A battery welding method

Abstract

This invention relates to a battery welding method, belonging to the field of battery technology. The battery welding method includes: obtaining the original coordinates of all terminals and feature points in a first coordinate system at the pre-welding station based on the battery identification code; then determining the relative coordinates of the terminal to be repaired relative to the feature points based on the obtained reference coordinates of the feature points in a second coordinate system at the welding station; obtaining a set of relative coordinates of the terminals to be repaired corresponding to the same battery model in a database to calculate the reference coordinates and coordinate reliability index of the terminal to be repaired; if the coordinate reliability index meets preset requirements, the reference coordinates are used as the point coordinates; otherwise, the difference between the reference coordinates and the correction displacement is used as the point coordinates; the correction displacement is an empirical value; and determining the repair welding coordinates and performing repair welding based on the point coordinates and relative coordinates. This invention reduces the complexity of repair welding operations, decreases the scrap rate of off-center welding, and improves the efficiency of cell terminal repair welding while ensuring high-precision repair welding.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more specifically to a battery welding method. Background Technology

[0002] A battery typically comprises multiple cells, each consisting of a casing and an electrode assembly located inside the casing. The casing of each cell has terminals, and the cells are electrically connected via terminals and electrodes. The welding quality of the terminals and electrodes directly determines the battery's electrical and safety performance. Unlike the initial welding of terminals and electrodes under normal circumstances, when re-welding the terminals and electrodes of a cell is required, the cell surface is already covered by a CCS (Cells Contact System). The terminals are covered by the CCS electrodes. Due to the obstruction of the electrodes, the welding equipment cannot perform feature recognition on the terminals before welding, and therefore cannot obtain accurate terminal coordinates. If the original welding data is directly retrieved for welding under these circumstances, it may result in misalignment during welding, leading to product scrap.

[0003] To address the aforementioned welding repair issues, a two-stage welding solution has been proposed: the first welding operation uses low power to determine the welding position; the second welding operation uses high power to complete the repair.

[0004] However, the above-mentioned welding repair method requires two welding operations, which is not only complicated but also time-consuming and inefficient. Summary of the Invention

[0005] This invention provides a battery welding method that can reduce the complexity of repair welding operations and improve the automation level and efficiency of repair welding of cell terminals and plates.

[0006] This invention provides a battery welding method, the method comprising: Based on the battery identification code, the original coordinates of all terminals and feature points in the first coordinate system of the pre-welding station are obtained. Then, based on the reference coordinates of the feature points in the second coordinate system of the welding station, the relative coordinates of the terminal to be repaired relative to the feature points are determined. Obtain the set of relative coordinates of the corresponding terminals to be repaired for the same type of battery in the database, in order to calculate the reference coordinates and coordinate reliability index of the terminals to be repaired; If the above coordinate reliability index meets the preset requirements, then the above reference coordinates are used as the point coordinates; otherwise, the difference between the above reference coordinates and the corrected displacement is used as the point coordinates; the above corrected displacement is an empirical value. Based on the above point coordinates and relative coordinates, determine the coordinates for the repair welding and perform the repair welding.

[0007] In one implementation, before obtaining the set of relative coordinates of the corresponding terminals to be repaired for the same type of battery in the database, the method further includes: When welding the terminals of any battery, at the pre-welding station, the original coordinates of all terminals and two feature points of the battery in the first coordinate system are obtained, and at the welding station, the reference coordinates of the two feature points in the second coordinate system are obtained. Based on the reference coordinates of the two feature points mentioned above, and the original coordinates of all poles and the two feature points, any one of the two feature points is selected as the reference feature point, and the relative coordinates of all poles relative to the reference feature point in the second coordinate system are calculated; and the reference feature points of all batteries of the same model correspond to the same feature point. Establish a mapping relationship between the battery identification code and the relative coordinates, and store the mapping relationship in a database; wherein, the relative coordinates of the terminals to be repaired for the same battery in the database constitute the set of relative coordinates.

[0008] In one implementation, the welding repair coordinates are determined and welding repair is performed based on the aforementioned point coordinates and relative coordinates, specifically including: The difference between the above point coordinates and the relative coordinates is taken as the positional deviation; Obtain the relative position of the camera and the galvanometer, and add the aforementioned positional deviation to the aforementioned relative position to obtain the target displacement; After moving the welding device from the position of the electrode to be repaired to the above-mentioned repair welding coordinates according to the above-mentioned target displacement, the repair welding is performed.

[0009] In one implementation, obtaining the relative position of the camera and the galvanometer specifically includes: When repairing the pole, mark a point within the welding station, move the welding device to place the mark point in the center of the camera's field of view, and use the current coordinates of the welding device as the first coordinate; Turn on the zero-position red light preview of the galvanometer and move the welding device so that the above-mentioned marked point coincides with the red light, and use the current coordinates of the welding device as the second coordinate; The difference between the second coordinate and the first coordinate is used as the relative position of the camera and the galvanometer.

[0010] In one implementation, calculating the reference coordinates of the electrode post to be repaired specifically includes: Obtain the quartiles of each dimension coordinate in the above relative coordinate set, and extract the concentrated region; Calculate the average value of the coordinates in this dimension for each concentrated region, and use it as the reference coordinate.

[0011] In one implementation, the coordinate reliability index includes coordinate confidence; calculating the coordinate reliability index specifically includes: Based on the above set of relative coordinates, calculate the data volume, proportion, and standard deviation of the concentrated region; The data volume score is obtained based on the above data volume, the concentration score is determined based on the above proportion, and the standard deviation score is obtained based on the above standard deviation. Based on the above data volume score, concentration score, and standard deviation score, the coordinate confidence score is obtained.

[0012] In one implementation, the formula for calculating the coordinate confidence level C is as follows: C = D × (λ1S + λ2I) Where D is the data volume score, S is the concentration score, I is the standard deviation score, λ1 is the weighting coefficient of the concentration score, and λ2 is the weighting coefficient of the standard deviation score.

[0013] In one implementation, the method further includes obtaining the coordinate confidence score before: Calculate the excess kurtosis based on the above set of relative coordinates; The weighting coefficients for the concentration score and the standard deviation score are determined based on the aforementioned excess kurtosis. The larger the excess kurtosis, the larger the weighting coefficient for the concentration score.

[0014] In one embodiment, the coordinate reliability index further includes a coefficient of variation; the calculation of the coordinate reliability index also includes: Calculate the coefficient of variation based on the standard deviation and reference coordinates mentioned above; If the above coefficient of variation is less than the preset coefficient, then the above coefficient of variation is judged to meet the preset requirements.

[0015] In one embodiment, two feature points are included. Based on the reference coordinates of the feature points in the second coordinate system of the welding station, the relative coordinates of the electrode post to be repaired relative to the feature points are determined. Specifically, this includes: Two feature points are photographed at the welding station to obtain the reference coordinates of the feature points in the second coordinate system of the welding station. Choose either of the two feature points as the reference feature point. Based on the reference coordinates of the two feature points, and the original coordinates of all poles and the two feature points, calculate the relative coordinates of all poles relative to the reference feature point in the second coordinate system, and select the relative coordinates of the pole to be repaired from them; or, choose either of the two feature points as the reference feature point. Based on the reference coordinates of the two feature points, and the original coordinates of the two feature points, and select the original coordinates of the pole to be repaired, calculate the relative coordinates of the pole to be repaired relative to the reference feature point in the second coordinate system.

[0016] The beneficial effects of the technical solutions provided by the embodiments of the present invention include: By directly acquiring the coordinates of feature points at the welding station to obtain the relative coordinates of the electrode to be repaired, and by using statistical analysis of historical data to adaptively determine the reference coordinates, the data quality is quantified through coordinate reliability indicators to eliminate system errors, thereby obtaining the repair coordinates for repair welding. This ensures high-precision repair welding while reducing the complexity of the repair welding operation, reducing the scrap rate of off-center welding, and improving the automation level and efficiency of repair welding of battery cell electrodes and foils. It solves the technical problems of complex, time-consuming, and inefficient repair welding operations in related technologies. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart of an embodiment of the battery welding method of the present invention; Figure 2 This is a schematic diagram showing the relative positions of the camera and the galvanometer in an embodiment of the present invention; Figure 3 This is a schematic flowchart illustrating another embodiment of the welding method for the battery of the present invention.

[0019] In the diagram: 1. Camera mechanism; 2. Galvanometer mechanism; 3. Air knife mechanism; 4. External tooling; 5. Robot body. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and 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.

[0021] This invention provides a battery welding method that solves the technical problems of complex, time-consuming, and inefficient repair welding operations in related technologies.

[0022] like Figure 1 As shown, the battery welding method in this embodiment includes the following steps: S1. Based on the battery identification code, obtain the original coordinates of all terminals and feature points in the first coordinate system of the pre-welding station, and then determine the relative coordinates of the terminal to be repaired relative to the feature points according to the reference coordinates of the feature points in the second coordinate system of the welding station. S2. Obtain the set of relative coordinates of the corresponding terminals to be repaired for the same type of battery in the database, so as to calculate the reference coordinates and coordinate reliability index of the terminals to be repaired; S3. If the above coordinate reliability index meets the preset requirements, then the above reference coordinates shall be used as the point coordinates; otherwise, the difference between the above reference coordinates and the corrected displacement shall be used as the point coordinates; the above corrected displacement is an empirical value. S4. Based on the above point coordinates and relative coordinates, determine the welding coordinates and perform the welding repair.

[0023] In this embodiment, the original coordinates of all terminals and feature points in the first coordinate system of the pre-welding station are obtained based on the battery identification code. Then, the relative coordinates of the terminal to be repaired relative to the feature points are determined based on the obtained reference coordinates of the feature points in the second coordinate system of the welding station. The set of relative coordinates of the terminal to be repaired corresponding to the same battery as the battery mentioned above is obtained from the database to calculate the reference coordinates and coordinate reliability index of the terminal to be repaired. If the coordinate reliability index meets the preset requirements, the reference coordinates are used as the point coordinates; otherwise, that is, if the coordinate reliability index does not meet the preset requirements, the difference between the reference coordinates and the correction displacement is used as the point coordinates. The correction displacement is an empirical value. Based on the point coordinates and relative coordinates, the repair welding coordinates are determined and repair welding is performed.

[0024] By directly acquiring the coordinates of feature points at the welding station to obtain the relative coordinates of the electrode to be repaired, and by using statistical analysis of historical data to adaptively determine the reference coordinates, the data quality is quantified through coordinate reliability indicators to eliminate system errors, thereby obtaining the repair coordinates for repair welding. This ensures high-precision repair welding while reducing the complexity of the repair welding operation, reducing the scrap rate of off-center welding, and improving the automation level and efficiency of repair welding of battery cell electrodes and foils. It solves the technical problems of complex, time-consuming, and inefficient repair welding operations in related technologies.

[0025] It should be noted that the welding or repair welding of the electrode post in this application refers to the welding between the electrode post and the electrode plate, and whether it is repair welding or the first welding, it is all performed at the same welding station.

[0026] Based on the above embodiments, in this embodiment, before obtaining the set of relative coordinates of the corresponding terminals to be repaired for the same type of battery in the database in step S1, the method further includes: First, when welding the terminals of any battery, at the pre-welding station, the original coordinates of all terminals and two feature points of the battery in the first coordinate system are obtained. Then, at the welding station, the reference coordinates of the two feature points in the second coordinate system are obtained. Secondly, based on the reference coordinates of the two feature points mentioned above, and the original coordinates of all poles and the two feature points, any one of the two feature points is selected as the reference feature point, and the relative coordinates of all poles relative to the reference feature point in the second coordinate system are calculated; and the reference feature points of all batteries of the same model correspond to the same feature point. Finally, a mapping relationship between the battery identification code and the relative coordinates is established, and the mapping relationship is stored in the database; wherein, the relative coordinates of the terminals to be repaired for the same battery in the database constitute the set of relative coordinates.

[0027] It should be noted that the welding of the terminals can be either the initial welding or a repair welding process. If it is a repair welding process, the data from the initial welding is overwritten, and a mapping relationship is established between the battery identification code and the newly determined relative coordinates. Furthermore, "all reference feature points of the same battery model correspond to the same feature point" means that, for example, if two feature points are feature point one and feature point two, then for the same battery model, feature point one can be selected as the reference feature point for all batteries, or feature point two can be selected as the reference feature point for all batteries, rather than selecting feature point one as the reference feature point for some batteries and feature point two as the reference feature point for others.

[0028] Furthermore, calculating the relative coordinates of all poles in the second coordinate system relative to the aforementioned reference feature point includes: calculating the absolute coordinates of all poles in the second coordinate system, and calculating the relative coordinates of all poles relative to the aforementioned reference feature point based on the absolute coordinates and the reference coordinates of the aforementioned reference feature point.

[0029] In this embodiment, by storing the reference coordinates of the battery's feature points in the second coordinate system and calculating the relative coordinates of all poles relative to the feature points, a mapping relationship between the battery identification code and the pole relative coordinates can be established. This mapping relationship is then stored to obtain the aforementioned database, providing pole coordinate references for the soldering process and solving the technical problem of pole coordinates being unrecognizable due to CCS foil coverage. Furthermore, the battery identification code can not only have a mapping relationship with the relative feature points, but also with the original coordinates of the poles and feature points, as well as the reference coordinates of the feature points. The battery identification code typically also contains information such as the battery model. By establishing the mapping relationship between the battery identification code and the relative coordinates, the relative coordinates corresponding to the same battery model in the database can be aggregated to form a set of relative coordinates.

[0030] Furthermore, in one embodiment, step S4 above, determining the welding coordinates and performing welding based on the aforementioned point coordinates and relative coordinates, specifically includes: First, the difference between the above point coordinates and the relative coordinates is taken as the positional deviation; Then, the relative position of the camera and the galvanometer is obtained, and the above positional deviation is added to the above relative position to obtain the target displacement; Finally, the welding device is moved from the position of the electrode to be repaired to the repair welding coordinates according to the target displacement, and then the repair welding is performed. Here, the position of the electrode to be repaired refers to its absolute coordinates in the second coordinate system. The welding device uses these coordinates as the starting coordinates for movement and is calibrated according to the target displacement. For example, the welding device can be a robot.

[0031] In this embodiment, by accurately calculating the positional deviation between the point and the pole relative to the coordinates, and combining the fixed relative position of the camera and the galvanometer, the precise calculation of the welding coordinates is achieved, effectively eliminating systematic and random errors, avoiding the cumbersome steps of low-power testing required in traditional welding methods, and significantly improving the welding efficiency and accuracy.

[0032] Furthermore, in one embodiment, the acquisition of the relative position of the camera and the galvanometer specifically includes: First, during pole repair welding, mark a point within the welding station, move the welding device to place the mark point in the center of the camera's field of view, and use the current welding device coordinates as the first coordinate; Then, turn on the zero-position red light preview of the galvanometer and move the welding device so that the above-mentioned marked point coincides with the red light, and use the current coordinates of the welding device as the second coordinate.

[0033] Finally, the difference between the second coordinate and the first coordinate is calculated as the relative position of the camera and the galvanometer.

[0034] Understandably, if the electrode post is welded correctly, no additional welding is required; if additional welding is needed, it should be done at the welding station.

[0035] Optionally, the aforementioned marker point can be any feature point within the workstation. For example, drawing a cross at a certain location within the workstation will serve as the marker point, facilitating accurate measurement of the relative positional relationship between the center point of the galvanometer and the center point of the camera.

[0036] In this embodiment, by accurately calibrating the relative positions of the camera and the galvanometer within the welding station, that is, by using a mobile robot to place the marked point in the center of the camera's field of view and align it with the red light of the galvanometer, the relative position is obtained by calculating the difference between the two coordinates. This effectively eliminates the inherent error of the system, provides a high-precision benchmark for subsequent coordinate calculations, ensures the accuracy of the welding position, and avoids welding offset caused by the deviation of the relative positions of the camera and the galvanometer.

[0037] In one specific embodiment, such as Figure 2 As shown, in this embodiment, the calibration of the relative positional relationship between the camera and the galvanometer specifically includes: First, mark point 1 within the welding station, move the robot so that mark point 1 is in the center of the camera's field of view, and record the robot's current coordinates as the first coordinate (X1, Y1). Then, turn on the zero-position red light preview of the galvanometer, move the robot so that the marker point 1 coincides with the red light, and record the robot's current coordinates as the second coordinate (X2, Y2). Finally, subtracting the value of the second coordinate from the value of the first coordinate yields the relative relationship between the two (△X1, △Y1).

[0038] In this embodiment, the camera mechanism 1, the galvanometer mechanism 2, and the air knife mechanism 3 are fixed to the external fixture 4 by screws, and their relative positions are fixed; the external fixture 4 is fixed to the robot body 5 by a flange mechanism.

[0039] Furthermore, in one embodiment, step S2 above, calculating the reference coordinates of the electrode post to be repaired, specifically includes: First, obtain the quartiles of each dimension coordinate in the above relative coordinate set, and extract the concentrated region; Then, the average value of the coordinates in that dimension is calculated for each concentrated region and used as the reference coordinates.

[0040] In this embodiment, by obtaining the quartiles of the X-dimensional coordinates and Y-dimensional coordinates in the relative coordinate set and extracting the concentrated regions, and then calculating the average value of the coordinates in each concentrated region, the reference coordinates are obtained. This achieves adaptive reference coordinate determination based on historical data and effectively eliminates system errors.

[0041] Further, in one embodiment, in step S2 above, the coordinate reliability index includes coordinate confidence; calculating the coordinate reliability index specifically includes: Based on the above set of relative coordinates, calculate the data volume, proportion, and standard deviation of the concentrated region; The data volume score is obtained based on the above data volume, the concentration score is determined based on the above proportion, and the standard deviation score is obtained based on the above standard deviation. Based on the above data volume score, concentration score, and standard deviation score, the coordinate confidence score is obtained.

[0042] Optionally, if the confidence level of the coordinates is greater than or equal to a preset confidence level, then the confidence level of the coordinates is determined to meet the preset requirement. Preferably, the preset confidence level is 90%.

[0043] In this embodiment, the coordinate reliability index, including data volume, proportion and standard deviation, is calculated by statistical analysis based on the relative coordinate set. The coordinate confidence is calculated by weighted formula, thereby realizing an objective quantitative assessment of data quality and effectively eliminating the uncertainty of relying entirely on human experience in traditional methods.

[0044] Furthermore, in this embodiment, the formula for calculating the coordinate confidence level C is as follows: C = D × (λ1S + λ2I).

[0045] Where D is the data volume score, S is the concentration score, I is the standard deviation score, λ1 is the weighting coefficient of the concentration score, and λ2 is the weighting coefficient of the standard deviation score.

[0046] Preferably, if the data volume in the aforementioned centralized area is greater than or equal to the standard data volume, then the data volume score D is 1; if the data volume in the aforementioned centralized area is less than the standard data volume, then the data volume score D is the ratio of the data volume to the standard data volume. The standard data volume is a standard value set according to actual needs.

[0047] Preferably, if the standard deviation δ of the aforementioned concentrated area is less than or equal to the standard value µ, then the standard deviation score I is 1; if the standard deviation δ of the aforementioned concentrated area is greater than the standard value, then the standard deviation score I = 1 / (1 + (δ - µ)). Wherein, the standard value µ is a value set according to actual needs.

[0048] Preferably, the concentration score S represents the proportion of the concentrated area.

[0049] Optionally, the weighting coefficients λ1 and λ2 of the concentration score and standard deviation score can be empirical values. In this embodiment, the coordinate confidence level C = D × (40%S + 60%I).

[0050] In other embodiments, the process further includes obtaining the coordinate confidence score before: First, calculate the excess kurtosis based on the aforementioned set of relative coordinates; Then, the weighting coefficients of the concentration score and the standard deviation score are determined based on the above excess kurtosis, and the larger the excess kurtosis, the larger the weighting coefficient of the concentration score.

[0051] In this embodiment, by calculating the excess kurtosis of the relative coordinate set and dynamically adjusting the weight coefficients of the concentration score and standard deviation score based on the excess kurtosis, the confidence calculation can adapt to the data distribution characteristics, significantly improving the accuracy of data quality assessment.

[0052] In this embodiment, the larger the excess kurtosis and the more concentrated the data distribution, the greater the weight coefficient of the concentration score and the smaller the weight coefficient of the standard deviation score. This makes the coordinate confidence calculation more fully reflect the concentration of the data, effectively avoids the evaluation bias caused by the fixed weight coefficient, and further improves the accuracy and reliability of the welding coordinate determination.

[0053] Optionally, a pre-set Map table of excess kurtosis and weighting coefficients can be consulted based on the excess kurtosis to obtain the weighting coefficients of the corresponding concentration score and standard deviation score.

[0054] Furthermore, in one embodiment, the coordinate reliability index further includes the coefficient of variation; the calculated coordinate reliability index also includes: Calculate the coefficient of variation based on the standard deviation and reference coordinates mentioned above. If the coefficient of variation is less than a preset coefficient, then the coefficient of variation is considered to meet the preset requirements.

[0055] In this embodiment, by introducing the coefficient of variation as a coordinate reliability index, the relative dispersion of the data is objectively quantified based on the calculation of the standard deviation and the reference coordinates. When the coefficient of variation is less than the preset coefficient, the data quality is determined to meet the reliability requirements, so as to overcome the limitation of relying solely on the absolute standard deviation to evaluate the data dispersion and to more accurately reflect the concentration of the data.

[0056] Preferably, the preset coefficient is 5%.

[0057] It is understandable that by obtaining the quartiles of the X and Y dimensions of the relative coordinate set separately, concentrated regions can be extracted. Accordingly, the coordinate confidence score and coefficient of variation are calculated and analyzed for each dimension. If the reliability index of any dimension does not meet the preset requirements, it indicates that the reference coordinates need to be manually verified.

[0058] Further, in one embodiment, step S1 above includes two feature points. After obtaining the original coordinates of all terminals and the two feature points in the first coordinate system of the pre-welding station based on the obtained battery identification code, the relative coordinates of the terminal to be repaired relative to the feature points are determined based on the obtained reference coordinates of the feature points in the second coordinate system of the welding station. Specifically, this includes: Two feature points are photographed at the welding station to obtain the reference coordinates of the two feature points in the second coordinate system of the welding station; specifically, a robot carrying a camera can be used to photograph two feature points at the welding station.

[0059] Choose either of the two feature points as the reference feature point. Based on the reference coordinates of the two feature points, and the original coordinates of all poles and the two feature points, calculate the relative coordinates of all poles relative to the reference feature point in the second coordinate system, and select the relative coordinates of the pole to be repaired from them; or, choose either of the two feature points as the reference feature point. Based on the reference coordinates of the two feature points, and the original coordinates of the two feature points, and select the original coordinates of the pole to be repaired, calculate the relative coordinates of the pole to be repaired relative to the reference feature point in the second coordinate system.

[0060] In one specific embodiment, the battery is a module, such as... Figure 3 As shown, the welding method for battery terminals at the welding station specifically includes: Step A1: Database Setup A101: During the initial welding of the pole posts, all modules are in the pre-welding station. A high-definition camera is used to obtain the coordinates of all pole posts and two feature points (Mark points) in the first coordinate system of the pre-welding station, which are used as the original coordinates. A102: At the welding station, a robot carrying a camera acquires the coordinates of two Mark points in the robot coordinate system (i.e., the second coordinate system) of this station, thereby calculating the absolute coordinates of all poles of the current module in the robot coordinate system (the calculation method includes translation and rotation). A103: Calculate the relative coordinates of each pole piece and a Mark point in the robot coordinate system to establish the mapping relationship between the module identification code (e.g., barcode) and the relative coordinates; A104: Store the identification codes and relative coordinates of all products, as well as the original coordinates of all poles and two Mark points, into the database. Welding can then be performed.

[0061] Step A2: Visual assistance to determine the offset position A201: Select the repair welding mode and use the scanning module identification code to retrieve the original coordinate data of the current module pole. That is, during the initial welding of the pole, all modules are in the pre-welding station, and the coordinates of all poles and two Mark points are obtained by using a high-definition camera. A202: At the welding station, the camera takes a picture of the Mark point. Based on the above original coordinate data, the relative coordinates of all poles of the module in the welding station during the repair welding are obtained. A203: Based on the relative coordinates, the robot, carrying the camera, moves to the selected location of the pole that needs to be repaired. A204: Obtain a visual image of the weld repair point; A205: The vision system performs adaptive analysis based on the standard coordinate model of the image and database; A206: The interface displays the information visually and outputs the reference coordinates, outline, and recommended point coordinates of the pole for welding repair, along with reliability index evaluation. A207: Determine whether the coordinate reliability index evaluation meets the preset requirements, that is, whether the coordinate confidence level is greater than or equal to 90% and whether the coefficient of variation is less than 5%; if yes, then directly confirm or correct manually, that is, go to A209; if no, then manually drag the contour, that is, go to A208.

[0062] A208: Manually drag the outline; A209: Perform manual confirmation or correction. Based on the evaluation of coordinate reliability index and the display of the weld repair outline, manual confirmation or confirmation after dragging the outline for fine adjustment is performed. The correction displacement for dragging the fine adjustment is the empirical value input by the operator. If the coordinate reliability index meets the preset requirements, the reference coordinates are used as the point coordinates. If there is a manual correction displacement, the difference between the reference coordinates and the correction displacement is used as the point coordinates. A210: Calculate the positional deviation (△X2, △Y2) between the point coordinates and the center point of the image (i.e., the relative coordinates of the pole to be welded), and send the deviation data to the controller (robot or PLC, etc.). A211: The controller executes the repair welding logic; A212: Update and overwrite the original product data information in the database based on the product identification code, and generate a log record; A213: Synchronously update the standard coordinate model.

[0063] During normal welding of the pole posts, product coordinate data in the database can be continuously supplemented and the standard coordinate model updated. Specifically, this includes: During normal welding, the robot takes a picture of the product's Mark point and performs coordinate transformation calculations to determine the relative coordinates of the pole piece; Then, welding is performed, and welding coordinates and welding data are recorded, including process data such as power and speed. Finally, the data is synchronized into the database, and the standard coordinate model is updated.

[0064] Furthermore, when the aforementioned controller executes the welding repair logic, it determines the robot's welding repair position, specifically including: First, obtain the relative coordinates (X3, Y3) of the welding repair electrode in the robot coordinate system within the welding station; Then, combining the relative coordinates (X3, Y3), the above position deviation values ​​(△X2, △Y2), and the relative relationship between the camera and the galvanometer (△X1, △Y1), the welding coordinates (X4, Y4) are obtained: X4 = X3 + △X1 + △X2, Y4 = Y3 + △Y1 + △Y2.

[0065] In this embodiment, the displacement that the robot needs to move from its relative coordinate position during the welding process can be calculated, which is the sum of the above position deviation values ​​(△X2, △Y2) and the relative relationship between the camera and the galvanometer (△X1, △Y1), so that the position of zero offset of the galvanometer coincides with the position that needs to be manually calibrated for welding.

[0066] In this embodiment, when calculating the above-mentioned reference coordinates, the statistical process control (SPC) principle and software algorithm can be used to collect data of each pole of all modules of the same type to form a database, and automatically learn and analyze the data of each pole. This is so that the coordinate reliability index and the recommended reference coordinates of each pole can be automatically output according to the analysis results. After welding or repair welding is completed, the coordinate data in the corresponding identification code is updated. That is, after each repair welding is completed, the repair welding coordinates can also be used as the relative coordinates of the pole of the module to update the database.

[0067] Specifically, taking a certain pole as an example, which has accumulated N sets of coordinate data, the coordinate data is analyzed based on the quantity and value of the coordinate data: First, quartiles are calculated to extract the concentrated regions of each dimension, and the average value of the data within the concentrated regions is used as the reference coordinate.

[0068] Secondly, calculate the standard deviation δ, coefficient of variation, excess kurtosis, and proportion of the concentrated region for each dimension. Specifically, the coefficient of variation (CV) = (δ / baseline coordinate of that dimension) * 100%, and the excess kurtosis is calculated to determine the degree of peaking in the distribution; the proportion of the concentrated region = (data volume of the concentrated region / total data volume) * 100%.

[0069] Then, calculate the scores: 1) Data volume score: Set a standard data volume. When the data volume is less than the standard data volume, the data volume score = data volume / standard data volume; when the data volume is greater than or equal to the standard data volume, the data volume score = 1.

[0070] 2) Standard deviation: When δ ≤ standard value µ, the standard deviation = 1; when δ > standard value µ, the standard deviation = 1 / (1+(δ-µ)).

[0071] 3) Concentration score: Concentration score = percentage of concentrated areas.

[0072] At this point, the confidence score can be quantified and output, i.e., the coordinate confidence score C = data volume score * (standard deviation score * λ2 + concentration score * λ1).

[0073] Optionally, the data concentration can be determined based on whether the excess kurtosis is greater than 0, and the weights λ1 and λ2 of the above scores can be adjusted accordingly. Specifically, the larger the excess kurtosis, the larger the weight coefficient λ1 of the concentration score.

[0074] Preferably, data quality can be judged in advance. That is, when the amount of data in the concentrated area is ≥100, if the standard deviation δ≤1mm, the above reference coordinates are high-quality coordinate data; if 1mm<δ<2mm, they are acceptable coordinate data; if δ>2mm, they are unqualified coordinate data.

[0075] Preferably, a validity judgment can be made in advance. That is, if the proportion of the concentrated area is >85% and δ≤1mm, the above reference coordinates are reliable data; if the proportion of the concentrated area is <70% or δ>2mm, the above reference coordinates are unreliable data.

[0076] In this embodiment, the confidence level is used to determine the reliability of the reference coordinates. If the confidence score is ≥90%, the reference coordinates are highly reliable; if the confidence score is 70% < 90%, the reference coordinates need to be confirmed; and if the confidence score is <70%, the reference coordinates are for reference only.

[0077] Furthermore, the coefficient of variation (CV) can be used for auxiliary verification. If CV < 5%, the relative dispersion is low, and the above reference coordinate data is valid. If CV ≥ 5%, the above reference coordinates are unreliable.

[0078] In this embodiment, the total number of data points is 200, the number of concentrated regions is 190 (accounting for 95%), the optimal value is 32.5, the standard deviation is 0.7, the CV is 2.15%, the range of the concentrated regions is (29.2-35.8), and the kurtosis is 0.8.

[0079] At this point, the visual interface for the weld repair displays the text: "High data quality, reliable data, good concentration, confidence score 98%." The reference coordinates can then be used directly as the point coordinates to determine the weld repair coordinates.

[0080] Optionally, in this embodiment, the interface element design includes the following when performing visual human-computer interaction: 1. Real-time image display: Real-time images of the welding repair area captured by the robot's camera; 2. Trajectory overlay display: Welding outline (based on the difference between the reference coordinate point and the robot coordinate, i.e., the center point of the image, and the process welding radius), and the reference center point (highlighted); 3. Interactive controls: Confirm button (highlighted in green), coordinate fine-tuning slider (weld repair center point: X / Y coordinate movement), drag correction function (weld repair center point: drag movement).

[0081] In this embodiment, the specific interaction process includes: 1) The system overlays the recommended welding trajectory and center point onto the image; 2) The operator assesses the suitability of the recommended location; 3) If the position is correct, click "Confirm" to perform the repair welding; 4) If there is a deviation, drag the center point to the correct position and confirm.

[0082] Optionally, after each weld repair is completed, the closed loop can be continuously learned and optimized, specifically including: 1) Data recording: The software records the data for this welding repair, including time, location, coordinates, welding speed, and welding power; 2) Update historical data: Automatically find the data of the corresponding product based on the product barcode and update the coordinates of the repaired welding points; 3) Log records: data change time, location, and comparison of changes before and after data. Among them, the database establishment and data update logs can establish a complete traceability system.

[0083] Based on this, the reference coordinates and statistical data can be recalculated during the next welding repair.

[0084] The welding method in this embodiment eliminates systematic errors through statistical learning and corrects random errors through human-machine collaboration to improve welding accuracy; adaptive decision calculation reduces human intervention, and improves efficiency and reduces employee workload through high-power welding in one operation. In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0085] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0086] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for welding a battery, characterized in that, The method includes: Based on the battery identification code, the original coordinates of all terminals and feature points in the first coordinate system of the pre-welding station are obtained. Then, based on the reference coordinates of the feature points in the second coordinate system of the welding station, the relative coordinates of the terminal to be repaired relative to the feature points are determined. Obtain the set of relative coordinates of the corresponding terminals to be repaired for the same type of battery in the database, in order to calculate the reference coordinates and coordinate reliability index of the terminals to be repaired; If the coordinate reliability index meets the preset requirements, then the reference coordinates are used as the point coordinates; otherwise, the difference between the reference coordinates and the corrected displacement is used as the point coordinates; the corrected displacement is an empirical value. Based on the location coordinates and relative coordinates, the coordinates for repair welding are determined and repair welding is performed.

2. The battery welding method as described in claim 1, characterized in that, Before obtaining the set of relative coordinates of the corresponding terminals to be repaired for the same battery model from the database, the following steps are also included: When welding the terminals of any battery, at the pre-welding station, the original coordinates of all terminals and two feature points of the battery in the first coordinate system are obtained, and at the welding station, the reference coordinates of the two feature points in the second coordinate system are obtained. Based on the reference coordinates of the two feature points, and the original coordinates of all poles and the two feature points, any one of the two feature points is selected as the reference feature point, and the relative coordinates of all poles relative to the reference feature point in the second coordinate system are calculated; and the reference feature points of all batteries of the same model correspond to the same feature point. Establish a mapping relationship between the battery identification code and the relative coordinates, and store the mapping relationship in a database; wherein, the relative coordinates of the terminals to be repaired corresponding to the same battery in the database constitute the set of relative coordinates.

3. The battery welding method as described in claim 1, characterized in that, Based on the location coordinates and relative coordinates, the repair welding coordinates are determined and repair welding is performed, specifically including: The difference between the point coordinates and the relative coordinates is taken as the positional deviation; The relative position of the camera and the galvanometer is obtained, and the position deviation is added to the relative position to obtain the target displacement; After moving the welding device from the position of the electrode to be repaired to the repair welding coordinate according to the target displacement, the repair welding is performed.

4. The battery welding method as described in claim 3, characterized in that, Obtaining the relative position of the camera and the galvanometer specifically includes: When repairing the pole, mark a point within the welding station, move the welding device to place the mark point in the center of the camera's field of view, and use the current coordinates of the welding device as the first coordinate; Turn on the zero-position red light preview of the galvanometer and move the welding device so that the marked point coincides with the red light, and use the current coordinates of the welding device as the second coordinate; The difference between the second coordinate and the first coordinate is used as the relative position of the camera and the galvanometer.

5. The battery welding method as described in claim 1, characterized in that, Calculate the reference coordinates of the electrode post to be repaired, specifically including: Obtain the quartiles of each dimension coordinate in the relative coordinate set, and extract the concentrated region; Calculate the average value of the coordinates in this dimension for each concentrated region, and use it as the reference coordinate.

6. The battery welding method as described in claim 5, characterized in that, The coordinate reliability index includes coordinate confidence level; The calculation of coordinate reliability indicators specifically includes: Based on the set of relative coordinates, calculate the data volume, proportion, and standard deviation of the concentrated region; A data volume score is obtained based on the data volume, a concentration score is determined based on the proportion, and a standard deviation score is obtained based on the standard deviation. The coordinate confidence score is obtained based on the data volume score, concentration score, and standard deviation score.

7. The battery welding method as described in claim 6, characterized in that, The formula for calculating the coordinate confidence level C is as follows: C = D × (λ1S + λ2I) Where D is the data volume score, S is the concentration score, I is the standard deviation score, λ1 is the weighting coefficient of the concentration score, and λ2 is the weighting coefficient of the standard deviation score.

8. The battery welding method as described in claim 7, characterized in that, Before obtaining coordinate confidence, the following steps are also included: Calculate the excess kurtosis based on the set of relative coordinates; The weighting coefficients for the concentration score and the standard deviation score are determined based on the excess kurtosis, and the larger the excess kurtosis, the larger the weighting coefficient for the concentration score.

9. The battery welding method as described in claim 6, characterized in that, The coordinate reliability index also includes the coefficient of variation; The calculated coordinate reliability index also includes: Calculate the coefficient of variation based on the standard deviation and reference coordinates; If the coefficient of variation is less than a preset coefficient, then the coefficient of variation is determined to meet the preset requirements.

10. The battery welding method as described in claim 1, characterized in that, Including two feature points, the relative coordinates of the electrode post to be repaired relative to the feature points are determined based on the reference coordinates of the feature points in the second coordinate system of the welding station. Specifically, this includes: Two feature points are photographed at the welding station to obtain the reference coordinates of the two feature points in the second coordinate system of the welding station. Choose either of the two feature points as the reference feature point. Based on the reference coordinates of the two feature points, and the original coordinates of all poles and the two feature points, calculate the relative coordinates of all poles relative to the reference feature point in the second coordinate system, and select the relative coordinates of the pole to be repaired from them; or, choose either of the two feature points as the reference feature point. Based on the reference coordinates of the two feature points, and the original coordinates of the two feature points, and select the original coordinates of the pole to be repaired, calculate the relative coordinates of the pole to be repaired relative to the reference feature point in the second coordinate system.

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