Battery inspection apparatus and method, and battery production device

Abstract

The present application provides a battery inspection apparatus and a battery production device, and belongs to the technical field of batteries. The battery inspection apparatus comprises a bearing assembly, a pulse-type ray source, a detector, and a first driving assembly. The bearing assembly is used for bearing a battery under test and driving said battery to move in a first direction. The pulse-type ray source is configured to pulsingly emit a detection ray to an area to undergo detection of said battery on the bearing assembly. The detector and the pulse-type ray source are oppositely arranged and are each located on one side of the bearing assembly, and the detector receives a detection ray that is emitted by the pulse-type ray source and penetrates through the area to undergo detection of said battery. The first driving assembly is connected to the pulse-type ray source and the detector, and the first driving assembly is used for driving the pulse-type ray source and the detector to rotate in the circumferential direction of a first axis of rotation to collect a detection image of the area to undergo detection.

Description

Battery testing device, method and battery production equipment

[0001] Cross-references

[0002] This application refers to Chinese patent application No. 202321707871.8, filed on June 30, 2023, entitled “Battery Detection Device and Battery Production Equipment,” which is incorporated herein by reference in its entirety. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a battery detection device, method and battery 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 sustainable development of the automotive industry. For electric vehicles, battery technology is a key factor in their development.

[0005] During the battery production process, various internal defects can occur, such as wrinkled electrodes, folded heads, cracked electrodes, dark marks on electrodes, unqualified electrode misalignment, and excessive electrode gaps. These defects can affect battery quality and safety. Therefore, detecting internal defects in batteries is crucial. Currently, internal defect detection is typically performed through manual observation of the battery's appearance, which can be inaccurate.

[0006] Summary of the Invention

[0007] The present application aims to solve at least one of the technical problems existing in the background art. To this end, one purpose of the present application is to provide a battery detection device, method and battery production equipment to improve the problem of low accuracy in battery internal defect detection in the related art.

[0008] An embodiment of the first aspect of the present application provides a battery detection device including a carrier assembly, a pulsed ray source, a detector, and a first drive assembly. The carrier assembly is used to carry a battery to be tested and drive the battery to be tested to move in a first direction; the pulsed ray source is configured to emit detection rays in a pulsed manner toward the detection area of ​​the battery to be tested on the carrier assembly; the detector is arranged opposite to the pulsed ray source and is respectively located on both sides of the carrier assembly, and the detector receives the detection rays emitted by the pulsed ray source and penetrating the detection area of ​​the battery to be tested; the first drive assembly is respectively connected to the pulsed ray source and the detector, and the first drive assembly is used to drive the pulsed ray source and the detector to rotate circumferentially along the first rotation axis to collect a detection image of the detection area.

[0009] In the technical solution of the embodiment of the present application, by setting a carrying component, a pulsed radiation source and a first driving component, radiation detection can be performed on the area to be detected of the battery to be tested in a pulsed scanning manner at different positions and at different angles to obtain a detection image and use it for three-dimensional reconstruction, thereby improving the accuracy of image detection. The coordination of the pulsed radiation source with the carrying component and the first driving component can realize online detection, can cooperate with the battery production rhythm, and improve detection efficiency.

[0010] In some embodiments, the carrier assembly includes a tray and a second drive assembly; the tray is used to support one or more batteries to be tested; the second drive assembly is connected to the tray and includes a translation unit configured to enable translation of the tray along a first direction. By arranging the second drive assembly to drive the translation of the tray, the batteries to be tested can be moved into and out of the radiation range between the pulsed radiation source and the detector. This allows for automated transport and testing of the batteries to adapt to the battery production schedule and improve testing efficiency.

[0011] In some embodiments, the second drive assembly further includes a rotation unit configured to drive the tray to rotate circumferentially along a second rotation axis, the second rotation axis being the direction in which the tray surface points toward the battery under test and being perpendicular to the first direction. By configuring the second drive assembly to drive the tray to translate, the battery under test can be automatically moved into and out of the radiation range between the pulsed radiation source and the detector. This allows for automated transport and testing of the battery under test, adapting to the battery production rhythm and improving testing efficiency.

[0012] In some embodiments, the battery under test includes two first surfaces disposed opposite each other and first side surfaces connected to the two first surfaces, the first side surface being a side surface on which a short side of the first surface is located, and the second rotation axis is perpendicular to the first surface. The rotation unit is configured to drive the tray to rotate so that a projection of the first side surface on the tray surface forms a first angle α with a first direction, and satisfies 0 < α < 90°. The rotation unit can be provided to adjust the position of the battery under test so that the first side surface of the battery under test is positioned at a suitable angle within the radiation range between the pulsed radiation source and the detector, thereby adjusting the incident angle of the radiation and switching between multiple detection areas, thereby improving the quality of the captured image of the battery under test and enhancing detection efficiency.

[0013] In some embodiments, the first angle α satisfies 20°≤α≤45°. Limiting the value range of the first angle to an appropriate range can improve the imaging quality of the area to be inspected, which is conducive to improving the accuracy of subsequent image recognition and thus improving the accuracy of defect detection of the battery to be inspected.

[0014] In some embodiments, the carrier assembly includes multiple trays spaced apart along a first direction. The translation unit drives the multiple trays to translate so that the test areas of the batteries under test on two adjacent trays are simultaneously located within the radiation range between the pulsed radiation source and the detector, with the test areas located at the corners of the batteries under test. By providing multiple trays and combining them with a second drive assembly to control their movement, simultaneous testing of multiple batteries under test can be achieved, improving battery testing efficiency.

[0015] In some embodiments, the translation unit is configured to ensure that the minimum spacing L1 between the batteries under test on two adjacent trays along the first direction satisfies the following: 0 < L1 ≤ 2 mm. By controlling the movement of the trays by the translation unit, the batteries under test on adjacent trays are kept at a reasonable distance, thereby improving inspection efficiency and reducing radiation dose waste.

[0016] In some embodiments, the tray's radiation absorptivity for the test radiation is lower than the minimum radiation absorptivity of the battery under test. By setting the tray's radiation absorptivity lower than the minimum radiation absorptivity of the battery under test, the tray's impact on the test radiation can be reduced, thereby improving the accuracy of the test results.

[0017] In some embodiments, the tray is made of carbon fiber. The inclusion of carbon fiber in the tray can reduce the adverse effects of the tray's absorption of the detection radiation on the detection results, reduce the amount of processing required for subsequent image recognition, and thus improve the accuracy of the detection.

[0018] In some embodiments, the tray includes a protective layer on the side facing the battery under test, wherein the surface roughness of the protective layer is less than a preset threshold. Providing a protective layer on the side of the tray facing the battery under test can reduce wear and tear on the battery under test, more effectively mitigating damage to the battery under test during the testing process.

[0019] In some embodiments, the carrier assembly further includes a plurality of spaced-apart blocks movably connected to the tray, each of which is used to clamp the battery under test. The provision of multiple movably connected blocks allows for the clamping of batteries of varying sizes and facilitates the securement of the battery under test, thereby expanding the applicability of the battery testing device.

[0020] In some embodiments, the battery testing apparatus further includes a rotating platform, to which the pulsed radiation source and the detector are fixedly connected, and a first drive assembly drives the rotating platform to rotate circumferentially along a first rotation axis. By providing a rotating platform for fixing the pulsed radiation source and the detector, the positions of the pulsed radiation source and the detector can be maintained stable during testing, reducing time required for readjustment and improving testing efficiency and accuracy.

[0021] In some embodiments, the maximum circumferential rotation angle λ of the pulsed radiation source and the detector along the first rotation axis satisfies 45°≤λ≤180°. Limiting the maximum rotation angle of the pulsed radiation source and the detector to an appropriate range can balance image quality and detection efficiency, better adapting to battery production schedules.

[0022] In some embodiments, the detector is a CMOS detector. The use of a CMOS detector can better cooperate with the pulsed radiation source, achieve rapid imaging while taking into account imaging quality, and improve the detection efficiency of the battery under test.

[0023] In some embodiments, the maximum size of the focal spot of the pulsed radiation source is less than or equal to 80 microns. Specifically limiting the size of the focal spot can better match the detection accuracy of the battery detection device with the size of the battery under test, thereby improving detection accuracy and efficiency.

[0024] In some embodiments, the battery testing apparatus further includes an image processing unit, which is signal-coupled to the detector and configured to identify a test image captured by the detector. By configuring the image processing unit to receive the image signal generated by the detector, identify the detected image, and output the test results for the battery under test, automatic detection of internal defects in the battery under test can be achieved, thereby improving the automation and efficiency of the battery testing apparatus.

[0025] An embodiment of the second aspect of the present application provides a battery production device, which includes the battery detection device in the above embodiment.

[0026] An embodiment of the third aspect of the present application provides a battery detection method, using the above-mentioned battery detection device, the method comprising: moving the battery to be tested to a preset position; collecting multiple detection images of the detection area of ​​the battery to be tested; identifying the detection images, and determining the detection result of the battery to be tested based on the identification results.

[0027] In some embodiments, identifying the detection image includes: performing three-dimensional reconstruction on the detection image; preprocessing the slice image obtained by the three-dimensional reconstruction, capturing the vertex of the cathode and the vertex of the anode in the preprocessed image, drawing lines for the cathode and the anode, and determining the anode-cathode misalignment and the anode-cathode spacing value.

[0028] In some embodiments, determining the test result of the battery to be tested based on the identification result includes: comparing the anode-cathode misalignment amount and the anode-cathode spacing value with the set anode-cathode misalignment amount threshold and the anode-cathode spacing value threshold, respectively, and determining the test result of the battery to be tested based on the comparison result.

[0029] 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

[0030] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar components or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0031] FIG1 is a schematic structural diagram of a vehicle according to some embodiments of the present application;

[0032] FIG2 is a schematic diagram of the exploded structure of a battery according to some embodiments of the present application;

[0033] FIG3 is a schematic structural diagram of a battery detection device according to some embodiments of the present application;

[0034] FIG4 is a schematic structural diagram of a carrier assembly carrying a battery to be tested according to some embodiments of the present application;

[0035] FIG5 is a top view of FIG4;

[0036] FIG6 is a schematic structural diagram of a battery detection device according to another embodiment of the present application;

[0037] FIG7 is a schematic structural diagram of a battery detection device according to some other embodiments of the present application;

[0038] FIG8 is a structural block diagram of battery production equipment according to some embodiments of the present application;

[0039] FIG9 is a flow chart of a battery detection method according to some embodiments of the present application.

[0040] Description of reference numerals:

[0041] Vehicles 1000;

[0042] Battery 100, controller 200, motor 300;

[0043] Box body 10, first part 11, second part 12; battery cell 20;

[0044] Battery testing device 400, battery to be tested 401, first battery to be tested 401A, second battery to be tested 401B, area to be tested 4011, first surface 4012, first side surface 4013, carrying assembly 410, tray 411, first tray 411A, second tray 411B, second drive assembly 412, translation unit 4121, rotation unit 4122, block 413, pulsed ray source 420, detection ray 421, detector 430, first drive assembly 440, rotating table 450, image processing unit 460, first rotation axis 500, second rotation axis 600, battery production equipment 700, battery testing method 800. DETAILED DESCRIPTION

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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).

[0051] 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. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They 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 referred device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting the embodiments of the present application.

[0052] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connect," 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.

[0053] The position and state of the electrodes in the battery have a significant impact on the performance and safety of the battery. Taking lithium-ion batteries as an example, the distance between the cathode and cathode electrodes and the amount of misalignment of the cathode and cathode electrodes are important factors affecting the safety performance of wound cells. Regarding the distance between the cathode and cathode electrodes: During the charge and discharge process of a lithium battery, when the distance between the cathode and cathode electrodes is large, the lithium ions cannot be fully embedded in the anode channel, resulting in the accumulation of some lithium ions and the occurrence of lithium plating, which poses a greater safety risk. Therefore, it is required that the distance between the cathode and cathode electrodes in the battery should not be too large. Regarding the misalignment of the cathode and cathode electrodes: During the charge and discharge process of a lithium battery, lithium ions will repeatedly intercalate and deintercalate between the cathode and cathode electrodes. However, when lithium ions are released from the cathode but there are not enough anode channels to embed them, it is easy for lithium ions to accumulate and deposit lithium, causing certain product safety risks. Therefore, it is necessary to detect the position and state of the electrodes inside the battery to promptly detect internal defects in the battery and reduce the outflow of defective batteries.

[0054] In related technologies, X-rays are used to detect the electrodes inside the battery. For example, for laminated batteries, X-rays need to be used at a specific incident angle to detect the misalignment and gap value of the cathode and anode of the laminated battery, and then determine whether the battery is qualified. However, this method has a detection blind spot, and some defective products cannot be detected. In addition, offline CT equipment is used to rotate the battery 360° to reconstruct the image for detection, but this takes a long time and has disadvantages such as low detection efficiency and high detection cost. It cannot adapt to the production rhythm of the battery, and the battery may also cause the position state of the electrode to change during the rotation process, thereby affecting the accuracy of the battery detection results.

[0055] Based on the above considerations, in order to improve the accuracy and efficiency of battery internal defect detection, the present application proposes a battery detection device, which includes a carrying assembly, a pulsed ray source, a detector, and a first drive assembly. The carrying assembly is used to carry the battery to be tested and drive the battery to be tested to move along a first direction; the detector is arranged opposite to the pulsed ray source and is respectively located on both sides of the carrying assembly, and the detector receives the detection ray emitted by the pulsed ray source and penetrating the detection area of ​​the battery to be tested; the first drive assembly is connected to the pulsed ray source and the detector respectively, and the first drive assembly is used to drive the pulsed ray source and the detector to rotate circumferentially along the first rotation axis to collect the detection image of the area to be tested.

[0056] By arranging the carrying component, the pulsed radiation source and the first driving component to cooperate with each other, rapid multi-angle imaging of the automatically transported batteries can be achieved to realize three-dimensional reconstruction, thereby improving the detection accuracy while shortening the detection time, improving the efficiency of battery detection, and being able to adapt to the production rhythm of the battery to realize online detection.

[0057] The battery testing devices and battery production equipment disclosed in the embodiments of this application can be used in the battery manufacturing process. The tested or produced battery cells can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power supply system comprising the battery cells and batteries disclosed in this application can be used to form such electrical devices.

[0058] The present invention provides an electric device that uses a battery as a power source. The electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, etc. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0059] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0060] Please refer to Figure 1, which is a schematic structural diagram of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0061] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0062] Please refer to Figure 2, which is a schematic diagram of the exploded structure of a battery 100 provided in some embodiments of the present application. The battery 100 includes a housing 10 and battery cells 20, with the battery cells 20 housed within the housing 10. The housing 10 provides a storage space for the battery cells 20 and can have various structures. In some embodiments, the housing 10 can include a first portion 11 and a second portion 12, which overlap each other and together define a storage space for the battery cells 20. The second portion 12 can be a hollow structure with one end open. The first portion 11 can be a plate-like structure, with the first portion 11 overlapping the open side of the second portion 12, so that the first portion 11 and the second portion 12 together define a storage space. Alternatively, the first portion 11 and the second portion 12 can each be a hollow structure with one end open, with the open side of the first portion 11 overlapping the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder or a rectangular parallelepiped.

[0063] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 20 may be housed within the housing 10. Alternatively, the battery 100 may be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid connection to form a battery module, which is then connected in series, in parallel, or in a hybrid connection to form a complete battery module, and then housed within the housing 10. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 20.

[0064] Each battery cell 20 may be a secondary battery or a primary battery, and may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0065] 3-5 , FIG3 is a schematic diagram of a battery testing device 400 according to some embodiments of the present application. FIG4 is a schematic diagram of a carrier assembly 410 carrying a battery 401 under test according to some embodiments of the present application. FIG5 is a top view of FIG4 .

[0066] The present embodiment provides a battery testing device 400 comprising a carrier assembly 410, a pulsed radiation source 420, a detector 430, and a first drive assembly 440. The battery testing device 400 is used to test a battery 401 to be tested. The carrier assembly 410 is used to support the battery 401 to be tested and drive the battery 401 to be tested to move along a first direction X. The pulsed radiation source 420 is configured to emit pulsed detection radiation 421 toward a detection area 4011 of the battery 401 to be tested on the carrier assembly 410. The detector 430 is disposed opposite the pulsed radiation source 420 and is located on either side of the carrier assembly 410. The detector 430 receives detection radiation emitted by the pulsed radiation source 420 and penetrating the detection area of ​​the battery 401 to be tested. The first drive assembly 440 is connected to the pulsed radiation source 420 and the detector 430, respectively. The first drive assembly 440 is used to drive the pulsed radiation source 420 and the detector 430 to rotate along a circumferential direction M of a first rotation axis 500 to capture a detection image of the detection area.

[0067] The first rotation axis 500 is located between the driving pulsed ray source 420 and the detector 430 and is parallel to the first direction X.

[0068] The battery 401 to be tested can be the shelled battery cell 20 described in the above embodiment, or a bare cell that has not yet been shelled. The battery 401 to be tested can be a laminated battery formed by stacking electrode sheets, or a wound battery formed by stacking and winding electrode sheets. The area to be tested 4011 can be any area of ​​the battery 401 to be tested, for example, a partial area of ​​the battery 401 to be tested, or the entire area of ​​the battery 401 to be tested, and the specific area to be tested can be selected based on the purpose of the test.

[0069] The carrying assembly 410 is used to carry the battery to be tested 401. Specifically, the purpose of carrying the battery to be tested 401 can be achieved by supporting or clamping. The carrying assembly 410 can move along the first direction X, thereby driving the battery to be tested 401 to move along the first direction X, so that the area to be tested of the battery to be tested 401 moves into and out of the detection range between the pulsed radiation source 420 and the detector 430.

[0070] The pulsed radiation source 420 is a device that can emit detection radiation in a pulsed manner. It primarily comprises a radiation tube and a corresponding power supply. The detection radiation 421 can be X-rays or other radiation. The radiation tube, such as an X-ray tube or a gamma-ray tube, can emit the corresponding detection radiation 421. The pulsed radiation source 420 can be open (open tube) or closed (closed tube). In one example, the pulsed radiation source 420 is an X-ray source, and the detection radiation 421 emitted by it is X-ray. When the detection radiation 421 emitted by the pulsed radiation source 420 passes through the battery under test 401, due to the different materials of the anode and cathode plates in the battery under test 401 (the anode surface is carbon powder, which has low radiation absorption, while the cathode surface is lithium ion material, which has high radiation absorption), the different materials have different absorption rates for X-rays. Furthermore, there is a gap between the anode and cathode plates when they are wound. Therefore, the different absorption levels of X-rays can be used to detect the distance between the anode and cathode plates and the amount of misalignment between the anode and cathode plates. The pulsed ray source 420 can control the emission of the detection ray 421 according to a set pulse signal. The pulsed scanning can reduce the continuous working time of the detector 430 and increase the service life of the detector 430.

[0071] Detector 430 can be a two-dimensional flat-panel detector or an indirect flat-panel detector. In some examples, detector 430 can include a photoelectric conversion layer and a scintillator layer stacked sequentially on a substrate. The scintillator layer is located on a surface facing the pulsed radiation source 420, thereby receiving detection radiation 421 that penetrates the battery under test 401 and generating visible photons. The photoelectric conversion layer receives the visible light emitted by the scintillator layer to generate a corresponding electrical signal, thereby generating a detection image of the area under test.

[0072] The first drive assembly 440 is connected to the pulsed radiation source 420 and the detector 430, respectively, and drives the pulsed radiation source 420 and the detector 430 to rotate along a circumferential direction M about a first rotation axis 500. As shown in FIG4 , the first drive assembly 440 drives the pulsed radiation source 420 and the detector 430 to rotate about the first rotation axis 500. The first rotation axis 500 is parallel to the first direction X, and the inspection area 4011 of the battery 401 under test is also located on the first rotation axis 500. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other. Along the third direction Z, the distance between the first rotation axis 500 and the pulsed radiation source 420 is h1, and the distance between the first rotation axis 500 and the detector 430 is h2. The magnification of the detector is (h1+h2) / h1. By adjusting the positions of the pulsed radiation source 420, the first rotation axis 500, and the detector 430 along the third direction Z, the magnification of the detector can be adjusted to meet the required detection resolution.

[0073] In one example, the supporting assembly 410 carrying the battery 401 to be tested also moves in a direction parallel to the first rotation axis 500, so that the pulsed radiation source 420 and the detector 430 rotate around the detection area 4011 of the battery 401 to be tested. It is understood that during detection, the pulsed radiation source 420 and the detector 430 can rotate relative to the battery 401 to be tested. In this embodiment, the pulsed radiation source 420 and the detector 43 are configured to rotate so that the battery 401 to be tested can remain stationary during detection, thereby preventing the pole piece inside the battery 401 from changing its position due to rotational movement, thereby affecting the accuracy of the detection result. In some examples, the first drive assembly 440 can be driven by a servo motor and connected to the pulsed radiation source 420 and the detector 430 via a transmission mechanism to achieve precise control of the rotational movement of the pulsed radiation source 420 and the detector 430.

[0074] The pulsed detection ray 421 emitted by the pulsed ray source 420 is synchronized with the rotational motion of the pulsed ray source 420 and the detector 430. By collaboratively controlling the pulse signal frequency of the detection ray 421 and the rotational speed of the pulsed ray source 420 and the detector 430, a pulse signal is transmitted to the ray tube after the pulsed ray source 420 and the detector 430 rotate into position. This allows the detection ray 421 to be directed at the detection area 4011 of the battery 401 at different positions and at different incident angles. After penetrating the detection area 4011, the detection ray 421 is received by the detector 430 and a corresponding electrical signal is generated. Ultimately, multiple detection images of the detection area taken at different angles are obtained, and three-dimensional reconstruction is performed. For example, reconstruction is performed using a filtered back projection algorithm. This method can effectively remove shape artifacts, is fast, and provides good reconstruction quality. During three-dimensional reconstruction, only the region of interest (ROI), i.e., the pre-set corner slice region where the detection area 4011 is located, can be reconstructed, thereby efficiently and quickly obtaining the target slice image.

[0075] By setting up the supporting component 410, the pulsed radiation source 420 and the first driving component 440, radiation detection can be performed on the inspection area 4011 of the battery 401 to be tested in a pulsed scanning manner at different positions and angles to obtain a detection image and use it for three-dimensional reconstruction, thereby improving the accuracy of image detection. The cooperation of the pulsed radiation source 420, the supporting component 410 and the first driving component 440 can realize online detection, which can be coordinated with the battery production rhythm and improve detection efficiency.

[0076] According to some embodiments of the present application, the carrying assembly 410 includes a tray 411 and a second drive assembly 412; the tray 411 is used to carry one or more batteries 401 to be tested; the second drive assembly 412 is connected to the tray 411, and the second drive assembly 412 includes a translation unit 4121, and the translation unit 4121 is configured to drive the tray 411 to translate along the first direction X.

[0077] The tray 411 is a disc-shaped structure for holding the battery 401 to be tested. The shape of the tray 411 can match the shape of the battery 401 to be tested, for example, it can be a rectangular flat plate. The tray 411 can hold a single battery 401 to be tested, or multiple batteries 401 to be tested can be stacked on the tray. The second drive assembly 412 can be any drive assembly that can drive the tray 411 and the battery 401 to be tested to move. The translation unit 4121 can be any linear drive unit that can drive the tray 411 and the battery 401 to be tested on the tray 411 to move linearly in a specific direction. In some examples, the second drive assembly 412 can be a magnetic drive unit, for example, it can include a magnetic levitation track and a magnetic drive base. The magnetic drive base moves along the extension direction of the magnetic levitation track through magnetic drive. The tray 411 can be fixedly mounted on the magnetic drive base to translate along the first direction X under the action of the magnetic force. It is understood that the second drive assembly 412 can also be other drive structures, such as screw drive, motor drive, etc., which will not be described in detail in this embodiment.

[0078] By setting the second drive component 412 to drive the tray 411 to move horizontally, the battery 401 to be tested can be automatically moved into and out of the radiation range between the pulsed radiation source 420 and the detector 430. This can realize automatic transmission and detection of the battery 401 to be tested, adapt to the production rhythm of the battery, and improve detection efficiency.

[0079] According to some embodiments of the present application, the second drive assembly 412 further includes a rotation unit 4122, which is configured to drive the tray 411 to rotate in the circumferential direction N along the second rotation axis 600, where the second rotation axis 600 is the direction in which the surface of the tray 411 points to the battery to be tested 401 and is perpendicular to the first direction X.

[0080] The rotating unit 4122 can be a rotating structure directly driven by a power component, such as a servo motor or magnetic levitation drive, or it can convert linear motion into rotational motion via a transmission mechanism to achieve circumferential rotation N of the tray 411 along the second rotation axis 600. The second rotation axis 600 is the direction from the surface of the tray 411 toward the battery under test 401 and is perpendicular to the first direction X. In some examples, the second rotation axis 600 passes through the center of the tray 411 and is parallel to the second direction Y, which is perpendicular to the first direction X. In some examples, the battery 401 to be tested is arranged directly above the surface of the tray 411, and the second direction Y is the direction in which the second rotation axis 600 points vertically upward. The tray 411 rotates around the vertical direction, thereby driving the battery 401 to be tested to rotate around the second rotation axis 600. In this way, when there are multiple areas 4011 to be tested, for example, when the area 4011 to be tested includes the four corners of the battery 401 to be tested, each corner can be rotated and moved in turn between the pulsed radiation source 420 and the detector 430 for detection, and when the image is collected at the second corner, the detection image collected at the previous corner is three-dimensionally reconstructed to improve the detection efficiency.

[0081] By setting a rotating unit 4122 to drive the tray 411 to rotate, the battery to be tested 401 can be driven to rotate, thereby adjusting the position of the battery to be tested 401 within the range of the ray between the pulsed ray source 420 and the detector 430, thereby realizing detection of multiple areas to be detected, improving detection efficiency, and at the same time being able to more accurately capture detection images of specific areas to be detected 4011 in the battery to be tested 401, thereby improving detection accuracy.

[0082] According to some embodiments of the present application, a battery under test 401 includes two first surfaces 4012 disposed opposite each other and first side surfaces 4013 connected to the two first surfaces 4012. The first side surface 4013 is a side surface where a tab 4014 of the battery under test 401 is located. The second direction Y is perpendicular to the first surface 4012. The rotation unit 4122 is configured to drive the tray 411 to rotate so that a projection of the first surface 4012 on the surface of the tray 411 forms a first angle α with the first direction X, and satisfies 0 < α < 90°.

[0083] As shown in Figures 3-5 , the battery 401 to be tested can be a battery cell after being placed in a shell. The first surface 4012 is the shell surface facing the large surface of the electrode of the battery 401 to be tested, and the first side surface 4013 is the shell surface on the side where the electrode tab of the battery 401 to be tested is located. The battery 401 to be tested can also be a bare cell. The corresponding first surface 4012 is the surface where the large surface of the electrode is located, and the first side surface 4013 is the side surface of the bare cell on the side where the electrode tab is located, formed by the foil extending from the end of the electrode not coated with active material. In one example, the battery 401 to be tested is placed on the upper surface of the tray 411, and the area to be tested 4011 is located at a corner of the battery 401 to be tested. The first surface 4012 is parallel to the upper surface of the tray, the first side surface 4013 is perpendicular to the upper surface of the tray 411, and the first side surface 4013 is parallel to the second direction Y. The rotation unit 4122 drives the tray 411 to rotate about the second rotation axis 600, so that the projection of the first side surface 4013 on the tray forms a first angle α with the first direction X, thereby meeting the required radiation incident angle. If the inspection area 4011 is a plurality of different areas, the rotation unit 4122 can be used to sequentially move the different inspection areas 4011 into the radiation range for inspection.

[0084] Since the X-ray inspection of the battery 401 to be tested primarily involves capturing images of the corners of the battery 401 to detect parameters such as the misalignment of the cathode and anode electrodes and the spacing between the electrodes, and thereby determining whether the quality of the battery 401 to be tested meets quality requirements, the rotation unit can be provided to adjust the position of the battery 401 to be tested, so that the first side surface 4013 of the battery 401 to be tested can be positioned at an appropriate angle within the detection area between the pulsed X-ray source 420 and the detector 430. This allows for adjustment of the incident angle of the X-rays and switching between the multiple detection areas 4011, thereby improving the quality of the captured images of the battery 401 to be tested and enhancing detection efficiency.

[0085] According to some embodiments of the present application, the first angle α satisfies 20°≤α≤45°.

[0086] If the first angle α is too large or too small, the captured image of the battery 401 to be tested will contain too much information of uninteresting areas, thereby affecting the accuracy of image recognition. Specifically, limiting the first angle α to between 20° and 45° can effectively capture the detection image of the interesting area 4011 to be tested, thereby improving the imaging quality. In some examples, the first angle can be 45°.

[0087] Limiting the value range of the first angle to a suitable range can improve the imaging quality of the area to be inspected, which is beneficial to improving the accuracy of subsequent image recognition, and further improving the accuracy of defect detection of the battery 401 to be inspected.

[0088] Please refer to FIG. 6 , which is a schematic structural diagram of a battery detection device provided in some other embodiments of the present application.

[0089] According to some embodiments of the present application, the supporting assembly 410 includes a plurality of trays 411 spaced apart along a first direction X, and the translation unit 4121 drives the plurality of trays 411 to translate so that the detection areas 4011 of the batteries 401 to be tested on two adjacent trays 411 are simultaneously located within the radiation range between the pulsed radiation source 420 and the detector 430, and the detection areas 4011 are located at the corners of the batteries 401 to be tested.

[0090] The corners of the battery 401 to be tested refer to the areas located at the four corners of the first surface 4012 of the battery 401 to be tested. For laminated and wound batteries, the corners of the battery 401 to be tested can well present the position information of the cathode and anode electrodes, which is helpful for determining defects between the electrodes, such as the amount of cathode and anode electrode misalignment and the distance between the electrodes. As shown in Figure 6, multiple trays 411 include adjacent first trays 411A and second trays 411B. The first battery 401A to be tested is placed on the first tray 411A, and the second battery 401B to be tested is placed on the second tray 411B. During testing, the first tray 411A and the second tray 411B are translated to a preset position and rotated by a preset angle by the second drive assembly 412, so that a corner of the first battery 401A to be tested and a corner of the second battery 401B to be tested are simultaneously located within the radiation range between the pulsed radiation source 420 and the detector 430. In this way, the batteries to be tested on adjacent trays can be tested simultaneously. In some embodiments, multiple batteries 401 to be tested can be stacked on any tray 411. Thus, a single rotation of the pulsed radiation source 420 and the detector 430 can detect more batteries 401 to be tested. In one example, a first angle α is formed between a first side surface of a first battery 401A to be tested and a first direction X, and a first angle β is formed between a first side surface of a second battery 401B to be tested on an adjacent tray and the first direction X, where α = β = 45°.

[0091] By providing a plurality of trays 411 and controlling the movement of the trays 411 in conjunction with the second driving assembly 412 , it is possible to achieve synchronous detection of a plurality of batteries 401 to be tested, thereby improving battery detection efficiency.

[0092] According to some embodiments of the present application, the translation unit 4121 is configured to ensure that a minimum distance L1 between the batteries 401 to be tested on two adjacent trays 411 along the first direction X satisfies the following relationship: 0<L1≤2mm.

[0093] The minimum spacing L1 refers to the minimum distance along the first direction X between the outer contours of the projections of the batteries 401 under test on two adjacent trays 411. It will be understood that when the tray 411 is capable of driving the batteries 401 under test to rotate, the minimum spacing L1 refers to the minimum distance along the first direction X between the outer contours of the projections of the batteries 401 under test on the tray 411 during the rotation of the batteries under test. If the minimum spacing L1 is equal to 0, interference between the two adjacent batteries under test 401 may occur. If the minimum spacing L1 is too large, the gap between the two adjacent batteries under test 401 may be too large, resulting in some detection rays 421 not passing through the batteries under test 401 but being directly received by the detector 430, thereby wasting the detection rays.

[0094] The movement of the trays 411 is controlled by the translation unit 4121 , so that the batteries 401 to be tested on adjacent trays 411 can maintain a reasonable distance, thereby improving the detection efficiency and reducing the waste of radiation dose.

[0095] According to some embodiments of the present application, the radiation absorption rate of the tray 411 to the detection radiation 421 is less than the minimum radiation absorption rate of the battery to be tested 401 to the detection radiation 421 .

[0096] When the detection ray 421 penetrates a substance, a portion of it will be absorbed, resulting in ray attenuation. The ray absorptivity refers to the degree of absorption of the ray by a certain material per unit thickness. The battery 401 to be tested always contains a variety of different materials, and different materials have different degrees of absorption of the detection ray, and the corresponding ray absorptivity is also different. It is based on this that the detector 430 can present the position information of the different materials of the battery 401 to be tested from the received detection ray 421. The minimum ray absorptivity of the battery 401 to be tested for the detection ray 421 refers to the ray absorptivity corresponding to the material in the battery 421 to be tested that has the lowest absorption rate of the detection ray 421 when the detection ray 421 penetrates the battery 421 to be tested.

[0097] The absorptivity of the tray 411 to the test beam 421 is primarily related to the material used. Different materials have different absorptivity rates for the test beam 421. Because the tray 411 is positioned behind the test battery 401, the test beam 421 that penetrates the test battery 401 often also needs to penetrate the tray 411. By selecting an appropriate material, the tray 411's absorptivity to the test beam 421 can be reduced to less than the minimum absorptivity of the test battery 401.

[0098] By setting the radiation absorptivity of the tray 411 to be lower than the minimum radiation absorptivity of the battery 401 to be tested for the detection radiation 421, the influence of the tray 411 on the detection radiation 421 can be reduced. In other words, the tray 411 can be more easily distinguished from the battery 401 to be tested in the detection image, thereby reducing the influence of the tray 411 on the detection results in the detection image, thereby improving the accuracy of the detection results.

[0099] According to some embodiments of the present application, the material of the tray 411 includes carbon fiber.

[0100] Carbon fiber is highly translucent to X-rays, with an X-ray absorption rate per unit thickness of only 1.4% / mm, far lower than that of metal materials like aluminum. Tray 411 can be made entirely or partially of carbon fiber, or a carbon fiber composite material to balance other performance aspects.

[0101] The material of the tray 411 including carbon fiber can reduce the absorption of the detection radiation by the tray 411 , thereby reducing the adverse effect of the tray 411 on the detection result, reducing the processing load of subsequent image recognition, and thus improving the accuracy of the detection.

[0102] According to some embodiments of the present application, the tray 411 includes a protective layer located on a surface of a side facing the battery to be tested 401 , and the surface roughness of the protective layer is less than a preset threshold.

[0103] The protective layer can be obtained by processing the surface of the side of the tray 411 facing the battery to be tested, that is, for example, polishing the surface of the side of the tray 411 facing the battery to be tested so that the surface roughness there is less than a preset threshold value to meet the roughness requirement. The protective layer can also be obtained by applying an additional layer of material to the surface of the side of the tray 411 facing the battery to be tested to form a film layer, such as spraying or pasting a Teflon material layer, thereby forming a protective layer with a surface roughness less than a preset threshold value. The preset threshold value can be selected according to actual needs. For example, the surface roughness of the position where the non-protective layer is located can be selected, that is, the surface roughness of the protective layer is less than the surface roughness of the position where the non-protective layer is located; other appropriate thresholds can also be selected as needed to meet the protection requirements for the battery.

[0104] By providing a protective layer on the surface of the tray 411 facing the battery 401 to be tested, the wear of the tray 411 on the battery 401 to be tested can be reduced, and the damage to the battery 401 to be tested during the testing process can be more effectively alleviated.

[0105] According to some embodiments of the present application, the carrying assembly 410 further includes a plurality of stoppers 413 movably connected to the tray 411 and spaced apart. The plurality of stoppers 413 are used to clamp the battery 401 to be tested.

[0106] The stopper 413 can be arranged on a side surface of the tray 411 facing the battery 401 to be tested in a movable manner, for example, by providing a slide and movably inserting the stopper 413 into the slide to achieve the movable connection. In this way, the battery 401 to be tested can be clamped between the multiple stoppers 413, thereby fixing the battery 401 to be tested so as to drive the battery 401 to be tested to move or rotate. In some examples, the distance between the multiple stoppers 413 can be set to be adjustable so as to accommodate batteries 401 to be tested of different sizes. The spacing between two stoppers 413 located on opposite sides of the battery 401 to be tested is set to be larger than the corresponding size of the battery 401 to prevent damage to the battery to be tested during clamping. It is understandable that an elastic buffer can be provided on the side of the stopper 413 facing the battery 401 to fill the gap between the stopper 413 and the battery 401 to be tested and protect the battery 401 to be tested.

[0107] By providing a plurality of movable blocks 413 , the clamping requirements of batteries 401 to be tested of different sizes can be met, and the batteries 401 to be tested can be fixed more conveniently, thereby improving the application range of the battery testing device 400 .

[0108] Please refer to FIG. 7 , which is a schematic structural diagram of a battery detection device 400 provided in some embodiments of the present application.

[0109] According to some embodiments of the present application, the battery detection device 400 further includes a rotating table 450 , to which the pulsed radiation source 420 and the detector 430 are fixedly connected, and the first driving assembly 440 drives the rotating table 450 to rotate along the circumferential direction M of the first rotation axis 500 .

[0110] The rotating platform 450 can be any hollow shape, such as a ring, to allow the second drive assembly 412 to drive the tray 411 and the battery under test 401 through the middle. The pulsed radiation source 420 and the detector 430 are both fixedly connected to the rotating platform 450 and fixed in relative position. This eliminates the need for the first drive assembly 440 to adjust the position of the pulsed radiation source 420 and the detector 430 when driving the rotating platform 450. The first drive assembly 440 can be a servo motor that directly or indirectly drives the rotating platform 450 to rotate, or it can be another type of power component.

[0111] By providing a rotating table for fixing the pulsed ray source 420 and the detector 430, the stability of the positions of the pulsed ray source 420 and the detector 430 can be maintained during detection, saving time for readjusting the positions and improving detection efficiency and accuracy.

[0112] According to some embodiments of the present application, a maximum rotation angle λ of the pulsed ray source 420 and the detector 430 along the circumferential direction M of the first rotation axis 500 satisfies 45°≤λ≤180°.

[0113] The first drive assembly 440 can drive the pulsed ray source 420 and the detector 430 to rotate within a certain angle range along the circumferential direction M of the first rotation axis 500. The maximum angle λ refers to the maximum value of the angular range that can be rotated. The value of the maximum angle λ can be set according to the detection requirements. The smaller the maximum angle λ, the smaller the angular range in which the pulsed ray source 420 and the detector 430 can rotate along the circumferential direction M of the first rotation axis 500. For some thicker batteries to be tested or a large number of batteries to be tested, some areas to be tested may exceed the detection range and cannot be detected. The larger the maximum angle λ, the larger the angular range that can be rotated, but it will also consume more detection time, which is not conducive to improving detection efficiency. In some examples, the maximum angle λ of the pulsed ray source 420 and the detector 430 can be 90°, for example, from -45° to 45° (with the plane where the first surface 4012 of the battery to be tested 401 is located as the reference plane, the angle formed below the reference plane is negative, and the angle formed above the reference plane is positive).

[0114] In this embodiment, the maximum rotation angle of the pulsed radiation source 420 and the detector 430 is limited to a suitable range, which can take into account both the image quality and detection efficiency of the detection imaging and better adapt to the production rhythm of the battery.

[0115] According to some embodiments of the present application, the detector is a complementary metal-oxide semiconductor (CMOS) detector.

[0116] In this embodiment, the photodiode array of the CMOS detector is made of crystalline silicon using the CMOS process. Each pixel in the CMOS detector has an amplifier that amplifies the signal before transmission. As a result, the signal level is significantly higher than the noise level, resulting in a high signal-to-noise ratio (SNR). This results in higher quantum detection efficiency for the same radiation dose. Furthermore, due to the active pixels, the CMOS detector offers the advantages of strong transmitted signals and fast readout speeds.

[0117] The selection of a CMOS detector can better cooperate with a pulsed radiation source, achieve rapid imaging while taking imaging quality into consideration, and improve the detection efficiency of the battery 401 to be tested.

[0118] According to some embodiments of the present application, the maximum size of the focal spot of the pulsed ray source 420 is less than or equal to 80 micrometers.

[0119] The focal size of a X-ray source refers to the size of the focal point along a certain direction parallel to the plane where the focal point lies. When other conditions are the same, the smaller the focal point, the higher the resolution and the better the imaging quality. Common methods for measuring the focal size of X-ray sources are divided into direct and indirect methods. The direct method refers to directly observing the shape and size of the focal point, such as the pinhole method. The indirect method calculates the focal size by observing the point spread function or line spread function caused by the focal size, including the knife edge method, the slit method, and the ball target method. It can also be tested by referring to the methods specified in relevant measurement standards, such as the measurement methods listed in GB / T26834-2011.

[0120] The focal spot size is directly related to the image resolution of the battery detection device. Specifically limiting the focal spot diameter can better match the detection accuracy of the battery detection device with the size of the battery to be tested, thereby improving the detection accuracy and efficiency.

[0121] According to some embodiments of the present application, the battery detection device 400 further includes an image processing unit 460 , which is signal-connected to the detector 430 for identifying the detection image captured by the detector 430 .

[0122] Image processing unit 460 can be a computer device that receives electrical signals from detector 430 to restore an image of the object being tested. Image processing unit 460 can also be pre-set with a corresponding image recognition algorithm. By recognizing the detection image, it can obtain corresponding detection results and, based on the detection results, determine whether the battery under test 401 has an abnormality. In one example, image processing unit 460 can recognize the detection image to obtain parameters such as the misalignment of the cathode and anode plates and / or the distance between the cathode and anode plates within the battery under test 401, compare these parameters with preset thresholds, and output a corresponding detection result based on the comparison result.

[0123] By setting up an image processing unit 460 to receive the image signal generated by the detector 430 and identifying the detected image to output the detection result of the battery to be tested 401, automatic detection of internal defects of the battery to be tested can be achieved, thereby improving the automation level and detection efficiency of the battery detection device.

[0124] Please refer to FIG8 , which is a structural block diagram of a battery production device 700 provided in some embodiments of the present application.

[0125] An embodiment of the present application provides a battery production device 700 , which includes the battery detection device 400 in the above embodiment.

[0126] The battery production equipment 700 can be equipment for producing bare cells or battery cells, or it can be equipment for producing battery packs or battery groups.

[0127] The battery production equipment 700 includes a battery testing device 400, which allows non-destructive testing of the battery 401 to be tested during its production process, timely discovering defects inside the battery 401 to be tested, thereby eliminating unqualified batteries 401 to be tested and improving the quality of the batteries 401 flowing out.

[0128] The battery detection device of the present application is further described below in conjunction with one or more specific embodiments.

[0129] 3 to 7 , the battery testing device 400 includes a carrier assembly 410, a pulsed radiation source 420, a detector 430, a first driving assembly 440, a rotating stage 450, and an image processing unit 460. The battery testing device 400 is used to test a battery 401 to be tested. The carrying assembly 410 is used to carry the battery to be tested 401 and drive the battery to be tested 401 to move along the first direction X; the pulsed radiation source 420 is configured to emit pulsed detection radiation 421 to the area to be tested 4011 of the battery to be tested 401 on the carrying assembly 410; the detector 430 is arranged opposite to the pulsed radiation source 420 and is respectively located on both sides of the carrying assembly 410. The detector 430 receives the detection radiation emitted by the pulsed radiation source 420 and penetrating the area to be tested of the battery to be tested 401; the first driving assembly 440 is respectively connected to the pulsed radiation source 420 and the detector 430. The first driving assembly 440 is used to drive the pulsed radiation source 420 and the detector 430 to rotate along the circumferential direction M of the first rotation axis 500 to collect a detection image of the area to be tested.

[0130] In some examples, the battery to be tested 401 may be a laminated battery, and the area to be inspected 4011 may be a corner of the battery to be tested 401 .

[0131] In some examples, the support assembly 410 includes a tray 411, a second drive assembly 412, and a plurality of blocks 413. The blocks 413 are movably connected to the tray 411 and spaced apart. The tray 411 is used to support one or more batteries 401 under test. The tray 411 is made of carbon fiber or a carbon fiber composite material. The plurality of blocks 413 are used to clamp the batteries 401 under test.

[0132] In some examples, the second drive assembly 412 is connected to the tray 411, and the second drive assembly 412 includes a translation unit 4121 and a rotation unit 4122. The translation unit 4121 is configured to drive the tray 411 to translate along the first direction X, and the rotation unit 4122 is configured to drive the tray 411 to rotate along the circumferential direction N of the second rotation axis 600, so that the projection of the first side surface 4012 of the battery to be tested 401 on the surface of the tray 411 forms a first angle α of 45° with the first direction X.

[0133] In some examples, the pulsed radiation source 420 and the detector 430 are fixedly connected to the rotating stage 450, and the first drive assembly 440 drives the rotating stage 450 to rotate along the circumferential direction M of the first rotation axis 500. The maximum angle λ of the pulsed radiation source 420 and the detector 430 along the circumferential direction M of the first rotation axis 500 satisfies 45°≤λ≤180°.

[0134] In some examples, the detector is a CMOS detector, and the maximum size of the focal spot of the pulsed radiation source 420 is less than or equal to 80 microns.

[0135] In some examples, the image processing unit 460 is signal-connected to the detector 430 for identifying the detection image acquired by the detector 430 .

[0136] Please refer to FIG. 9 , which is a flow chart of a battery defect detection method 800 according to some embodiments of the present application.

[0137] An embodiment of the present application provides a battery defect detection method 800 , which can be implemented by the battery detection device 400 in the above embodiment.

[0138] In some examples, the battery defect detection method 800 may include the following steps:

[0139] Step S810 : Fix the battery 401 to be tested to the carrier assembly 410 . By moving the positions of the stoppers 413 on the carrier assembly 410 , the battery 401 to be tested is clamped between the multiple stoppers 413 .

[0140] Step S820: Move the battery under test 401 to a preset position. This step includes controlling the translation unit 4121 to move the battery under test 401 to a designated position between the pulsed radiation source 420 and the detector 430, and controlling the rotation unit 4122 to rotate the battery under test 401 until the first side surface 4013 of the battery under test 401 forms an angle of 45° with the first direction X.

[0141] Step S830: Acquire test images. The pulsed radiation source 420 and detector 430 are controlled to rotate and scan, capturing multiple test images of the test area 4011. The first drive assembly 440 drives the pulsed radiation source 420 and detector 430 to rotate about the first rotation axis 500, with a rotation angle between -45° and 45°. The frequency and number of acquisitions can be set based on the number and thickness of the batteries 401 to be tested. The radiation source is controlled by a pulse signal to emit test radiation, which is then received by the detector 430 to form a test image.

[0142] Step S840: Identify the detection image. Specifically including:

[0143] 3D Reconstruction: The inspection image acquired in step S830 is reconstructed in 3D using the filtered back projection (FBP) algorithm. This method effectively removes shape artifacts, is fast, and provides high-quality reconstruction. By reconstructing only the region of interest (ROI), i.e., the pre-set corner slices, this method can quickly and efficiently obtain the target slice image.

[0144] Image preprocessing: Preprocess the slices obtained from the 3D reconstruction to facilitate point and line recognition in the subsequent algorithms. This preprocessing step includes region of interest (ROI) extraction and contrast enhancement. ROI extraction involves cropping the slices to the surrounding, non-informative area, improving image processing efficiency and reducing the image size. Contrast enhancement enhances the grayscale contrast in the image, highlighting the lines between the cathode and anode electrodes.

[0145] Algorithm recognition: A deep learning model is used to accurately capture the cathode and anode vertices in images and accurately draw lines between them. First, test images of some batteries 401 to be tested are collected. These pre-processed images are calibrated to form a training dataset. The calibrated images are then trained using a deep learning model to accurately capture the cathode and anode vertices and accurately draw lines. The pre-processed test images are then recognized to determine the anode-cathode misalignment and the distance between the anode and cathode.

[0146] Step S850: Threshold determination.

[0147] Threshold determination is performed by reading the coordinates of the anode and cathode vertices identified by the algorithm, calculating the difference in their ordinates, and multiplying it by the actual size of the calibrated pixel to obtain the anode and cathode misalignment. At the same time, a line is drawn by reading the anode and cathode electrode positions identified by the algorithm, calculating the difference in their abscissas, and multiplying it by the actual size of the calibrated pixel to obtain the anode and cathode spacing value. This is then compared with the set anode and cathode misalignment threshold and anode and cathode spacing value threshold. Any layer of measured value less than the set threshold is judged as NG, otherwise it is judged as OK. The NG type is also marked on the image. The NG type can be NG for anode and cathode misalignment, NG for anode and cathode spacing, or NG for all. In some examples, the threshold for determining anode and cathode misalignment is 0.1mm. Products greater than 0.1mm are OK, and products less than 0.1mm are NG. The threshold for determining anode and cathode spacing is 120 microns (μm). Products greater than 120μm are NG, and products less than 120μm are OK.

[0148] In some examples, step S860 may be further executed after step S850: data saving and uploading.

[0149] The algorithm automatically stores the anode-cathode misalignment and spacing values ​​identified by the algorithm into a table for output. NG images and data are uploaded to the cloud system for easy review and data traceability. The storage period for test images and tables can be customized according to user needs.

[0150] 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 detection device, comprising: A carrying assembly, used for carrying a battery to be tested and driving the battery to be tested to move along a first direction; A pulsed ray source is configured to emit detection rays in a pulsed manner toward a detection area of ​​the battery to be tested on the carrier assembly; A detector is arranged opposite to the pulsed ray source and is respectively located on both sides of the carrier assembly, and receives the ray emitted by the ray source and penetrating the to-be-tested area of ​​the to-be-tested battery; as well as A first driving component is connected to the pulsed ray source and the detector, respectively. The first driving component is used to drive the pulsed ray source and the detector to rotate circumferentially along a first rotation axis to collect a detection image of the area to be detected. The first rotation axis is parallel to the first direction.

2. The battery testing device according to claim 1, wherein: The bearing assembly comprises: A tray, used for carrying one or more batteries to be tested; and The second driving assembly is connected to the tray, and the second driving assembly includes a translation unit, and the translation unit is configured to drive the tray to translate along the first direction.

3. The battery testing device according to claim 2, wherein: The second driving assembly further includes a rotating unit, which is configured to drive the tray to rotate circumferentially along a second rotation axis, wherein the second rotation axis is a direction in which the surface of the tray points to the battery to be tested and is perpendicular to the first direction.

4. The battery testing device according to claim 3, wherein: The battery to be tested comprises two first surfaces arranged opposite to each other and first side surfaces respectively connected to the two first surfaces, the first side surface is a side surface where the tab of the battery to be tested is located, and the second rotation axis is perpendicular to the first surface; The rotating unit is configured to drive the tray to rotate so that a projection of the first side surface on a surface of the tray forms a first angle α with the first direction and satisfies 0<α<90°.

5. The battery testing device according to claim 4, wherein: The first angle α satisfies 20°≤α≤45°.

6. The battery testing device according to any one of claims 2 to 5, wherein: The supporting assembly includes a plurality of trays spaced apart along the first direction, and the translation unit drives the plurality of trays to translate so that the inspection areas of the batteries to be tested on two adjacent trays are simultaneously located within the radiation range between the pulsed radiation source and the detector, and the inspection areas are located at corners of the batteries to be tested.

7. The battery testing device according to claim 6, wherein: The translation unit is configured to ensure that a minimum distance L1 between the batteries to be tested on two adjacent trays along the first direction satisfies: 0<L1≤2mm.

8. The battery testing device according to any one of claims 2 to 7, wherein: The absorption rate of the tray to the detection rays is less than the minimum absorption rate of the battery to be tested to the detection rays.

9. The battery detection device according to claim 8, characterized in that: The material of the tray includes carbon fiber.

10. The battery testing device according to any one of claims 2 to 9, wherein: The tray comprises a protective layer on a surface of a side facing the battery to be tested, and the surface roughness of the protective layer is less than a preset threshold.

11. The battery testing device according to any one of claims 2 to 10, wherein: The bearing assembly further comprises a plurality of stoppers movably connected to the tray and arranged at intervals, wherein the plurality of stoppers are used to clamp the battery to be tested.

12. The battery testing device according to any one of claims 2 to 11, wherein: The battery detection device further includes a rotating table, the pulsed ray source and the detector are fixedly connected to the rotating table, and the first driving assembly drives the rotating table to rotate circumferentially along the first rotation axis.

13. The battery testing device according to any one of claims 1 to 12, wherein: A maximum angle λ of circumferential rotation of the pulsed ray source and the detector along the first rotation axis satisfies 45°≤λ≤180°.

14. The battery testing device according to any one of claims 1 to 13, wherein: The detector is a CMOS detector.

15. The battery testing device according to any one of claims 1 to 14, wherein: The maximum size of the focus of the pulsed ray source is less than or equal to 80 microns.

16. The battery testing device according to any one of claims 1 to 15, wherein: The battery detection device also includes an image processing unit, The image processing unit is connected to the detector signal to identify the detection image acquired by the detector.

17. A battery production equipment, comprising the battery testing device according to any one of claims 1 to 16.

18. A battery detection method, using the battery detection device according to any one of claims 1 to 16, the method comprising: Move the battery to be tested to the preset position; Collecting a plurality of detection images of the detection area of ​​the battery to be tested; identifying the detection image, The detection result of the battery to be tested is determined according to the identification result.

19. The battery detection method according to claim 18, wherein: The identifying the detection image comprises: Performing three-dimensional reconstruction on the detection image; Preprocess the slice images obtained by 3D reconstruction. The vertices of the cathode and the anode in the preprocessed image are captured, as well as the lines drawn for the cathode and the anode, and the misalignment amount of the cathode and anode and the distance between the cathode and anode are determined.

20. The battery detection method according to claim 19, wherein: Determining the detection result of the battery to be tested according to the identification result includes: The anode-cathode misalignment amount and the anode-cathode spacing value are compared with the set anode-cathode misalignment amount threshold and anode-cathode spacing value threshold, respectively. The detection result of the battery to be tested is determined according to the comparison result.

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