boundary detection on each of the edge-grabbing areas to obtain a first boundary line in each of the edge-grabbing areas, the first boundary line being used to divide different partitions of the arrangement of the pole piece in the width direction; and determining width information related to the pole piece using the first boundary line in each of the edge-grabbing areas.

24. The system according to claim 23, characterized in that The visual inspection system also includes a first image acquisition device and a second image acquisition device, wherein the first image acquisition device and the second image acquisition device are arranged behind the second coating mechanism, and the first image acquisition device is arranged on one side of the first coating surface, and the second image acquisition device is arranged on one side of the second coating surface.

25. The system according to claim 23, characterized in that It also includes a deviation correction mechanism, which is used to correct the coating mechanism of the coating surface of the pole piece.

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