Battery module bottom surface gluing device and gluing method

Abstract

The application relates to the technical field of battery manufacturing, and discloses a battery module bottom surface gluing device and a gluing method. The gluing method comprises the following steps: the battery module bottom surface gluing device clamps a battery module and turns it over, so that the bottom surface of the battery module faces the upper gluing head; an image of the bottom surface of the battery module is acquired, an actual gluing area is generated, and an actual gluing track is planned; the gluing head glues the bottom surface of the battery module according to the actual gluing track; the glue type of the bottom surface of the battery module is detected; if the detection is qualified, the battery module is turned over, so that the bottom surface faces the side away from the gluing head, and the battery module is placed on a liquid cooling plate and then transferred to a liquid cooling plate pressing process; if the detection is unqualified, the battery module is marked and waits for repair. The application can reduce the gluing area, reduce the amount of glue, and avoid glue waste. Meanwhile, the application can improve the product yield, reduce defects such as glue shortage and uneven glue layer caused by liquid cooling plate deformation, and place the battery module on the liquid cooling plate after gluing, so that the glue layer is not polluted.

Description

Technical Field

[0001] This invention relates to the field of battery manufacturing technology, specifically to a battery module bottom surface coating device and coating method. Background Technology

[0002] The thermal management performance of a battery pack directly affects the battery's charging and discharging efficiency, safety, and lifespan. As a core component of the battery pack's thermal management system, the design of the thermally conductive connection structure between the liquid cooling plate and the battery modules is crucial, impacting the overall thermal management performance of the battery pack.

[0003] Currently, the battery module and the liquid cooling plate are connected by thermally conductive adhesive. Specifically, after the liquid cooling plate is installed into the battery pack housing, thermally conductive structural adhesive is applied to the surface of the liquid cooling plate by an automatic adhesive application device. Then, the assembled battery module is hoisted into the battery pack housing, and the bottom surface of the battery module is pressed and cured with the adhesive-coated surface of the liquid cooling plate.

[0004] However, this method of applying adhesive has the following problems: First, the coating area is large, resulting in high glue consumption. This coating method involves applying glue to the entire liquid cooling plate, but the liquid cooling plate typically covers the entire bottom of the battery pack. The actual usable coating area is only the area where the bottom surface of the battery module contacts the liquid cooling plate, i.e., the area of ​​the bottom surface of the battery module. This large-area coating leads to serious material waste.

[0005] Secondly, the adhesive coating process places extremely high demands on the flatness of the liquid cooling plate, making the work very difficult. The liquid cooling plate has flatness tolerances (typically within ±0.5mm) during brazing and stamping, and large-area adhesive coating is highly sensitive to the flatness of the substrate. If the liquid cooling plate deforms beyond the tolerance, localized missing adhesive or uneven adhesive layer thickness can easily occur after lamination, leading to poor heat dissipation. In actual production, the rework rate due to adhesive coating defects caused by liquid cooling plate flatness issues is as high as 5%-10%.

[0006] Third, there is a risk of adhesive contamination. In existing production lines, the adhesive application station is separate from the module assembly station. After the adhesive is applied to the liquid cooling plate, it needs to be transferred to the module assembly station and then pressed with the battery module. During the transfer process, the adhesive layer is easily contaminated, resulting in adhesive quality defects.

[0007] Fourth, repairs are difficult. Because of the large area covered by adhesive, if a battery module malfunctions and needs to be replaced after the battery module and liquid cooling plate are assembled, the liquid cooling plate is easily damaged or a large amount of residual adhesive is left during disassembly, increasing the difficulty of repairs. Summary of the Invention

[0008] This invention provides a battery module bottom surface adhesive coating device and method to solve the problems of large coating area, high glue consumption, high cost, high process difficulty, easy contamination of adhesive layer, and high difficulty of subsequent rework in liquid cooling plate adhesive coating method.

[0009] In a first aspect, the present invention provides a method for applying adhesive to the bottom surface of a battery module, which is applied to a battery module bottom surface adhesive application device to apply adhesive to the bottom surface of the battery module, including: The battery module bottom coating device clamps the battery module and flips it so that the bottom of the battery module faces the upward coating head. Acquire an image of the bottom surface of the battery module, generate the actual adhesive application area, and plan the actual adhesive application trajectory; The adhesive applicator applies adhesive to the bottom surface of the battery module according to the actual adhesive application trajectory; The adhesive pattern on the bottom surface of the battery module is inspected; If the inspection is successful, the battery module is flipped over so that its bottom surface faces away from the adhesive applicator and placed on the liquid cooling plate. Then it is transferred to the pressing process with the liquid cooling plate. If the test fails, the battery module will be marked and await repair.

[0010] Beneficial effects: The new method of applying adhesive to the bottom surface of the battery module instead of the existing method of applying adhesive to the liquid cooling plate reduces the adhesive application area and the amount of adhesive used, thus avoiding significant adhesive waste. The flatness and consistency of the bottom surface of the battery module are far superior to those of the brazed liquid cooling plate. Furthermore, the reduced adhesive application area lowers the flatness requirements for the battery module's bottom surface, resulting in a higher pass rate and reducing defects such as insufficient adhesive or uneven adhesive layers caused by liquid cooling plate deformation. After adhesive application, in-situ testing can be performed using a testing instrument, allowing for timely rework if problems are found. Moreover, the battery module is placed directly on the liquid cooling plate after adhesive application, preventing the adhesive layer from being exposed and reducing the risk of contamination. Even if the battery module needs repair or replacement after assembly, the smaller adhesive application area simplifies the repair process and minimizes the risk of damaging the liquid cooling plate.

[0011] In an optional embodiment, the steps of acquiring an image of the bottom surface of the battery module, generating the actual adhesive application area, and planning the actual adhesive application trajectory include: Take a picture to capture an image of the bottom surface of the battery module; The image is preprocessed; The actual outline of the battery module is obtained from the preprocessed image; The actual adhesive application area is generated based on the actual contour and preset process parameters; The deviation data is calculated by comparing the actual contour with the theoretical contour. The actual adhesive application trajectory is generated based on the adhesive application pattern and the deviation data.

[0012] Beneficial effects: The actual contour is obtained through image acquisition and processing, and then compared to calculate the deviation data, which facilitates the subsequent accurate planning of the glue application trajectory and improves the glue application accuracy.

[0013] In an optional embodiment, the step of preprocessing the image includes: Convert the image to grayscale, transforming it into a black and white image; Denoising the image to eliminate noise; Enhance the contrast between the battery module area and the background in the image; The image is binarized and converted into a black and white binary image.

[0014] Beneficial effects: Preprocessing the image helps to accurately identify the actual contour of the pool module.

[0015] In an optional embodiment, the step of obtaining the actual contour of the battery module based on the preprocessed image includes: Detect the image after binarization; Based on the brightness difference between each pixel in the image and its surrounding pixels, pixels with drastic brightness changes are identified as edge points; Connect all edge points to obtain the actual outline of the battery module.

[0016] In an optional embodiment, the step of calculating the deviation data based on the comparison between the actual contour and the theoretical contour includes: The corner points of the actual contour are used as the first reference point, and the corner points of the theoretical contour are used as the second reference point. The positions of the corresponding first reference point and second reference point are compared to obtain the displacement deviation value of the actual contour relative to the theoretical contour on the reference plane. The reference plane is the plane containing the length direction and the width direction of the battery module. The line connecting any two diagonal corner points on the actual contour is taken as the first reference line, and the line connecting any two diagonal corner points on the theoretical contour is taken as the second reference line. The angle difference between the first reference line and the second reference line is calculated to obtain the rotational deviation value of the actual contour relative to the theoretical contour on the reference plane.

[0017] In an optional embodiment, in the step of generating the actual adhesive application area based on the actual contour and preset process parameters, the preset process parameters are a safety distance between the actual adhesive application area and the actual contour.

[0018] In an optional embodiment, in the step of generating the actual adhesive trajectory based on the adhesive application pattern and the deviation data, the adhesive application pattern is a rectangular spiral pattern, a parallel line pattern, or a serpentine line pattern.

[0019] In an optional embodiment, during the step of applying adhesive to the bottom surface of the battery module according to the actual adhesive application trajectory, the distance between the adhesive nozzle of the adhesive application head and the bottom surface of the battery module is maintained at a preset distance.

[0020] In an optional embodiment, the step of detecting the adhesive pattern on the bottom surface of the battery module includes: The detector moves along the adhesive application trajectory and scans the cross-sectional profile of the adhesive line. Obtain data on glue height, glue width, and glue path continuity based on the scanning results; The acquired data is compared with preset standards.

[0021] Secondly, the present invention also provides a battery module bottom surface adhesive coating device, applied to the aforementioned adhesive coating method, comprising: Organism; A clamping mechanism, disposed on the body, is used to clamp and flip the battery module; A lifting drive mechanism is disposed on the machine body, and its drive end is connected to the clamping mechanism, which is adapted to drive the clamping mechanism to move along the height direction of the battery module. An adhesive application drive mechanism is mounted on the machine body; The glue applicator head is connected to the drive end of the glue applicator drive mechanism and is located above the battery module. The detector is connected to the drive end of the adhesive application drive mechanism; A visual positioning mechanism is connected to the drive end of the adhesive application drive mechanism; The adhesive application driving mechanism is adapted to drive the adhesive application head, the detector and the vision positioning mechanism to move along the length and width directions of the battery module; The control system is electrically connected to the clamping mechanism, the lifting drive mechanism, the glue application drive mechanism, the glue application head, the detector, and the vision positioning mechanism.

[0022] Beneficial effects: Since the adhesive coating device for the bottom surface of the battery module is applied to the adhesive coating method for the bottom surface of the battery module, it has the same technical effect and will not be described in detail here. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1This is a schematic diagram of a battery module bottom coating device according to an embodiment of the present invention; Figure 2 for Figure 1 Enlarged view of section A; Figure 3 This is a front view of a battery module bottom coating device according to an embodiment of the present invention; Figure 4 for Figure 1 Enlarged view of section B; Figure 5 This is a rear view of a battery module bottom surface adhesive coating device according to an embodiment of the present invention; Figure 6 for Figure 1 Enlarged view of section C; Figure 7 This is a schematic diagram from another perspective of a battery module bottom coating device according to an embodiment of the present invention; Figure 8 for Figure 1 Enlarged view of section D; Figure 9 This is a schematic diagram from another perspective of a battery module bottom coating device according to an embodiment of the present invention; Figure 10 for Figure 1 Enlarged view of section E in the middle.

[0025] Explanation of reference numerals in the attached figures: 1. Organism; 2. Clamping mechanism; 21. Mounting plate; 22. Clamping plate; 23. Clamping drive component; 24. Tilting drive component; 25. First track; 26. Rotating seat; 3. Lifting drive mechanism; 31. Mounting column; 32. Connecting column; 33. Lifting drive component; 34. Gear; 35. Rack; 36. Second track; 4. Adhesive application drive mechanism; 41. Mounting base; 42. Third track; 43. Sliding seat; 44. Connecting plate; 45. Fourth track; 5. Glue applicator; 6. Detector; 7. Visual positioning mechanism; 8. Control system; 9. Battery module; 10. Liquid cooling plate. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The following is combined with Figures 1 to 10 The following describes embodiments of the present invention.

[0028] According to an embodiment of the present invention, in one aspect, a battery module bottom surface adhesive coating device is provided, which is applied to the battery module bottom surface adhesive coating method, including: a body 1, a clamping mechanism 2, a lifting drive mechanism 3, an adhesive coating drive mechanism 4, an adhesive coating head 5, a detector 6, a vision positioning mechanism 7, and a control system 8. A clamping mechanism 2 is mounted on the machine body 1 and is used to clamp and flip the battery module 9. A lifting drive mechanism 3 is mounted on the machine body 1, and its drive end is connected to the clamping mechanism 2, which is suitable for driving the clamping mechanism 2 to move along the height direction of the battery module 9. A glue application drive mechanism 4 is mounted on the machine body 1. A glue application head 5 is connected to the drive end of the glue application drive mechanism 4 and is located above the battery module 9. A detector 6 is connected to the drive end of the glue application drive mechanism 4. A vision positioning mechanism 7 is connected to the drive end of the glue application drive mechanism 4. The glue application drive mechanism 4 is suitable for driving the glue application head 5, the detector 6, and the vision positioning mechanism 7 to move along the length and width directions of the battery module 9. A control system 8 is electrically connected to the clamping mechanism 2, the lifting drive mechanism 3, the glue application drive mechanism 4, the glue application head 5, the detector 6, and the vision positioning mechanism 7.

[0029] Specifically, such as Figure 1 As shown, the body 1 is the main frame of the adhesive application device and also the support for various mechanisms. The clamping mechanism 2 is mounted on the body 1 and can clamp and flip the battery module 9. In one embodiment, as... Figure 3 , Figure 4 , Figure 7 , Figure 8As shown, the clamping mechanism 2 includes: a mounting plate 21, clamping plates 22, a clamping drive component 23, and a flipping drive component 24. The mounting plate 21 is connected to the lifting drive mechanism 3, so the entire clamping mechanism 2 can be lifted and lowered. Two clamping plates 22 are located at two ends on one side of the mounting plate 21. The two clamping plates 22 can clamp the battery module 9 from both sides. To achieve the clamping action, at least one clamping plate 22 can move linearly along the length of the battery module 9. The clamping drive component 23 is preferably a cylinder, which is mounted on the mounting plate 21, and its driving end is connected to the clamping plate 22. One cylinder can drive one clamping plate 22 to move; two cylinders can drive both clamping plates 22 to move respectively. In this embodiment, one cylinder is provided, which can drive one clamping plate 22 to move, thereby changing the distance between the two clamping plates 22 for clamping. The mounting plate 21 is also provided with a first track 25, and the clamping plate 22 is slidably connected to the first track 25 to improve the stability of the movement. The flipping drive 24 is preferably a motor. The flipping drive 24 is set on one of the clamping plates 22. A rotating seat 26 is rotatably set on the clamping plate 22. After the two clamping plates 22 clamp the battery module 9, the two rotating seats 26 respectively abut against the two ends of the battery module 9. The driving end of the flipping drive 24 is connected to one of the rotating seats 26 to drive the rotating seat 26 to rotate, thereby driving the entire battery module 9 to rotate. The battery module 9 transported from the previous process is clamped by the clamping drive 23 driven by the two clamping plates 22, and then the flipping drive 24 drives the battery module 9 to rotate 180°, flipping the bottom surface of the battery module 9 from its original downward position to face upward. It should be noted that the bottom surface of the battery module 9 refers to the side of the battery module 9 connected to the liquid cooling plate 10, that is, the bottom surface of the battery module 9 when it is in normal use.

[0030] like Figure 5 , Figure 6 , Figure 9 , Figure 10 As shown, the lifting drive mechanism 3 includes: a mounting column 31, a connecting column 32, a lifting drive component 33, a gear 34, a rack 35, and a second track 36. The mounting column 31 is connected to the body 1. The lifting drive component 33 is preferably a motor and is mounted on the connecting column 32. The mounting column 31 is provided with a rack 35 and a second track 36, both of which extend along the height direction of the battery module 9. The connecting column 32 is slidably connected to the second track 36. The output end of the lifting drive component 33 is connected to the gear 34. Specifically, transmission can be achieved through a bevel gear 34, which meshes with the rack 35. The mounting plate 21 in the clamping mechanism 2 is connected to the lower end of the connecting column 32. When the lifting drive component 33 starts and drives the gear 34 to rotate, it can drive the gear 34 to move on the rack 35, thereby driving the connecting column 32 to slide on the second track 36, which in turn drives the entire clamping mechanism 2 to lift and lower.

[0031] like Figure 1 , Figure 2 As shown, the adhesive application drive mechanism 4 includes: a mounting base 41, a third track 42, a sliding seat 43, a connecting plate 44, a first linear drive component, a fourth track 45, and a second linear drive component. The mounting base 41 is connected to the bottom end of the mounting post 31. The third track 42 is disposed on the mounting base 41, extending along the length of the battery module 9. The sliding seat 43 is slidably disposed on the third track 42. The first linear drive component is disposed on the mounting base 41, with its drive end connected to the sliding seat 43. The first linear drive component is preferably a cylinder. The connecting plate 44 is disposed on the sliding seat 43, and two fourth tracks 45 are spaced apart along the length of the battery module 9. The fourth tracks 45 extend along the width of the battery module 9. The two sides of the adhesive application head 5 are slidably connected to the two fourth tracks 45 respectively. The second linear drive component is disposed on the connecting plate 44, with its drive end connected to the adhesive application head 5. The second linear drive component is preferably a cylinder. The adhesive application drive mechanism 4 can drive the adhesive application head 5 to move along the length and width directions of the battery module 9 to apply adhesive to the bottom surface of the battery module 9. The adhesive application head 5 is also equipped with a distance sensor to detect the distance between the nozzle and the bottom surface of the battery module 9.

[0032] Furthermore, it is also equipped with a glue bucket, a glue pump, and a pipeline. The pipeline connects the glue bucket, the glue pump, and the glue application head 5. The glue pump is used to pump the glue from the glue bucket to the glue application head 5. A flow monitor is also connected to the pipeline to detect the glue flow rate.

[0033] like Figure 2 As shown, the inspection instrument 6 is preferably a 3D laser profilometer, mainly used to detect whether the adhesive form is qualified after application. The vision positioning mechanism 7 includes an industrial camera, a light source, and an image processing module. The industrial camera uses a CCD or CMOS with more than 5 megapixels, and the lens is a telecentric lens or a fixed-focus lens with low distortion (<0.1%). The industrial camera is used to take pictures and capture images of the bottom surface of the battery module 9. The light source is set around the industrial camera to provide illumination, and the light source uses an adjustable brightness ring LED light source or a coaxial light source. The inspection instrument 6 and the vision positioning mechanism 7 are respectively set on the side of the two fourth tracks 45 opposite to the adhesive application head 5.

[0034] The control system 8 is the central scheduling and calculation core of the adhesive application device. It is electrically connected to the clamping mechanism 2, lifting drive mechanism 3, adhesive application drive mechanism 4, adhesive application head 5, detector 6, and vision positioning mechanism 7, realizing automated closed-loop control of the entire adhesive application process. The control system 8 includes: an industrial computer integrating data acquisition, control, and communication functions; an encoder that controls the clamping mechanism 2, lifting drive mechanism 3, and adhesive application drive mechanism 4; and an image processing module used to process images, generate the actual adhesive application contour, and plan the actual adhesive application path.

[0035] After the battery module 9 arrives from the previous process, the control system 8 controls the clamping mechanism 2 to grip the battery module 9 and rotate it 180°, flipping the bottom surface of the battery module 9 upwards. The control system 8 processes the image generated by the vision positioning mechanism 7 to generate the adhesive application area and plan the adhesive application trajectory. During adhesive application, the control system 8 controls the adhesive application drive mechanism 4 to move the adhesive application head 5 along the set adhesive application trajectory, performing continuous and uniform adhesive application in the adhesive application area on the bottom surface of the battery module 9. During the adhesive application process, the control system 8 also controls the lifting drive mechanism 3 to adjust the distance between the bottom surface of the battery module 9 and the adhesive application head 5 in real time based on the detection data of the distance sensor, keeping the two at a preset distance. The control system 8 also controls the output power of the adhesive pump and adjusts the adhesive flow rate based on the flow monitor. After adhesive application is completed, the detector 6 detects the adhesive type, and the control system 8 uses this to determine whether the adhesive application of the battery module 9 is qualified.

[0036] The battery module bottom surface adhesive application device replaces the existing method of applying adhesive to the liquid cooling plate 10 by applying adhesive to the bottom surface of the battery module 9. The adhesive application area accounts for 40%-70% of the bottom surface of the battery module 9. This reduction in application area reduces adhesive consumption by 50%-70%, preventing significant adhesive waste. Simultaneously, the reduced application area lowers the flatness requirements for the bottom surface of the battery module 9, resulting in a significantly better flatness and consistency compared to the brazed liquid cooling plate 10. This reduces defects such as insufficient adhesive or uneven adhesive layers caused by deformation of the liquid cooling plate 10, thus improving yield. After adhesive application, in-situ inspection is performed using the testing instrument 6 for timely assessment; any problems can be promptly addressed and repaired.

[0037] According to an embodiment of the present invention, in another aspect, a method for applying adhesive to the bottom surface of a battery module is also provided, which is applied to the bottom surface of a battery module 9 by a battery module bottom surface adhesive application device, comprising: S1: The battery module bottom adhesive applicator clamps the battery module 9 and flips it so that the bottom of the battery module 9 faces the upward adhesive applicator head 5. First, the lifting drive mechanism 3 controls the clamping mechanism 2 to descend to a suitable height. The specific process is as follows: the lifting drive component 33 is started, which drives the gear 34 to rotate. The gear 34 meshes with the rack 35, which can drive the connecting column 32 to move downward along the second track 36, and simultaneously drive the clamping mechanism 2 to descend, so that the battery module 9 is located between the two clamping plates 22 of the clamping mechanism 2.

[0038] Then, the clamping mechanism 2 clamps the battery module 9. Specifically, the clamping drive 23 controls the clamping plate 22 to move, so that the distance between the two clamping plates 22 is reduced until the two rotating seats 26 abut against the two ends of the battery module 9 respectively.

[0039] Afterwards, the lifting drive mechanism 3 controls the clamping mechanism 2 to rise to a suitable height, and then the flipping drive component 24 in the clamping mechanism 2 drives the entire battery module 9 to rotate 180°, so that the bottom surface of the battery module 9 faces upward and is directly facing the glue applicator 5.

[0040] S2: Obtain an image of the bottom surface of battery module 9, generate the actual adhesive application area and plan the actual adhesive application trajectory; The visual positioning mechanism 7 can capture an image of the bottom surface of the battery module 9, which is then processed by the control system 8 to determine the actual adhesive application area and plan the adhesive application path of the adhesive application head 5. Specifically, this includes the following steps: The S21 captures an image of the bottom surface of battery module 9; Specifically, the system uses a light source for illumination, and an industrial camera takes a picture of the bottom surface of the battery module 9 to obtain an image of the bottom surface of the battery module 9. The image is then transmitted to the control system 8 for subsequent analysis and processing.

[0041] Furthermore, when the battery module 9 is large enough that a single photograph cannot cover the entire bottom surface of the battery module 9, the bottom surface of the battery module 9 can be divided into multiple areas. By taking multiple photographs, multiple images are generated and stitched together to finally obtain a complete image of the bottom surface of the battery module 9. During this process, the shooting position can be changed by the adhesive application drive mechanism 4.

[0042] S22 preprocesses the image; The main process involves analyzing and processing the images through the control system 8 to facilitate the subsequent determination of the adhesive application area. This includes the following steps: Convert the image to grayscale, transforming it into a black and white image; The images captured by the industrial camera are color images containing red, green, and blue colors, resulting in a large data volume and offering no benefit for edge recognition of the battery module 9. Therefore, the control system 8 converts the color images into black and white images, preserving brightness information while reducing data volume and improving processing speed.

[0043] Denoising the image to eliminate noise; Images captured by industrial cameras may contain noise caused by changes in ambient light, camera noise, or minor scratches on the surface of the battery module 9. The control system 8 uses a filtering algorithm to smooth the image, eliminating these noise points and making the edges of the battery module 9 in the image clearer and more continuous.

[0044] Enhance the contrast between the battery module 9 area and the background in the image; Typically, the bottom surface of the battery module 9 is made of metal, and the difference in brightness between it and the background is not obvious. The control system 8 uses an enhancement algorithm to adjust the brightness distribution of the image, making the contrast between the edges of the battery module 9 and the background more prominent, which facilitates subsequent edge recognition.

[0045] The image is binarized and converted into a black and white binary image.

[0046] The control system 8 converts the processed image into a black and white binary image, in which the area of ​​the battery module 9 is displayed in white and the background area is displayed in black, forming a clear outline image.

[0047] S23 obtains the actual outline of battery module 9 based on the preprocessed image; Specifically, it includes the following steps: Detect the image after binarization; The control system 8 will perform edge detection on the binarized contour image and extract the contour features of the bottom surface of the battery module 9, mainly including the position information of the four sides and four corners of the bottom surface of the battery module 9.

[0048] Based on the brightness difference between each pixel in the image and its surrounding pixels, pixels with drastic brightness changes are identified as edge points; The image scans each pixel in the contour image and calculates the brightness difference between each pixel and its surrounding pixels. Since the area of ​​the battery module 9 is displayed as white and the background area is displayed as black, the brightness changes drastically. Pixels with large brightness differences can be identified as edge points.

[0049] Connect all edge points to obtain the actual outline of battery module 9.

[0050] Connecting all the edge points sequentially forms the actual outline of battery module 9.

[0051] S24 generates the actual adhesive application area based on the actual contour and preset process parameters; The preset process parameters are the safety distance between the actual adhesive application area and the actual contour. The preset process parameters are stored in the control system 8 in the form of a formula. Different sizes and specifications of battery modules 9 correspond to different formulas. The control system 8 automatically calls the corresponding formula to achieve rapid model changeover.

[0052] The safety distance can be selected as 2-5mm. In this embodiment, the actual adhesive application area is 3mm from the front edge, 3mm from the rear edge, 3mm from the left edge, and 3mm from the right edge of the battery module 9. The control system 8 moves each edge of the actual contour of the bottom surface of the battery module 9 inward by the above-mentioned safety distance, and the enclosed area formed is the actual adhesive application area.

[0053] Furthermore, when there are depressions, protrusions, or areas that need to be avoided on the bottom surface of the battery module 9 (such as the tab connection, sampling line interface, etc.), the control system 8 can adjust the adhesive application area according to the preset avoidance rules and remove areas that are not suitable for adhesive application.

[0054] S25 calculates the deviation data by comparing the actual profile with the theoretical profile; The control system 8 stores multiple theoretical contours of the bottom surfaces of battery modules 9 of different sizes. Based on the comparison between the actual contour and the theoretical contour, deviation data is calculated. The deviation data includes displacement deviation value and angle deviation value. The displacement deviation value refers to the displacement offset between a certain point of the actual contour and the corresponding point of the theoretical contour, while the angle deviation refers to the rotation angle offset of the actual contour relative to the theoretical contour.

[0055] Specifically, it includes the following steps: The corner points of the actual contour are used as the first reference point, and the corner points of the theoretical contour are used as the second reference point. The positions of the corresponding first reference point and second reference point are compared to obtain the displacement deviation value of the actual contour relative to the theoretical contour on the reference plane. The reference plane is the plane containing the length and width directions of the battery module 9. The reference plane is a plane parallel to the bottom surface of the battery module 9, where the direction parallel to the length of the battery module 9 is the X direction, and the direction parallel to the width of the battery module 9 is the Y direction.

[0056] The actual contour has four corner points, meaning there are at most four first reference points. During calculation, one or more of these first reference points can be selected. Selecting multiple first reference points to calculate multiple deviation values ​​can be achieved through averaging or least-squares fitting, reducing the impact of identification errors from individual first reference points on overall positioning accuracy. In other words, the more first reference points selected, the more accurate the calculation. The four corner points of the theoretical contour correspond one-to-one with the four corner points of the actual contour. The number of selected second reference points is equal to the number of first reference points, and their positions correspond accordingly.

[0057] For example, two first reference points located diagonally opposite each other on the actual contour are selected, and two second reference points located diagonally opposite each other on the theoretical contour are selected. The coordinates of the two first reference points on the reference plane are (X1, Y1) and (X2, Y2), respectively, and the coordinates of the two second reference points on the reference plane are (x1, y1) and (x2, y2), respectively. The displacement offset of the actual contour relative to the theoretical contour on the reference plane can be calculated based on the coordinates.

[0058] The line connecting any two diagonal corner points on the actual contour is taken as the first reference line, and the line connecting any two diagonal corner points on the theoretical contour is taken as the second reference line. The angle difference between the first reference line and the second reference line is calculated to obtain the rotational deviation value of the actual contour relative to the theoretical contour on the reference plane.

[0059] For example, select two first reference points located diagonally on the actual contour, connect the two first reference points to obtain the first reference line, select two second reference points located diagonally on the theoretical contour, connect the two second reference points to obtain the second reference line, and calculate the angle difference between the first reference line and the second reference line to obtain the rotation deviation value.

[0060] S26 generates the actual adhesive application trajectory based on the adhesive application pattern and deviation data.

[0061] There are three glue application modes: rectangular spiral mode, parallel line mode, and serpentine mode. You can choose one of them to apply glue according to your needs.

[0062] Rectangular spiral pattern: Starting from the center of the adhesive coating area, the coating expands outwards in rectangular rings until it covers the entire coating area. This method is suitable for scenarios where the entire bottom surface of the battery module 9 needs to be uniformly coated.

[0063] Parallel line pattern: This mode generates multiple parallel straight adhesive application paths along the long side of the adhesive application area with a set spacing. It is suitable for scenarios with specific requirements on the adhesive application direction, such as aligning the adhesive lines with the coolant flow direction.

[0064] Snake line pattern: Starting from one corner of the adhesive application area, the process proceeds back and forth along the long side until the entire area is covered. This method balances adhesive application efficiency and coverage uniformity, making it the most commonly used method in industrial applications.

[0065] For battery modules 9 of different sizes, each coating mode has a theoretical coating area and a theoretical coating path. Based on the deviation data between the actual contour and the theoretical contour, the actual coating trajectory can be corrected. For example, if the length direction of the battery module 9 is defined as the left-right direction and the width direction as the front-back direction, if the actual contour is offset to the left by ΔX compared to the theoretical contour, the actual coating trajectory will also be offset to the left by ΔX compared to the theoretical coating trajectory; if the actual contour is offset forward by ΔY compared to the theoretical contour, the actual coating trajectory will also be offset to the left by ΔY compared to the theoretical coating trajectory. If the actual contour is rotated by an angle θ compared to the theoretical contour, the actual coating trajectory will also be rotated by an angle θ compared to the theoretical coating trajectory.

[0066] Preset glue application parameters can be quickly switched. Simply changing the corresponding glue application nozzle can adapt to the glue application needs of various module sizes, reducing changeover time from hours to minutes.

[0067] S3: The glue applicator 5 applies glue to the bottom surface of the battery module 9 according to the actual glue application trajectory; The glue application drive mechanism 4 controls the movement of the glue application head 5, applying glue from the starting position of the actual glue application trajectory according to the corrected actual glue application trajectory. The coverage area of ​​the glue application trajectory is 40%-70% of the bottom surface area of ​​the battery module 9. The glue is delivered from the glue tank to the glue application head 5 through the glue pump and glue tube. During the glue application process, the distance sensor detects the distance between the glue nozzle of the glue application head 5 and the bottom surface of the battery module 9 in real time, and the height of the battery module 9 is dynamically adjusted by the lifting drive mechanism 3 to keep the distance between the glue nozzle of the glue application head 5 and the bottom surface of the battery module 9 at a preset distance.

[0068] Furthermore, the glue flow rate also needs to be dynamically adjusted. The target glue line cross-sectional area is set as S0, and the current glue application speed is v. Then the target glue flow rate Q = S0·v·k, where k is the compression coefficient, which takes a value of 1.1-1.3. The flow monitor provides real-time feedback on the actual glue flow rate, and the control system 8 adjusts the speed of the glue supply pump through the PID algorithm to make the actual glue flow rate approach the target value.

[0069] S4: Inspect the adhesive pattern on the bottom surface of battery module 9; The detector 6 moves along the adhesive application trajectory to scan the cross-sectional profile of the adhesive line. Obtain data on glue height, glue width, and glue path continuity based on the scanning results; The acquired data is compared with preset standards.

[0070] Specifically, after the adhesive is applied, the adhesive application drive mechanism 4 drives the detector 6 (3D laser profilometer) to move along the length of the battery module 9, scanning the cross-sectional profile of the adhesive line. It acquires data on adhesive height, width, and continuity of the adhesive path. The control system 8 compares the detection data from the detector 6 with preset standards to determine whether the adhesive application quality is qualified. The qualified standards for adhesive type detection are: adhesive height within the range of 0.2mm-0.8mm, adhesive width deviation not exceeding ±0.3mm, continuous adhesive line without breaks, and the cross-sectional shape of the adhesive line meeting preset requirements.

[0071] The adhesive application height is adjusted in real time by a distance sensor, the actual adhesive flow rate is fed back in real time by a flow meter unit, and the adhesive pattern is detected online by a 3D laser profilometer, forming a complete quality closed loop to ensure adhesive application accuracy and consistency.

[0072] Moreover, the precise application of adhesive to the bottom of the battery module 9 makes the adhesive layer thickness more uniform and controllable, avoiding the problem of excessive local adhesive layer caused by deformation of the liquid cooling plate 10 in traditional large-area adhesive application. This can effectively reduce thermal resistance and improve heat dissipation efficiency by about 10%-15%.

[0073] S5: If the inspection is qualified, flip the battery module 9 so that its bottom surface faces away from the glue applicator 5 and place it on the liquid cooling plate 10, and then transfer it to the pressing process with the liquid cooling plate 10. If the test fails, battery module 9 will be marked and await repair.

[0074] If the adhesive conformation test is qualified, the battery module 9 is rotated 180° by the clamping mechanism 2 so that the bottom surface of the battery module 9 is facing down again. Then the lifting drive mechanism 3 drives the battery module 9 to descend and place it on the liquid cooling plate 10 below. After that, it is transferred to the next process to press the battery module 9 and the liquid cooling plate 10 together.

[0075] If the glue type fails the inspection, the control system 8 issues an alarm signal and records the defect type and location information to the production management system. The battery module 9 is then marked as a product to be returned for repair and awaits on-site repair.

[0076] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for applying adhesive to the bottom surface of a battery module, used in a battery module bottom surface adhesive application device to apply adhesive to the bottom surface of a battery module (9), characterized in that, include: The bottom adhesive applicator of the battery module clamps the battery module (9) and flips it so that the bottom surface of the battery module (9) faces the top adhesive applicator (5). Obtain an image of the bottom surface of the battery module (9), generate the actual adhesive application area, and plan the actual adhesive application trajectory; The glue applicator (5) applies glue to the bottom surface of the battery module (9) according to the actual glue application trajectory; The adhesive pattern on the bottom surface of the battery module (9) is inspected; If the test is qualified, the battery module (9) is flipped over so that its bottom surface faces away from the glue applicator (5) and placed on the liquid cooling plate (10), and then transferred to the pressing process with the liquid cooling plate (10); If the test fails, the battery module (9) will be marked and await repair.

2. The method for applying adhesive to the bottom surface of a battery module according to claim 1, characterized in that, The steps of acquiring an image of the bottom surface of the battery module (9), generating the actual adhesive application area, and planning the actual adhesive application trajectory include: Take a picture to capture an image of the bottom surface of the battery module (9); The image is preprocessed; The actual outline of the battery module (9) is obtained from the preprocessed image; The actual adhesive application area is generated based on the actual contour and preset process parameters; The deviation data is calculated by comparing the actual contour with the theoretical contour. The actual adhesive application trajectory is generated based on the adhesive application pattern and the deviation data.

3. The method for applying adhesive to the bottom surface of a battery module according to claim 2, characterized in that, The step of preprocessing the image includes: Convert the image to grayscale, transforming it into a black and white image; Denoising the image to eliminate noise; Enhance the contrast between the battery module (9) area and the background in the image; The image is binarized and converted into a black and white binary image.

4. The method for applying adhesive to the bottom surface of a battery module according to claim 3, characterized in that, The step of obtaining the actual contour of the battery module (9) based on the preprocessed image includes: Detect the image after binarization; Based on the brightness difference between each pixel in the image and its surrounding pixels, pixels with drastic brightness changes are identified as edge points; Connect all edge points to obtain the actual outline of the battery module (9).

5. The method for applying adhesive to the bottom surface of a battery module according to claim 2, characterized in that, The step of calculating the deviation data based on the comparison between the actual contour and the theoretical contour includes: The corner points of the actual contour are used as the first reference point, and the corner points of the theoretical contour are used as the second reference point. The positions of the corresponding first reference point and second reference point are compared to obtain the displacement deviation value of the actual contour compared with the theoretical contour on the reference plane. The reference plane is the plane where the length direction and width direction of the battery module (9) are located. The line connecting any two diagonal corner points on the actual contour is taken as the first reference line, and the line connecting any two diagonal corner points on the theoretical contour is taken as the second reference line. The angle difference between the first reference line and the second reference line is calculated to obtain the rotational deviation value of the actual contour relative to the theoretical contour on the reference plane.

6. The method for applying adhesive to the bottom surface of a battery module according to claim 5, characterized in that, In the step of generating the actual adhesive application area based on the actual contour and preset process parameters, the preset process parameters are the safety distance between the actual adhesive application area and the actual contour.

7. The method for applying adhesive to the bottom surface of a battery module according to claim 2, characterized in that, In the step of generating the actual adhesive application trajectory based on the adhesive application pattern and the deviation data, the adhesive application pattern is a rectangular spiral pattern, a parallel line pattern, or a serpentine line pattern.

8. The method for applying adhesive to the bottom surface of a battery module according to claim 1, characterized in that, In the step of applying glue to the bottom surface of the battery module (9) by the glue applicator (5) according to the actual glue application trajectory, the distance between the glue nozzle of the glue applicator (5) and the bottom surface of the battery module (9) is maintained at a preset distance.

9. The method for applying adhesive to the bottom surface of a battery module according to claim 1, characterized in that, The step of detecting the adhesive pattern on the bottom surface of the battery module (9) includes: The detector (6) moves along the adhesive application trajectory to scan the cross-sectional profile of the adhesive line; Obtain data on glue height, glue width, and glue path continuity based on the scanning results; The acquired data is compared with preset standards.

10. A battery module bottom surface adhesive coating apparatus, employing the adhesive coating method according to any one of claims 1-9, characterized in that, include: Body (1); A clamping mechanism (2) is provided on the body (1) for clamping and flipping the battery module (9). A lifting drive mechanism (3) is provided on the body (1), and its drive end is connected to the clamping mechanism (2), which is suitable for driving the clamping mechanism (2) to move along the height direction of the battery module (9); A glue application drive mechanism (4) is mounted on the body (1); The glue applicator (5) is connected to the drive end of the glue applicator drive mechanism (4) and is located above the battery module (9); The detector (6) is connected to the drive end of the glue application drive mechanism (4); The visual positioning mechanism (7) is connected to the drive end of the glue application driving mechanism (4); The adhesive application driving mechanism (4) is adapted to drive the adhesive application head (5), the detector (6) and the vision positioning mechanism (7) to move along the length and width directions of the battery module (9); The control system (8) is electrically connected to the clamping mechanism (2), the lifting drive mechanism (3), the glue application drive mechanism (4), the glue application head (5), the detector (6), and the visual positioning mechanism (7).

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