Test apparatus for tabs of battery cell, and battery cell production device

Abstract

A test apparatus for tabs (501) of a battery cell (500), and a battery cell (500) production device, which relate to the technical field of batteries. The test apparatus comprises an X-ray source (100), a flat panel detector (200), a bearing platform (300) and a controller (400), wherein the flat panel detector (200) is opposite an exit port of the X-ray source (100), the bearing platform (300) is located between the X-ray source (100) and the flat panel detector (200), and the controller (400) is electrically connected and / or communicatively connected to the flat panel detector (200); the controller (400) is configured to acquire a test image of tabs (501) of a battery cell (500); and the test image is a test image of the tabs (501) that is acquired by means of the flat panel detector (200) on the basis of received rays, which are emitted by the X-ray source (100), pass through the tabs (501) of the battery cell (500), which is placed on the bearing platform (300), and are projected to the flat panel detector (200). The test apparatus determines defect information of the tabs (501) on the basis of the test image. The test apparatus can implement comprehensive testing of tabs (501).

Description

Battery cell tab detection device and battery cell production equipment

[0001] Cross-references

[0002] This application refers to Chinese Patent Application No. 202310797714.9, filed on June 30, 2023, entitled “Detection Device for Battery Cell Tabs and Battery Cell Production Equipment”, which is incorporated into this application in its entirety by reference. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a battery cell tab detection device and battery cell production equipment. Background Art

[0004] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the industry's sustainable development. For electric vehicles, battery cell technology is a crucial factor in their development.

[0005] Tabs are the metal conductors that connect the positive and negative electrodes to each battery cell. During the battery cell production process, process errors can cause tab defects such as folding and breaking, affecting the reliability of the battery cell. Related technologies are unable to inspect and identify tab defects, which affects the reliability of the battery cell.

[0006] Summary of the Invention

[0007] The present application aims to solve at least one of the technical problems in the background art. To this end, one object of the present application is to provide a battery cell tab detection device and a battery cell production device to detect the battery cell tabs.

[0008] In a first aspect, embodiments of the present application provide a battery cell tab inspection device, comprising: an X-ray source; a flat-panel detector (FPD) located opposite an X-ray source exit port; a support platform located between the X-ray source and the FPD; and a controller electrically and / or communicatively connected to the FPD. The controller is configured to: obtain an inspection image of the battery cell tab, wherein the inspection image is obtained by the FPD, based on the received X-rays, emitted by the X-ray source and projected onto the battery cell tab placed on the support platform; and determine defect information of the tab based on the inspection image.

[0009] In the technical solution of the embodiment of the present application, the tabs of the battery cells can be inspected by an X-ray source, a flat-panel detector, and a carrying platform, and the detection image of the tabs can be analyzed by a controller to obtain information about the tab defects, thereby completing the inspection of the tabs. The inspection device provided in the embodiment of the present application can realize the inspection of the tabs. At the same time, the X-ray source and the flat-panel detector cooperate to have a high coverage rate for the detection of process defects of the tabs of the battery cells, and can observe defects that cannot be reliably detected by other testing methods, thereby achieving comprehensive inspection of the tabs.

[0010] In some embodiments, the controller is also electrically and / or communicatively connected to the X-ray source, and the controller is also electrically and / or communicatively connected to the carrying platform, and the pole lug includes a first pole lug and a second pole lug, and the first pole lug and the second pole lug are arranged along a first direction; wherein, obtaining a detection image of the pole lug of the battery cell includes configuring the controller to: control the carrying platform to move so that the first pole lug is located between the X-ray source and the flat-panel detector; control the X-ray source to emit rays through the first pole lug and project them onto the flat-panel detector; determine a first detection image of the first pole lug based on the rays received by the flat-panel detector; control the carrying platform to move along the first direction so that the second pole lug is located between the X-ray source and the flat-panel detector; control the X-ray source to emit rays through the second pole lug and project them onto the flat-panel detector; determine a second detection image of the second pole lug based on the rays received by the flat-panel detector; determine the detection image of the pole lug based on the first detection image and the second detection image. The two tabs (the first tab and the second tab) of the battery cell are tested separately. On the one hand, when the image is subsequently tested, less information needs to be processed for each test, and the test is faster. On the other hand, the distance between the X-ray source and the boundary of the tab will be closer in the two tests, which can reduce the impact of edge distortion on the test results to a certain extent.

[0011] In some embodiments, determining a first detection image of the first tab based on radiation received by a flat-panel detector includes configuring a controller to: capture multiple original images including the first tab based on radiation received by the flat-panel detector; and process the multiple original images to obtain the first detection image of the first tab. If only one original image is captured, and if this image contains an error, the subsequently processed first detection image will also contain errors, affecting the accuracy of the detection. In an embodiment of the present application, multiple original images are captured and processed. If one of the original images contains an error, the other original images remain correct, thereby reducing the impact of the error on the detection results.

[0012] In some embodiments, processing multiple original images to obtain a first inspection image of the first tab includes configuring a controller to: perform noise reduction processing on the multiple original images to obtain a first image; intercept an area including the first tab in the first image to obtain a second image; and perform image enhancement processing on the second image to obtain the first inspection image of the first tab. Through the processing steps described above, the first tab in the first inspection image can be made clearer, the defective area can be more prominent, and defects in the first tab can be more easily identified.

[0013] In some embodiments, the controller stores the size of the first tab, and extracts a region of the first image including the first tab to obtain a second image. This includes configuring the controller to: identify the position of the first tab in the first image based on grayscale values ​​in the first image; and extract the region of the first tab in the first image based on the position and size of the first tab to obtain the second image. Extracting the region of the first tab in the first image based on the position and size of the first tab ensures that the second image includes the first tab while preventing the second image from being too large and including too much other area, which could affect the detection of defects in the first tab.

[0014] In some embodiments, a controller stores a defect detection model, and determining tab defect information based on a test image includes configuring the controller to input the test image into the defect detection model and obtain tab defect information output by the defect detection model. The defect detection model stores multiple defect types, and after inputting the test image into the defect detection model, tab defect information in the test image can be quickly identified based on the stored defect types.

[0015] In some embodiments, the training process of the defect detection model includes: obtaining a sample inspection image including the tab of a sample battery cell, obtained by photographing under an X-ray source; marking the actual defect information in the sample inspection image; simultaneously inputting the sample inspection image into the defect detection model to obtain predicted defect information of the sample battery cell output by the defect detection model; calculating a loss value based on the actual defect information and the predicted defect information; and adjusting the parameters of the defect detection model based on the loss value. Before inspection, various defect samples of various sizes and types to be inspected can be defined according to the inspection requirements to create a sample battery cell, and the actual defect information in the sample battery cell can be marked. The sample battery cell is then inspected, and the predicted defect information of the sample battery cell output by the defect detection model is compared with the actual defect information, and the parameters of the defect detection model are continuously improved to make defect detection more accurate.

[0016] In some embodiments, the defect information includes tab folding and / or tab breakage. Tab folding and tab breakage are both tab defects. Setting tab folding and / or tab breakage as defect information can enable detection of tab defects.

[0017] In some embodiments, the X-ray source includes an integrated X-ray source. The integrated X-ray source has a low repair rate, high stability, small size, and simple subsequent maintenance. The integrated X-ray source is configured to improve the reliability of the detection device.

[0018] In some embodiments, the distance L1 between the X-ray source and the carrier platform and the distance L2 between the flat panel detector and the carrier platform satisfy: L2>L1. This allows the magnification during detection to be greater than 2, making it easier to observe tab defects from the detection image.

[0019] In some embodiments, the distance L1 between the X-ray source and the carrying platform, and the distance L2 between the flat panel detector and the carrying platform satisfy: According to the principle of similar triangles, the magnification of the detection device If the magnification factor N is too small, the magnification effect cannot be achieved well. If the magnification factor N is too large, the detection image may not be clear enough, affecting the detection effect. Limiting the magnification factor within the above range can enable the detection image to have a magnified effect while avoiding affecting the detection effect to a certain extent.

[0020] In some embodiments, the distance L1 between the X-ray source and the carrying platform satisfies the following conditions: 30mm≤L1≤50mm. If the distance L1 between the X-ray source and the carrying platform is too small, the radiation surface formed by the X-rays on the carrying surface of the carrying platform will be smaller, and some areas of the battery cell tabs may not be irradiated by the X-rays, resulting in missed detections. If the distance L1 between the X-ray source and the carrying platform is too large, the entire detection device will be larger. Limiting the distance L1 between the X-ray source and the carrying platform to 30mm≤L1≤50mm can both avoid missed detections and prevent the entire detection device from being too large to a certain extent.

[0021] In some embodiments, the distance L2 between the flat-panel detector and the carrying platform satisfies the following conditions: 50 mm ≤ L2 ≤ 200 mm. If the distance L2 between the flat-panel detector and the carrying platform is too small, the magnification factor will be too low, and the detection image will not be effectively magnified. If the distance L2 between the flat-panel detector and the carrying platform is too large, the entire detection device will be larger. Limiting the distance L2 between the flat-panel detector and the carrying platform to 50 mm ≤ L2 ≤ 200 mm can both increase the magnification factor to a certain extent and prevent the entire detection device from being too large.

[0022] In some embodiments, the voltage U of the X-ray source satisfies the following conditions: 70 kV ≤ U ≤ 90 kV, and / or the current I of the X-ray source satisfies the following conditions: 80 μA ≤ I ≤ 120 μA. This allows the X-rays emitted by the X-ray source to penetrate the tabs for detection without causing overexposure that would affect detection accuracy.

[0023] In some embodiments, the flat panel detector's frame rate F satisfies the following: 5fps≤F≤20fps. This allows the flat panel detector to capture multiple raw images at once, thereby reducing the impact of accidental errors on detection results and, to a certain extent, avoiding the need to capture too many raw images at once, which would otherwise prolong subsequent image processing time.

[0024] An embodiment of the second aspect of the present application provides a battery monomer production device, which includes the detection device of any one of the above embodiments.

[0025] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application. In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on the drawings without paying creative work.

[0027] FIG1 is a schematic structural diagram of a detection device according to some embodiments of the present application;

[0028] FIG2 is a block diagram of a detection device according to some embodiments of the present application;

[0029] FIG3 is a control flow chart of a controller according to some embodiments of the present application;

[0030] FIG4 is a control flow chart of a controller according to some embodiments of the present application;

[0031] FIG5 is a control flow chart of a controller according to some embodiments of the present application;

[0032] FIG6 is a control flow chart of a controller according to some embodiments of the present application;

[0033] FIG7 is a control flow chart of a controller according to some embodiments of the present application;

[0034] FIG8 is a control flow chart of a controller according to some embodiments of the present application;

[0035] FIG9 is a front view of a detection device according to some embodiments of the present application.

[0036] Explanation of reference numerals: 100 , X-ray source; 200 , flat panel detector; 300 , carrying platform; 400 , controller; 500 , battery cell; 501 , tab; 5011 , first tab; 5012 , second tab. DETAILED DESCRIPTION

[0037] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0039] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0040] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0042] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0043] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0044] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0045] Currently, market developments indicate that power batteries are becoming increasingly widely used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. As power battery applications continue to expand, market demand is also growing.

[0046] Battery cells may develop defects during production and use. For example, during the production process, defects such as tab folding or breaking may occur. Defective battery cells need to be removed to minimize impacts on battery reliability. However, these defects cannot be observed from the outside of the battery cell, requiring internal inspection. Related technologies cannot inspect the tabs of battery cells, impacting their reliability.

[0047] An embodiment of the present application provides a device for detecting a battery cell tab, comprising: an X-ray source, a flat-panel detector, a carrier platform, and a controller, wherein the flat-panel detector is opposite to an exit port of the X-ray source, the carrier platform is located between the X-ray source and the flat-panel detector, and the controller is electrically and / or communicatively connected to the flat-panel detector. The controller is configured to: obtain a detection image of the battery cell tab, wherein the detection image is a projection of the X-ray source's rays through the battery cell tab placed on the carrier platform onto the flat-panel detector, and the flat-panel detector obtains a detection image of the tab based on the received rays; and determine tab defect information based on the detection image. The battery cell tab is detected by the X-ray source and the flat-panel detector to obtain a detection image, and then the defects of the battery cell tab are identified through the detection image, thereby achieving detection of the battery cell tab.

[0048] The battery cell tab detection device disclosed in the embodiments of this application can test battery cells that have just left the factory, determine whether the battery cells are qualified based on the test results, and thus eliminate unqualified battery cells, which can improve the reliability of the battery cells to a certain extent. It can also be used to test battery cells that have been used for a period of time to test the reliability of the battery cells.

[0049] Embodiments of the present application provide a battery cell tab inspection device. Figure 1 is a schematic diagram of the structure of the inspection device according to some embodiments of the present application. Referring to Figure 1 , the inspection device includes an X-ray source 100, a flat-panel detector 200, and a supporting platform 300. The flat-panel detector 200 is positioned opposite the X-ray source 100's emission port, and the supporting platform 300 is positioned between the X-ray source 100 and the flat-panel detector 200. A battery cell 500 is also shown in the figure.

[0050] FIG2 is a block diagram of a detection device according to some embodiments of the present application. Referring to FIG2 , the detection device further includes a controller 400 , which is electrically and / or communicatively connected to the flat panel detector 200 .

[0051] FIG3 is a control flow chart of a controller according to some embodiments of the present application. Referring to FIG3 , the controller 400 is configured as follows:

[0052] Step S10: Acquire a detection image of the tab of the battery cell.

[0053] The detection image is the radiation emitted by the X-ray source 100 and projected onto the flat panel detector 200 through the tab 501 of the battery cell 500 placed on the carrying platform 300. The flat panel detector 200 obtains the detection image of the tab 501 based on the received radiation.

[0054] Step S20: Determine defect information of the tab based on the detection image.

[0055] In the embodiments of the present application, the battery cell 500 can be either a laminated or wound battery cell. The battery cell is shaped like a rectangular parallelepiped, with two opposing large faces and four side faces connecting the two large faces. In one implementation of the present application, one of the large faces of the battery cell 500 is placed on the supporting surface of the supporting platform 300, meaning that the thickness direction Z of the battery cell 500 is perpendicular to the supporting surface of the supporting platform 300.

[0056] For example, when using a detection device to detect a battery cell 500, the battery cell 500 can be placed on a carrying platform 300 so that the large surface of the battery cell 500 is in contact with the carrying surface of the carrying platform 300, that is, the thickness direction Z of the battery cell 500 is perpendicular to the carrying surface, and then an X-ray source 100 is used to project X-rays onto the tab 501 of the battery cell 500 and project them onto the flat-panel detector 200. The flat-panel detector 200 obtains a detection image of the tab 501 based on the received rays.

[0057] The X-ray source 100 emits rays with good transmissivity, thus enabling testing of thicker battery cells. Furthermore, X-ray testing technology has a high coverage rate for process defects in battery cell tabs, enabling detection of defects that cannot be reliably detected by other testing methods.

[0058] The flat panel detector 200 can convert the X-rays emitted by the X-ray source 100 into electrical signals. The flat panel detector 200 can increase the image readout speed, reduce the exposure time, and thus improve efficiency.

[0059] X-rays emitted by X-ray source 100 are penetrating. Materials of varying thicknesses attenuate the X-rays to varying degrees, resulting in varying amounts of X-rays detected by flat-panel detector 200. Flat-panel detector 200 contains a layer of radioluminescent material that, when stimulated by X-rays, emits visible light signals. These visible light signals are then transmitted to a photoelectric converter, converted into electrical signals. These signals are then output as digital signals through internal electrical signal transmission circuits, representing the contrast between light and dark in the image. X-rays attenuate after passing through the object being inspected. The more X-rays that pass through, the more luminescent signals from the photosensitive material, resulting in a brighter area in the final image. Conversely, the fewer X-rays that pass through, the darker the area in the image.

[0060] In an embodiment of the present application, the flat panel detector 200 and the X-ray source 100 can be controlled to move, or the carrying platform 300 can be controlled to move, or the flat panel detector 200 and the X-ray source 100 and the carrying platform 300 can be controlled to move at the same time, so that the tab 501 of the battery cell 500 is located between the flat panel detector 200 and the X-ray source 100. During detection, the rays emitted by the X-ray source 100 can pass through the tab 501 and be projected onto the flat panel detector 200.

[0061] In an embodiment of the present application, the X-ray source 100 can be installed on a mobile platform, which can move in three mutually perpendicular directions. The movement of the X-ray source 100 can be achieved by controlling the movement of the mobile platform.

[0062] Similarly, the flat panel detector 200 and the carrying platform 300 may also be installed in the same manner as the X-ray source 100 to achieve movement of the flat panel detector 200 and the carrying platform 300 .

[0063] In other implementations of the present application, the carrying platform 300 may be a conveyor belt, or the carrying platform 300 may be a ring guide rail, etc., to achieve the mobility of the carrying platform 300.

[0064] In the embodiment of the present application, the controller 400 is electrically and / or communicatively connected to the flat panel detector 200 , so that the controller 400 can receive a detection image of the tab 501 .

[0065] In the embodiment of the present application, the load-bearing capacity of the carrying platform 300 is greater than the weight of the placed battery cells 500 .

[0066] In some embodiments of the present application, the controller 400 is electrically connected to the flat panel detector 200. In other embodiments of the present application, the controller 400 is communicatively connected to the flat panel detector 200; or the controller 400 is both communicatively and electrically connected to the flat panel detector 200.

[0067] In the embodiment of the present application, the defect information of the tab 501 includes morphological defects such as folding and breaking of the tab 501 .

[0068] In the embodiment of the present application, the defect information of the tab 501 can be used to indicate whether the battery cell 500 is qualified.

[0069] In the embodiment of the present application, if the tab 501 is folded or broken, a grayscale change will appear in the detection image, and the defect information of the tab 501 can be determined based on the grayscale change in the detection image.

[0070] The controller 400 may include a memory and a processor, wherein the memory is used to store instructions, and the processor is used to read the instructions and execute commands according to the instructions.

[0071] In an embodiment of the present application, the flat panel detector 200 can be calibrated before detection begins to reduce errors in the detected image. For example, the flat panel detector 200 needs to be calibrated before formal operation. Before calibration, it is necessary to ensure that there is no debris on the X-ray source 100 outlet and the surface of the flat panel detector 200, and there are no obstructions between the X-ray source 100 and the flat panel detector 200. The X-rays must fully cover the receiving surface of the flat panel detector 200. The grayscale value of the image of the detection device at this time can be adjusted to the calibrated grayscale value.

[0072] The detection device provided in the embodiment of the present application can detect the tabs of the battery cell through the X-ray source 100, the flat panel detector 200 and the carrying platform 300, and analyze the detection image of the tab 501 through the controller 400 to obtain defect information of the tab 501, thereby completing the detection of the tab 501. The detection device provided in the embodiment of the present application can realize the detection of the tab 501. At the same time, the X-ray source 100 and the flat panel detector 200 cooperate to have a high detection coverage rate for process defects of the tab 501 of the battery cell, and can observe defects that cannot be reliably detected by other testing methods, thereby realizing comprehensive detection of the tab 501.

[0073] According to some embodiments of the present application, referring to FIG2 , the controller 400 is further electrically and / or communicatively connected to the X-ray source 100, and the controller 400 is further electrically and / or communicatively connected to the carrier platform 300. Referring to FIG1 , the tabs 501 include a first tab 5011 and a second tab 5012, and the first tab 5011 and the second tab 5012 are arranged along a first direction Y.

[0074] FIG4 is a control flow chart of a controller according to some embodiments of the present application. Referring to FIG4 , step S10 includes configuring the controller 400 to:

[0075] Step S11: controlling the carrying platform to move so that the first tab is located between the X-ray source and the flat panel detector.

[0076] Step S12: Control the X-ray source to emit rays that pass through the first tab and project onto the flat panel detector.

[0077] Step S13: determining a first detection image of the first tab based on the rays received by the flat panel detector.

[0078] Step S14: controlling the carrying platform to move along the first direction so that the second electrode tab is located between the X-ray source and the flat panel detector.

[0079] Step S15: Control the X-ray source to emit rays that pass through the second electrode tab and project onto the flat panel detector.

[0080] Step S16: determining a second detection image of the second tab based on the rays received by the flat panel detector.

[0081] Step S17: determining a detection image of the tab based on the first detection image and the second detection image.

[0082] In the embodiment of the present application, the movement of the battery cell 500 is controlled by controlling the movement of the carrying platform 300. The battery cell 500 is relatively small, and controlling the movement of the battery cell 500 is more convenient than controlling the movement of the X-ray source 100 and the flat panel detector 200.

[0083] In an embodiment of the present application, the carrying platform 300 is movable, and the moving trajectory of the carrying platform 300 passes between the X-ray source 100 and the flat panel detector 200. After the detection of the current battery cell is completed, the carrying platform 300 can be moved so that the detection device can detect another battery cell, that is, continuous detection of battery cells can be achieved, thereby improving detection efficiency.

[0084] In the embodiment of the present application, the position of the battery cell 500 can be adjusted by moving the position of the carrying platform 300 so that the tab 501 of the battery cell 500 can be located between the X-ray source 100 and the flat panel detector 200 .

[0085] In an embodiment of the present application, when inspecting the first pole lug 5011, the position can be adjusted so that the line connecting the center of the X-ray source 100 and the center of the surface of the first pole lug 5011 facing the X-ray source 100 is perpendicular to the surface of the first pole lug 5011 facing the X-ray source 100, and then the inspection of the first pole lug 5011 is completed. When inspecting the second pole lug 5012, the carrying platform can be controlled to move along the first direction Y, and the movement distance is equal to the distance between the center of the surface of the first pole lug 5011 facing the X-ray source 100 and the center of the surface of the second pole lug 5012 facing the X-ray source 100. In this way, when inspecting the second pole lug 5012, the line connecting the center of the X-ray source 100 and the center of the surface of the second pole lug 5012 facing the X-ray source 100 is perpendicular to the surface of the second pole lug 5012 facing the X-ray source 100, thereby reducing the impact of edge distortion.

[0086] In an embodiment of the present application, the two tabs (the first tab 5011 and the second tab 5012) of the battery cell 500 are detected separately. On the one hand, when the image is subsequently detected, less information needs to be processed for each detection, and it is faster; on the other hand, the distance between the X-ray source 100 and the boundary of the tab will be smaller in the two detections, which can reduce the impact of edge distortion on the detection results to a certain extent.

[0087] According to some embodiments of the present application, FIG5 is a control flow chart of a controller in some embodiments of the present application. Referring to FIG5 , step S13 includes configuring the controller 400 to:

[0088] Step S131: collecting a plurality of original images including the first tab based on the rays received by the flat panel detector.

[0089] Step S132: Process the multiple original images to obtain a first detection image of the first tab.

[0090] In an embodiment of the present application, the original image is an unprocessed image, and the first pole ear 5011 in the image is not clear enough. After processing multiple original images, the first pole ear 5011 in the image becomes clearer, and defects of the first pole ear 5011 are easier to identify.

[0091] In the embodiments of the present application, if only one original image is captured, any errors in this image will cause errors in the subsequently processed first detection image, affecting detection accuracy. In the embodiments of the present application, multiple original images are captured and processed. If an error occurs in one original image, the other original images remain correct, thus minimizing the impact of errors on detection results.

[0092] In the embodiment of the present application, if the battery cell 500 , the X-ray source 100 , and the flat panel detector 200 are all fixed during the acquisition process, the difference between the multiple original images is small.

[0093] In the embodiment of the present application, the number of collected original images of the first tab can be set according to needs. For example, 10 original images can be collected.

[0094] According to some embodiments of the present application, FIG6 is a control flow chart of a controller in some embodiments of the present application. Referring to FIG6 , step S132 includes configuring the controller 400 to:

[0095] Step S1321: performing noise reduction processing on the multiple original images to obtain a first image.

[0096] Step S1322: intercepting the area including the first tab in the first image to obtain a second image.

[0097] Step S1323: performing image enhancement processing on the second image to obtain a first detection image of the first tab.

[0098] In the embodiment of the present application, the noise reduction process can remove irrelevant information in multiple original images, reduce the noise in the original images, and improve the signal-to-noise ratio of the original images.

[0099] In an embodiment of the present application, after obtaining the first image, the first image can be saved, and multiple original images can be deleted to release memory.

[0100] The original image includes not only the first pole tab 5011 but also other areas. In the embodiment of the present application, the area with the first pole tab 5011 is cut out. On the one hand, it can reduce subsequent calculations, and on the other hand, it can reduce the impact of errors in other areas on the defect detection of the first pole tab 5011.

[0101] In an embodiment of the present application, multiple original images are processed through the above steps to obtain a first detection image of the first pole tab 5011. A similar method can also be used to control the flat panel detector 200 to collect multiple original images including the second pole tab 5012, and perform the above processing on the multiple original images to obtain a second detection image of the second pole tab 5012.

[0102] In an embodiment of the present application, image enhancement processing performed on the second image includes contrast enhancement and / or filtering, which can increase the contrast of various parts of the second image, highlight the tab defect area, and facilitate algorithm recognition. The image enhancement processing performed on the second image includes contrast enhancement and / or filtering, and can be characterized as performing contrast enhancement only on the second image, filtering only on the second image, or both contrast enhancement and filtering on the second image.

[0103] In the embodiment of the present application, through the processing of the above steps, the first pole tab 5011 in the first detection image can be made clearer, the defective area can be more prominent, and the defect in the first pole tab 5011 can be more easily identified.

[0104] In an embodiment of the present application, the inspection image and the corresponding defect information can be uploaded to a cloud system for easy viewing and data tracing.

[0105] According to some embodiments of the present application, the controller 400 stores the size of the first tab 5011. FIG7 is a control flow chart of the controller in some embodiments of the present application. Referring to FIG7, step S1322 includes configuring the controller 400 to:

[0106] Step S13221: Identify the position of the first tab in the first image based on the grayscale value in the first image.

[0107] Step S13222: Based on the position and size of the first tab, cut out the area including the first tab in the first image to obtain a second image.

[0108] Since materials of different thicknesses have different attenuation degrees for X-rays, different grayscale values ​​are displayed in the first image. The outline of the first tab 5011 can be identified through the grayscale value, thereby determining the position of the first tab 5011 in the first image.

[0109] The controller 400 stores the size of the first tab 5011 and leaves a certain size tolerance for interception so that the intercepted area is slightly larger than the first tab. This can avoid, to a certain extent, intercepting part of the first tab and affecting the accuracy of detection.

[0110] For example, the difference between the area of ​​the intercepted region and the area of ​​the first tab in the first image, and the ratio of the area of ​​the first tab in the first image to the area of ​​the first tab in the first image are greater than or equal to 5% and less than or equal to 20%. This can leave a certain dimensional tolerance for the interception while, to a certain extent, avoiding the intercepted region being too large, which would affect subsequent calculations.

[0111] In an embodiment of the present application, based on the position of the first pole lug and the size of the first pole lug, the area including the first pole lug in the first image is cut out, so that the second image can include the first pole lug 501, while at the same time avoiding to a certain extent that the second image is too large and includes too many other areas, which affects the defect detection of the first pole lug 5011.

[0112] According to some embodiments of the present application, the controller 400 stores a defect detection model, and step S20 includes configuring the controller 400 to:

[0113] Step S21: inputting the detection image into the defect detection model to obtain the tab defect information output by the defect detection model.

[0114] In an embodiment of the present application, a plurality of defect types are stored in the defect detection model. After the detection image is input into the defect detection model, the defect information of the tab in the detection image can be quickly identified based on the stored defect types.

[0115] In an embodiment of the present application, the various defect types stored in the defect detection model include various information such as the type of defect, the size of the defect, and the location of the defect.

[0116] According to some embodiments of the present application, FIG8 is a control flow chart of a controller in some embodiments of the present application. Referring to FIG8 , the training process of the defect detection model includes:

[0117] Step S30: obtaining a sample inspection image including a tab of a sample battery cell obtained by photographing under irradiation of an X-ray source.

[0118] Step S40: marking the real defect information in the sample detection image.

[0119] Step S50: inputting the sample detection images into the defect detection model simultaneously to obtain predicted defect information of the sample battery cell output by the defect detection model.

[0120] Step S60: Calculate the loss value based on the actual defect information and the predicted defect information.

[0121] Step S70: Adjusting parameters of the defect detection model based on the loss value.

[0122] In the embodiment of the present application, not only can the parameters of the defect detection model be improved through sample battery cells, but the detection image of the tab detected each time can also be used to improve the parameters of the defect detection model.

[0123] For example, after the detection is completed, the defects in the detection image can be calibrated to facilitate observation and verification by the staff. If errors occur, the parameters of the defect detection model can be adjusted according to the errors to form a more accurate defect detection model.

[0124] For example, the defect detection model can continuously learn the grayscale features of the detection image through a convolutional neural network, adjust internal parameters, and improve the defect detection model.

[0125] In the embodiments of the present application, prior to testing, a sample battery cell can be created by defining the various sizes and types of defects to be detected according to the testing requirements, and the actual defect information in the sample battery cell can be marked. The sample battery cell is then tested, and the predicted defect information output by the defect detection model is compared with the actual defect information. The parameters of the defect detection model are continuously improved to achieve more accurate defect detection.

[0126] According to some embodiments of the present application, the defect information includes tab folding and / or tab breakage.

[0127] Tab folding and tab breakage are both tab defects. By setting tab folding and / or tab breakage as defect information, the tab defects can be detected.

[0128] According to some embodiments of the present application, the X-ray source 100 includes an integrated X-ray source.

[0129] The integrated X-ray source has a low repair rate, high stability, small size, and simple subsequent maintenance. The X-ray source 100 is set as an integrated X-ray source to improve the reliability of the detection device.

[0130] According to some embodiments of the present application, FIG9 is a front view of a detection device according to some embodiments of the present application. Referring to FIG9 , the distance between the X-ray source 100 and the carrying platform 300 is L1, and the distance between the flat panel detector 200 and the carrying platform 300 is L2, where L2 and L1 satisfy: L2>L1.

[0131] In the embodiments of the present application, during the detection process, it can be understood that the distance L1 between the X-ray source 100 and the carrying platform 300 is the distance between the X-ray source 100 and the battery cell 500, where the thickness of the battery cell 500 is smaller than L1 and can be ignored. The distance L2 between the flat panel detector 200 and the carrying platform 300 is the distance between the flat panel detector 200 and the battery cell 500, where the distance L2 between the flat panel detector 200 and the carrying platform 300 is the distance between the flat panel detector 200 and the battery cell 500.

[0132] In the embodiment of the present application, the X-ray source 100 emits a conical shape. According to the principle of similar triangles, the magnification during detection is

[0133] In the embodiment of the present application, L2>L1 is defined so that the magnification during detection is greater than 2, making it easier to observe the tab defect from the detection image.

[0134] According to some embodiments of the present application, the distance L1 between the X-ray source 100 and the carrying platform 300 and the distance L2 between the flat panel detector 200 and the carrying platform 300 satisfy:

[0135] In the embodiment of the present application, if the magnification factor N is too small, the magnification effect cannot be achieved well. If the magnification factor N is too large, it may cause the detection image to be not clear enough, affecting the detection effect. The magnification factor is limited to the above range, so that the detection image can achieve the magnification effect while also avoiding affecting the detection effect to a certain extent.

[0136] According to some embodiments of the present application, the distance L1 between the X-ray source 100 and the carrying platform 300 satisfies: 30 mm (millimeter) ≤ L1 ≤ 50 mm.

[0137] In the embodiment of the present application, the outer contour of the X-ray emitted by the X-ray source 100 is conical. The smaller the distance L1 between the X-ray source 100 and the carrying platform 300 is, the smaller the radiation surface formed by the X-ray on the carrying surface of the carrying platform 300 is.

[0138] In the embodiments of the present application, if the distance L1 between the X-ray source 100 and the carrying platform 300 is too small, the radiation area formed by the X-rays on the carrying surface of the carrying platform 300 will be smaller, and part of the tab 501 of the battery cell 500 may not be irradiated by the X-rays, resulting in missed detection. If the distance L1 between the X-ray source 100 and the carrying platform 300 is too large, the entire detection device will be larger. Limiting the distance L1 between the X-ray source 100 and the carrying platform 300 to 30 mm ≤ L1 ≤ 50 mm can both avoid missed detections to a certain extent and prevent the entire detection device from being too large.

[0139] In the embodiment of the present application, the distance L1 between the X-ray source 100 and the carrying platform 300 can be adjusted so that the detection device can detect battery cells 500 of different sizes.

[0140] According to some embodiments of the present application, the distance L2 between the flat panel detector 200 and the carrying platform 300 satisfies: 50 mm ≤ L2 ≤ 200 mm.

[0141] In the embodiments of the present application, if the distance L2 between the flat panel detector 200 and the carrying platform 300 is too small, the magnification factor will be too low, and the detection image will not be effectively magnified. If the distance L2 between the flat panel detector 200 and the carrying platform 300 is too large, the entire detection device will be larger. Limiting the distance L2 between the flat panel detector 200 and the carrying platform 300 to 50 mm ≤ L2 ≤ 200 mm can both increase the magnification factor to a certain extent and prevent the entire detection device from being too large.

[0142] According to some embodiments of the present application, the voltage U of the X-ray source 100 satisfies: 70KV (kilovolts) ≤ U ≤ 90KV, and / or the current I of the X-ray source 100 satisfies: 80μA (microamperes) ≤ I ≤ 120μA.

[0143] The energy of the X-rays emitted by the X-ray source 100 is related to the voltage U of the X-ray source 100. The greater the voltage U of the X-ray source 100, the greater the energy of the X-rays emitted by the X-ray source 100. The intensity of the X-rays emitted by the X-ray source 100 is related to the current I of the X-ray source 100. The greater the current I of the X-ray source 100, the greater the intensity of the X-rays emitted by the X-ray source 100.

[0144] The detection device provided in the embodiment of the present application is used to detect the tab 501 of the battery cell 500. The thickness of the tab 501 is thinner than the thickness of the battery cell 500 body. When detecting the tab 501, the voltage U of the X-ray source 100 and the current I of the X-ray source 100 must meet the requirements that the X-rays can penetrate the tab 501.

[0145] In an embodiment of the present application, the voltage U of the X-ray source 100 may satisfy: 70KV≤U≤90KV; or the current I of the X-ray source 100 may satisfy: 80μA≤I≤120μA; or the voltage U of the X-ray source 100 may satisfy: 70KV≤U≤90KV, and the current I of the X-ray source 100 may satisfy: 80μA≤I≤120μA.

[0146] In an embodiment of the present application, the voltage U of the X-ray source 100 is set to 70KV≤U≤90KV, and / or the current I of the X-ray source 100 is set to 80μA≤I≤120μA, so that the X-rays emitted by the X-ray source 100 can penetrate the pole ear 501 to achieve detection, and at the same time will not be overexposed, affecting the accuracy of the detection.

[0147] According to some embodiments of the present application, the frame rate F of the flat panel detector 200 satisfies: 5fps≤F≤20fps. fps stands for Frames Per Second, i.e., the number of frames transmitted per second. In the embodiments of the present application, fps can be expressed as the number of original images collected per second.

[0148] The frame rate F of the flat panel detector 200 is related to the number of original images collected at one time by the flat panel detector 200. By collecting multiple original images, the influence of accidental errors on the detection results is reduced.

[0149] In an embodiment of the present application, the frame rate F of the flat-panel detector 200 is set to 5fps≤F≤20fps, so that the flat-panel detector 200 can capture multiple original images at a time, which reduces the impact of accidental errors on the detection results. At the same time, it avoids, to a certain extent, capturing too many original images at a time, which makes the subsequent image processing time longer.

[0150] An embodiment of the present application provides a battery cell production device, comprising the detection device of any one of the above embodiments.

[0151] The detection device provided in the embodiment of the present application can detect battery cells after production, and remove battery cells that fail the tab defect detection, thereby improving the safety of the battery cells.

[0152] The detection device provided in the embodiment of the present application can be placed behind the battery cell winding or lamination equipment. After winding or lamination, the pole pieces become battery cells. The battery cells are placed on the carrying platform by a robot on the logistics line without disassembly or additional processing, thereby realizing the detection of the battery cell pole ears.

[0153] In an embodiment of the present application, the battery cell production equipment may include multiple detection devices, which are arranged along the first direction Y. The multiple detection devices can simultaneously detect multiple battery cells 500 respectively, which can improve the detection efficiency to a certain extent.

[0154] An embodiment of the present application provides a device for detecting a battery cell tab, the detection device comprising an X-ray source 100, a flat panel detector 200, a carrying platform 300, and a controller 400. The flat panel detector 200 is opposite to the exit port of the X-ray source 100, and the X-ray source 100, the flat panel detector 200, and the carrying platform 300 are all movable, and the moving trajectory of the carrying platform 300 passes between the X-ray source 100 and the flat panel detector 200. The controller 400 is electrically and / or communicatively connected to the X-ray source 100, the controller 400 is electrically and / or communicatively connected to the flat panel detector 200, and the controller 400 is electrically and / or communicatively connected to the carrying platform 300. The tab 501 of the battery cell 500 comprises a first tab 5011 and a second tab 5012. The controller 400 is configured as follows:

[0155] Step S81: controlling the carrying platform to move so that the first electrode tab is located between the X-ray source and the flat panel detector.

[0156] Step S82: Control the X-ray source to emit rays that pass through the first tab and project onto the flat panel detector.

[0157] Step S83: determining a first detection image of the first tab based on the rays received by the flat panel detector.

[0158] Step S84: controlling the carrying platform to move along the first direction so that the second electrode tab is located between the X-ray source and the flat panel detector.

[0159] Step S85: Control the X-ray source to emit rays that pass through the second electrode tab and project onto the flat panel detector.

[0160] Step S86: Determine a second detection image of the second tab based on the rays received by the flat panel detector.

[0161] Step S87: Determine a detection image of the tab based on the first detection image and the second detection image.

[0162] Step S88: inputting the detection image into the defect detection model to obtain the tab defect information output by the defect detection model.

[0163] Step S89: Determine the quality inspection result of the tab of the battery cell based on the defect information.

[0164] The inspection device provided in the embodiment of the present application can realize fully automatic inspection of the tabs of battery cells with high inspection speed and accuracy.

[0165] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell tab detection device, comprising: X-ray source; A flat panel detector, opposite to the exit port of the X-ray source; A carrying platform, located between the X-ray source and the flat panel detector; A controller, electrically and / or communicatively connected to the flat panel detector; Wherein, the controller is configured as: Acquire a detection image of the tab of the battery cell, wherein the detection image is a detection image of the tab acquired by the flat-panel detector based on the received radiation, when the radiation emitted by the X-ray source is projected onto the flat-panel detector through the tab of the battery cell placed on the carrying platform; Defect information of the tab is determined based on the detection image.

2. The detection device according to claim 1, wherein: The controller is also electrically and / or communicatively connected to the X-ray source, and the controller is also electrically and / or communicatively connected to the carrying platform, the pole lug comprises a first pole lug and a second pole lug, and the first pole lug and the second pole lug are arranged along a first direction; Wherein, obtaining the detection image of the tab of the battery cell includes configuring the controller to: Controlling the carrying platform to move so that the first pole ear is located between the X-ray source and the flat panel detector; Controlling the X-ray source to emit rays that pass through the first pole ear and project onto the flat panel detector; Determine a first detection image of the first pole lug based on the rays received by the flat panel detector; Controlling the carrying platform to move along the first direction so that the second pole ear is located between the X-ray source and the flat panel detector; Controlling the X-ray source to emit rays that pass through the second pole ear and project onto the flat panel detector; Determine a second detection image of the second pole lug based on the rays received by the flat panel detector; A detection image of the tab is determined based on the first detection image and the second detection image.

3. The detection device according to claim 2, wherein: Determining a first detection image of the first pole lug based on the radiation received by the flat panel detector includes configuring the controller to: Collecting a plurality of original images including the first pole lug based on the rays received by the flat panel detector; The plurality of original images are processed to obtain a first detection image of the first electrode tab.

4. The detection device according to claim 3, wherein: Processing the plurality of original images to obtain a first detection image of the first electrode lug includes configuring the controller to: Performing noise reduction processing on the multiple original images to obtain a first image; intercepting a region including the first electrode tab in the first image to obtain a second image; The second image is subjected to image enhancement processing to obtain a first detection image of the first electrode tab.

5. The detection device according to claim 4, wherein: The controller stores the size of the first pole lug, and intercepts a region including the first pole lug in the first image to obtain a second image, including configuring the controller to: Identifying a position of the first pole lug in the first image based on a grayscale value in the first image; Based on the position of the first pole tab and the size of the first pole tab, a region including the first pole tab in the first image is cut out to obtain a second image.

6. The detection device according to any one of claims 1 to 5, wherein: The controller stores a defect detection model, and determines the defect information of the tab based on the detection image, including configuring the controller to: The detection image is input into a defect detection model to obtain defect information of the tab output by the defect detection model.

7. The detection device according to claim 6, wherein: The training process of the defect detection model includes: Acquire a sample detection image including a tab of a sample battery cell obtained by photographing under the irradiation of the X-ray source; Marking real defect information in the sample inspection image; Inputting the sample detection images into the defect detection model simultaneously to obtain predicted defect information of the sample battery cell output by the defect detection model; Calculating a loss value based on the actual defect information and the predicted defect information; and Parameters of the defect detection model are adjusted based on the loss value.

8. The detection device according to any one of claims 1 to 7, wherein: The defect information includes tab folding and / or tab breakage.

9. The detection device according to any one of claims 1 to 8, wherein: The X-ray source comprises an integrated X-ray source.

10. The detection device according to any one of claims 1 to 9, wherein: The distance L1 between the X-ray source and the carrying platform, and the distance L2 between the flat panel detector and the carrying platform satisfy: L2>L1.

11. The detection device according to any one of claims 1 to 10, wherein: The distance L1 between the X-ray source and the carrying platform, and the distance L2 between the flat panel detector and the carrying platform satisfy:

12. The detection device according to any one of claims 1 to 11, wherein: The distance L1 between the X-ray source and the carrying platform satisfies: 30 mm ≤ L1 ≤ 50 mm.

13. The detection device according to any one of claims 1 to 12, wherein: The distance L2 between the flat panel detector and the carrying platform satisfies: 50mm≤L2≤200mm.

14. The detection device according to any one of claims 1 to 13, wherein: The voltage U of the X-ray source satisfies: 70KV≤U≤90KV, and / or the current I of the X-ray source satisfies: 80μA≤I≤120μA.

15. The detection device according to any one of claims 1 to 14, wherein: The frame rate F of the flat panel detector satisfies: 5fps≤F≤20fps.

16. A battery monomer production device, comprising the detection device according to any one of claims 1 to 15.

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