A method and system for detecting and adjusting the post-welding effect of a current collector assembly

Abstract

This invention discloses a method and system for detecting and adjusting the effect after welding of current collector composites. It utilizes a CCD camera to detect the distance between the edge of the coating in the empty foil area of ​​the composite current collector and the edge of the current collector itself. After welding, the CCD camera is used to detect the width of the weld area on both sides, the distance between the edge of the weld area and the edges of the upper and lower metal foils and the coating, and the appearance of the weld area. Based on the detected data, the distance between the weld area on both sides and the edge of the coating area, and the misalignment of the upper and lower metal foil edges are calculated. These calculated values ​​are then fed back to the metal foil unwinding and correction system and the composite current collector unwinding and correction system for real-time adjustment. This avoids the risk of one side of the weld not reaching the coating area while the other side falls into the coating area due to different coating widths on both sides during current collector coating, as well as the risk of the upper and lower metal foils covering the coating area. By enabling real-time adjustment of the metal foil unwinding and correction system and the composite current collector unwinding and correction system, the alignment of the upper and lower metal foils and the quality of the weld are ensured.

Description

Technical Field

[0001] This invention relates to the field of battery tab welding technology, specifically to a method and system for detecting and adjusting the effect after welding current collector assembly. Background Technology

[0002] Currently, copper foil is commonly used for the negative electrode current collector in power batteries, while aluminum foil is commonly used for the positive electrode current collector. However, batteries made with traditional current collectors pose a safety risk of combustion and explosion due to thermal runaway caused by dendrite growth, external forces, or other factors. Therefore, composite current collector technology has emerged. Compared to traditional single current collectors, the base film material in the composite current collector acts like a fuse. When encountering a short circuit failure mode, it can quickly break or melt, thus preventing further current conduction and ultimately stopping the cell from burning, ensuring battery safety. However, the tabs of the composite current collector cannot output the current from the cell to the electrode terminals. This necessitates the use of a connection between the tabs of a traditional current collector and the composite current collector to transfer the current from the cell.

[0003] Traditional current collectors and composite current collectors often use ultrasonic continuous welding for tab connection. Utility model patent application CN208539000U discloses a welding device and processing equipment for secondary battery current collectors. This application uses a welding device to weld foil material input to the welding station onto a portion of the composite current collector, allowing the foil material to be used as a tab for the composite current collector. Through the foil connection, the current in the battery cell can be transmitted. The processing equipment includes foil and composite current collector winding and unwinding devices, a welding device, a tension adjustment device, and a deviation correction device. Utility model patent application CN215005034U discloses a solder mark detection device, including a conveying component, a CCD detection component, and a cutting component. The conveying component conveys the product strip, and the CCD detection component and cutting component are sequentially arranged along the conveying trajectory of the product strip. The CCD detection component is used to detect the solder marks on individual items on the product strip, and the cutting component is used to remove unqualified individual items from the product strip.

[0004] However, there is currently no perfect solution for online detection and adjustment of the effect after welding traditional current collectors and composite current collectors. Issues such as the alignment of weld marks and the presence of incomplete welds are not addressed. In particular, if the coating width is inconsistent between the two sides after coating the composite current collector on both sides, there is a risk that the weld mark on one side may not reach the coated area, while the weld mark on the other side may reach the coated area. Summary of the Invention

[0005] The technical problem to be solved by this invention is to address the issue that the effect of welding traditional current collectors and composite current collectors cannot be detected and adjusted in real time.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] A method for detecting and adjusting the effect after welding a current collector assembly, wherein the current collector assembly welding structure is a layered structure, with a composite current collector in the middle, an upper metal foil layer, and a lower metal foil layer; the method includes the following steps:

[0008] S1. Before welding, collect the distances D1_front and D1_back from the edge of the composite current collector to the edge of the coating on both sides of the foil-retaining area of ​​the coated electrode, as well as the widths W1_front and W1_back of the coating area.

[0009] S2. After welding, collect the distances D2_outer (positive), D2_outer (negative), D2_inner (positive), and D2_inner (negative) from the edge of the weld stamp area on both sides; the weld stamp widths W2_positive and W2_negative on both sides; the coating area widths W3_positive and W3_negative on both sides; the distances D3_inner (positive) and D3_inner (negative) from the edge of the weld stamp area on both sides to the edge of the coating area; and the appearance of the welding area.

[0010] S3. Calculate the distances D4 inward and D4 inward from the edge of the solder area on both sides to the edge of the coating area.

[0011] S4. Calculate the misalignment of the upper and lower metal foils;

[0012] S5. Based on the distance between the soldering area on the front and back sides and the edge of the coating area, the misalignment of the upper and lower metal foils, and the welding appearance, adjust the alignment of the upper and lower metal foils and the distance between the soldering area and the edge of the coating area.

[0013] Advantages: This invention adjusts the alignment of the upper and lower metal foils and the distance between the soldering area and the edge of the coating area in real time through calculation, ensuring the alignment of the upper and lower metal foils and the quality of the soldering. It avoids the risk that the soldering on one side will not reach the coating area while the soldering on the other side falls into the coating area due to the different coating widths on both sides during current collector coating, as well as the risk that the upper and lower metal foils will cover the coating area.

[0014] Preferably, in the current collector combined welding structure, the composite current collector has been coated on both sides and has an empty foil area, and the width of the upper and lower pure metal foils is greater than the width of the empty foil area of ​​the composite current collector; wherein, during combined welding, the side closer to the welding head is the upper layer, and the side farther away from the welding head is the lower layer.

[0015] Preferably, the data acquisition step in step S1 is as follows:

[0016] S11. After the composite current collector is unwound and before it enters the welding process, add CCD linear array cameras on both the front and back sides.

[0017] S12, the CCD camera calculates the distances D1_front and D1_back from the edge of the composite current collector empty foil area to the edge of the composite current collector empty foil area based on the captured images of the edge of the composite current collector empty foil area.

[0018] S13. Calculate the widths W1_front and W1_back of the coating area on the front and back sides based on the photographed non-electrode side edge and the edge position of the coating near the empty foil area.

[0019] In combination welding, the side closer to the welding head is the front side, and the side farther from the welding head is the back side.

[0020] Preferably, the data acquisition step in step S2 is as follows:

[0021] S21. Add a CCD linear array camera to the solder area on both sides after the composite current collector is welded and before winding.

[0022] S22. Based on the positions of the two edges of the soldering area and the edges of the upper and lower metal foils captured by the CCD camera, the widths of the soldering areas on the front and back are W2_front, W2_back, the distances from the outer edge of the soldering area to the outer edge of the metal foil are D2_front_outer, D2_back_outer, and the distances from the inner edge of the soldering area to the inner edge of the metal foil are D2_front_inner, D2_back_inner.

[0023] S23. Based on the photographed edges of the non-taper side of the composite current collector and the edge of the coating near the welding area, calculate the widths W3positive and W3negative of the coating areas on the front and back sides after welding.

[0024] S24. Based on the photographed edge position of the coating near the welding area and the inner edge position of the solder area, calculate the distances D3 in the positive and negative sides of the solder area from the edge of the coating area after welding, and D3 in the negative side.

[0025] In combination welding, the side closer to the coating area is the inner side, and the side farther from the coating area is the outer side.

[0026] Preferably, in step S2, the distances D4 in the positive and negative soldering areas from the edge of the coating area are D4 in the positive and D4 in the negative. After the combined welding and before winding, the appearance of the welding area is identified by a CCD line array camera to identify appearance defects: missing welds, wrinkles in the upper and lower metal foils after welding, and damage.

[0027] Preferably, the calculation formulas for the distances D4 in the positive and negative sides of the soldering area from the edge of the coating area in step S3 are as follows:

[0028] D4 is right inside=D3 is right inside-(W1 is right-W3 is right);

[0029] D4 reverse inside = D3 reverse inside - (W1 reverse - W3 reverse);

[0030] The data used were all collected before and after welding within the same section or at the same location.

[0031] Preferably, the method for calculating the misalignment of the upper and lower metal foils in step S4 is as follows:

[0032] S41. Calculate the difference between the positive and negative values ​​of W2;

[0033] S42. If the absolute value of the difference between W2 positive and W2 negative is less than or equal to 0.2 and there are no wrinkles, damage or defects in the upper and lower metal foils in the area; then calculate the difference between D2 positive outside and D2 negative outside and the difference between D2 positive inside and D2 negative inside, and take the larger difference as the misalignment amount of the upper and lower metal foils.

[0034] S43. If the absolute value of the difference between W2 and W2 is greater than 0.2, or if there are wrinkles or damage to the upper and lower metal foils in the area, then the misalignment of this area or this position will not be included in the calculation.

[0035] Preferably, the specific steps for adjustment in step S5 are as follows:

[0036] S51. If the absolute value of the difference between W2 and W2 calculated in step S4 is less than or equal to 0.2 and there are no wrinkles, damage or defects in the upper and lower metal foils in the area;

[0037] Calculate the difference between the minimum value between D4 positive inner and D4 negative inner and the median value of the design standard distance between the inner edge of the solder area and the edge of the coating area. If the difference is within the set tolerance requirement, the unwinding correction of the composite current collector does not need to be adjusted.

[0038] If the difference exceeds the tolerance requirement, the unwinding correction of the composite current collector shall be adjusted according to the difference.

[0039] At the same time, the difference between the inner edge of D2 (positive), the inner edge of D2 (negative) and the inner edge of the soldering area and the median value of the design standard distance from the inner edge of the upper and lower metal foils is calculated, and the metal foil unwinding and correction system is adjusted according to the difference;

[0040] S52. If the absolute value of the difference between W2 and W2 is greater than 0.2, or if there are wrinkles or damage to the upper and lower metal foils in the area, the unwinding correction of this area or this position shall be adjusted according to the values ​​before the abnormality.

[0041] This invention also discloses a system for detecting and adjusting the effect of current collector assembly welding, used to detect and adjust the effect of current collector assembly welding. The current collector assembly welding structure is a layered structure, with a composite current collector in the middle, an upper metal foil layer, and a lower metal foil layer; comprising:

[0042] The pre-welding acquisition unit is used to acquire, before welding, the distances D1 (positive) and D1 (negative) from the edge of the coating on both sides of the foil-retaining area of ​​the composite current collector to the edge of the composite current collector, as well as the widths W1 (positive) and W1 (negative) of the coating area.

[0043] The post-welding acquisition unit is used to acquire the following data after welding: the distances D2 (outer side of the front), D2 (outer side of the back), D2 (inner side of the front), and D2 (inner side of the back) from the edges of the weld stamps on both sides to the edges of the upper and lower metal foils; the weld stamp widths W2 (front side) and W2 (back side) on both sides; the coating area widths W3 (front side) and W3 (back side) on both sides; the distances D3 (inner side of the front side) from the edges of the weld stamps on both sides to the edges of the coating area; and the appearance of the welding area.

[0044] The calculation unit is used to calculate the distance D4 inward and D4 inward from the edge of the soldering area on both sides to the edge of the coating area; and to calculate the misalignment of the upper and lower metal foils.

[0045] The judgment and adjustment unit is used to adjust the alignment of the upper and lower metal foils and the distance between the soldering area and the edge of the coating area based on the distance between the soldering area on the front and back sides and the edge of the coating area, the misalignment of the upper and lower metal foils, and the welding appearance.

[0046] Preferably, when the combined unit performs current collector assembly welding, the composite current collector has been coated on both sides and has an empty foil area, and the width of the upper and lower pure metal foil materials is greater than the width of the empty foil area of ​​the composite current collector; wherein, during assembly welding, the side closer to the welding head is the upper layer, and the side farther away from the welding head is the lower layer.

[0047] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention increases the distance between the edge of the coating in the composite current collector's empty foil area and the edge of the current collector itself, detected by a CCD camera. After welding, it increases the width of the welding area on both sides, the distance between the edge of the welding mark and the edges of the upper and lower metal foils and the coating, and the appearance of the welding area. Based on the detected data, it calculates the distance between the welding mark on both sides and the edge of the coating area, and the misalignment of the upper and lower metal foil edges. The calculated values ​​are then fed back to the metal foil unwinding and correction system and the composite current collector unwinding and correction system for real-time adjustment. This avoids the risk that the welding mark on one side might not reach the coating area while the welding mark on the other side falls into the coating area due to different coating widths on both sides during current collector coating, as well as the risk of the upper and lower metal foils covering the coating area. By enabling real-time adjustment of the metal foil unwinding and correction system and the composite current collector unwinding and correction system, the alignment of the upper and lower metal foils and the quality of the welding mark are guaranteed. Attached Figure Description

[0048] Figure 1 This is a top view schematic diagram of the current collector combined welding structure and various detection dimensions according to Embodiment 1 of the present invention;

[0049] Figure 2 This is a front view schematic diagram of the current collector combined welding structure and various detection dimensions according to Embodiment 1 of the present invention;

[0050] In the diagram: 1. Upper metal foil; 2. Lower metal foil; 3. Composite current collector; 31. Coated area; 4. Soldering area. Detailed Implementation

[0051] To facilitate understanding of the technical solution of the present invention by those skilled in the art, the technical solution of the present invention will now be further described in conjunction with the accompanying drawings.

[0052] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0053] Example 1

[0054] See Figure 1 and Figure 2 This embodiment discloses a method for detecting and adjusting the effect after welding current collectors together. The method involves welding current collectors together in a layered structure, with a composite current collector 3 in the middle and pure metal foils on the top and bottom layers. In the welded structure, the composite current collector 3 has been double-coated and has empty foil areas. The width of the upper and lower pure metal foils is greater than the width of the empty foil areas of the composite current collector 3. The upper and lower layers are defined as follows: during welding, the side closer to the welding head is the upper layer, and the side farther from the welding head is the lower layer. The method includes the following steps:

[0055] S1. Before welding, collect data on the distances D1 (positive) and D1 (negative) from the edge of the coating on both sides of the composite current collector 3 to the edge of the electrode foil retention area, as well as the widths W1 (positive) and W1 (negative) of the coating area 31. The specific data collection steps are as follows:

[0056] S11. After the composite current collector 3 is unwound and before it enters the welding process, add CCD linear array cameras on both the front and back sides.

[0057] S12, the CCD camera calculates the distances D1front and D1back from the edge of the front and back coatings to the edge of the empty foil area of ​​the composite current collector 3 based on the captured images of the edge of the empty foil area and the edge of the coating near the empty foil area.

[0058] S13. Based on the photographed non-electrode side edge and the edge position of the coating near the empty foil area, calculate the widths W1_front and W1_back of the front and back coating areas 31.

[0059] The positioning of the front and back sides is as follows: during combined welding, the side closer to the welding head is the front side, and the side farther away from the welding head is the back side.

[0060] S2. After welding, collect the following data: the distances D2 (outer side of front), D2 (outer side of back), D2 (inner side of front), and D2 (inner side of back) from the edges of the weld stamps in the weld stamp area 4 on both sides; the weld stamp widths W2 (front) and W2 (back); the widths W3 (front) and W3 (back) of the coating area 31 on both sides; the distances D3 (inner side of front) and D3 (inner side of back) from the edges of the weld stamps in the weld stamp area 4 on both sides; and the appearance of the welded area. The specific data collection steps are as follows:

[0061] S21. After the composite current collector 3 is welded together and before winding, a CCD linear array camera is added to the front and back solder areas 4.

[0062] S22, the CCD camera calculates the widths W2 (positive) and W2 (negative) of the soldering area 4 on both sides, the distances D2 (positive outer) and D2 (negative outer) from the outer edge of the soldering area 4 to the outer edge of the metal foil, and the distances D2 (positive inner) and D2 (negative inner) from the inner edge of the soldering area 4 to the inner edge of the metal foil based on the positions of the two edges of the soldering area 4 and the edges of the upper and lower metal foils.

[0063] S23. Based on the photographed edges of the non-electrode side of the composite current collector 3 and the edge of the coating near the welding area, calculate the widths W3 (positive) and W3 (negative) of the coating areas 31 on the front and back sides after welding.

[0064] S24. Based on the photographed edge position of the coating near the welding area and the inner edge position of the soldering area 4, calculate the distances D3 (inner for positive) and D3 (inner for negative) between the edge of the soldering area 4 on both sides and the edge of the coating area 31.

[0065] The positioning of the inner and outer sides is as follows: during combined welding, the side closer to the coating area 31 is the inner side, and the side farther away from the coating area 31 is the outer side.

[0066] S3. Calculate the distances D4 (inner side of front) and D4 (inner side of back) from the edge of the solder area 4 on both sides to the edge of the coating area 31:

[0067] The distance from the edge of the solder stamp on the front side to the edge of the coating area 31 is D4 inward = D3 inward - (W1 inward - W3 inward).

[0068] The distance from the edge of the reverse solder mark to the edge of the coating area 31 is D4 (inner side) = D3 (inner side) - (W1 (inner side) - W3 (inner side)).

[0069] The data used were all collected before and after welding within the same section or at the same location.

[0070] S4. Calculate the misalignment of the upper and lower metal foils; the method for calculating the misalignment is as follows:

[0071] S41. Calculate the difference between the positive and negative values ​​of W2.

[0072] S42. If the absolute value of the difference between W2 positive and W2 negative is less than or equal to 0.2 and there are no wrinkles, damage or defects in the upper and lower metal foils in the area, then calculate the difference between D2 positive outside and D2 negative outside and the difference between D2 positive inside and D2 negative inside, and take the larger difference as the misalignment amount of the upper and lower metal foils.

[0073] S43. If the absolute value of the difference between W2 and W2 is greater than 0.2, or if there are wrinkles or damage to the upper and lower metal foils in the area, then the misalignment of this area or this position will not be included in the calculation.

[0074] S5. Based on the distance between the front and back soldering areas 4 and the edge of the coating area 31, the misalignment of the upper and lower metal foils, and the welding appearance, feedback is given to the metal foil unwinding and correction system and the composite current collector 3 unwinding and correction system to adjust the alignment of the upper and lower metal foils and the distance between the soldering area 4 and the edge of the coating area 31. The specific method is as follows:

[0075] S51. If the absolute value of the difference between W2 (positive) and W2 (negative) is less than 0.2 and there are no wrinkles or damage to the upper and lower metal foils in the area, calculate the difference between the minimum value between D4 (positive) and D4 (negative) and the median value of the distance from the inner edge of the soldering area 4 to the edge of the coating area 31 (design standard). If the difference is within the tolerance range, the unwinding correction of the composite current collector 3 does not need to be adjusted. If the difference exceeds the tolerance range, the unwinding correction of the composite current collector 3 should be adjusted according to the difference. At the same time, calculate the difference between D2 (positive), D2 (negative), and the median value of the distance from the inner edge of the soldering area 4 to the inner edge of the upper and lower metal foils (design standard), and adjust the metal foil unwinding correction system according to the difference.

[0076] S52. If the absolute value of the difference between W2 and W2 exceeds 0.2, or if there are wrinkles or damage to the upper and lower metal foils in the area, the unwinding correction of this area or this position shall be adjusted according to the values ​​before the abnormality.

[0077] This detection and adjustment method adds CCD camera detection to measure the distance between the edge of the coating in the empty foil area of ​​the composite current collector 3 and the edge of the current collector. After welding, it adds CCD camera detection to measure the width of the front and back solder areas 4, the distance of the solder edge from the edges of the upper and lower metal foils and the coating, and the appearance of the welding area. Based on the detection data, it calculates the distance between the front and back solders and the edge of the coating area 31, and the misalignment of the upper and lower metal foil edges. The calculated values ​​are then fed back to the metal foil unwinding and correction system and the composite current collector 3 unwinding and correction system for real-time adjustment. This avoids the risk that the solder on one side will not be welded to the coating area 31 while the solder on the other side falls into the coating area 31 due to different coating widths on both sides during current collector coating, as well as the risk that the upper and lower metal foils will cover the coating area 31. By realizing real-time adjustment of the metal foil unwinding and correction system and the composite current collector 3 unwinding and correction system, the alignment of the upper and lower metal foils and the quality of the solder are guaranteed.

[0078] Based on the above-described method for detecting and adjusting the welding effect of the current collector assembly, the welding effect of the current collector assembly is detected online and adjusted in real time. The following example illustrates this in detail:

[0079] The welding effect design requirements are as follows:

[0080] 1. The distance between the inner edge of the solder mark and the inner edge of the upper and lower metal foils is 0.65±0.2mm.

[0081] 2. The misalignment of the upper and lower metal foils is ±0.2mm.

[0082] 3. The distance between the inner edge of the solder stamp and the edge of the coating is 0.8±0.2mm, calculated based on the coating edge closest to the inner edge of the solder stamp.

[0083] 4. Solder mark width 3mm.

[0084] Meanwhile, the median design width of the coating on both sides of the composite current collector 3 is 450mm, and the median design width of the empty foil area is 5mm. In the current specification, the upper and lower metal foils use 10mm wide aluminum foil, which is combined with the composite current collector 3, which has been coated on both sides according to the above requirements, using ultrasonic continuous roll welding.

[0085] Before welding, within the set area, the corresponding values ​​of the width W1 of the coating area 31 (positive and negative) collected by the CCD camera are 450.341 mm and 450.724 mm, respectively.

[0086] After welding, a CCD camera was used for real-time online inspection, and the following parameter values ​​were detected in the current area:

[0087] 1. The distances from the edge of the solder stamp in the front solder stamp area 4 to the edges of the upper and lower metal foils, D2 outer and D2 inner, are 6.192mm and 0.784mm, respectively.

[0088] 2. The distances from the edge of the solder stamp in the reverse soldering area 4 to the edges of the upper and lower metal foils, D2 (outer side) and D2 (inner side), are 6.021 mm and 0.959 mm, respectively.

[0089] 3. The widths of the solder marks on the front and back sides, W2 (front) and W2 (back), are 3.023mm and 3.020mm respectively.

[0090] 4. The corresponding widths of the front and back coating areas 31, W3 (front) and W3 (back), are 450.341 mm and 450.286 mm, respectively.

[0091] 5. The corresponding values ​​of the distances from the edge of the solder stamp in the front and back solder stamp areas 4 to the edge of the coating area 31, D3 (inner side) and D3 (inner side), are 0.996mm and 0.959mm, respectively.

[0092] Furthermore, there are no missing welds on the soldering marks, and the upper and lower metal foils are free of wrinkles and damage.

[0093] Therefore, the following data can be calculated:

[0094] 1. The distance D4 from the edge of the solder stamp on the front side to the edge of the coating area 31 is directly inside:

[0095] D4 in the center = D3 in the center - (W1 in the center - W3 in the center) = 0.996 mm - (450.341 mm - 450.341 mm) = 0.996 mm.

[0096] The distance D4 from the edge of the reverse solder mark to the edge of the coating area 31 is:

[0097] D4 inward = D3 inward - (W1 inward - W3 inward) = 0.959mm - (450.724mm - 450.286mm) = 0.521mm.

[0098] 2. Calculation of misalignment between upper and lower metal foils:

[0099] Since |W2positive - W2negative| ≤ 0.2, then calculate...

[0100] |D2 outward - D2 outward| = |6.192mm - 6.021mm| = 0.171mm.

[0101] |D2 inward - D2 outward| = |0.784mm - 0.959mm| = 0.175mm.

[0102] The misalignment of the upper and lower metal foils was then taken as 0.175 mm.

[0103] 3. Calculation for adjusting the distance between the solder stamp and the edge of the coating area (31mm):

[0104] Based on the above measurements, calculations, and requirements, it is known that:

[0105] The distance D4 inward from the edge of the front solder mark to the edge of the coating area 31 is 0.996mm; the distance D4 inward from the edge of the back solder mark to the edge of the coating area 31 is 0.521mm.

[0106] The design median distance between the inner edge of the solder mark and the edge of the coating is 0.8 ± 0.2 mm.

[0107] Then it can be calculated that (+ represents outward adjustment, - represents inward adjustment):

[0108] The difference between the inner edge of the solder stamp and the edge of the coating area 31, D4, and the inner edge of the solder stamp and the edge of the coating area is +0.196mm.

[0109] The difference between the design median distance D4, the distance from the edge of the reverse solder stamp to the edge of the coating area 31, and the distance from the inner edge of the solder stamp to the edge of the coating is -0.279mm.

[0110] The larger of the differences is -0.279mm, which means that the unwinding correction of the composite current collector 3 is adjusted inward by 0.279mm.

[0111] 4. Calculation for alignment adjustment of upper and lower metal foils:

[0112] Based on the above measurements, calculations, and requirements, it is known that:

[0113] D2 inward = 0.784 mm; D2 outward = 0.959 mm.

[0114] The required distance between the inner edge of the solder mark and the inner edge of the upper and lower metal foils is 0.65±0.2mm.

[0115] Then it can be calculated that (+ represents outward adjustment, - represents inward adjustment):

[0116] The distances between the inner edge of the solder stamp in the positive and negative solder stamp areas 4 and the inner edges of the upper and lower metal foils, D2 (positive inner) and D2 (negative inner), differ from the design requirements by +0.134mm and +0.309mm, respectively.

[0117] Based on the calculated data above, the adjustments required for the unwinding and correction system are as follows:

[0118] 1. The composite current collector 3 is unwound and the deviation is corrected inward by 0.279mm.

[0119] 2. Unwind the upper metal foil material 1 and adjust it outward by 0.134mm.

[0120] 3. Adjust the unwinding and correction of the lower metal foil material by 0.309mm.

[0121] In the following area, if the corresponding values ​​of the solder mark width W2 (positive) and W2 (negative) are detected to be 3.323 mm and 3.020 mm respectively, or if the lower metal foil 2 is found to be severely wrinkled near the welding area, the unwinding and correction system in this area will still be adjusted according to the adjustment amount of the above area.

[0122] Example 2

[0123] This embodiment also discloses a system for detecting and adjusting the effect after welding current collector assemblies, used for welding current collector assemblies. The structure is a layered structure, with a composite current collector 3 in the middle and pure metal foils on the upper and lower layers, including:

[0124] The pre-welding acquisition unit is used to acquire, before welding, the distances D1 (front) and D1 (back) from the edge of the coating on both sides of the foil-retaining area of ​​the composite current collector 3 to the edge of the composite current collector 3, as well as the widths W1 (front) and W1 (back) of the coating area 31.

[0125] The post-welding acquisition unit is used to acquire the following data after welding: the distances D2 (outer side of the front), D2 (outer side of the back), D2 (inner side of the front), and D2 (inner side of the back) from the edge of the weld stamp area 4 on both sides to the edges of the upper and lower metal foils; the weld stamp widths W2 (front side) and W2 (back side) on both sides; the widths W3 (front side) and W3 (back side) of the coating area 31 on both sides; the distances D3 (inner side of the front side) and D3 (inner side of the back side) from the edge of the weld stamp area 4 on both sides to the edge of the coating area 31; and the appearance of the welding area.

[0126] The calculation unit is used to calculate the distances D4 in the positive and negative sides of the solder stamp edge from the edge of the coating area 31, and D4 in the negative side; and to calculate the misalignment of the upper and lower metal foils.

[0127] The judgment and adjustment unit is used to adjust the alignment of the upper and lower metal foils and the distance between the solder stamp and the edge of the coating area 31 based on the distance between the solder stamp on the front and back sides and the edge of the coating area 31, the misalignment of the upper and lower metal foils, and the welding appearance.

[0128] When the current collector is combined and welded, the composite current collector 3 has been coated on both sides and has an empty foil area. The width of the upper and lower pure metal foils is greater than the width of the empty foil area of ​​the composite current collector 3. During the combined welding, the side closer to the welding head is the upper layer and the side farther away from the welding head is the lower layer.

[0129] The pre-welding data acquisition unit includes:

[0130] The pre-welding imaging unit adds CCD line array cameras on both the front and back sides after the composite current collector 3 is unwound and before it enters the welding process.

[0131] Before welding, the CCD camera calculates the distances D1positive and D1negative from the edge of the composite current collector 3 empty foil area to the edge of the empty foil area based on the captured images of the edge of the positive and negative composite current collector 3 empty foil area. Based on the captured images of the non-tab side edge and the edge of the coating near the empty foil area, the widths W1positive and W1negative of the positive and negative coating areas 31 are calculated.

[0132] In combination welding, the side closer to the welding head is the front side, and the side farther from the welding head is the back side.

[0133] The post-welding acquisition unit includes:

[0134] The post-welding imaging unit adds a CCD line array camera to the front and back solder areas 4 after the composite current collector 3 is assembled and welded and before winding.

[0135] The post-welding calculation unit, based on the positions of the two edges of the weld and the edges of the upper and lower metal foils captured by the CCD camera, calculates the weld widths W2positive and W2negative on both sides, the distances from the outer edge of the weld to the outer edge of the metal foil D2positive and D2negative on both sides, and the distances from the inner edge of the weld to the inner edge of the metal foil D2positive and D2negative on both sides.

[0136] Based on the photographed edges of the non-electrode side of the composite current collector 3 and the edge of the coating near the welding area, the widths W3 (positive) and W3 (negative) of the coating areas 31 on the front and back sides after welding are calculated.

[0137] Based on the photographed edge position of the coating near the welding area and the inner edge position of the weld mark, the distances D3 in the front and D3 in the back of the weld mark area 4 from the edge of the coating area 31 after welding are calculated.

[0138] During combined welding, the side closer to the coating area 31 is the inner side, and the side farther from the coating area 31 is the outer side.

[0139] The computing unit includes:

[0140] The internal calculation formulas for D4 inner and D4 outer calculation units are as follows:

[0141] D4 is right inside=D3 is right inside-(W1 is right-W3 is right);

[0142] D4 reverse inside = D3 reverse inside - (W1 reverse - W3 reverse);

[0143] The data used were all collected before and after welding within the same section or at the same location.

[0144] Misalignment calculation unit:

[0145] This is used to calculate the difference between the positive and negative sides of W2. If the absolute value of the difference between the positive and negative sides of W2 is less than or equal to 0.2 and there are no wrinkles, damages, or defects in the upper and lower metal foils in the area, then the difference between the outer side of D2 and the outer side of D2 and the difference between the inner side of D2 and the inner side of D2 is calculated, and the larger difference is taken as the misalignment amount of the upper and lower metal foils. If the absolute value of the difference between the positive and negative sides of W2 is greater than 0.2 or there are wrinkles, damages, or defects in the upper and lower metal foils in the area, then the misalignment amount of this area or this position is not included in the calculation.

[0146] The adjustment unit includes:

[0147] Judgment Unit: Used to determine the absolute value of the difference between W2 positive and W2 negative values ​​and 0.2, and whether the upper and lower metal foils in the area are wrinkled, damaged or defective.

[0148] In the first adjustment unit, if the absolute value of the difference between W2 positive and W2 negative is less than or equal to 0.2 and there are no wrinkles or damage to the upper and lower metal foils in the area; calculate the difference between the minimum value between D4 positive inner and D4 negative inner and the median value of the distance from the inner edge of the solder stamp to the edge of the coating area 31 in the design standard; if the difference is within the set tolerance requirements, the unwinding correction of the composite current collector 3 does not need to be adjusted; if the difference exceeds the tolerance requirements, the unwinding correction of the composite current collector 3 is adjusted according to the difference; at the same time, calculate the difference between D2 positive inner, D2 negative inner and the median value of the distance from the inner edge of the solder stamp to the inner edge of the upper and lower metal foils in the design standard, and the metal foil unwinding correction system is adjusted according to the difference.

[0149] The second adjustment unit, if the absolute value of the difference between W2 and W2 is greater than 0.2 or if there are wrinkles or damage to the upper and lower metal foils in the area, then the unwinding correction of this area or this position will be adjusted according to the values ​​before the abnormality.

[0150] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0151] The above embodiments are merely examples of implementation methods of the invention. The scope of protection of the present invention is not limited to the above embodiments. For those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A method for detecting and adjusting the effect after welding a current collector assembly, wherein the current collector assembly welding structure is a layered structure, with a composite current collector (3) in the middle, an upper metal foil (1) on top, and a lower metal foil (2) on the bottom; characterized in that: Includes the following steps: S1. Before welding the current collector assembly, collect the distances from the edge of the coating area (31) of the composite current collector (3) to the edge of the electrode foil retention area on both sides, namely D1 (positive) and D1 (negative), and the width of the coating area (31) W1 (positive) and W1 (negative) W1 (negative) W1. S2. After welding, collect the distances from the edge of the weld stamp (4) on the front and back sides to the edges of the upper and lower metal foils: D2 front outside, D2 back outside, D2 front inside, D2 back inside; the weld stamp widths on the front and back sides: W2 front, W2 back; the widths of the coating areas (31) on the front and back sides: W3 front, W3 back; collect the distances from the edge of the weld stamp (4) on the front and back sides to the edge of the coating area (31): D3 front inside, D3 back inside; collect the appearance of the welding area. S3. Calculate the distances D4 in the front and back soldering areas (4) from the edge of the coating area (31) to the edge of the coating area (31); S4. Calculate the misalignment between the upper and lower metal foil layers; S5. Based on the distance between the front and back soldering areas (4) and the edge of the coating area (31), the misalignment of the upper and lower metal foils, and the welding appearance, adjust the alignment of the upper metal foil (1) and the lower metal foil (2) and the distance between the soldering area (4) and the edge of the coating area (31).

2. The method for detecting and adjusting the effect after welding of current collector assembly according to claim 1, characterized in that: In the current collector combined welding structure, the composite current collector (3) has been coated on both sides and has a blank foil area. The width of the upper and lower pure metal foils is greater than the width of the blank foil area of ​​the composite current collector (3). When combined welding, the side closer to the welding head is the upper layer and the side farther away from the welding head is the lower layer.

3. The method for detecting and adjusting the effect after welding of current collector assembly according to claim 1, characterized in that: The data acquisition steps in step S1 are as follows: S11. After the composite current collector (3) is unwound and before it enters the welding process, add a CCD linear array camera on both the front and back sides. S12, the CCD camera calculates the distances D1_front and D1_back from the edge of the empty foil area of ​​the composite current collector (3) on both sides based on the edge of the empty foil area and the edge of the coating film near the empty foil area captured by the image. S13. Based on the photographed non-electrode side edge and the edge position of the coating near the empty foil area, calculate the widths W1_front and W1_back of the coating area (31) on the front and back sides. In combination welding, the side closer to the welding head is the front side, and the side farther from the welding head is the back side.

4. The method for detecting and adjusting the effect after welding of current collector assembly according to claim 1, characterized in that: The data acquisition steps in step S2 are as follows: S21. After the composite current collector (3) is welded together and before winding, a CCD linear array camera is added to the front and back solder areas (4). S22. Based on the positions of the two edges of the soldering area (4) and the positions of the upper and lower metal foils captured by the CCD camera, the widths W2 of the soldering area (4) on the front and back sides, W2 of the back side, the distances from the outer edge of the soldering area (4) to the outer edge of the metal foil D2 of the front side and D2 of the back side, and the distances from the inner edge of the soldering area (4) to the inner edge of the metal foil D2 of the front side and D2 of the back side are calculated. S23. Based on the photographed position of the non-electrode side edge of the composite current collector (3) and the edge of the coating near the welding area, calculate the widths W3 of the coating area (31) on the front and back sides after welding, W3 and W3 respectively. S24. Based on the photographed edge position of the coating near the welding area and the inner edge position of the soldering area (4), calculate the distances D3 in the front and back sides of the soldering area (4) from the edge of the coating area (31) after welding: D3 in the front and D3 in the back. During combined welding, the side closer to the coating area (31) is the inner side, and the side farther away from the coating area (31) is the outer side.

5. The method for detecting and adjusting the effect after welding of current collector assembly according to claim 1, characterized in that: In step S3, the distance between the edge of the positive and negative soldering area (4) and the edge of the coating area (31) is D4 in the positive direction and D4 in the negative direction. After the combined welding and before winding, the appearance of the welding area is identified by a CCD line array camera to identify appearance defects: missing welding, wrinkles of the upper and lower metal foils after welding, and damage.

6. The method for detecting and adjusting the effect after welding of current collector assembly according to claim 5, characterized in that: The formulas for calculating the distances D4 in the front and back solder areas (4) from the edge of the coating area (31) in step S3 are as follows: D4 is inside=D3 is inside-(W1 is inside-W3 is inside); D4 anti-inner = D3 anti-inner - (W1 anti-W3 anti); The data used were all collected before and after welding within the same section or at the same location.

7. The method for detecting and adjusting the effect after welding current collector assembly according to claim 1, characterized in that: The calculation method for the misalignment of the upper and lower metal foils in step S4 is as follows: S41. Calculate the difference between the positive and negative values ​​of W2; S42. If the absolute value of the difference between W2 positive and W2 negative is less than or equal to 0.2 and there are no wrinkles, damage or defects in the upper and lower metal foils in the area; then calculate the difference between D2 positive outside and D2 negative outside and the difference between D2 positive inside and D2 negative inside, and take the larger difference as the misalignment amount of the upper and lower metal foils. S43. If the absolute value of the difference between W2 and W2 is greater than 0.2, or if there are wrinkles or damage to the upper and lower metal foils in the area, then the misalignment of this area will not be included in the calculation.

8. The method for detecting and adjusting the effect after welding of current collector assembly according to claim 7, characterized in that: The specific steps for adjustment in step S5 are as follows: S51. If the absolute value of the difference between W2 and W2 calculated in step S4 is less than or equal to 0.2 and there are no wrinkles, damage or defects in the upper and lower metal foils in the area; Calculate the difference between the minimum value between D4 positive inner and D4 negative inner and the design standard median value of the distance between the inner edge of the solder area (4) and the edge of the coating area (31). If the difference is within the set tolerance requirement, the unwinding correction of the composite current collector (3) does not need to be adjusted. If the difference exceeds the tolerance requirement, the unwinding and correction of the composite current collector (3) shall be adjusted according to the difference; At the same time, calculate the difference between the inner edge of D2 positive, D2 negative and the inner edge of the soldering area (4) and the median value of the design standard distance from the inner edge of the upper and lower metal foils, and adjust the metal foil unwinding and correction system according to the difference; S52. If the absolute value of the difference between W2 and W2 is greater than 0.2, or if there are wrinkles or damage to the upper and lower metal foils in the area, the unwinding correction of this area shall be adjusted according to the values ​​before the abnormality.

9. A system for detecting and adjusting the effect of current collector assembly welding, used to detect and adjust the effect of current collector assembly welding, wherein the current collector assembly welding structure is a layered structure, with a composite current collector (3) in the middle, an upper metal foil (1) on top, and a lower metal foil (2) on the bottom; characterized in that: include The pre-welding acquisition unit is used to collect the distances D1 (positive) and D1 (negative) from the edge of the coating on the front and back sides of the foil-retaining area of ​​the composite current collector (3) to the edge of the composite current collector (3) before welding, as well as the widths W1 (positive) and W1 (negative) of the coating area (31). The post-welding acquisition unit is used to collect the following data after welding: the distances from the edge of the weld stamp (4) on both sides to the edges of the upper and lower metal foils: D2 (outer side), D2 (outer side), D2 (inner side), D2 (inner side); the widths of the weld stamp (4) on both sides: W2 (positive side) and W2 (negative side); the widths of the coating areas (31) on both sides: W3 (positive side) and W3 (negative side); the distances from the edge of the weld stamp (4) on both sides to the edge of the coating area (31): D3 (inner side) and D3 (negative side); and the appearance of the welding area. The calculation unit is used to calculate the distance D4 in the front and back soldering areas (4) from the edge of the coating area (31) to the edge of the coating area (31); and to calculate the misalignment of the upper and lower metal foils. The judgment and adjustment unit is used to adjust the alignment of the upper and lower metal foils and the distance between the soldering area (4) and the edge of the coating area (31) based on the distance between the soldering area (4) and the edge of the coating area (31), the misalignment of the upper and lower metal foils, and the welding appearance.

10. The current collector assembly welding effect detection and adjustment system according to claim 9, characterized in that: When the combined unit performs current collector combination welding, the composite current collector (3) has been coated on both sides and has a blank foil area. The width of the upper and lower pure metal foils is greater than the width of the blank foil area of ​​the composite current collector (3). Among them, during combination welding, the side closer to the welding head is the upper layer and the side farther away from the welding head is the lower layer.

Images