Battery cell surface foreign matter detection device

Abstract

The utility model relates to battery technical field discloses a kind of battery cell surface foreign matter detection devices, including photographing mechanism and battery cell bearing component, and photographing mechanism includes light source assembly and camera.Battery cell bearing component is used to place battery cell to be measured.Light source assembly is set to one side of battery cell bearing component, and light source assembly includes lampshade and multiple light sources, and multiple light sources are spaced apart to set in the inner wall of lampshade around the axis of lampshade, each light source is parallelly connected, and when light source is lighted, light emitted by light source forms dome light.Camera is set to one side of light source assembly, which is away from battery cell bearing component, and the side of lampshade, which is towards camera, has through-hole coaxially arranged with lampshade, and camera is used to shoot 2.5D image of the surface of battery cell to be measured through through-hole when multiple light sources are respectively lighted.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a foreign object detection device for battery cell surface. Background Technology

[0002] Before being installed into the battery casing, the battery cell needs to go through multiple processes. During each process, foreign objects such as metal can easily enter the film layer structure covering the surface of the battery cell. After the battery cell is installed in the casing, the metal foreign objects can easily puncture the Mylar film and separator covering the surface of the battery cell, causing a short circuit and affecting the safety performance of the battery.

[0003] Currently, to prevent battery cells with metallic foreign objects from entering the production line, inspection mechanisms are usually installed to detect whether there are foreign objects on the surface of the battery cells. However, existing inspection technologies are not accurate enough to detect all defective battery cells. Utility Model Content

[0004] To address the problem of insufficient detection accuracy in existing battery cell technologies, this invention provides a foreign object detection device for battery cell surfaces, which can improve the detection accuracy of foreign objects on the battery cell surface.

[0005] To achieve the above objectives, this utility model provides a foreign object detection device for battery cell surface, including a battery cell support component and a photographing mechanism, wherein the photographing mechanism includes a light source assembly and a camera; The cell-supporting component is used to place the cell to be tested; The light source assembly is disposed on one side of the battery cell support component. The light source assembly includes a lampshade and multiple light sources. The multiple light sources are spaced apart on the inner wall of the lampshade around the axis of the lampshade. The light sources are connected in parallel, and when the light source is lit, the light emitted by the light source forms a dome light. The camera is positioned on the side of the light source assembly away from the battery cell support component. The lampshade has a through hole coaxially arranged on the side facing the camera. The camera is used to capture a 2.5D image of the surface of the battery cell under test through the through hole when each of the light sources is lit.

[0006] The foreign object detection device for battery cells described above has the following advantages: When using the device to inspect the battery cell under test, each light source can be lit individually and sequentially. When each light source is lit, a camera captures a 2.5D image of the battery cell surface under that light source condition. Finally, the multiple images are fused to determine whether there are any metallic foreign objects on the battery cell surface. Because the light sources are located inside the lampshade, the light emitted by the light sources can form a uniform and soft dome light after multiple diffuse reflections through the inner wall, providing excellent shooting conditions for the camera. The sequential individual lighting of the light sources can capture a series of brightness and darkness changes of the battery cell under test at different illumination angles. Simultaneously, by capturing 2.5D images of the battery cell surface, the height changes on the surface of the battery cell can be effectively and accurately reflected, making it easier to identify whether there are any metallic foreign objects on the surface of the battery cell under test. Thus, the detection device described above can improve the accuracy of the inspection, thereby contributing to increased production efficiency. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of a foreign object detection device on the surface of a battery cell in an embodiment of this utility model; Figure 2 This is a schematic diagram of the photographing mechanism in one embodiment of the present utility model; Figure 3 This is a bottom view of the light source assembly in an embodiment of the present utility model; Figure 4 This is a side view of the photographing mechanism and the battery cell under test in an embodiment of this utility model; Figure 5 This is a schematic diagram of the foreign object detection device on the surface of the battery cell from another perspective in an embodiment of this utility model; Figure 6 This is a schematic diagram of a battery cell support component in an embodiment of the present invention; Figure 7 This is another structural schematic diagram of the foreign matter detection device on the surface of the battery cell in this embodiment of the present invention; Figure 8 This is another structural schematic diagram of the foreign matter detection device on the surface of the battery cell in this embodiment of the present invention; Figure 9 This is another side view of the photographing mechanism and the battery cell under test in this embodiment of the present utility model; Figure 10 This is a schematic diagram of another structure of the battery cell support component in this utility model embodiment.

[0008] In the picture: 10-Battery cell under test; 100-Battery cell carrier component; 101-Carrier plate; 102-Clamping plate; 1021-Slot; 103-Second guide rail; 104-L-shaped connecting plate; 105-First roller; 106-Second roller; 107-Drive component; 108-Transmission component; 1081-Driving gear; 1082-Driven gear; 1083-Synchronous belt; 109-Limiting plate; 200-Photography mechanism; 210-Light source assembly; 211-Lamp cover; 2111-Through hole; 212-Light source; 220-Camera; 230-Light shield; 300-Working platform; 400-First guide rail. Detailed Implementation

[0009] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0010] refer to Figure 1 The foreign object detection device on the surface of the battery cell in this embodiment may include a battery cell support component 100 and an imaging mechanism 200. The battery cell support component 100 is used to place the battery cell 10 to be tested, and the imaging mechanism 200 is used to take an image of the battery cell 10 to be tested.

[0011] For details, please refer to the following: Figures 1 to 3 The imaging mechanism 200 may include a light source assembly 210 and a camera 220. The light source assembly 210 is disposed on one side of the battery cell support component 100. The light source assembly 210 includes a lampshade 211 and a plurality of light sources 212. The lampshade 211 has an internal receiving space, and the plurality of light sources 212 are disposed within the receiving space and respectively fixed to the inner wall of the lampshade 211. The plurality of light sources 212 are spaced apart around the axis of the lampshade 211. When the light sources 212 are lit, the light emitted by the light sources 212 can form a dome light that illuminates the surface of the battery cell 10 under test.

[0012] Multiple light sources 212 are connected in parallel, meaning that the switching of each light source 212 does not affect each other, and each light source 212 can be lit or turned off independently.

[0013] Camera 220 is positioned on the side of light source assembly 210 facing away from cell support component 100. Lamp cover 211 has a through hole 2111 on the side facing camera 220, the axis of the through hole 2111 coinciding with the axis of lamp cover 211; that is, the through hole 2111 and lamp cover 211 are coaxially arranged. Camera 220 can be used to capture a 2.5D image of the surface of the cell 10 under test through the through hole 2111 when each light source 212 is lit.

[0014] It should be noted that, in this embodiment, when the battery cell 10 under test is being tested, the foreign object detection device first places the battery cell 10 on the battery cell support component 100, then individually illuminates each light source 212. When each light source 212 is illuminated, a camera 220 captures a 2.5D image of the surface of the battery cell 10 under that light source 212 condition. That is, the number of images captured by the camera 220 is the same as the number of light sources 212. Finally, the multiple images are fused to determine whether there are any metallic foreign objects on the surface of the battery cell. Since the light sources 212 are located inside the lampshade 211, the light emitted by the light sources 212 can form a uniform and soft dome light after multiple diffuse reflections through the inner wall, providing good shooting conditions for the camera 220. The sequential individual illumination of the light sources 212 can capture a series of brightness and darkness changes of the battery cell 10 under different lighting angles. Simultaneously, by capturing 2.5D images of the surface of the battery cell 10, the 2.5D images can effectively and accurately reflect the height changes on the surface of the battery cell 10. When there are impurities such as dust on the surface of the battery cell 10, the dust impurities do not have a significant height difference on the surface of the battery cell 10, while the metal foreign objects will show a significant height difference on the surface of the battery cell 10. Therefore, by taking 2.5D images, it is easier to identify whether there are metal foreign objects on the surface of the battery cell 10 under test, thereby improving the accuracy of detection and helping to improve production efficiency.

[0015] Specifically, in designing the light source assembly 210, the lampshade 211 can be a hemispherical structure or an arched structure with an angle of 120° or greater. Furthermore, the inner wall of the lampshade 211 has a highly reflective and diffuse coating to ensure that light can be reflected multiple times within the lampshade 211 without significant attenuation. When the light source 212 is lit, the light first strikes the inner wall of the lampshade 211, undergoes at least one diffuse reflection, and then illuminates the battery cell 10 under test. This forms a dome light with uniform heat dissipation. The dome light eliminates shadows and glare, thus providing better lighting conditions when the camera 220 is shooting, effectively suppressing reflections on the surface of the battery cell 10, enhancing the surface texture of the battery cell 10, and making it easier to determine whether there are metallic foreign objects on the surface of the battery cell 10.

[0016] In some embodiments, such as Figure 1 As shown, the cell-carrying component 100 can be used to place square cells, meaning that the detection device in this embodiment can be used to detect square cells. At this time, the camera 220 can be used to capture a 2.5D image of a large surface of the cell 10 under test.

[0017] Specifically, in this embodiment, reference is made to... Figure 4The distance d1 mm between the lampshade 211 and the large surface of the battery cell 10 under test is 10mm~70mm to maintain a certain gap between them. This gap ensures the uniformity of the diffused light field, eliminating direct light and glare, while also satisfying the focusing and field-of-view coverage of the camera 220, and preventing shadows from interfering with the identification of foreign objects on the surface of the battery cell 10 under test. In addition, maintaining a certain gap between the lampshade 211 and the battery cell 10 under test also facilitates the placement and removal of the battery cell 10 under test, and prevents the battery cell 10 from being damaged by heat due to being too close to the light source 212.

[0018] In practical applications, d1 mm can be 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, etc. The specific d1 mm can be adaptively designed according to factors such as the camera 220 parameters and the model of the battery cell under test.

[0019] In one optional embodiment, the light source 212 can be an infrared light source with a wavelength between 760nm and 1700nm. For example, the wavelength of the infrared light source can be 760nm, 800nm, 840nm, 900nm, 940nm, 1000nm, 1100nm, 1200nm, 1300nm, etc. Infrared light has strong penetrating power and can penetrate the film layer on the surface of the battery cell 10 under test to capture the metal impurities beneath the film layer, thereby further improving the detection accuracy. Preferably, the light source 212 can be an infrared light source with a wavelength of approximately 940nm.

[0020] Correspondingly, camera 220 can be a 25MP monochrome global area array camera, meaning camera 220 can be a monochrome industrial camera with approximately 25 million pixels, employing global shutter technology and a 2D area array sensor, capable of capturing a complete 2D image in a single shot and retaining depth information. Correspondingly, the lens of camera 220 can be a 16mm focal length lens.

[0021] At this time, the distance d2 mm between the camera 220 and the large surface of the battery cell 10 under test can be 340mm~400mm to meet the focusing and field of view coverage of the camera 220 and avoid shadows interfering with the identification of foreign objects on the surface of the battery cell 10 under test. Specifically, d2 mm can be 340mm, 345mm, 350mm, 355mm, 360mm, 365mm, 370mm, 375mm, 380mm, 385mm, 390mm, 395mm, 400mm, etc.

[0022] The distance d3 mm between the light source 212 and the large surface of the battery cell 10 under test can be 140mm~200mm, so that a certain distance is maintained between the light source 212 and the bottom of the lamp cover 211. The light emitted by the light source 212 can be diffusely reflected multiple times by the inner wall of the lamp cover 211, thereby ensuring the uniformity of light and improving the quality of the captured image. Specifically, d3 mm can be 140mm, 145mm, 150mm, 155mm, 160mm, 165mm, 170mm, 175mm, 180mm, 185mm, 190mm, 195mm, 200mm, etc.

[0023] Further reference Figure 4 In this embodiment, the field of view of the camera 220 is D1 mm. D1mm, where D1 mm is 180mm~200mm. It's understandable that if the field of view of camera 220 is too large, the pixel density of the image captured by camera 220 decreases, leading to reduced image quality and affecting subsequent image processing for identifying foreign objects on the surface of the battery cell 10 under test. Conversely, if the field of view of camera 220 is too small, given the fixed surface area of ​​the battery cell 10 under test, multiple movements of the battery cell 10 or camera 220 are required, which is inconvenient. Therefore, by controlling the field of view of camera 220 to completely cover the width of the battery cell 10 under test, the number of movements of the battery cell 10 or camera 220 can be reduced.

[0024] Of course, in some other embodiments, if the field of view of the camera 220 can completely cover the large area of ​​the battery cell 10 under test, the battery cell carrying component 100 does not need to move during the testing process of the battery cell 10 under test.

[0025] D1 mm can be, for example, 180mm, 182mm, 184mm, 186mm, 188mm, 190mm, 192mm, 194mm, 196mm, 198mm, 200mm, etc.

[0026] Based on this, since the battery cell 10 under test needs to move relative to the camera 220 to capture 2.5D images of different parts of the battery cell 10, the camera 220 and the light source assembly 210 can be kept stationary while the battery cell 10 under test is moved. This avoids the camera 220 and the light source assembly 210 from repeatedly focusing during back-and-forth movement, thereby improving detection efficiency.

[0027] As mentioned above, the field of view of the camera 220 can cover the portion of the battery cell 10 under test in the width direction. The battery carrying component can move relative to the light source assembly 210 along the length direction of the battery cell 10 under test so that different parts of the large surface of the battery cell 10 under test are facing the camera 220, thereby using the camera 220 to photograph each part of the large surface of the battery cell 10 under test.

[0028] In one alternative implementation, refer again to Figure 1 Both the cell-carrying component 100 and the imaging mechanism 200 are mounted on the work platform 300, and the imaging mechanism 200 is fixed relative to the work platform 300. The work platform 300 is provided with a first guide rail 400 extending along the length direction of the cell 10 to be tested. The cell-carrying component 100 is slidably connected to the first guide rail 400 relative to the first guide rail 400 along the extension direction of the first guide rail 400. After a portion of the large surface of the cell 10 to be tested has been photographed, the cell-carrying component 100 can be moved a certain distance relative to the first guide rail 400 so that the other portion of the large surface is facing the lampshade 211.

[0029] It is worth mentioning that, such as Figure 5 As shown, at least two cell-carrying components 100 can be set on the work platform 300. When one of the cell-carrying components 100 is holding a cell 10 to be tested for inspection, the other cell-carrying components 100 can be used as backups. After the preceding cell 10 to be tested has been photographed, the corresponding cell-carrying component 100 is removed, and the adjacent cell-carrying component 100 can move with the next cell 10 to be tested to face the lamp cover 211. Thus, the testing of each cell 10 to be tested can be quickly connected, thereby improving the testing efficiency.

[0030] refer to Figure 6 The cell-carrying component 100 may include a carrier plate 101 and two clamping plates 102. The carrier plate 101 is used to place the cell 10 to be tested. The two clamping plates 102 are disposed on both sides of the carrier plate 101 and are arranged along the length of the cell 10 to be tested. Each clamping plate 102 can move relative to the carrier plate 101 along the length of the cell 10 to be tested, so that the two clamping plates 102 move closer to each other or further apart. It can be understood that when the cell 10 to be tested is not placed on the carrier plate 101, the distance between the two clamping plates 102 is relatively large. When the cell 10 to be tested is placed on the carrier plate 101, the two clamping plates 102 move closer to each other to cooperate in clamping the cell 10 to be tested, ensuring that the cell 10 to be tested remains relatively fixed to the carrier plate 101 during the testing process, and avoiding affecting the testing effect.

[0031] Specifically, in the two opposing clamping plates 102, one clamping plate 102 may have a slot 1021 on the side facing the other clamping plate 102. When the clamping plate 102 contacts the side of the battery cell 10 under test, the side of the battery cell 10 under test used to connect the two large surfaces is inserted into the slot 1021. At this time, the two opposing side walls of the slot 1021 can be used to abut the two large surfaces of the battery cell 10 under test, so that the clamping plate 102 can not only position the battery cell 10 under test in the length direction, but also in the thickness direction, thus better ensuring the positioning effect of the battery cell 10 under test.

[0032] It should be noted that the depth of the card slot 1021 is relatively small, that is, the contact area between the side wall of the card slot 1021 and the large surface of the battery cell 10 under test is small, so as to avoid affecting the detection of foreign objects on the large surface.

[0033] To achieve relative movement between the clamping plate 102 and the carrier plate 101, exemplarily, continue to refer to Figure 6 A second guide rail 103 may be provided on the side of the carrier plate 101 opposite to the battery cell 10 under test, and the second guide rail 103 extends along the length direction of the battery cell 10 under test. Each clamping plate 102 can be slidably connected to the second guide rail 103 through an L-shaped connecting plate 104, so that the clamping plate 102 can slide relative to the second guide rail 103, thereby changing the distance between the two clamping plates 102.

[0034] Because a square battery cell consists of two large surfaces, foreign object detection on a square battery cell requires capturing 2.5D images of both surfaces. Based on this, as... Figure 5 As shown, the imaging mechanism 200 can be divided into two sets, with each set positioned on one side of the battery cell 10 under test. Each set of imaging mechanisms 200 can capture a 2.5D image of one large surface of the battery cell 10 under test. This simultaneous inspection of two large surfaces helps to further improve inspection efficiency.

[0035] In practice, the axes of the two lampshades 211 in the two sets of photographing mechanisms 200 can be overlapped so that when the battery cell 10 under test moves, the camera 220 on each side can capture the entire image.

[0036] Alternatively, in some other embodiments, refer to Figure 7 The imaging mechanism 200 can be a set, and the cell-carrying component 100 can include a rotating mechanism (not shown in the figure). The rotating mechanism can drive the cell 10 under test to rotate so that the two large surfaces of the cell 10 under test are respectively facing the imaging mechanism 200, thereby completing the detection of the two large surfaces of the cell 10 under test in sequence. Thus, the detection of the cell 10 under test in a relatively small space can be realized.

[0037] In some embodiments, replay Figure 3The lampshade 211 contains four light sources 212, which are evenly distributed around the inner wall of the lampshade 211. The four light sources 212 are lit sequentially. In this case, the camera 220 can capture four 2.5D images at four illumination angles: 0°, 90°, 180°, and 270°. The four images are then processed and fused into six images for analysis, allowing for a more accurate determination of whether there are foreign objects on the surface of the battery cell 10 under test.

[0038] In some embodiments, reference Figure 8 The cell-carrying component 100 can be used to place cylindrical cells, meaning that the detection device in this embodiment can be used to detect cylindrical cells. At this time, the cell-carrying component 100 can also be used to drive the cylindrical cell to rotate around the axis of the cylindrical cell, and the camera 220 can be used to capture a 2.5D image of the cylindrical surface of the cell 10 under test.

[0039] For details, please refer to Figure 9 In this embodiment, the distance d4 mm between the lampshade 211 and the large surface of the battery cell 10 under test is less than or equal to 10 mm, so as to maintain a certain gap between the lampshade 211 and the battery cell 10 under test. This gap ensures the uniformity of the diffused light field, eliminating direct light and glare, while also satisfying the focusing and field-of-view coverage of the camera 220, and preventing shadows from interfering with the identification of foreign objects on the surface of the battery cell 10 under test. Furthermore, maintaining a certain gap between the lampshade 211 and the battery cell 10 under test also facilitates the placement and removal of the battery cell 10 under test, and prevents the battery cell 10 from being damaged by heat due to being too close to the light source 212.

[0040] In practical applications, d4 mm can be 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc. The specific d4 mm can be adaptively designed according to factors such as the camera 220 parameters and the model of the battery cell under test.

[0041] In one optional implementation, the light source 212 can be a white light source. Correspondingly, the camera 220 can be a 16K line scan camera, and the lens of the camera 220 can be a 20mm focal length lens. Since the cylindrical surface of the cylindrical battery cell is a continuous curved surface, it is necessary to cover the entire circumference without blind spots during imaging. Moreover, the cylindrical surface of the cylindrical battery cell is mostly made of highly reflective materials. By selecting a 16K line scan camera for the camera 220 and using a white light source, not only can the entire circumference be covered without blind spots, avoiding missed detections, but foreign objects on the surface of the battery cell 10 under test can also be accurately identified, improving detection accuracy. At the same time, it can suppress high reflectivity interference and solve the problem of glare in curved surface imaging, thereby further improving detection efficiency.

[0042] At this time, the distance d5 mm between the camera 220 and the large surface of the battery cell 10 under test can be 150mm~200mm to meet the focusing and field of view coverage of the camera 220 and avoid shadows interfering with the identification of foreign objects on the surface of the battery cell 10 under test. Specifically, d5 mm can be 150mm, 155mm, 160mm, 165mm, 170mm, 175mm, 180mm, 185mm, 190mm, 195mm, 200mm, etc.

[0043] The distance d6 mm between the light source 212 and the large surface of the battery cell 10 under test can be 15mm to 30mm. This ensures that there is a certain distance between the light source 212 and the bottom of the lamp cover 211, allowing the light emitted by the light source 212 to pass through the inner wall of the lamp cover 211 multiple times, thus ensuring the uniformity of the light and improving the quality of the captured image. Specifically, d6 mm can be 15mm, 15.5mm, 16mm, 17mm, 18.5mm, 19.5mm, 21mm, 22.5mm, 24mm, 25mm, 26mm, 28mm, 30mm, etc.

[0044] Furthermore, in this embodiment, reference continues to be made to Figure 9 The optical axis of the camera 220 lens and the axis of the lamp cover 211 can be set at a certain angle α, where α is 2°~8°. Since the cylindrical surface of the cylindrical battery cell has a high reflectivity, slightly tilting the lens of the camera 220 can not only suppress reflections and eliminate glare interference, but also optimize the field of view coverage and reduce imaging distortion, thereby ensuring image quality. In this way, subsequent image processing can more accurately identify metallic foreign objects on the surface of the battery cell 10 under test, thus improving detection accuracy.

[0045] For example, α can be 2°, 2.5°, 3°, 3.5°, 4°, 4.5°, 5°, 5.5°, 6°, 6.5°, 7°, 7.5°, 8°, etc.

[0046] Furthermore, the field of view of the camera 220 in this embodiment is D2 mm. D2mm, where D2 mm is 140mm~150mm. On the one hand, this ensures high pixel density in the images captured by the camera 220, thereby guaranteeing image quality and facilitating accurate identification of foreign objects on the surface of the battery cell 10 under test during subsequent image processing. On the other hand, limiting the field of view to this range ensures that the battery cell 10 under test is completely within the field of view of the camera 220, eliminating the need for relative movement between the battery cell 10 and the camera 220.

[0047] D2 mm can be, for example, 140mm, 141mm, 142mm, 143mm, 144mm, 145mm, 146mm, 147mm, 148mm, 149mm, 150mm, etc.

[0048] In order to enable the rotation of the battery cell 10 under test, in one optional implementation scheme, refer to Figure 8 and Figure 10 The cell-carrying component 100 may include a first roller 105 and a second roller 106 spaced apart. The first roller 105 and the second roller 106 are arranged in parallel, and the axis of the first roller 105 and the axis of the second roller 106 are both parallel to the axis of the cell 10 under test. The distance between the first roller 105 and the second roller 106 is smaller than the diameter of the cell 10 under test, so that when the cell 10 under test is placed on the cell-carrying component 100, a portion of the cell 10 under test is accommodated in the space between the first roller 105 and the second roller 106, and the cell 10 under test is in contact with the first roller 105 and the second roller 106 respectively, and the cell 10 under test is tangent to the first roller 105 and the second roller 106 respectively. At this time, the contact between the cell 10 under test and the first roller 105 can be regarded as line contact, and the contact between the cell 10 under test and the second roller 106 can also be regarded as line contact.

[0049] The cell-carrying component 100 may further include a driving component 107 and a transmission component 108. The driving component 107 may be connected to the first roller 105 to drive the first roller 105 to rotate around its own axis. The first roller 105 may be connected to the second roller 106 via the transmission component 108. When the first roller 105 rotates around its own axis, it can drive the second roller 106 to rotate around its own axis. Furthermore, the rotation directions of the first roller 105 and the second roller 106 are the same, thereby driving the cell 10 under test to rotate around its axis.

[0050] The transmission component 108 may include, for example, a driving gear 1081, a driven gear 1082, and a timing belt 1083. The first roller 105 is connected to the driving gear 1081, and the second roller 106 is connected to the driven gear 1082. The timing belt 1083 connects the driving gear 1081 and the driven gear 1082. When the driving component 107 drives the first roller 105 to rotate, it drives the driving gear 1081 to rotate as well. The driving gear 1081 transmits power to the driven gear 1082 via the timing belt 1083, and then to the second roller 106, causing the second roller 106 to rotate synchronously.

[0051] Furthermore, the cell-carrying component 100 may also include two limiting plates 109 disposed between the first roller 105 and the second roller 106, the two limiting plates 109 being arranged along the axial direction of the first roller 105. When the battery under test is placed on the first roller 105 and the second roller 106, the two limiting plates 109 can respectively contact the two ends (top and bottom) of the battery cell under test 10, thereby limiting the battery cell under test 10 in the axial direction and preventing the battery cell under test 10 from leaving the field of view of the camera 220 during rotation.

[0052] In some embodiments, such as Figure 2 As shown, the imaging mechanism 200 may also include a light shield 230, which is fixed to the side of the lampshade 211 facing the camera 220. Specifically, the light shield 230 may be arranged around the through hole 2111 so that the light shield 230 can form a small light-blocking space to prevent light inside the lampshade 211 from being emitted from the through hole 2111 at the top of the lampshade 211, thus avoiding light waste.

[0053] The lens hood 230 may, for example, consist of three light-shielding plates connected in sequence, forming a U-shaped structure so that one side of the lens hood 230 has an opening. In this way, the camera 220 can be placed inside the lens hood 230 through the opening, and the camera 220 can also be easily removed from the lens hood 230.

[0054] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this utility model without departing from the spirit and scope of this utility model. Therefore, if these modifications and variations of this utility model fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A device for detecting foreign matter on the surface of a battery cell, characterized in that, It includes a cell carrier component (100) and a photographing mechanism (200), the photographing mechanism (200) including a light source assembly (210) and a camera (220); The cell carrier component (100) is used to place the cell to be tested (10). The light source assembly (210) is disposed on one side of the battery cell support component (100). The light source assembly (210) includes a lampshade (211) and a plurality of light sources (212). The plurality of light sources (212) are spaced apart on the inner wall of the lampshade (211) around the axis of the lampshade (211). The plurality of light sources (212) are connected in parallel. When the light source (212) is lit, the light emitted by the light source (212) forms a dome light. The camera (220) is disposed on the side of the light source assembly (210) away from the cell support component (100). The lampshade (211) has a through hole (2111) coaxially disposed with the lampshade (211) on the side facing the camera (220). The camera (220) is used to capture a 2.5D image of the surface of the cell under test (10) through the through hole (2111) when the multiple light sources (212) are lit respectively.

2. The foreign matter detection device on the surface of the battery cell according to claim 1, characterized in that, The cell under test (10) is a square cell, and the camera (220) is used to capture a 2.5D image of the large surface of the cell under test (10); The light source (212) is an infrared light source with a wavelength of 760nm~1700nm; The field of view of the camera (220) is D1 mm. D1mm, where D1 mm is 180mm~200mm.

3. The foreign matter detection device on the surface of the battery cell according to claim 2, characterized in that, The distance d1 mm between the lampshade (211) and the large surface of the battery cell (10) under test is 10 mm to 70 mm; The distance d2 mm between the camera (220) and the large surface of the battery cell (10) under test is 340 mm to 400 mm, and / or the distance d3 mm between the light source (212) and the large surface of the battery cell (10) under test is 140 mm to 200 mm.

4. The foreign matter detection device on the surface of the battery cell according to claim 2, characterized in that, The cell carrier component (100) can move relative to the light source assembly (210) along the length direction of the cell under test (10) so that different parts of the large surface of the cell under test (10) are facing the camera (220).

5. The foreign matter detection device on the surface of the battery cell according to claim 2, characterized in that, The cell support component (100) includes a carrier plate (101) and two clamping plates (102). The carrier plate (101) is used to place the battery cell (10) under test. The two clamps (102) are disposed on both sides of the carrier plate (101) along the length direction of the battery cell (10) to be tested. The clamps (102) can move relative to the carrier plate (101) along the length direction of the battery cell (10) to allow the two clamps (102) to cooperate in clamping the battery cell (10) to be tested.

6. The foreign matter detection device on the surface of the battery cell according to claim 5, characterized in that, One of the clamping plates (102) has a slot (1021) on the side facing the other clamping plate (102), and the two opposite sidewalls of the slot (1021) are respectively used to abut against the two large surfaces of the battery cell (10) under test.

7. The foreign matter detection device on the surface of the battery cell according to claim 2, characterized in that, The imaging mechanism (200) consists of two sets, which are respectively disposed on both sides of the battery cell (10) under test. Each set of imaging mechanisms (200) is used to capture a 2.5D image of a large surface of the battery cell (10) under test; or, The cell-carrying component (100) includes a rotating mechanism for driving the cell under test (10) to rotate so that the two large surfaces of the cell under test (10) are respectively facing the photographing mechanism (200).

8. The foreign matter detection device on the surface of the battery cell according to claim 1, characterized in that, The cell under test (10) is a cylindrical cell, and the cell support component (100) is used to drive the cell under test (10) to rotate around the axis of the cell under test (10), and the camera (220) is used to capture a 2.5D image of the cylindrical surface of the cell under test (10). The light source (212) is a white light source; The field of view of the camera (220) is D2 mm. D2mm, where D2 mm is 140mm~150mm.

9. The foreign matter detection device on the surface of the battery cell according to claim 8, characterized in that, The distance d4 mm between the lampshade (211) and the cylindrical surface of the battery cell (10) under test is less than or equal to 10 mm; The distance d5 mm between the camera (220) and the cylindrical surface of the battery cell (10) under test is 150 mm to 200 mm, and / or the distance d6 mm between the light source (212) and the cylindrical surface of the battery cell (10) under test is 15 mm to 30 mm.

10. The foreign matter detection device on the surface of the battery cell according to claim 9, characterized in that, The cell support component (100) includes a first roller (105) and a second roller (106) spaced apart. The axis of the first roller (105) and the axis of the second roller (106) are parallel to the axis of the cell (10) under test, respectively. The distance between the first roller (105) and the second roller (106) is smaller than the diameter of the cell (10) under test. A portion of the battery cell (10) to be tested is housed in the space between the first roller (105) and the second roller (106), and the battery cell (10) to be tested is tangent to the first roller (105) and the second roller (106) respectively; The first roller (105) and the second roller (106) can rotate around their own axes respectively to drive the battery cell (10) under test to rotate around its own axis.

11. The foreign matter detection device on the surface of the battery cell according to claim 10, characterized in that, The cell support component (100) further includes two limiting plates (109) disposed between the first roller (105) and the second roller (106). The two limiting plates (109) are arranged along the axial direction of the first roller (105), and the two limiting plates (109) are respectively used to contact the two ends of the cell (10) to be tested.

12. The foreign matter detection device on the surface of the battery cell according to claim 8, characterized in that, The optical axis of the lens of the camera (220) has an angle α with the axis of the lampshade (211), where α is 2°~8°.

13. The foreign matter detection device on the surface of the battery cell according to claim 1, characterized in that, The photographing mechanism (200) also includes a light shield (230) fixed to the side of the lampshade (211) facing the camera (220), and the camera (220) is located inside the light shield (230).

Images