Bus bar splicing process

Abstract

The invention relates to the technical field of photovoltaic modules, in particular to a bus bar splicing process. In the bus bar splicing process, the tail area of the previous bus bar and the head area of the next bus bar are stacked up and down, so that the two bus bars form an overlapping area with a preset length in the length direction; according to the method, the two bus bars are overlapped, then the tongue piece is manufactured in the overlapped area of the two bus bars, then the tongue piece is folded and pressed tightly, continuous connection of the two bus bars is achieved, absolute dependence of traditional resistance welding on the surface conditions and conductivity of the bus bars is eliminated, and the problem of production interruption caused by insufficient welding is solved. Moreover, since current conduction is not needed, the bus bar with the surface covered with the insulating coating can still be applied, and the application range of the process is greatly widened.

Description

Technical Field

[0001] This application relates to the field of photovoltaic module technology, and in particular to a busbar splicing process. Background Technology

[0002] In photovoltaic module production, busbars, as crucial long conductive strips, are used to collect and transmit the current generated by the solar cells. When a roll of busbars runs out, its tail needs to be connected to the head of a new roll to ensure continuous production. Currently, the common method is to stack the heads and tails of the old and new rolls of busbars one on top of the other and perform resistance welding by applying current through electrodes. This process relies on the tin layer pre-coated on the surface of the busbars melting when heated to form a metal fusion, thus achieving the connection. The welded busbar is then pulled to the next workstation.

[0003] However, this resistance welding method has significant limitations in practical applications. Its success depends heavily on the tight contact between the overlapping areas of the two busbars. Misalignment, gaps, or uneven pressure can easily lead to insufficient heating, resulting in incomplete welds or even failure to join at all, severely impacting production speed. Moreover, to meet the climate resistance and insulation requirements of certain components, some busbars are coated with black insulating varnish. This coating completely blocks the conduction of welding current, making resistance welding impossible on such busbars with insulating coatings. Summary of the Invention

[0004] (a) The problem to be solved by this application is that the existing busbar splicing mostly adopts resistance welding, which has the problems of low reliability and poor compatibility.

[0005] (II) Technical Solution To address the aforementioned technical issues, this application provides a busbar splicing process, which is applied in photovoltaic module production to splice the tail of one busbar to the head of another; wherein the width of the busbar is 4-6mm. Busbar splicing process includes: The tail region of the previous busbar and the head region of the next busbar are stacked one on top of the other, so that the two busbars form a pre-defined overlapping region in the length direction. Within the overlapping area, tongues are made at the edge of the long side of each busbar by stamping or shearing; wherein: the tongue has a connecting part 111 connected to the busbar, the tongues on the two busbars correspond one to one, and the two corresponding tongues form a tongue unit. The two tongues of the tongue unit are simultaneously folded around the connecting part 111 toward the center line of the busbar length direction; Press the folded tongue unit against the bus bar to complete the connection between the tail area of ​​the previous bus bar and the head area of ​​the next bus bar.

[0006] By creating a tongue at the overlapping area of ​​two busbars and then folding and pressing the tongue together, the two busbars are joined. This approach eliminates the absolute dependence of traditional resistance welding on the surface condition and conductivity of the busbars, completely resolving production interruptions caused by incomplete welds. Secondly, the entire joining process requires no current flow, and busbars with insulating coatings are still applicable, greatly expanding the scope of application. Thirdly, creating the tongue at the edge of the long side of the busbar, compared to placing it in the center, avoids the problem of minimal allowance on both sides of the busbar body due to narrow width, which could easily lead to breakage at the joint under traction during subsequent production. Fourthly, compared to resistance welding, it eliminates the need for a resistance welding power supply and control system, significantly reducing the cost of busbar joining.

[0007] Optionally, within the overlapping area, a tongue is fabricated at the edge of the long side of each busbar using a stamping or shearing process, including: Within the overlapping area, tongues are made at the edges of the two long sides of each busbar by stamping or shearing. The tongues on the two long sides of the busbar are completely offset from each other along the length of the busbar.

[0008] The distribution of the tongues is planned according to the length of the overlapping area to ensure that the tongues on the two long edges of the busbar are completely staggered along the length of the busbar, thereby avoiding the busbar body being too narrow and prone to breakage, and ensuring that the two busbars after splicing are stable and reliable in the stress scenarios such as traction and bending during photovoltaic module production.

[0009] Optionally, the number of tongues is at least three, and the tongues on the two long sides of the busbar are arranged alternately along the length of the busbar.

[0010] The number of tongues is at least three, and each tongue is alternately arranged on the two long sides of the busbar, so that there are multiple connection points at the joint, making the force distribution more uniform and the connection strength higher.

[0011] Optionally, at least two tongues are made on the first long side of the busbar, and at least one tongue is made on the second long side of the busbar. The distance between the centers of two adjacent tongues on the first long side of the busbar is L1, and the length of the tongue on the second long side of the busbar is L2, where: L1 > 2 × L2.

[0012] The center-to-center distance between two tongues on the same long side of the busbar is greater than twice the length of the tongue, ensuring that each tongue can fold towards the centerline of the busbar without interfering with each other. This also guarantees the connection strength at the joint, preventing weakening of the busbar's edge structure due to overly dense tongues. Consequently, during subsequent production, when the busbar is subjected to traction, the joint is less likely to break due to insufficient body strength.

[0013] Optionally, the two tongues of the tongue unit are simultaneously folded around the connecting portion toward the centerline of the busbar length, including: The two tongues of the tongue unit are simultaneously folded upwards around the connecting part towards the center line of the busbar length direction, so that the two tongues of the tongue unit are folded to the upper side of the busbar above. Alternatively, both tongues of the tongue unit can be folded downwards along the center line of the busbar length direction around the connecting part, so that the two tongues of the tongue unit are folded to the lower side of the busbar.

[0014] By setting two folding methods and two folding directions, the applicability is enhanced, and the choice can be made flexibly according to production needs. Folding upwards facilitates visual inspection of the tongue's fit, thereby promptly identifying problems such as incomplete folding or loose fit; folding downwards allows the tongue to be hidden under the manifold strip, preventing accidental scratches or damage to the tongue during subsequent traction and handling.

[0015] Optionally, each busbar has a tongue at the edge of both long sides, with at least three tongues. The tongues at the edges of the two long sides of the busbar are staggered along the length of the busbar. The two tongues of each tongue unit are simultaneously folded around the connecting portion towards the centerline of the busbar's length direction, including: At least one tongue unit has its two tongues simultaneously folded upwards around the connecting portion toward the center line of the busbar length direction, so that the two tongues of the tongue unit are folded to the upper side of the busbar above; the remaining tongue units have their two tongues simultaneously folded downwards around the connecting portion toward the center line of the busbar length direction, so that the two tongues of the tongue unit are folded to the lower side of the busbar below.

[0016] The two tongues of some tongue units are folded upwards and the two tongues of some tongue units are folded downwards, forming a two-way mechanical locking structure at the joint. This allows the two busbars to be firmly fixed along the length direction, making them more resistant to deformation and further enhancing the structural strength of the joint. It avoids the risk of breakage caused by excessive force on one side, and there is no interference between tongue units with different folding directions.

[0017] Optionally, the shape of the tongue can be any one or at least a combination of two of the following: rectangular, trapezoidal, triangular, M-shaped, circular, semi-circular, elliptical, serrated, and wavy. When the shape of the tongue is trapezoidal, the long side of the tongue is the connecting part connected to the busbar.

[0018] The diverse tongue shapes allow the busbar splicing process to adapt to different stress requirements and production scenarios, improving the flexibility and applicability of the process. Moreover, when the tongue is trapezoidal, the long side of the tongue is the connecting part that connects to the busbar, which can enhance the connection strength between the tongue and the busbar body.

[0019] Optionally, the tongue unit pressing against the contact busbar is the first tongue, and the area where the busbar contacts the first tongue is the first region; before simultaneously folding the two tongues of the tongue unit around the connecting portion towards the centerline of the busbar's length direction, the method further includes: Apply adhesive to the surface of the first tongue facing the first region; and / or apply adhesive to the first region.

[0020] By applying an adhesive, a dual fixing effect of mechanical locking and adhesive fixation is achieved, which greatly improves the connection strength and stability between the two busbars.

[0021] Optionally, after pressing the folded tongue unit against the busbar in the step, the method further includes: The folded tongue unit and busbar are subjected to roller pressing or secondary pressing.

[0022] Rolling or secondary pressing improves the fit between the tongue and the busbar, enhancing the tensile, shear, and vibration resistance of the joint, thus better enabling it to withstand various external forces during photovoltaic module production and use. Simultaneously, rolling or secondary pressing can correct slight misalignments or warping that may occur during folding, ensuring the flatness of the joint.

[0023] Optionally, the width of the tongue is w, where 1mm ≤ w ≤ 3mm.

[0024] The 1-3mm width range of the tongue plate, compared to the 4-6mm width of the busbar, ensures that the tongue plate has sufficient structural strength while avoiding the problem of insufficient margin at the edge of the busbar due to an excessively wide tongue plate. While ensuring the performance of the tongue plate itself, it also preserves the structural integrity of the busbar body to the maximum extent, making the joint both firm and not easy to break. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 A flowchart illustrating the busbar splicing process provided in this application embodiment; Figure 2 This is a side view showing the tail of the previous busbar 100 and the head of the next busbar 100 stacked one on top of the other. Figure 3 A schematic diagram of the manifold after the rectangular tongue is fabricated; Figure 4 This is a schematic diagram of the rectangular tongue after it has been folded over; Figure 5 This is a schematic diagram showing the two tongues aligned and positioned on the two long sides of the busbar. Figure 6 This is a schematic diagram showing two tongues that are partially offset and positioned on the two long sides of the busbar. Figure 7 A schematic diagram of the busbar after the trapezoidal tongue is fabricated; Figure 8 This is a schematic diagram of the trapezoidal tongue after it has been folded. Figure 9 This is a schematic diagram showing the dimensions of the relevant tongues in the manifold after the rectangular tongues have been fabricated; Figure 10 A schematic diagram of a manifold with rectangular and trapezoidal tongues; Figure 11 A schematic diagram for creating a busbar with triangular, M-shaped, circular, semi-circular, elliptical, serrated, and wavy tongues.

[0027] Icons: 100 - Busbar; 110 - Tongue; 111 - Connecting part. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0031] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application 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 on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0032] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0033] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0034] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0035] This application provides a busbar splicing process. This process is applied in photovoltaic module production to connect the tail of one busbar 100 to the head of another. The busbar 100 has a long, strip-like structure, typically with a width of 4-6 mm. In photovoltaic modules, the busbar 100 primarily collects the current generated by multiple cell strings and transmits it to the junction box for power output; it is a key conductive component connecting the cell strings to external circuits. Figures 1 to 4 As shown, the busbar splicing process includes: The tail region of the preceding busbar 100 and the head region of the following busbar 100 are stacked vertically (it should be noted that "stacked vertically" means that the surfaces of the tail region of the preceding busbar 100 and the head region of the following busbar 100 overlap vertically after being stacked, and does not limit which of the tail region of the preceding busbar 100 and the head region of the following busbar 100 is placed below or above), so that the two busbars 100 form an overlapping area of ​​a preset length in the length direction; Within the overlapping area, a tongue 110 is made at the edge of the long side of each busbar 100 by a stamping or shearing process; wherein: the tongue 110 has a connecting portion 111 connected to the busbar 100, the tongues 110 on the two busbars 100 correspond one to one, and the two corresponding tongues 110 form a tongue unit. The two tongues 110 of the tongue unit are simultaneously folded around the connecting part 111 toward the center line of the busbar 100 in the length direction; The folded tongue unit is pressed against the busbar 100 to complete the connection between the tail region of the previous busbar 100 and the head region of the next busbar 100.

[0036] In this embodiment, firstly, as Figure 2As shown, the tail region of the first busbar 100 and the head region of the second busbar 100 are aligned and stacked together to ensure that the long edges of the two busbars 100 can be completely attached, thereby forming an overlapping area along the length of the busbar 100; the length of the overlapping area can be set according to the actual use scenario and traction requirements of the busbar 100. Next, within the overlapping area, tongues 110 are fabricated at the long edge of each busbar 100 using either a stamping or shearing process. When using the shearing process, a suitable cutting tool is selected to cut along the long edge of the busbar 100 towards the centerline of the busbar's length. When using the stamping process, a stamping die corresponding to the shape and position of the tongue 110 is selected to stamp the tongue 110 at the long edge of the busbar 100. Since the two busbars 100 are pre-stacked, the tongues 110 on the two busbars 100 are fabricated simultaneously; that is, the two tongues 110 of the same tongue unit are formed in one step using a set of cutting tools or stamping dies. After the tongues 110 are fabricated, the tongues 110 on the two busbars 100 correspond one-to-one, with their shapes and positions completely overlapping. Each pair of corresponding tongues 110 forms a tongue unit. Subsequently, the two tongues 110 of the same tongue unit are simultaneously folded around their respective connection portions 111 with the busbar 100 towards the centerline of the busbar 100's length. Finally, the folded tongue unit is pressurized to press and tightly adhere the tongues 110 to the surface of the busbar 100, achieving relative mechanical fixation of the two busbars 100 in the length direction, thus completing the continuation of the two busbars 100. The busbar continuation process provided in this application achieves the continuation of the two busbars 100 by creating tongues 110 in the overlapping area of ​​the two busbars 100 and then folding and pressing the tongues 110. This fundamentally eliminates the absolute dependence of traditional resistance welding on the surface condition and conductivity of the busbar 100, completely solving the production interruption problem caused by poor welding. Moreover, since the entire continuation process does not require current conduction, it is still applicable to busbars 100 with an insulating coating on their surface, greatly expanding the applicability of this process.

[0037] Furthermore, fabricating the tongue 110 at the edge of the long side of the busbar 100, compared to fabricating the tongue 110 in the center of the busbar 100, avoids the problem of minimal margin on both sides of the busbar 100 body due to the narrow width of the busbar 100, which could easily lead to breakage at the joint under traction force during subsequent production. Since the busbar 100 is 4-6mm wide, a narrow and long strip structure, and in photovoltaic module production, the connected busbar 100 needs to continuously withstand traction force along its length. If the tongue 110 is fabricated in the center of the busbar 100, the tongue 110 itself would occupy 1-3mm of width space. This would cause the busbar 100 body on both sides of the tongue 110 to be compressed to a smaller area. This narrow margin must simultaneously bear the traction force during production and the stress generated by the connection of the tongue 110, resulting in insufficient effective bearing area and making the joint extremely prone to breakage. Furthermore, the narrow and dispersed allowances on both sides, without effective connection, result in poor torsional and bending resistance of the busbar 100. Even slight bending or torsion during production can cause cracks in the allowance area of ​​the busbar 100, eventually leading to breakage. However, by fabricating the tongue 110 at the edge of the long side of the busbar 100, the tongue 110 only occupies the edge portion in the width direction of the busbar 100 and does not intrude into the central area. This allows for the retention of more allowance in the busbar 100 body. This uncut area can withstand longitudinal tensile forces, lateral bending forces, and torsional forces during production, avoiding load-bearing failure due to insufficient allowance.

[0038] Furthermore, the busbar splicing process proposed in this application does not require a resistance welding power supply and control system compared to the resistance welding splicing method, which can significantly reduce the cost of busbar splicing.

[0039] In an optional embodiment of this application, in the overlapping area, the tongue 110 is fabricated at the edge of the long side of each busbar 100 by a stamping or shearing process, including: Within the overlapping area, tongues 110 are made at the edges of the two long sides of each busbar 100 by stamping or shearing. The tongues 110 located on the two long sides of the busbar 100 are completely offset from each other along the length of the busbar 100.

[0040] like Figure 5 , 6 As shown, the tongues 110 located on the two long sides of the busbar 100 are not staggered or only partially staggered along the length of the busbar 100. In this case, the distance r between the two tongues 110 on the two long sides is too narrow, making the busbar 100 body too narrow between the two tongues 110. When a traction force is applied to the busbar after it is connected, it is easy for the busbar to break.

[0041] In this embodiment, the distribution of the tongues 110 is planned according to the length of the overlapping area to ensure that the tongues 110 on the two long edges of the busbar 100 are completely staggered along the length of the busbar 100, thereby avoiding the busbar 100 body being too narrow and easily broken, and ensuring that the two busbars 100 after splicing are stable and reliable in the stress scenarios such as traction and bending during photovoltaic module production.

[0042] In an optional embodiment of this application, the number of tongues 110 is at least three, and the tongues 110 on the two long sides of the busbar 100 are arranged alternately along the length direction of the busbar 100.

[0043] In this embodiment, there are at least three tongues 110, and each tongue 110 is alternately arranged on the two long sides of the busbar 100, thereby providing multiple connection points at the joint, resulting in a more uniform force distribution and higher connection strength. During the manufacturing process, whether the two busbars 100 are subjected to longitudinal tension or lateral bending force, the force can be shared by the multiple tongues 110, avoiding structural failure caused by excessive local stress. Furthermore, even if individual tongues 110 have minor defects during manufacturing or use, it will not affect the overall connection strength, further ensuring the stability of the joint.

[0044] In an optional embodiment of this application, at least two tongues 110 are formed on the first long side of the busbar 100, and at least one tongue is formed on the second long side of the busbar. The distance between the centers of two adjacent tongues 110 on the first long side of the busbar 100 is L1, and the length of the tongue 110 on the second long side of the busbar is L2, wherein: L1 > 2 × L2.

[0045] It should be noted that the center of the aforementioned tongue is the geometric center of the tongue, such as... Figure 9 As shown, the tongue is rectangular in shape, therefore its center is the intersection of its two diagonals. The length of the tongue refers to the straight-line distance between the two furthest points on the tongue along the length of the busbar. Figure 9 The tongue shown is rectangular, and its length is the same as the length of the long side of the rectangle.

[0046] In this embodiment, the center-to-center distance between two tongues 110 on the same long side of the busbar 100 is greater than twice the length of the tongue 110. This ensures that each tongue 110 can fold towards the centerline of the busbar 100, and that adjacent tongues 110 do not interfere with each other. Simultaneously, it guarantees the connection strength at the joint, preventing weakening of the edge structure of the busbar 100 due to excessively dense tongues 110. This makes it less likely for the joint to break due to insufficient body strength when the busbar 100 is subjected to traction or bending during subsequent production.

[0047] In an optional embodiment of this application, the two tongues 110 of the tongue unit are simultaneously folded around the connecting portion 111 toward the center line of the busbar 100 along its length, including: The two tongues 110 of the tongue unit are simultaneously folded upward around the connecting portion 111 toward the center line of the busbar 100 in the length direction, so that the two tongues 110 of the tongue unit are folded to the upper side of the busbar 100 above. Alternatively, the two tongues 110 of the tongue unit can be folded downwards around the connecting portion 111 toward the center line of the busbar 100 in the length direction, so that the two tongues 110 of the tongue unit are folded to the lower side of the busbar 100.

[0048] In this embodiment, the tongue 110 can be folded upwards or downwards. When the tongue 110 is folded upwards, the two stacked busbars 100 can be fixed on the worktable using a positioning fixture. The fixture supports the bottom of the lower busbar 100 to ensure that the busbar 100 does not shift during the folding process. Then, an upward force can be applied to the two tongues 110 of the same tongue unit using a corresponding folding tool or manual operation, which will simultaneously drive the two tongues 110 to fold upwards around their respective connecting parts 111 toward the center line of the busbar 100 until the two tongues 110 are completely attached to the upper surface of the upper busbar 100. When the tongue 110 is folded downward, the two busbars 100 can be fixed by a clamping fixture. Then, the two tongues 110 of the same tongue unit can be applied downward by a corresponding folding tool or manual operation, and the two tongues 110 can be folded downward around their respective connecting parts 111 toward the center line of the busbar 100 until the two tongues 110 are completely attached to the lower surface of the lower busbar 100.

[0049] By setting two folding methods, the two folding directions have greater applicability and can be flexibly selected according to production needs. Folding upwards facilitates visual inspection of the adhesion status of the tongue 110, thereby promptly detecting problems such as incomplete folding or loose adhesion of the tongue 110; folding downwards allows the tongue 110 to be hidden under the manifold 100, avoiding accidental scratches or damage to the tongue 110 during subsequent traction and transportation.

[0050] In an optional embodiment of this application, each busbar 100 has a tongue 110 at the edge of each of its two long sides, and the number of tongues 110 is at least three. The tongues 110 at the edges of the two long sides of the busbar 100 are arranged alternately along the length direction of the busbar 100. Folding two tongues 110 of the tongue unit simultaneously around the connecting portion 111 towards the center line of the length direction of the busbar 100 includes: At least one tongue unit has two tongues 110 simultaneously folded upward around the connecting portion 111 toward the center line of the busbar 100 in the length direction, so that the two tongues 110 of the tongue unit are folded to the upper side of the busbar 100; the remaining tongue units have two tongues 110 simultaneously folded downward around the connecting portion 111 toward the center line of the busbar 100 in the length direction, so that the two tongues 110 of the tongue unit are folded to the lower side of the busbar 100.

[0051] In this embodiment, the two tongues 110 of some tongue units are folded upward and the two tongues 110 of some tongue units are folded downward, so that the joint forms a bidirectional mechanical locking structure, which can firmly fix the two busbars 100 along the length direction, strengthen the resistance to deformation, further enhance the structural strength of the joint, avoid the risk of breakage caused by excessive force on one side, and there is no interference between the tongue units with different folding directions.

[0052] In optional embodiments of this application, the shape of the tongue 110 is any one or at least a combination of any two of the following: rectangular, trapezoidal, triangular, M-shaped, circular, semi-circular, elliptical, serrated, and wavy. Figure 10 , 11 A simplified illustration of the different shapes of the tongue 110 described above is provided.

[0053] In this embodiment, the two tongues 110 of the same tongue unit have the same shape, and the shapes of each tongue unit can be the same or different. The diverse shapes of the tongues 110 allow the busbar splicing process to adapt to different stress requirements and production scenarios, improving the flexibility and applicability of the process. Moreover, when the tongue 110 is trapezoidal, the long side of the tongue 110 is the connecting portion 111 connected to the busbar 100, which can enhance the connection strength between the tongue 110 and the busbar 100 body.

[0054] In an optional embodiment of this application, the tongue 110 is trapezoidal in shape, such as... Figure 7 , 8 As shown, when the tongue 110 is trapezoidal, the longer side of the tongue 110 (i.e., the longer side among the upper and lower sides of the trapezoid) is the connecting part 111 that connects to the busbar 100. The trapezoid can be a regular trapezoid, an isosceles trapezoid, or a right trapezoid, and is not limited to the one shown in the figure.

[0055] In an optional embodiment of this application, the tongue unit pressing against the tongue 110 of the busbar 100 is the first tongue, and the area of ​​the busbar in contact with the first tongue 110 is the first area; before folding the two tongues 110 of the tongue unit simultaneously around the connecting portion 111 toward the centerline of the length direction of the busbar 100, the method further includes: Apply adhesive to the surface of the first tongue facing the first region; and / or apply adhesive to the first region.

[0056] In this embodiment, adhesive is applied to at least one location on the first tongue and in the first region before the tongue unit is folded. After application, the tongue 110 is folded and pressed within the effective working time of the adhesive to ensure that the adhesive fully wets both mating surfaces, forming a strong bond. By applying adhesive, a dual fixing effect of mechanical locking and adhesive fixation is achieved, significantly improving the connection strength and stability between the two busbars 100.

[0057] In an optional embodiment of this application, after pressing the folded tongue unit against the busbar 100, the method further includes: The folded tongue unit and busbar 100 are subjected to roller pressing or secondary pressing.

[0058] In this embodiment, after the tongue unit is folded and pressed for the first time, the joint is subjected to roller pressing or secondary pressing. Specifically, the joint of the busbar 100 is placed stably on a workbench, and a roller press drives the rollers to roll at a uniform speed along the length of the busbar 100, thereby applying pressure to the folded tongue unit and the busbar 100 to ensure that the tongue 110 and the surface of the busbar 100 are completely adhered. During the secondary pressing, a pressure head adapted to the joint area is used to apply uniform pressure to the joint through a pressure device, further compacting the contact surface between the tongue 110 and the busbar 100. Moreover, for the above-described embodiment with adhesive coating, this roller pressing or secondary pressing step allows the adhesive to be distributed more evenly, while accelerating the curing process and improving the bonding effect.

[0059] Rolling or secondary pressing can improve the fit between the tongue 110 and the busbar 100, enhancing the tensile strength, shear strength, and vibration resistance of the joint, thus better coping with various external forces during the production and use of photovoltaic modules. Simultaneously, rolling or secondary pressing can correct slight misalignments or warping that may occur during folding, ensuring the flatness of the joint.

[0060] In an optional embodiment of this application, the width of the tongue 110 is w, where 1mm ≤ w ≤ 3mm. The 1-3mm width range of the tongue 110, compared to the 4-6mm width of the busbar 100, ensures sufficient structural strength for the tongue 110 while avoiding insufficient edge allowance for the busbar 100 due to an excessively wide tongue 110. This ensures the performance of the tongue 110 itself while maximizing the structural integrity of the busbar 100 body, making the joint both strong and resistant to breakage.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A busbar splicing process, characterized in that, The busbar splicing process is applied in photovoltaic module production to connect the tail of the previous busbar to the head of the next busbar; wherein: the width of the busbar is 4-6mm; The busbar splicing process includes: The tail region of the previous busbar and the head region of the next busbar are stacked one on top of the other, so that the two busbars form an overlapping area of ​​a predetermined length in the length direction. Within the overlapping area, a tongue is formed at the edge of the long side of each busbar by a stamping or shearing process; wherein: the tongue has a connecting portion connected to the busbar, the tongues on the two busbars correspond one-to-one, and the two corresponding tongues form a tongue unit; The two tongues of the tongue unit are simultaneously folded around the connecting portion toward the center line of the busbar length direction; The folded tongue unit is pressed against the busbar to complete the connection between the tail region of the previous busbar and the head region of the next busbar.

2. The busbar splicing process according to claim 1, characterized in that, The process of fabricating a tongue at the edge of the long side of each busbar within the overlapping area by a stamping or shearing process includes: Within the overlapping area, tongues are formed at the edges of the two long sides of each busbar by a stamping or shearing process, and the tongues located on the two long sides of the busbar are completely offset from each other along the length of the busbar.

3. The busbar splicing process according to claim 2, characterized in that, The number of tongues is at least three, and the tongues on the two long sides of the busbar are arranged alternately along the length of the busbar.

4. The busbar splicing process according to claim 1, characterized in that, At least two tongues are formed on the first long side of the manifold, and at least one tongue is formed on the second long side of the manifold. The distance between the centers of two adjacent tongues on the first long side of the manifold is L1, and the length of the tongue on the second long side of the manifold is L2, wherein: L1 > 2 × L2.

5. The busbar splicing process according to claim 1, characterized in that, The step of simultaneously folding the two tongues of the tongue unit around the connecting portion towards the centerline of the busbar length includes: The two tongues of the tongue unit are simultaneously folded upwards around the connecting portion toward the center line of the manifold length direction, so that the two tongues of the tongue unit are folded to the upper side of the manifold above; Alternatively, the connecting portion may simultaneously fold both tongues of the tongue unit downwards around the connecting portion toward the center line of the manifold length direction, so as to fold the two tongues of the tongue unit to the lower side of the manifold below.

6. The busbar splicing process according to claim 1, characterized in that, Each of the busbars has a tongue at the edge of each of its two long sides, and the number of tongues is at least three. The tongues at the edges of the two long sides of the busbar are staggered sequentially along the length of the busbar. The step of simultaneously folding two tongues of the tongue unit around the connecting portion towards the centerline of the busbar's length direction includes: At least one tongue unit has two tongues simultaneously folded upwards around the connecting portion toward the center line of the manifold length direction, so that the two tongues of the tongue unit are folded to the upper side of the upper manifold; the remaining tongue units have two tongues simultaneously folded downwards around the connecting portion toward the center line of the manifold length direction, so that the two tongues of the tongue unit are folded to the lower side of the lower manifold.

7. The busbar splicing process according to claim 1, characterized in that, The shape of the tongue is any one or at least a combination of two of the following: rectangular, trapezoidal, triangular, M-shaped, circular, semi-circular, elliptical, serrated, and wavy. When the shape of the tongue is trapezoidal, the long side of the tongue is the connecting part that is connected to the busbar.

8. The busbar splicing process according to any one of claims 1 to 7, characterized in that, The tongue unit that presses against the tongue of the busbar is the first tongue, and the area of ​​the busbar that contacts the first tongue is the first area; Before simultaneously folding the two tongues of the tongue unit around the connecting portion towards the centerline of the busbar length, the method further includes: Apply adhesive to the surface of the first tongue facing the first region; And / or, apply an adhesive to the first area.

9. The busbar splicing process according to any one of claims 1 to 7, characterized in that, After pressing the folded tongue unit against the busbar as described in step [1], the method further includes: The folded tongue unit and the busbar are subjected to roller pressing or secondary pressing.

10. The busbar splicing process according to any one of claims 1 to 7, characterized in that, The width of the tongue is w, where 1mm ≤ w ≤ 3mm.

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