Method for detecting gap between cathode and anode of battery cell and method for detecting gap between cathode and anode of battery cell

Abstract

The present application discloses a method for detecting the gap between the cathode and cathode of a battery cell and a method for detecting the gap between the cathode and cathode of a battery cell, and belongs to the field of batteries. The method for detecting the gap between the cathode and cathode of a battery cell comprises: obtaining a tomographic image corresponding to a target position in the battery cell to be tested based on image frames of the battery cell to be tested at multiple different angles; extracting at least one cathode feature and at least one anode feature based on the grayscale value of the tomographic image and the physical properties of the electrode; calculating the distance between adjacent cathode features and anode features to obtain the target gap distance. The method for detecting the gap between the cathode and cathode of a battery cell of the present application can detect the gap value between the cathode and cathode pieces at all corners of the entire battery cell, has high detection precision and detection accuracy, and has high detection efficiency, and effectively ensures the safety of the battery cell.

Description

Technical Field

[0001] The present application belongs to the field of batteries, and in particular, relates to a method for detecting the gap between cathode and anode of a battery cell and a method for detecting a battery cell. Background Art

[0002] As the electric vehicle market continues to improve and mature, users have put forward higher requirements for battery safety. In related technologies, the detection of the gap between the cathode and anode plates of battery cells usually uses X-Ray equipment to detect the gap value in one direction at the corner of the wound battery cell or uses industrial CT to perform a small number of random inspections. However, this method has poor detection accuracy and comprehensiveness, and low detection efficiency. Summary of the invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a method for detecting the gap between the cathode and cathode of a battery cell and a method for detecting a battery cell, which can detect the gap value between the cathode and cathode of the entire battery cell at all corners, has high detection precision and detection accuracy, and has high detection efficiency, effectively ensuring the safety of the battery cell.

[0004] In a first aspect, the present application provides a method for detecting the gap between the cathode and anode of a battery cell, the method comprising: obtaining a tomographic image corresponding to a target position in the battery cell to be tested based on image frames acquired at multiple different angles of the battery cell to be tested; the image frame comprises image features of the electrode piece of the battery cell to be tested at a bend; based on the grayscale value of the tomographic image and the physical properties of the electrode, extracting at least one cathode feature and at least one anode feature; calculating the distance between adjacent cathode features and anode features to obtain a target gap distance.

[0005] According to the method for detecting the gap between the cathode and anode of a battery cell of the present application, different features such as cathode features, anode features and gap features are distinguished by the grayscale value of the tomographic image of the battery cell to be tested and the physical properties of the electrode. The gap distance of the battery cell to be tested is calculated based on the pixel distance between the extracted cathode features and the anode features. The gap value of the cathode and anode pieces at all corners of the entire battery cell can be detected, and the detection precision and accuracy are high, and the detection efficiency is high, which effectively ensures the safety of the battery cell.

[0006] According to one embodiment of the present application, the extraction of at least one cathode feature and at least one anode feature based on the grayscale value of the tomographic image and the physical characteristics of the electrode includes: extracting multiple first feature regions and at least one second feature region based on the grayscale value; obtaining the width of each of the first feature regions; and classifying the first feature regions based on the physical characteristics of the electrode and the width to obtain the cathode feature and the anode feature.

[0007] According to the anode-cathode gap detection method of the battery cell of the present application, the anode-cathode characteristics and the gap characteristics are distinguished by grayscale values ​​to extract the first characteristic area, and then the cathode characteristics and the anode characteristics are distinguished based on the thickness difference of the first characteristic area. The operation is simple and fast, the processing efficiency is high, and it has high extraction precision and accuracy, which helps to improve the accuracy of subsequent gap detection results.

[0008] According to one embodiment of the present application, the distance between adjacent cathode features and anode features is calculated to obtain a target gap distance, including: emitting a target ray in all directions with the midpoint of the battery cell to be tested as the center; extracting the intersection points between the target ray and the cathode feature and the anode feature; and determining the length between adjacent intersection points as the target gap distance.

[0009] According to the method for detecting the gap between the cathode and anode of a battery cell of the present application, a target ray is emitted in all directions with the midpoint of the battery cell to be tested as the center, and the gap between each adjacent cathode and anode is calculated based on the length between the intersection of the target ray and the cathode feature and the anode feature. This method has a high calculation granularity and is capable of detecting the gap value between the cathode and anode pieces at all corners of the entire battery cell, further improving the accuracy and authenticity of the calculation results.

[0010] According to one embodiment of the present application, the method of acquiring a tomographic image corresponding to a target position in the battery cell to be tested based on image frames acquired at multiple different angles of the battery cell to be tested includes: performing three-dimensional reconstruction on the image frames acquired at multiple different angles of the battery cell to be tested to acquire the tomographic image.

[0011] According to the method for detecting the anode-cathode gap of a battery cell of the present application, by performing three-dimensional reconstruction on multiple image frames of the battery cell to be tested taken at multiple different angles, the three-dimensional information of the battery cell to be tested can be restored to retain more image features, thereby improving the precision and accuracy of the final tomographic image.

[0012] According to one embodiment of the present application, the image frames of the battery cell to be tested acquired at multiple different angles are three-dimensionally reconstructed to obtain the tomographic image, including: three-dimensionally reconstructing the image frames at the multiple different angles to obtain a first image; performing feature extraction on the first image based on grayscale values ​​to locate the contour edge of the battery cell to be tested; and performing image cutting processing on the first image based on the contour edge to obtain the tomographic image corresponding to the target position.

[0013] According to one embodiment of the present application, the first image is cut based on the contour edge to obtain the tomographic image corresponding to the target position, including: taking the contour edge as the starting point, moving the target distance toward the center of the battery cell to be tested to determine the first contour line; and the first image is cut based on the first contour line to obtain the tomographic image.

[0014] According to the anode-cathode gap detection method of the battery cell of the present application, by performing image cutting processing on the reconstructed first image, the anode-cathode alignment can be improved, the interference features around the contour edge can be removed, clearer anode-cathode features can be displayed, and the imaging quality can be improved, thereby improving the precision and accuracy of subsequent anode-cathode gap detection.

[0015] According to one embodiment of the present application, before acquiring the tomographic image corresponding to the target position in the battery cell to be tested based on the acquired image frames of the battery cell to be tested at multiple different angles, the method further includes: controlling the field of view angle of the imaging system to be toward at least a partial area of ​​the pole piece of the battery cell to be tested at the bend; controlling the imaging system to rotate based on a first angle, and controlling the imaging system to capture the image of the battery cell to be tested at least once at each rotation angle to obtain the image frames at the multiple different angles.

[0016] According to one embodiment of the present application, before acquiring a tomographic image corresponding to a target position in the battery cell to be tested based on the acquired image frames of the battery cell to be tested at multiple different angles, the method includes: controlling the field of view angle of the imaging system to be toward the two battery cells to be tested; wherein the two battery cells to be tested are placed diagonally, and at least a portion of the pole pieces of each battery cell to be tested at the bend is located within the field of view angle; controlling the imaging system to collect the image frames at multiple different angles, the image frames including image features of the pole pieces of the two battery cells to be tested at the bend.

[0017] In a second aspect, the present application provides a method for detecting a battery cell, the method comprising: determining a target gap distance of the battery cell to be tested based on the anode-cathode gap detection method of the battery cell as described in the first aspect; and determining that the battery cell to be tested is unqualified when the target gap distance is greater than a safety distance threshold.

[0018] According to the battery cell detection method of the present application, different features such as cathode features, anode features and gap features are distinguished by the grayscale value of the tomographic image, the gap distance between the anode and cathode of the battery cell to be tested is calculated based on the extracted cathode features and anode features, and safety detection is performed based on the gap distance and product specifications. The method has high detection accuracy and efficiency, and effectively ensures the safety of the battery cell.

[0019] In a third aspect, the present application provides a device for detecting the gap between the cathode and anode of a battery cell, the device comprising: a first processing module, for acquiring a tomographic image corresponding to a target position in the battery cell to be tested based on image frames of the battery cell to be tested acquired at multiple different angles; the image frame comprises image features of the electrode piece of the battery cell to be tested at a bend; a second processing module, for extracting at least one cathode feature and at least one anode feature based on the grayscale value of the tomographic image and the physical properties of the electrode; and a third processing module, for calculating the distance between adjacent cathode features and anode features to obtain a target gap distance.

[0020] According to the anode-cathode gap detection device of the battery cell of the present application, different features such as cathode features, anode features and gap features are distinguished by the grayscale value of the tomographic image of the battery cell to be tested and the physical properties of the electrode, and the gap distance of the battery cell to be tested is calculated based on the pixel distance between the extracted cathode features and the anode features. The full-corner anode-cathode gap value of the entire battery cell can be detected, and the detection precision and accuracy are high, and the detection efficiency is high, which effectively ensures the safety of the battery cell.

[0021] In a fourth aspect, the present application provides a detection system, comprising:

[0022] An imaging system, wherein the field of view of the imaging system is oriented toward a target angle of the battery cell to be tested, the imaging system comprising a micro-focus X-ray source and a flat-panel detector electrically connected to the micro-focus X-ray source, the flat-panel detector being used to convert the X-rays emitted by the micro-focus X-ray source into electrical signals and generate image frames of the battery cell to be tested at multiple different angles;

[0023] A processing module, the processing module is electrically connected to the imaging system, and is used to execute the method for detecting the cathode and anode gap of a battery cell as described in the first aspect.

[0024] In a fifth aspect, the present application provides a battery cell, which determines the cathode and anode gap based on the cathode and anode gap detection method of the battery cell as described in the first aspect, or performs detection based on the battery cell detection method as described in the second aspect.

[0025] In a sixth aspect, the present application provides an electrical device, wherein the electrical device comprises the battery cell as described in the fifth aspect.

[0026] In the seventh aspect, the present application provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for detecting the anode and cathode gap of a battery cell as described in the first aspect or the method for detecting a battery cell as described in the second aspect.

[0027] In an eighth aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the method for detecting the anode and cathode gap of a battery cell as described in the first aspect or the method for detecting a battery cell as described in the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0029] Figure 1 This is one of the flow charts of the method for detecting the gap between the cathode and anode of a battery cell provided in an embodiment of the present application;

[0030] Figure 2 This is one of the principle schematic diagrams of the method for detecting the gap between the cathode and anode of a battery cell provided in an embodiment of the present application;

[0031] Figure 3 This is the second principle schematic diagram of the method for detecting the gap between the cathode and anode of a battery cell provided in an embodiment of the present application;

[0032] Figure 4 This is the third principle schematic diagram of the method for detecting the gap between the cathode and anode of a battery cell provided in an embodiment of the present application;

[0033] Figure 5 It is a schematic diagram of the results of the anode-cathode gap detection method of a battery cell provided in an embodiment of the present application;

[0034] Figure 6 This is the second flow chart of the method for detecting the gap between the cathode and anode of a battery cell provided in an embodiment of the present application;

[0035] Figure 7 It is a structural schematic diagram of a cathode-cathode gap detection device for a battery cell provided in an embodiment of the present application;

[0036] Figure 8 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application;

[0037] Fig. 9 It is a schematic diagram of the flow of a battery cell detection method provided in an embodiment of the present application;

[0038] Fig.10 It is a schematic diagram of the structure of a battery cell detection device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0040] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0041] In conjunction with the accompanying drawings, the anode-cathode gap detection method of a battery cell, the cathode-cathode gap detection device of a battery cell, the detection system and the readable storage medium provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.

[0042] The method for detecting the gap between the cathode and anode of a battery cell may be applied to a terminal, and may be specifically executed by hardware or software in the terminal.

[0043] The embodiment of the present application provides a method for detecting the anode-cathode gap of a battery cell. The execution subject of the method for detecting the anode-cathode gap of a battery cell can be a detection system, an electronic device, or a cathode-cathode gap detection of a battery cell or a functional module or functional entity in an electronic device that can implement the cathode-cathode gap detection method of a battery cell. The electronic devices mentioned in the embodiment of the present application include but are not limited to mobile phones, tablet computers, computers, cameras, and wearable devices. The method for detecting the anode-cathode gap of a battery cell provided in the embodiment of the present application is described below by taking an electronic device as an execution subject as an example.

[0044] The inventors found that the penetration rate of electric vehicles in the market continues to rise, and they have gradually become the mainstream models in the automobile market. As the new energy market expands, the demand for power batteries is rapidly increasing, and as the market continues to improve and mature, consumers have put forward higher requirements for battery safety. The gap value between the anode and cathode plates of the battery is a key control item in the battery manufacturing process, because during the charging and discharging process of lithium-ion batteries, lithium ions will shuttle back and forth between the anode and cathode plates, and realize deintercalation on the anode and cathode. When the gap value between the plates is too large, the released lithium ions cannot quickly reach the surface of the plates to complete the embedding, which is easy to cause the accumulation of lithium ions and the generation of lithium dendrites, thus posing a safety risk. In the related art, the detection of the gap between the anode and cathode plates of the battery cell usually uses X-Ray equipment to detect the gap value in one direction of the corner of the wound battery cell or uses industrial CT to perform a small number of random inspections. However, this method has problems such as poor detection accuracy and comprehensiveness in detecting the gap value of the anode and cathode plates at all corners of the entire battery cell, and low detection efficiency.

[0045] Based on the above considerations, in order to solve the problems of poor detection accuracy and comprehensiveness and low detection efficiency in detecting the gap value of the cathode and anode pieces of the entire battery cell at all corners, the inventors have designed a method for detecting the gap between the cathode and anode pieces of a battery cell after in-depth research, including: based on the acquired image frames of the battery cell to be tested at multiple different angles, obtaining a tomographic image corresponding to the target position in the battery cell to be tested; the image frame includes image features of the electrode piece of the battery cell to be tested at the bend; based on the grayscale value of the tomographic image and the physical properties of the electrode, extracting at least one cathode feature and at least one anode feature; calculating the distance between adjacent cathode features and anode features to obtain the target gap distance.

[0046] In the anode-cathode gap detection method of the battery cell, different features such as cathode features, anode features and gap features are distinguished by the grayscale value of the tomographic image of the battery cell to be tested and the physical properties of the electrode. The gap distance of the battery cell to be tested is calculated based on the pixel distance between the extracted cathode features and the anode features. The full-corner anode-cathode gap value of the entire battery cell can be detected, and the detection precision and accuracy are high, and the detection efficiency is high, which effectively ensures the safety of the battery cell.

[0047] like Figure 1As shown, the method for detecting the gap between the cathode and anode of a battery cell comprises: step 110, based on the image frames of the battery cell to be tested acquired at multiple different angles, obtaining a tomographic image corresponding to a target position in the battery cell to be tested; the image frame comprises image features of the electrode piece of the battery cell to be tested at a bend; step 120, based on the grayscale value of the tomographic image and the physical properties of the electrode, extracting at least one cathode feature and at least one anode feature; step 130, calculating the distance between adjacent cathode features and anode features to obtain a target gap distance.

[0048] In this embodiment, the battery cell to be tested includes a wound battery cell.

[0049] In some embodiments, the wound battery cells may include: cylindrical wound battery cells and square wound battery cells, etc.

[0050] The battery cell to be tested includes four bending areas, namely the areas corresponding to the bending of the electrode sheet, such as Figure 2 As shown, one bending area corresponds to one corner, and for each bending area, the corresponding image frame mode and processing flow are similar.

[0051] The image frame can be obtained by scanning the battery cell to be tested by X-Ray or CT ray. The image frame should include the image features of the pole piece of the battery cell to be tested at the bending point. Multiple different angles should cover the entire area involved in the same bending point of the battery cell to be tested, so that all the image features included in the multiple image frames should cover the image features in the entire bending area of ​​the battery cell to be tested as much as possible.

[0052] There are multiple image frames, and this application does not limit the number.

[0053] In some embodiments, the number of image frames should be no less than 180, such as set to 180, 300, 360 or other values.

[0054] The target position is a position corresponding to an area in the bending region of the battery cell to be tested that can reflect the characteristics of the anode and cathode, and the target position may be a preset position.

[0055] The tomographic image is an image representing the cross-section of the wound cell of the battery cell to be tested, such as Figure 4 shown.

[0056] The physical properties of the electrode are used to characterize the differences between the cathode and the anode, such as the size difference and arrangement characteristics of the anode and cathode.

[0057] In the tomographic image, the grayscale values ​​corresponding to the anode and cathode and the gap are different.

[0058] By extracting features based on the grayscale value, the area where the anode and cathode are located and the area where the gap is located can be distinguished.

[0059] After the regions where the anode and cathode electrodes are located are extracted, the cathode characteristics and the anode characteristics can be further distinguished based on the size differences of the regions to extract the cathode characteristics and the anode characteristics.

[0060] like Figure 5 As shown, the width of the region where the cathode is located is greater than the width of the region where the anode is located.

[0061] The cathode features and the anode features are generally arranged in alternating patterns.

[0062] The target gap distance is the distance between any adjacent cathode features and anode features.

[0063] In the actual implementation process, a plurality of alternately arranged cathode features and anode features may be extracted, and the distances between adjacent cathode features and anode features may be calculated respectively, thereby obtaining a plurality of target gap distances.

[0064] After the cathode features and anode features are extracted, the pixel distances between adjacent cathode features and anode features can be calculated according to the pixel coordinates of the cathode features and anode features in the tomographic image, such as Figure 5 As shown in the middle line segment, by converting the pixel distance into the actual distance, the target gap distance between adjacent cathode features and anode features can be obtained.

[0065] It should be noted that, taking a wound battery cell as an example, one or more target gap distances can be calculated between the same adjacent cathode features and anode features.

[0066] The target gap distances corresponding to different adjacent cathode features and anode features may be the same or different.

[0067] For each bending area of ​​the battery cell to be tested, the method of steps 110 to 130 can be used for testing, which will not be elaborated in this application.

[0068] In some embodiments, for a battery cell to be tested, the anode and cathode gap values ​​at at least two bending regions should be detected. For example, the anode and cathode gap values ​​corresponding to each bending region can be detected separately according to the method of steps 110 to 130; or the anode and cathode gap values ​​corresponding to the two diagonal bending regions can be detected; or the anode and cathode gap values ​​corresponding to the two bending regions located on the same side of the length direction of the battery cell to be tested can also be detected.

[0069] According to the method for detecting the gap between the cathode and anode of a battery cell provided in an embodiment of the present application, different features such as cathode features, anode features and gap features are distinguished by the grayscale value of the tomographic image of the battery cell to be tested and the physical properties of the electrode. The gap distance of the battery cell to be tested is calculated based on the pixel distance between the extracted cathode features and the anode features. The gap value of the cathode and anode pieces of the entire battery cell at all corners can be detected, and the detection precision and accuracy are relatively high, and the detection efficiency is relatively high, thereby effectively ensuring the safety of the battery cell.

[0070] In some embodiments, before step 110, the method may further include: controlling the field of view angle of the imaging system to be toward at least a portion of the electrode piece of the battery cell to be tested at the bend; controlling the imaging system to rotate based on a first angle, and controlling the imaging system to capture at least one image of the battery cell to be tested at each rotation angle to obtain image frames at multiple different angles.

[0071] In this embodiment, the first angle is a smaller angle and can be customized based on the user, such as being set to 0.5°, 1° or other values, etc., which is not limited in this application.

[0072] Continue to refer Figure 2 In the actual implementation process, the battery cell to be tested, such as the wound battery cell 250, can be placed in the tray 220 and then moved to the detection position by the robot arm. After the battery cell to be tested moves to the detection position, it remains stationary, and the detection area 230 (i.e., the bending area) is controlled to move to the center of the field of view of the imaging system. With the battery cell to be tested as the rotation center, the imaging system is controlled to collect multi-angle image frames based on the first angle rotation scanning.

[0073] In some embodiments, the imaging system may have a rotation angle range of no less than 180°.

[0074] For example, with the battery cell to be tested as the rotation center, the imaging system is controlled to perform a 0-180° rotation scan to collect image frames at multiple angles.

[0075] Taking the example of collecting one image frame at each rotation angle of 1° each time, at least 180 image frames can be collected for a bending area of ​​a battery cell to be tested.

[0076] According to the anode-cathode gap detection method of a battery cell provided in an embodiment of the present application, the imaging system is controlled to rotate and capture multiple image frames of the battery cell to be tested at the bending area, so as to capture image frames that can cover the image features corresponding to the entire bending area as much as possible, thereby improving the image capture accuracy, thereby improving the accuracy and precision of subsequent detection results.

[0077] In some embodiments, before step 110, the method may further include: controlling the field of view angle of the imaging system to be toward the two battery cells to be tested; wherein the two battery cells to be tested are placed diagonally, and at least a portion of the electrode pieces of each battery cell to be tested at the bend is located within the field of view angle; controlling the imaging system to collect image frames at multiple different angles, the image frames including image features of the electrode pieces of the two battery cells to be tested at the bend.

[0078] In this embodiment, two battery cells to be tested are placed diagonally, such as Figure 3 As shown, a bending area of ​​two battery cells to be tested is within the field of view of the imaging system. By controlling the imaging system to rotate and scan, image frames corresponding to the two bending areas can be collected simultaneously, thereby improving image collection efficiency.

[0079] According to the method for detecting the anode-cathode gap of a battery cell provided in an embodiment of the present application, by placing two battery cells to be tested diagonally, an imaging system collects image frames corresponding to the two battery cells to be tested at one time, thereby improving image acquisition efficiency and reducing detection costs.

[0080] In some embodiments, multiple battery cells to be tested may be stacked and placed, and image frames corresponding to the bending regions of the multiple stacked battery cells to be tested may be collected by an imaging system to improve image collection efficiency.

[0081] Continue to refer Figure 2 In some embodiments, the tray 220 at the bottom and the side ribs 210 of the battery cell to be tested may be made of a material with a low radiation absorption rate, such as carbon fiber, to improve the imaging effect.

[0082] The tray 220 and the bottom of the battery cell to be tested may be wrapped with foam to reduce the risk of damaging the battery cell to be tested during loading and unloading.

[0083] In some embodiments, step 110 may include: performing three-dimensional reconstruction on image frames of the battery cell to be tested acquired at multiple different angles to acquire a tomographic image.

[0084] In this embodiment, a filtered back-projection reconstruction algorithm may be used to perform three-dimensional reconstruction on multiple image frames to obtain a tomographic image.

[0085] According to the method for detecting the anode-cathode gap of a battery cell of the present application, by performing three-dimensional reconstruction on multiple image frames of the battery cell to be tested taken at multiple different angles, the three-dimensional information of the battery cell to be tested can be restored to retain more image features, thereby improving the precision and accuracy of the final tomographic image.

[0086] In some embodiments, three-dimensional reconstruction is performed on the image frames acquired at multiple different angles of the battery cell to be tested to obtain a tomographic image, which may include: three-dimensional reconstruction of the image frames acquired at multiple different angles to obtain a first image; feature extraction of the first image based on grayscale values ​​to locate the contour edge of the battery cell to be tested; and cutting processing is performed on the first image based on the contour edge to obtain a tomographic image corresponding to the target position.

[0087] In this embodiment, the contour edge is the cell edge of the battery cell to be tested.

[0088] It is understandable that the contour edge may be an irregular edge with some interfering features.

[0089] The first image is cut based on the contour edge to remove the interference features around the contour edge, so that the contour edge of the final tomographic image is a smooth edge, such as Figure 2 As shown in the cut-away view at position 240, the alignment of the cathode and anode is improved, and as many cathode and anode features as possible are displayed.

[0090] In the actual implementation process, a filtered back-projection reconstruction algorithm can be used to perform three-dimensional reconstruction on multiple image frames, restore the three-dimensional information of the battery cell to be tested, and obtain the first image.

[0091] After obtaining the first image, the contour edge of the battery cell to be tested is extracted by a contour extraction algorithm, and then the first image is cut according to the extracted contour edge to remove other interfering features, thereby realizing the detection of the alignment of the cathode and cathode as well as the detection of the alignment of the cathode and cathode at the end position of the wound battery cell.

[0092] According to the anode-cathode gap detection method of a battery cell provided in an embodiment of the present application, by performing image cutting processing on the reconstructed first image, the anode-cathode alignment can be improved, interference features around the contour edge can be removed, clearer anode-cathode features can be displayed, and imaging quality can be improved, thereby improving the precision and accuracy of subsequent anode-cathode gap detection.

[0093] In some embodiments, cutting the first image based on the contour edge to obtain a tomographic image corresponding to the target position may include: starting from the contour edge, moving the target distance toward the center of the battery cell to be tested to determine the first contour line; cutting the first image based on the first contour line to obtain a tomographic image.

[0094] In this embodiment, the target distance may be user-defined or determined based on historical test data.

[0095] For example, the target distance can be limited to between 3 and 4 mm.

[0096] The first contour line Figure 2The center cut view is shown at position 240.

[0097] After obtaining the first contour line, the first image is cut using the first contour line as a tangent line, and the image near the center of the battery cell is retained to obtain a tomographic image, such as Figure 4 As shown, in the tomographic image, the cathode and anode are aligned with each other, and relatively clear cathode and anode features can be displayed.

[0098] According to the anode-cathode gap detection method of a battery cell provided in an embodiment of the present application, by performing image cutting processing on the reconstructed first image, the anode-cathode alignment can be improved, interference features around the contour edge can be removed, clearer anode-cathode features can be displayed, and imaging quality can be improved, thereby improving the precision and accuracy of subsequent anode-cathode gap detection.

[0099] In some embodiments, step 120 may include: extracting multiple first feature regions and at least one second feature region based on grayscale values; obtaining the width of each first feature region; and classifying the first feature regions based on electrode physical properties and width to obtain cathode features and anode features.

[0100] In this embodiment, the first characteristic region is a region used to characterize cathode characteristics and anode characteristics.

[0101] The second characteristic region is a region used to characterize the gap characteristics between the cathode and anode.

[0102] There is a large difference in the grayscale values ​​corresponding to the first feature area and the second feature area, such as Figure 5 As shown, the lighter color area is the first characteristic area, and the darker color area is the second characteristic area.

[0103] The first feature region and the second feature region may be distinguished by setting a grayscale threshold; or the first feature region and the second feature region may be obtained by extracting features through an image recognition algorithm or a pre-trained network model.

[0104] After the first characteristic region is obtained, the first characteristic region can be further subdivided according to the physical characteristics of the anode and cathode electrodes.

[0105] The physical properties of the electrode are used to characterize the difference between the cathode and the anode, such as the size difference between the cathode and the anode (which can be reflected in the width difference of the first characteristic area) and the arrangement characteristics.

[0106] The width of the first characteristic region may be expressed as an average width, a minimum width or other values ​​of the first characteristic region, which is not limited in the present application.

[0107] Continue to refer Figure 5For multiple first characteristic regions, the wider region is the region corresponding to the cathode characteristics, and the narrower region is the region corresponding to the anode characteristics. The regions corresponding to the cathode characteristics and the regions corresponding to the anode characteristics are roughly arranged in an alternating pattern.

[0108] In some embodiments, the first characteristic regions are classified based on the physical properties and width of the electrode to obtain cathode characteristics and anode characteristics, which may include: determining the first characteristic regions whose width is greater than a first threshold as cathode characteristics, and determining the remaining first characteristic regions except the cathode characteristics among multiple first characteristic regions as anode characteristics.

[0109] In this embodiment, the first threshold value may be user-defined, or determined through test data, or may also be determined based on the type of the battery cell to be tested.

[0110] The first characteristic region whose width is greater than the first threshold value can be approximately regarded as the region where the cathode characteristic is located; and the remaining first characteristic region can be classified as the region where the anode characteristic is located.

[0111] Of course, in other embodiments, a second threshold may also be set, by determining the first characteristic region whose width is smaller than the second threshold as an anode characteristic, and determining the remaining first characteristic region as a cathode characteristic.

[0112] In other embodiments, the widths may be clustered by a clustering algorithm to distinguish cathode features from anode features, etc., which is not limited in the present application.

[0113] According to the anode-cathode gap detection method of a battery cell provided in an embodiment of the present application, the anode-cathode characteristics and the gap characteristics are distinguished by grayscale values ​​to extract a first characteristic area, and then the cathode characteristics and the anode characteristics are distinguished based on the thickness difference of the first characteristic area. The operation is simple and fast, the processing efficiency is high, and it has high extraction precision and accuracy, which helps to improve the accuracy of subsequent gap detection results.

[0114] In some embodiments, step 130 may include: emitting target rays in all directions with the midpoint of the battery cell to be tested as the center; extracting intersections between the target rays and the cathode features and the anode features; and determining the length between adjacent intersections as the target gap distance.

[0115] In this embodiment, the midpoint of the battery cell to be tested is as follows: Figure 4 As shown at point O.

[0116] The target ray is a ray that is emitted from point O as the midpoint toward the outermost cell of the battery to be tested, and the ray may be a virtual ray.

[0117] Continue to refer Figure 4, the target ray and the contour line corresponding to the cathode feature and the contour line corresponding to the anode feature presented on the tomographic image respectively generate intersection points, such as Figure 5 As shown, the line between two adjacent intersection points is the length between the two intersection points. By converting the pixel distance corresponding to the line into the physical distance, the target gap distance between the two intersection points can be obtained.

[0118] In some embodiments, emitting target rays around the midpoint of the battery cell to be tested may further include:

[0119] With the midpoint of the battery cell to be tested as the center and the target angle as the interval, multiple target rays are emitted in all directions.

[0120] In this embodiment, the target angle may be user-defined, and the target angle should not be greater than 360°; for example, the target angle may be set to 5°, 10°, or other values.

[0121] In the actual implementation process, multiple target rays can be emitted around the midpoint, and each target ray can generate an intersection with the cathode feature and the anode feature along the way. According to the calculation method described above, multiple lengths can be obtained, such as Figure 5 As shown in the middle line segment, the multiple lengths obtained are converted into physical distances respectively, and the obtained physical distances are determined as gap distances, which are output as the final target gap distances. Thus, the gap distances at multiple different positions of the wound battery cell under each winding layer can be obtained, which has high granularity and comprehensiveness.

[0122] According to the method for detecting the gap between the cathode and anode of a battery cell provided in an embodiment of the present application, a target ray is emitted in all directions with the midpoint of the battery cell to be tested as the center, and the gap between each adjacent cathode and anode is calculated based on the length between the intersection of the target ray and the cathode feature and the anode feature. This method has a high calculation granularity and is capable of detecting the gap value between the cathode and anode pieces at all corners of the entire battery cell, further improving the accuracy and authenticity of the calculation results.

[0123] The cathode gap detection method of a battery cell provided in the embodiment of the present application can be performed by an cathode gap detection device of a battery cell. The cathode gap detection method of a battery cell is performed by an cathode gap detection device of a battery cell as an example to illustrate the cathode gap detection device of a battery cell provided in the embodiment of the present application.

[0124] The embodiment of the present application also provides a device for detecting the gap between anode and cathode of a battery cell.

[0125] like Figure 7As shown, the cathode and anode gap detection device of the battery cell includes: a first processing module 710, which is used to obtain a tomographic image corresponding to a target position in the battery cell to be tested based on image frames of the battery cell to be tested at multiple different angles; the image frame includes image features of the electrode piece of the battery cell to be tested at a bend; a second processing module 720, which is used to extract at least one cathode feature and at least one anode feature based on the grayscale value of the tomographic image and the physical properties of the electrode; and a third processing module 730, which is used to calculate the distance between adjacent cathode features and anode features to obtain a target gap distance.

[0126] According to the anode-cathode gap detection device for a battery cell provided in an embodiment of the present application, different features such as cathode features, anode features and gap features are distinguished by the grayscale value of the tomographic image of the battery cell to be tested and the physical properties of the electrode, and the gap distance of the battery cell to be tested is calculated based on the pixel distance between the extracted cathode features and the anode features. The gap value of the anode-cathode pieces at all corners of the entire battery cell can be detected, and the detection precision and accuracy are high, and the detection efficiency is high, which effectively ensures the safety of the battery cell.

[0127] In some embodiments, the second processing module 720 can also be used to: extract multiple first feature regions and at least one second feature region based on grayscale values; obtain the width of each first feature region; classify the first feature regions based on the electrode physical properties and width to obtain cathode features and anode features.

[0128] In some embodiments, the third processing module 730 can also be used to: emit target rays around the midpoint of the battery cell to be tested; extract the intersection points between the target rays and the cathode features and the anode features; and determine the length between adjacent intersection points as the target gap distance.

[0129] In some embodiments, the first processing module 710 may also be used to: perform three-dimensional reconstruction on the image frames of the battery cell to be tested acquired at multiple different angles to acquire a tomographic image.

[0130] In some embodiments, the first processing module 710 can also be used to: perform three-dimensional reconstruction of image frames at multiple different angles to obtain a first image; perform feature extraction on the first image based on grayscale values ​​to locate the contour edge of the battery cell to be tested; and perform image cutting processing on the first image based on the contour edge to obtain a tomographic image corresponding to the target position.

[0131] In some embodiments, the first processing module 710 can also be used to: start from the contour edge, move a target distance toward the center of the battery cell to be tested, and determine a first contour line; perform image cutting processing on the first image based on the first contour line to obtain a tomographic image.

[0132] In some embodiments, the device may also include a fourth processing module, which is used to: before obtaining a tomographic image corresponding to a target position in the battery cell to be tested based on the acquired image frames of the battery cell to be tested at multiple different angles, control the field of view angle of the imaging system to be directed toward at least a partial area of ​​the pole piece of the battery cell to be tested at the bend; control the imaging system to rotate based on the first angle, and control the imaging system to capture at least one image of the battery cell to be tested at each rotation angle to obtain image frames at multiple different angles.

[0133] In some embodiments, the device may also include a fifth processing module, which is used to: before obtaining the tomographic image corresponding to the target position in the battery cell to be tested based on the acquired image frames of the battery cell to be tested at multiple different angles, control the field of view angle of the imaging system to be directed toward the two battery cells to be tested; wherein the two battery cells to be tested are placed diagonally, and at least a portion of the pole pieces of each battery cell to be tested at the bend is located within the field of view angle; control the imaging system to collect image frames at multiple different angles, and the image frames include image features of the pole pieces of the two battery cells to be tested at the bend.

[0134] The battery cell cathode and anode gap detection device provided in the embodiment of the present application can achieve Figures 1 to 6 To avoid repetition, the various processes implemented by the method embodiment are not described here.

[0135] The embodiment of the present application also provides a method for detecting a battery cell.

[0136] like Fig. 9 As shown, the battery cell detection method includes: step 910, determining the target gap distance of the battery cell to be tested based on the anode-cathode gap detection method of the battery cell as described in any of the above embodiments; step 920, determining that the battery cell to be tested is unqualified when the target gap distance is greater than the safety distance threshold.

[0137] In this embodiment, the safety distance threshold may be determined based on the type and specification of the battery cell to be tested.

[0138] When the target gap distance is not greater than the safety distance threshold, it can be approximately considered that the target gap distance is qualified.

[0139] When the target gap distance is greater than the safety distance threshold, it can be approximately considered that the target gap distance is unqualified.

[0140] In some embodiments, multiple target gap distances obtained by the anode-cathode gap detection method based on battery cells can be compared with the safety threshold distances respectively. If one or more target gap distances are greater than the safety distance threshold, the battery cell to be tested is determined to be unqualified, such as being marked as an NG battery cell.

[0141] In the case that there is no target gap distance greater than the safety distance threshold, or there is a small number (negligible) of target gap distances greater than the safety distance threshold, the battery cell to be tested can be judged to be qualified, such as marking it as an OK battery cell. Figure 6 shown.

[0142] According to the battery cell detection method provided in the embodiment of the present application, different features such as cathode features, anode features and gap features are distinguished by the grayscale value of the tomographic image, the gap distance between the anode and cathode of the battery cell to be tested is calculated based on the extracted cathode features and anode features, and safety detection is performed based on the gap distance and product specifications. The method has high detection accuracy and detection efficiency, and effectively ensures the safety of the battery cell.

[0143] The battery cell detection method provided in the embodiment of the present application can be executed by a battery cell detection device. In the embodiment of the present application, the battery cell detection device provided in the embodiment of the present application is described by taking the battery cell detection method performed by the battery cell detection device as an example.

[0144] The embodiment of the present application also provides a battery cell detection device.

[0145] like Fig.10 As shown, the cathode and anode gap detection device of the battery cell includes: a sixth processing module 1010, which is used to determine the target gap distance of the battery cell to be tested based on the cathode and anode gap detection method of the battery cell described in any of the above embodiments; a seventh processing module 1020, which is used to determine that the battery cell to be tested is unqualified when the target gap distance is greater than a safety distance threshold.

[0146] According to the battery cell detection device provided in the embodiment of the present application, different features such as cathode features, anode features and gap features are distinguished by the grayscale value of the tomographic image, the gap distance between the positive and negative electrodes of the battery cell to be tested is calculated based on the extracted cathode features and anode features, and safety detection is performed based on the gap distance and product specifications. It has high detection accuracy and detection efficiency, and effectively ensures the safety of the battery cell.

[0147] The cathode and anode gap detection device of the battery cell or the detection device of the battery cell in the embodiment of the present application can be an electronic device or a component in the electronic device, such as an integrated circuit or a chip. The electronic device can be a terminal or other devices other than a terminal. Exemplarily, the electronic device can be a mobile phone, a tablet computer, a laptop computer, a PDA, a vehicle-mounted electronic device, a mobile Internet device (Mobile Internet Device, MID), an augmented reality (augmented reality, AR) / virtual reality (virtual reality, VR) device, a robot, a wearable device, an ultra-mobile personal computer (ultra-mobile personal computer, UMPC), a netbook or a personal digital assistant (personal digital assistant, PDA), etc. It can also be a server, a network attached storage (Network Attached Storage, NAS), a personal computer (personal computer, PC), a television (television, TV), a teller machine or a self-service machine, etc., which is not specifically limited in the embodiment of the present application.

[0148] The battery cell cathode and anode gap detection device or battery cell detection device in the embodiment of the present application may be a device with an operating system. The operating system may be an Android operating system, an IOS operating system, or other possible operating systems, which are not specifically limited in the embodiment of the present application.

[0149] The battery cell detection device provided in the embodiment of the present application can achieve Fig. 9 To avoid repetition, the various processes implemented by the method embodiment are not described here.

[0150] The embodiment of the present application also provides a detection system.

[0151] The detection system includes: an imaging system and a processing module.

[0152] The field of view of the imaging system is oriented toward the target angle of the battery cell to be tested, and is used to collect image frames of the target angle at multiple different angles.

[0153] The imaging system includes: a microfocus X-ray source and a flat-panel detector.

[0154] The flat panel detector is electrically connected to the micro-focus X-ray source.

[0155] A microfocus X-ray source is a device that emits X-rays at a specific emission angle from an X-ray focal point.

[0156] The microfocus X-ray source is used to emit CT rays or X-ray rays, etc.

[0157] The smaller the focal spot size of a microfocus X-ray source, the higher the image resolution.

[0158] In some embodiments, the microfocus X-ray source has a focal spot size of <50 um.

[0159] By setting a micro-focus X-ray source with a focus size of less than 50um, the gap between the cathode and anode pieces in the range of 30um to 200um can be clearly observed, effectively improving the imaging quality and thus improving the detection precision and accuracy.

[0160] The flat-panel detector is used to convert the rays emitted by the micro-focus X-ray source into electrical signals. By measuring the amount of X-rays it receives, it produces a picture of the signal proportional to the X-rays, thereby generating an image frame of the battery cell to be tested.

[0161] It should be noted that, for the same target angle, the more image frames are collected, the better the imaging effect of the tomographic image finally obtained by three-dimensional reconstruction.

[0162] The frame rate of the flat panel detector may be determined based on the imaging accuracy or the number of acquired image frames.

[0163] Taking the acquisition of more than 300 image frames within 6 seconds as an example, a high frame rate flat panel detector of more than 50 frames can be selected, that is, 50 image frames can be acquired within 1 second, thereby ensuring the imaging effect of the tomographic image.

[0164] The processing module is electrically connected to the imaging system, and is used to receive image frames captured by the imaging system and execute the method for detecting the cathode and anode gap of a battery cell as described in any of the above embodiments.

[0165] In some embodiments, the detection system may further include: a base.

[0166] In this embodiment, the base is used to place the battery cell to be tested.

[0167] In some embodiments, the base may include a rib 210 , a tray 220 , and a rotating ring.

[0168] The ribs 210 and the tray 220 are used to place the battery cells to be tested, and the ribs 210 and the tray 220 can be fixed.

[0169] like Figure 2 As shown, in some embodiments, the rib 210 and the tray 220 may be made of a material with a low radiation absorption rate, such as carbon fiber, to improve the imaging effect.

[0170] In some embodiments, the tray 220 may be wrapped with foam to reduce the risk of damaging the battery cells to be tested during loading and unloading.

[0171] A micro-focus X-ray source and a flat-panel detector are mounted on the rotating ring, and the rotating ring can rotate within a range of 360° to drive the micro-focus X-ray source and the flat-panel detector to rotate.

[0172] In some embodiments, a servo motor and a belt drive with a high reduction ratio may be provided to ensure the accuracy of motion control.

[0173] Continue to refer Figure 6 In the actual implementation process, the battery cell to be tested can be placed on the tray 220 to complete the loading; then the target angle is scanned and imaged by the micro-focus X-ray source and the flat-panel detector to obtain multiple image frames; the processing module performs three-dimensional reconstruction on the multiple image frames to obtain a tomographic image, and performs anode and cathode gap detection on the tomographic image to obtain a target gap distance; then the battery cell to be tested is tested for good and defective products based on the target gap distance.

[0174] According to the detection system provided in the embodiment of the present application, a micro-focus X-ray source is set to collect multiple image frames of the target angle of the battery cell to be tested at multiple different angles, so as to distinguish different features such as cathode features, anode features and gap features based on the grayscale value of the tomographic image obtained from the multiple image frames and the physical properties of the electrode, and calculate the gap distance of the battery cell to be tested based on the pixel distance between the extracted cathode features and the anode features. The gap value of the anode and cathode pieces at all corners of the entire battery cell can be detected, and the detection precision and accuracy are high, and the detection efficiency is high, which effectively ensures the safety of the battery cell.

[0175] The embodiment of the present application also provides a battery cell.

[0176] The battery cells mentioned in the embodiments of the present application may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries or magnesium-ion batteries, etc., which are not limited in the embodiments of the present application. The battery cells may be cylindrical, flat, rectangular or other shapes, etc., which are not limited in the embodiments of the present application. Battery cells are generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells and soft-pack battery cells, which are not limited in the embodiments of the present application.

[0177] The battery cell includes a shell, an electrode assembly and an electrolyte, and the shell is used to contain the electrode assembly and the electrolyte. The electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode collector. The positive electrode collector not coated with the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer. The positive electrode collector not coated with the positive electrode active material layer serves as a positive electrode ear. Taking lithium-ion batteries as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer. The negative electrode current collector not coated with the negative electrode active material layer serves as a negative electrode tab. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon, etc. In order to ensure that a large current passes without melting, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together.

[0178] The material of the isolation film may be PP (polypropylene) or PE (polyethylene), etc. In addition, the electrode assembly may be a winding structure or a stacked structure, but the embodiments of the present application are not limited thereto.

[0179] In some embodiments, when the battery cell is of a wound structure, the wound battery cell may include: a cylindrical wound battery cell and a square wound battery cell, etc.

[0180] The battery cell may be detected based on the anode-cathode gap detection method of the battery cell as described in any of the above embodiments.

[0181] According to the battery cell provided in the embodiment of the present application, different features such as cathode features, anode features and gap features are distinguished by processing the grayscale values ​​of the tomographic images obtained after processing multiple frames of images of the electrode of the battery cell to be tested at multiple different angles at the bend, as well as the physical properties of the electrode. Based on the pixel distance between the extracted cathode features and the anode features, the gap distance of the battery cell to be tested is calculated, and the gap value of the anode and cathode pieces at all corners of the entire battery cell can be detected. The detection precision and accuracy are high, and the detection efficiency is high, which effectively ensures the safety of the battery cell.

[0182] The embodiment of the present application also provides an electrical device.

[0183] The electrical equipment may include a battery cell or an energy storage device as described in any of the above embodiments.

[0184] The energy storage device includes one or more battery clusters to increase the voltage and capacity of the energy storage device. The battery cluster may include multiple battery cells, which are connected in series through a busbar to increase the voltage of the energy storage device. When the energy storage device includes multiple battery clusters, the multiple battery clusters are connected in parallel to increase the capacity of the energy storage device.

[0185] The energy storage device can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems or temporary power supply systems. The energy storage device can store electrical energy as needed and output electrical energy at an appropriate time. For example, the energy storage device can store electrical energy during low power consumption and provide electrical energy to relevant users or electrical equipment during peak power consumption. The energy storage system provided in the embodiment of the present application can be any power system that requires the use of an energy storage device.

[0186] In some embodiments, the energy storage device is an energy storage container or an energy storage cabinet.

[0187] In some embodiments, the energy storage device may include a cabinet and one or more battery clusters, wherein the battery clusters are housed in the cabinet.

[0188] In some embodiments, the energy storage device may include modules such as a thermal management module, a main control module, a master control module, a power distribution module, and a fire protection module.

[0189] In some embodiments, the power-consuming equipment may include, but is not limited to: non-mobile power-consuming equipment, mobile power-consuming equipment, or temporary power-consuming equipment.

[0190] For example, mobile power-consuming devices may include, but are not limited to: mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, hybrid vehicles, electric ships, spacecraft, and other power-consuming devices, etc. Among them, electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft may include airplanes, rockets, space shuttles, and spacecrafts, etc.

[0191] According to the electrical equipment provided in the embodiment of the present application, different features such as cathode features, anode features and gap features are distinguished by processing the grayscale values ​​of the tomographic images obtained after processing multiple frames of images of the electrode of the battery cell to be tested at multiple different angles at the bend, as well as the physical properties of the electrode, and the pixel distance between the extracted cathode features and the anode features is used to calculate the gap distance of the battery cell to be tested. The gap value of the anode and cathode plates at all corners of the battery cell can be detected, and the detection precision and accuracy are relatively high, and the detection efficiency is relatively high, so the safety of the battery cell is effectively guaranteed, thereby improving the safety of the use of the electrical equipment.

[0192] In some embodiments, Figure 8 As shown, an embodiment of the present application further provides an electronic device 800, including a processor 801, a memory 802, and a computer program stored in the memory 802 and executable on the processor 801. When the program is executed by the processor 801, each process of the above-mentioned battery cell anode-cathode gap detection method or the battery cell detection method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be described here.

[0193] It should be noted that the electronic devices in the embodiments of the present application include the mobile electronic devices and non-mobile electronic devices mentioned above.

[0194] An embodiment of the present application also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the various processes of the above-mentioned battery cell anode-cathode gap detection method or battery cell detection method embodiment are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0195] The processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

[0196] An embodiment of the present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the above-mentioned battery cell cathode and anode gap detection method or battery cell detection method.

[0197] The processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

[0198] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of the above-mentioned embodiment of the anode-cathode gap detection method of the battery cell, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0199] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0200] It should be noted that, in this article, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises one..." does not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be noted that the scope of the method and device in the embodiment of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0201] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0202] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0203] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0204] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for detecting the gap between cathode and anode of a battery cell, characterized in that: include: Based on the acquired image frames of the battery cell to be tested at multiple different angles, a tomographic image corresponding to a target position in the battery cell to be tested is acquired; the image frame includes image features of the pole piece of the battery cell to be tested at a bend; Extracting at least one cathode feature and at least one anode feature based on the grayscale value of the tomographic image and the physical properties of the electrode; Calculating the distance between the adjacent cathode features and the adjacent anode features to obtain a target gap distance; Before acquiring a tomographic image corresponding to a target position in the battery cell to be tested based on the acquired image frames of the battery cell to be tested at multiple different angles, the method includes: Controlling the field of view of the imaging system to be oriented toward at least a portion of the electrode piece of the battery cell to be tested at the bend; Controlling the imaging system to rotate based on a first angle, and controlling the imaging system to capture at least one image of the battery cell to be tested at each rotation angle, to obtain the image frames at the multiple different angles; The rotation angle range of the imaging system is not less than 180°; The extracting at least one cathode feature and at least one anode feature based on the grayscale value of the tomographic image and the physical characteristics of the electrode comprises: Based on the grayscale value, extracting a plurality of first feature regions and at least one second feature region; Obtaining the width of each of the first characteristic regions; Based on the electrode physical characteristics and the width, the first characteristic region is classified to obtain the cathode characteristic and the anode characteristic; The first characteristic regions are classified based on the electrode physical characteristics and the width to obtain the cathode characteristics and the anode characteristics, including: determining the first characteristic regions whose width is greater than a first threshold as the cathode characteristics, and determining the remaining first characteristic regions among the plurality of the first characteristic regions except the cathode characteristics as the anode characteristics.

2. The method for detecting the gap between the cathode and anode of a battery cell according to claim 1, characterized in that: The calculating the distance between the adjacent cathode features and the adjacent anode features to obtain a target gap distance comprises: emitting target rays in all directions with the midpoint of the battery cell to be tested as the center; extracting intersection points between the target ray and the cathode feature and the anode feature; The length between adjacent intersection points is determined as the target gap distance.

3. The method for detecting the gap between cathode and anode of a battery cell according to claim 1 or 2, characterized in that: The method of acquiring a tomographic image corresponding to a target position in the battery cell to be tested based on the acquired image frames of the battery cell to be tested at multiple different angles includes: The image frames of the battery cell to be tested acquired at multiple different angles are three-dimensionally reconstructed to acquire the tomographic image.

4. The method for detecting the gap between cathode and anode of a battery cell according to claim 3, characterized in that: The three-dimensional reconstruction of the image frames of the battery cell to be tested acquired at multiple different angles to acquire the tomographic image comprises: Performing three-dimensional reconstruction on the image frames at the multiple different angles to obtain a first image; Performing feature extraction on the first image based on grayscale values ​​to locate the contour edge of the battery cell to be tested; The first image is cut based on the contour edge to obtain a tomographic image corresponding to the target position.

5. The method for detecting the gap between cathode and anode of a battery cell according to claim 4, characterized in that: The performing image cutting processing on the first image based on the contour edge to obtain a tomographic image corresponding to the target position includes: Taking the edge of the contour as a starting point, moving a target distance toward the center of the battery cell to be tested to determine a first contour line; The first image is cut based on the first contour line to obtain the tomographic image.

6. The method for detecting the gap between cathode and anode of a battery cell according to claim 1 or 2, characterized in that: Before acquiring a tomographic image corresponding to a target position in the battery cell to be tested based on the acquired image frames of the battery cell to be tested at multiple different angles, the method includes: Controlling the field of view of the imaging system to be oriented toward the two battery cells to be tested; wherein the two battery cells to be tested are placed diagonally, and at least a portion of the electrode piece of each battery cell to be tested at the bend is located within the field of view; The imaging system is controlled to collect the image frames at multiple different angles, wherein the image frames include image features of the pole pieces of the two battery cells to be tested at the bending locations.

7. A method for detecting a battery cell, characterized in that: include: Determine the target gap distance of the battery cell to be tested based on the anode-cathode gap detection method of the battery cell according to any one of claims 1 to 6; When the target gap distance is greater than the safety distance threshold, it is determined that the battery cell to be tested is unqualified.

8. A battery cell cathode and anode gap detection device, characterized in that: include: A first processing module is used to obtain a tomographic image corresponding to a target position in the battery cell to be tested based on image frames of the battery cell to be tested obtained at multiple different angles; the image frame includes image features of the electrode piece of the battery cell to be tested at a bend; A second processing module, configured to extract at least one cathode feature and at least one anode feature based on the grayscale value of the tomographic image and the physical properties of the electrode; A third processing module is used to calculate the distance between the adjacent cathode features and the adjacent anode features to obtain a target gap distance; The second processing module is used to: Based on the grayscale value, extracting a plurality of first feature regions and at least one second feature region; Obtaining the width of each of the first characteristic regions; Based on the electrode physical characteristics and the width, the first characteristic region is classified to obtain the cathode characteristic and the anode characteristic; The second processing module is used to: determine a first feature region whose width is greater than a first threshold as the cathode feature, and determine the remaining first feature regions among the plurality of first feature regions except the cathode feature as the anode feature.

9. A detection system, characterized in that: include: An imaging system, wherein the field of view of the imaging system is oriented toward a target angle of the battery cell to be tested, the imaging system comprising a micro-focus X-ray source and a flat-panel detector electrically connected to the micro-focus X-ray source, the flat-panel detector being used to convert the X-rays emitted by the micro-focus X-ray source into electrical signals and generate image frames of the battery cell to be tested at multiple different angles; A processing module, the processing module is electrically connected to the imaging system, and is used to execute the anode-cathode gap detection method of a battery cell as described in any one of claims 1 to 6 or the battery cell detection method as described in claim 7.

10. A battery cell, characterized in that: The battery cell determines the cathode and anode gap based on the cathode and anode gap detection method of the battery cell according to any one of claims 1 to 6, or performs detection based on the battery cell detection method according to claim 7.

11. An electrical device, characterized in that: The electric device comprises the battery cell as claimed in claim 10.

12. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for detecting the gap between the cathode and anode of a battery cell as described in any one of claims 1 to 6 or the method for detecting the gap between the cathode and anode of a battery cell as described in claim 7 is implemented.

13. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for detecting the cathode and anode gap of a battery cell according to any one of claims 1 to 6 or the method for detecting a battery cell according to claim 7 is implemented.

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