A battery coating defect detection device

Abstract

The present invention discloses a battery coating defect detection device, which belongs to the field of defect detection. The battery coating defect detection device comprises a transmission component and a detection component, wherein the transmission component is used to transmit the battery pole piece to be detected; the detection component comprises an image sensor and a light source component, wherein the light source component comprises a light emitting component; the light emitting component is used to emit light inclined relative to the battery surface to the surface of the battery pole piece to generate a bright field; the image sensor is used to collect an image of the surface of the battery pole piece in the bright field. The battery coating defect detection device of the present invention can effectively highlight the defect characteristics, which is conducive to improving the defect detection effect.

Description

Technical Field

[0001] The present invention relates to the field of defect detection, and in particular to a battery coating defect detection device. Background Art

[0002] At present, in the process of battery manufacturing, a coating machine is needed to coat the battery pole piece so that the stirred slurry is evenly coated on the current collector. The coating effect has an important impact on the battery capacity, internal resistance and safety. In the process of battery coating, due to the selection of coating methods and different related control parameters, coating defects may exist, such as cracking, shedding, wrinkling, indentation, foil leakage, improper coating size, unevenness such as particles and pits on the surface coating of the pole piece, etc. Therefore, in order to ensure the coating quality, defect detection is required after battery coating.

[0003] However, in the prior art, battery coating defects are generally detected through manual detection methods. This detection method is inefficient, prone to missed detections, and has poor detection effects. Although there are detection equipment for detecting battery coating effects in the prior art, defect recognition is not sensitive enough, which can easily lead to missed detections. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, an object of the present invention is to provide a battery coating defect detection device that can improve the detection effect.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A battery coating defect detection device, comprising:

[0007] A conveying component, used for conveying the battery pole piece to be inspected;

[0008] The detection component includes an image sensor and a light source component, wherein the light source component includes a light emitting component; the light emitting component is used to emit light inclined relative to the battery surface to the surface of the battery pole piece to generate a bright field; the image sensor is used to collect an image of the surface of the battery pole piece in the bright field.

[0009] Furthermore, the image sensor is arranged obliquely relative to the surface of the battery pole piece to be detected, and the image sensor is used to capture the image of the surface of the battery pole piece at an inclined angle.

[0010] Furthermore, the light source assembly also includes a shading plate, which is arranged between the battery pole piece and the image sensor, and the shading plate is provided with an avoidance groove; the image sensor is configured to align the acquisition field of view with the avoidance groove, thereby acquiring an image of the surface of the battery pole piece through the avoidance groove.

[0011] Further, it also includes a rack;

[0012] The light source assembly also includes a first mounting frame rotatably connected to the frame, and the light-emitting component is fixed to the first mounting frame; the first mounting frame is used to drive the light-emitting component to rotate relative to the frame, thereby changing the inclination angle of the light-emitting component relative to the surface of the battery electrode.

[0013] Further, it also includes a rack;

[0014] The detection assembly further includes a second mounting frame rotatably connected to the frame; the image sensor is fixed to the frame; the second mounting frame is used to drive the image sensor to rotate relative to the frame, so that the inclination angle of the image sensor relative to the battery electrode sheet changes;

[0015] The light source assembly also includes a first mounting frame rotatably connected to the frame, and the shading plate is fixed to the first mounting frame; the first mounting frame is used to drive the shading plate to rotate relative to the frame, thereby changing the position of the avoidance groove.

[0016] Furthermore, it also includes an encoder and a control system; when the transmission component drives the battery pole to move, the battery pole drives the encoder to rotate; the encoder is used to send a photo signal to the control system during rotation, and the control system is used to control the image sensor to take photos after receiving the photo signal.

[0017] Furthermore, the light source is a line-scanning strip light source.

[0018] Furthermore, the image sensor is a line array camera.

[0019] Furthermore, it also includes a data processing unit and an early warning unit;

[0020] The data processing unit is used to receive the images sent by the image sensor, and to perform stitching and defect recognition on the collected images;

[0021] The early warning unit is used to issue a defect early warning according to the defect identification result of the data processing unit.

[0022] Compared with the prior art, the beneficial effects of the present invention are: it is helpful to highlight coating defects, can improve the comprehensiveness of defect features in images collected by image sensors, can reduce the missed detection rate, and is helpful to improve the coating defect detection effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The structure of the battery coating defect detection device of the present invention is shown in FIG. Figure 1 ;

[0024] Figure 2 for Figure 1 A magnified view of part A in FIG.

[0025] Figure 3 The structure of the battery coating defect detection device of the present invention is shown in FIG. Figure 2 ;

[0026] Figure 4 for Figure 3 A magnified view of part B in FIG.

[0027] Figure 5 It is a detection flow chart of the battery coating defect detection equipment of the present invention;

[0028] Figure 6 It is a working principle diagram of the battery coating defect detection device of the present invention;

[0029] Figure 7 It is a schematic diagram of the operation interface of the control system of the present invention;

[0030] In the figure: 10, transmission component; 21, image sensor; 221, light-emitting element; 222, light shielding plate; 2221, avoidance groove; 31, first mounting frame; 32, second mounting frame; 90, battery electrode. DETAILED DESCRIPTION

[0031] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0032] See also Figure 1-7 , this embodiment provides a battery coating defect detection device, including: a frame, a conveying component 10 and a detection component; in this embodiment, the conveying component 10 is a conveying roller group formed by a plurality of conveying rollers, and the conveying rollers are installed on the frame, and the flexible battery electrode 90 to be detected is conveyed along the length direction of the battery electrode 90 under the rotation of the conveying rollers; the detection component includes an image sensor 21 and a light source component, please refer to Figure 3 , 4 As shown, the light source assembly includes a light emitting element 221; the light emitting element 221 is used to emit light inclined relative to the battery surface to the surface of the battery pole piece 90 to generate a bright field; the image sensor 21 is used to collect an image of the surface of the battery pole piece 90 in the bright field.

[0033] In this embodiment, the image sensor 21 is an industrial CCD camera, specifically a black-and-white linear array camera; in some other embodiments, the image sensor 21 may also be a color linear array camera or an area array camera.

[0034] In this embodiment, the light emitting element 221 is an industrial light source, specifically a line-scanning strip light source.

[0035] Based on the above structure, the present embodiment configures the light emitting element 221 to emit light inclined relative to the surface of the battery electrode 90 toward the surface of the battery electrode 90. When there are uneven defects such as bubbles, shrinkage, scratches, wrinkles, etc. on the coating layer of the battery electrode 90, the situation where the uneven defects are not obvious can be avoided, and the defect features can be effectively highlighted, so that the image captured by the image sensor 21 can include more comprehensive defect features, which can reduce the missed detection rate and effectively improve the detection effect.

[0036] See also Figure 3 , 4 Preferably, the image sensor 21 and the light-emitting element 221 in the present embodiment are configured as an offset arrangement, that is, a non-coaxial arrangement, that is, the optical path from the image sensor 21 to the battery electrode 90 is staggered with the optical path from the light-emitting element 221 to the battery electrode 90, so as to avoid glare caused by direct light hitting the surface of the battery electrode 90, especially when there is exposed metal on the surface of the battery electrode 90, so as to avoid the light emitted by the light source being directly reflected to the image sensor 21, and to avoid the defective image acquisition effect of the image sensor 21 being affected by glare.

[0037] Preferably, in order to improve the defect feature more comprehensively reflected in the captured image and improve the defect feature capture sensitivity of the image sensor 21, the image sensor 21 is tilted relative to the surface of the battery electrode 90 to be detected, and the image sensor 21 is used to capture the image of the surface of the battery electrode 90 at an inclined angle; through the setting of the above-mentioned structure, such as when there is a thin tape mistakenly affixed on the surface of the coating area, or there are tiny wrinkles on the coating area, the image sensor 21 captures the image at an inclined angle, so that even relatively small concave and convex defects can be displayed on the captured image captured by the image sensor 21, which is beneficial to improve the recognition rate and reduce the missed detection rate.

[0038] See also Figure 2 Preferably, in order to prevent stray light from affecting the image acquisition of the image sensor 21, the light source assembly also includes a light shielding plate 222, which is arranged between the battery pole piece 90 and the image sensor 21, and the light shielding plate 222 is provided with an avoidance groove 2221; the image sensor 21 is configured to align the acquisition field of view with the avoidance groove 2221, so as to acquire the image of the surface of the battery pole piece 90 through the avoidance groove 2221.

[0039] On the basis of the above structure, in order to meet the different detection requirements of the pole piece to be detected, in this embodiment, the light source component and the detection component are configured as a structure with adjustable tilt angle, which is specifically achieved through the following structure:

[0040] See also Figure 3 , 4As shown, the defect detection equipment also includes a frame; the light source assembly also includes a first mounting frame 31 rotatably connected to the frame, and the light-emitting member 221 is fixed to the first mounting frame 31; the first mounting frame 31 is used to drive the light-emitting member 221 to rotate relative to the frame, so that the inclination angle α of the light-emitting member 221 relative to the surface of the battery electrode 90 changes; the shading plate 222 is fixed to the first mounting frame 31; the first mounting frame 31 is used to drive the shading plate 222 to rotate relative to the frame, so that the position of the avoidance groove 2221 changes; the detection assembly also includes a second mounting frame 32 rotatably connected to the frame; the image sensor 21 is fixed to the frame; the second mounting frame 32 is used to drive the image sensor 21 to rotate relative to the frame, so that the inclination angle β of the image sensor 21 relative to the battery electrode 90 changes.

[0041] In this embodiment, angle α and angle β are configured to be unequal, so as to prevent the leakage foil on the surface of the battery electrode 90 from directly reflecting the light to the image sensor 21 after the light is emitted by the light source, causing glare and affecting the image acquisition effect.

[0042] In some other embodiments, glare can be avoided by providing a polarizing plate on the image sensor 21 .

[0043] Specifically, when the light-emitting component 221 rotates, the angle α can be adjusted to effectively highlight the defects; when the image sensor 21 rotates, the angle β can be adjusted so that the image sensor 21 can capture some defect features that are difficult to capture, thereby improving the recognition rate; when the light-shielding plate 222 rotates, the position of the avoidance groove 2221 can be adjusted so that the image sensor 21 can capture the image of the surface of the battery electrode 90 through the avoidance groove 2221.

[0044] The detection speed of this embodiment is ≤5m / min, the detection width is ≤450mm, the detection accuracy is 0.5mm, and the line array camera used in this embodiment is an 8k camera.

[0045] Preferably, it also includes an encoder and a control system; when the transmission component 10 drives the battery pole piece 90 to move, the battery pole piece 90 triggers the encoder to rotate; the encoder sends a photo signal to the control system, and the control system is used to control the image sensor 21 to take a photo after receiving the photo signal.

[0046] Preferably, it also includes a data processing unit and an early warning unit; the data processing unit is used to receive images sent by the image sensor 21, and to stitch and identify defects in the collected images; the early warning unit is used to issue defect early warnings based on the defect identification results of the data processing unit.

[0047] See also Figure 5 , 6 , the battery coating defect detection process of this embodiment is:

[0048] After the electrode is coated and dried, the encoder triggers the linear array camera to take pictures. The data processing unit receives the image sent by the linear array camera, and splices the collected images to obtain the target image, extracts defects from the target image, obtains the defect area, calculates the characteristic value of the defect area, classifies and matches the defects according to the characteristic value, determines the defect type, and determines whether the defect characteristic threshold exceeds the preset value. If the defect characteristic value exceeds the threshold, the data processing unit sends a warning signal to the warning unit, and the warning unit performs a direct warning shutdown operation, or controls the marking component to mark the defect.

[0049] The data processing unit in this embodiment uses an algorithm that combines deep learning and image feature analysis to achieve the identification of electrode coating defects.

[0050] See also Figure 7 When using the battery coating defect equipment of this embodiment for detection, the defect type to be detected, the defect threshold value, etc. can be selected on the control system.

[0051] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A battery coating defect detection device, characterized in that: include: The rack and conveying assembly are used to convey the battery pole pieces to be inspected; The detection component includes an image sensor and a light source component, wherein the light source component includes a light emitting member; the light emitting member is used to emit light inclined relative to the battery surface to the surface of the battery pole piece to generate a bright field; the image sensor is arranged obliquely relative to the surface of the battery pole piece, and is used to collect an image of the surface of the battery pole piece in the bright field at an inclined angle; The light emitting element and the image sensor are arranged in an offset manner, the light emitting element has an inclination angle α relative to the surface of the battery electrode, and the image sensor has an inclination angle β relative to the surface of the battery electrode, wherein the angle α is not equal to the angle β; The light source assembly further comprises a light shielding plate, which is arranged between the battery pole piece and the image sensor, and the light shielding plate is provided with an avoidance groove; The light source assembly further comprises a first mounting frame rotatably connected to the frame, one end of the light emitting member is fixed to the first mounting frame, and the other end thereof is a free end, and the free end of the light emitting member has a light emitting surface; one end of the light shielding plate is fixed to the first mounting frame, and the other end thereof is a free end, and the avoidance groove is located at the free end of the light shielding plate, wherein the vertical distance between the light emitting surface of the light emitting member and the surface of the battery pole piece is greater than the vertical distance between the avoidance groove and the surface of the battery pole piece; the first mounting frame is used to drive the light emitting member and the light shielding plate to rotate relative to the frame, so that the inclination angle of the light emitting member relative to the surface of the battery pole piece changes, and at the same time, the position of the avoidance groove changes; The detection component also includes a second mounting frame rotatably connected to the frame; the image sensor is fixed to the second mounting frame; the second mounting frame is used to drive the image sensor to rotate relative to the frame, so that the inclination angle of the image sensor relative to the battery electrode piece changes; the image sensor is configured to collect a field of view aligned with the avoidance groove, so as to collect an image of the surface of the battery electrode piece through the avoidance groove.

2. The battery coating defect detection device according to claim 1, characterized in that: The image sensor is arranged obliquely relative to the surface of the battery pole piece to be detected, and the image sensor is used to collect the image of the surface of the battery pole piece at an inclined angle.

3. The battery coating defect detection device according to claim 1, characterized in that: It also includes an encoder and a control system; when the transmission component drives the battery pole to move, the battery pole drives the encoder to rotate; the encoder is used to send a photo signal to the control system when rotating, and the control system is used to control the image sensor to take photos after receiving the photo signal.

4. The battery coating defect detection device according to claim 1, characterized in that: The light source is a line-scanning strip light source.

5. The battery coating defect detection device according to claim 1, characterized in that: The image sensor is a line array camera.

6. The battery coating defect detection device according to claim 1, characterized in that: It also includes a data processing unit and an early warning unit; the data processing unit is used to receive images sent by the image sensor, and to stitch and identify defects in the collected images; the early warning unit is used to issue defect early warnings based on the defect identification results of the data processing unit.

Images