Welding device and application thereof
By using a polygonal winding cylinder and a conductive wire positioning and locking mechanism, combined with a vision inspection unit, high-precision alignment and welding of multi-busbar solar cells and conductive wires is achieved, solving the problem of alignment between solar cells and conductive wires in existing technologies and improving welding quality and yield.
Patent Information
- Application Number
- CN202411106332.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-13
- Publication Date
- 2026-02-24
AI Technical Summary
Existing technologies make it difficult to achieve high-precision alignment and welding between multi-busbar solar cells and conductive wires, especially the precise alignment of the 160 current collection layers and conductive wires in stacked busbar solar cells, which makes it difficult to guarantee yield.
A polygonal winding drum is used as the conductive wire alignment system. Combined with a conductive wire positioning and locking mechanism and a vision inspection unit, the conductive wire and the battery cell are precisely aligned and welded by adjusting the XYZθ position.
This improved the welding quality and yield of the conductive wire and the solar cell, ensured the precise alignment of the solar cell and the conductive wire, reduced the deformation of the solar cell during the alignment process, and improved welding efficiency and precision.
Smart Images
Figure CN121551729A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of photovoltaic technology, specifically to a welding device and its application. Background Technology
[0002] Multi-busbar (MBB) solar cells generally refer to solar cells with more than 10 busbars. MBB cells can reduce electrical losses and improve optical efficiency. With the increasing size of solar cells, MBB cells have become the mainstream technology in the industry. OBB cells eliminate the main busbars, primarily using solder ribbons to conduct current, thus eliminating the need for screen printing of the main busbars. This significantly reduces silver paste usage, saves costs, and simplifies the cell manufacturing process. The absence of main busbars also reduces light shading, increasing module optical gain and power output. The latest tandem grid cells optimize the pattern structure, eliminating the traditional main and sub-busbars and replacing them with a single, parallel current collection layer. Current is directly drawn from inside the cell and transferred to conductive filaments. This process requires efficient and precise alignment and soldering of the conductive filaments with the current collection layer of the tandem grid cell.
[0003] Stacked-grid solar cells have a large number of current-collecting layers; for example, an 182-grid solar cell has nearly 160 current-collecting layers, requiring 160 conductive wires for alignment and welding. One method (publication number 115483314A) involves adsorbing two or more solar cells onto a roller, then winding conductive wires around the roller to align the wires with the current-collecting layers of the solar cells. This method requires multiple solar cells to be placed in designated positions on the roller, demanding extremely high precision. Furthermore, the winding accuracy must also be very high to achieve accurate alignment, making it difficult to guarantee a high yield rate. Summary of the Invention
[0004] The purpose of this invention is to provide a welding device that utilizes a polygonal winding bobbin as a conductive wire alignment system to achieve precise alignment between the conductive wire and the welding position on the workpiece.
[0005] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a welding apparatus, including a conductive wire alignment system. The conductive wire alignment system includes a workpiece fixing platform and a polygonal winding cylinder. The workpiece fixing platform receives and fixes a battery cell to be wired, and then moves it to a laying position. The polygonal winding cylinder is located above the laying position. The polygonal winding cylinder includes a plate-shaped base, on which multiple winding posts are arranged. The lines connecting the multiple winding posts form a polygon. The outer surface of the polygon forms a winding surface, and the winding surface between every two winding posts forms a welding surface. Each winding post has a winding position corresponding to the welding position on the workpiece, and the winding position has a conductive wire positioning and locking mechanism.
[0006] Preferably, among the multiple winding posts, every two adjacent winding posts are connected and fixed by a connecting rod.
[0007] Preferably, the conductive wire positioning and locking mechanism is a V-shaped groove opened on the winding position of the winding post.
[0008] Preferably, one or more wire clamps are provided on the plate-shaped base.
[0009] Preferably, the workpiece fixing platform uses an adsorption method to fix the workpiece to be processed.
[0010] Preferably, the workpiece fixing platform is installed on the displacement platform, and the workpiece to be processed is fixed on the workpiece fixing platform and moved to the layout station by the displacement platform.
[0011] More preferably, at least two sets of workpiece fixing platforms are installed on the displacement platform, wherein when the displacement platform moves one set of workpiece fixing platforms to the layout station, at least one set of the other workpiece fixing platforms is in the pre-installation station.
[0012] Furthermore, the displacement platform is a rotating platform, with the placement station and the pre-assembly station located on opposite sides of the rotating platform, and a wafer feeder is located above the pre-assembly station.
[0013] Preferably, it further includes a vision inspection unit, which detects the alignment between the workpiece to be processed on the workpiece fixing platform and the conductive wire.
[0014] In a second aspect, the present invention further discloses a welding method using the welding apparatus described above, comprising: winding a conductive wire on a winding drum, fixing the workpiece to be processed on a fixed platform and moving it to a placement station, aligning the workpiece to be processed on the fixed platform with the conductive wire on the welding surface of the winding drum, bringing the part of the workpiece to be welded into contact with the conductive wire on the welding surface, and using solder to weld the part to be welded to the conductive wire.
[0015] In a preferred embodiment, the solder is pre-coated on the contact surface of the conductive wire, and the welding method includes heating and welding after bringing the part to be welded of the workpiece into contact with the conductive wire on the welding surface.
[0016] Furthermore, the pre-coating of solder on the contact surface of the conductive wire is completed either before winding or after winding onto the winding bobbin and before contact with the welding area of the workpiece.
[0017] When the pre-coating is completed after winding, the coating includes first applying flux or solder paste to the contact surface of the conductive wire, and then applying solder.
[0018] In the welding method described above, the coating method is preferably spraying.
[0019] In another preferred embodiment, the solder is pre-coated onto the surface of the workpiece to be welded.
[0020] In the welding method described above, it is more preferable to include a reinforcement step of applying adhesive after welding.
[0021] Compared with existing technologies, the advantages of this invention are as follows: Unlike existing welding alignment mechanisms, the welding surface is formed by the winding surfaces between the winding columns using a polygonal winding drum. The battery cell does not need to be directly adsorbed onto the winding drum. The winding and battery cell adsorption processes are completed independently before welding, followed by alignment welding. Therefore, there is sufficient adjustment space between the battery cell and the conductive wire before welding. Furthermore, the welding surface is planar, avoiding deformation of the battery cell before alignment. The battery cell can be easily aligned with the conductive wire, thus ensuring the welding quality of the conductive wire in the stacked grid battery cell. The conductive wire positioning and locking mechanism ensures the positioning accuracy of the conductive wire, especially in the case of V-grooves, which can automatically correct the positional deviation of the conductive wire during winding. The battery cell is fed to the bottom of the winding drum by a moving platform, which can perform XYZθ position adjustment. The position of the battery cell's current collection layer is aligned with the pre-fabricated conductive wire position on the winding drum using a vision camera. The adsorption platform rises to bring the conductive wire into close contact with the battery cell. Infrared, hot air, or other heating methods are used to heat the battery cell to the welding temperature to complete the welding. Attached Figure Description
[0022] Figure 1 A schematic diagram of the conductive wire welding device for stacked grid solar cells of the present invention; Figure 2 This is a schematic diagram of the polygonal winding cylinder and its rotating base in the conductive wire alignment system. Figure 3 This is a schematic diagram of the winding post, showing the V-shaped groove on top.
[0023] In the diagram: 1. Winding drum; 2. Base; 3. Winding post; 4. Connecting rod; 5. Adsorption platform; 6. Layout station; 7. Pre-assembly station; 8. Displacement platform; 9. Feeder; 10. Wire clamp; 11. Wire guide wheel; 12. Rotating base; 13. V-groove. Detailed Implementation
[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0025] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for 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. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0026] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0027] See Figure 1 The present invention uses multiple winding posts 3 to form a polygonal winding cylinder 1, and a conductive wire is wound around the polygonal winding cylinder at equal intervals by winding, thereby realizing the prefabrication of multiple conductive wires.
[0028] like Figure 2 As shown, the winding cylinder 1 is composed of multiple winding posts 3. After the conductive wire is wound on the winding posts, it forms a polygonal structure. The length of each side of the polygon is the distance between two winding posts. Therefore, the surface between the two winding posts forms a welding surface. This welding surface is large enough to accommodate a battery cell. That is, the distance between the two winding posts is large enough to accommodate the length or width of a battery cell, depending on the orientation of the battery cell.
[0029] like Figure 3 As shown, V-grooves 13 with equal spacing are formed on the winding column constituting the winding bobbin. The opening width of the V-grooves is greater than the width of the conductive wire. During the winding process, the V-grooves can automatically correct the positional deviation of the conductive wire, with a tolerance accuracy of the difference between the opening width of the V-grooves and the width of the conductive wire. Multiple conductive wires with high precision and equal spacing can be pre-fabricated using a winding bobbin with V-grooves for positioning. Using a winding bobbin with V-grooves can improve winding accuracy, similar to the template method, which can pre-fabricate multiple conductive wires with equal spacing, ensuring reliable accuracy in the spacing between the conductive wires.
[0030] Below the winding drum 1 is a battery cell adsorption platform 5 for positioning. The platform can be adjusted in XYZθ position. The position of the battery cell current collection layer is aligned with the position of the pre-fabricated conductive wire on the winding drum by a vision camera. The adsorption platform rises to make the conductive wire and battery cell come into close contact. Infrared, hot air or other heating methods are used to heat the battery cell to the welding temperature to complete the welding.
[0031] For different welding methods, there are different solutions when using different conductive wires, as described below: 1. When the conductive wire used is a triangular conductive wire with solder on the surface, it is first wound on a roller. A plane composed of conductive wires with equal spacing will be formed between two winding posts. Then the battery cell is sent to the laying position by the feeding mechanism, i.e. the adsorption platform. Here, the battery cell is aligned with the conductive wire plane. The platform rises and contacts the conductive wire, and heats and welds it to obtain a battery cell with the conductive wire welded on. Then, as needed, glue is applied for welding reinforcement and fixation. 2. When using conductive wires without soldering material on the surface, first wind the wires onto a roller. A plane composed of evenly spaced conductive wires will be formed between the two winding posts. Then, apply solder paste / conductive adhesive to this conductive wire plane, or first apply flux / solder paste to the conductive wire plane, and then spray solder powder of appropriate particle size onto it. The side of the conductive wire with flux or solder paste will be covered with solder powder. Then, the battery cell is sent to the laying position by the feeding mechanism, i.e., the adsorption platform. Here, the battery cell is aligned with the conductive wire plane, the platform rises and contacts the conductive wire, and heats and solders it to obtain a battery cell with soldered conductive wires. 3. When the conductive wire used is a conductive wire without soldering material on its surface, it is first wound on a roller. A plane composed of conductive wires arranged at equal intervals will be formed between two winding posts. Solder paste / conductive adhesive is applied to the grid line part of the cell surface, or tin is pre-coated on the grid line of the cell through electroplating or other methods. Then the cell is sent to the laying station by the feeding mechanism, i.e., the adsorption platform. Here, the cell is aligned with the conductive wire plane, the platform rises and contacts the conductive wire, and heats and solders it to obtain a cell with soldered conductive wire.
[0032] After a solar cell is welded, the adsorption platform 5 releases its grip on the cell. The cell adheres to the winding drum using the welding force between itself and the conductive wire, and moves away from the placement station as the drum rotates. The next surface of the winding drum to be welded rotates above the placement station, ready for the next solar cell to be welded. Once all surfaces of the winding drum to be welded are completed, the drum is moved to the cutting station to cut the conductive wire, thus separating the solar cell from the winding drum. The conductive wire can be cut individually to form individual solar cells, or it can be cut at intervals or in other ways to form a battery string. The specific cutting method depends on the circuit design of the solar cell.
[0033] During conductive wire welding, multiple conductive wires are pre-fabricated by winding the bobbin 1. The battery cells are fixed on the adsorption platform, and the position of the battery cells is adjusted with visual assistance for alignment before welding. The pre-fabrication of the conductive wires on the bobbin can be completed on-site on the welding device, such as... Figure 1 As shown, the conductive wire is fed to the winding drum 1 via the guide wheel 11, as... Figure 2 As shown, the end of the conductive wire is fixed on the wire clamp 10 on the base 2. Then, the winding drum 1 rotates rapidly through the rotating base 12 connected to the base 2 to quickly complete the prefabrication of the conductive wire on the winding drum 1. Since the winding speed is relatively fast, the welding speed often cannot keep up with the prefabrication speed of the winding drum. Therefore, in another embodiment, the winding drum can be prefabricated and then clamped onto the rotating base.
[0034] The individual cells are delivered to the placement station directly below the winding drum via the adsorption platform 5, where they are then visually aligned to achieve extremely high yield. Alternatively, the cells can be pre-installed on the adsorption platform at a pre-assembly station, outside of the placement station. In a preferred embodiment, the cells can be transported as follows: Figure 1 As shown, the solar cell adsorption platform 5 is transported between the placement station 6 and the pre-assembly station 7 via a disc-shaped displacement platform 8. Above the pre-assembly station, there is also a cell feeder 9, which adsorbs and fixes the solar cells when the adsorption platform 5 is transported to the pre-assembly station.
[0035] Of course, the displacement platform can also be used in other ways, such as a conveyor belt, for the translation and transfer of the adsorption platform 5. Therefore, the specific embodiments shown in the above examples and accompanying drawings should not limit the scope of protection of this invention. All improvements made by those skilled in the art after understanding the principles of this invention without departing from the basic principles of this invention are still within the scope of protection of this invention.
[0036] Furthermore, it should be understood that although the welding apparatus of the present invention is described using a battery cell as an example in the embodiments of the specification, those skilled in the art can easily understand through the technical principles of the present invention that the apparatus of the present invention can be used for alignment welding of conductive wires and sheet-like weldments, and has excellent alignment welding efficiency and effect. The sheet-like weldments mentioned above include, for example, semiconductor devices.
[0037] Furthermore, the term "welding" mentioned in the text can be understood as a connection method and should be interpreted broadly. That is, welding is a process in which two or more similar or dissimilar materials are connected into one through the bonding and diffusion between atoms or molecules. Therefore, materials other than solder should also be included within the scope of protection of this invention. For example, in the solution of this invention, the connection between the conductive wire and the workpiece can be made not only with solder but also with conductive adhesive. Therefore, conductive adhesive should also be included within the scope of the term "solder". Similarly, materials with similar connection properties should also be included within the scope of protection of this invention.
[0038] Any aspects of this invention not described in detail are well-known to those skilled in the art.
[0039] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications and equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.
Claims
1. A welding apparatus, comprising a conductive wire alignment system, characterized in that, The conductive wire alignment system includes a workpiece fixing platform and a polygonal winding drum. The workpiece fixing platform receives and fixes the workpiece to be processed and then moves it to the placement station. The polygonal winding drum is located above the placement station. The polygonal winding drum includes a plate-shaped base with multiple winding posts on the base. The lines connecting the multiple winding posts form a polygon. The outer surface of the polygon forms a winding surface, and the winding surface between every two winding posts forms a welding surface. Each winding post has a winding position corresponding to the welding position on the workpiece to be processed, and the winding position has a conductive wire positioning and locking mechanism.
2. The welding apparatus as described in claim 1, characterized in that, Among the multiple winding posts, every two adjacent winding posts are connected and fixed by a connecting rod.
3. The welding apparatus as described in claim 1, characterized in that, The conductive wire positioning and locking mechanism is a V-shaped groove opened on the winding position of the winding post.
4. The welding apparatus as described in claim 1, characterized in that, One or more wire clamps are provided on the plate-shaped base.
5. The welding apparatus as described in claim 1, characterized in that, The workpiece fixing platform uses an adsorption method to fix the workpiece to be processed.
6. The welding apparatus as described in claim 1, characterized in that, The workpiece fixing platform is installed on the displacement platform. The workpiece to be processed is fixed on the workpiece fixing platform and moved to the layout station by the displacement platform.
7. The welding apparatus as described in claim 6, characterized in that, The displacement platform is equipped with at least two sets of workpiece fixing platforms. When the displacement platform moves one set of workpiece fixing platforms to the layout station, at least one set of the other workpiece fixing platforms is in the pre-installation station.
8. The welding apparatus as described in claim 7, characterized in that, The displacement platform is a rotating platform, with the placement station and the pre-assembly station located on opposite sides of the rotating platform. A wafer feeder is also located above the pre-assembly station.
9. The welding apparatus as claimed in claim 1, characterized in that, It also includes a vision inspection unit, which detects the alignment between the workpiece to be processed and the conductive wire on the workpiece fixing platform.
10. A welding method using the welding apparatus as described in any one of claims 1 to 9, characterized in that, The method includes: winding a conductive wire on a bobbin, fixing the workpiece to be processed on a fixed platform and moving it to a layout station, aligning the workpiece to be processed on the fixed platform with the conductive wire on the welding surface of the bobbin, making the part to be welded on the workpiece contact the conductive wire on the welding surface, and using solder to weld the part to be welded to the conductive wire.
11. The welding method as described in claim 10, characterized in that, The solder is pre-coated on the contact surface of the conductive wire, and the welding method includes heating and welding after bringing the part to be welded of the workpiece into contact with the conductive wire on the welding surface.
12. The welding method as described in claim 11, characterized in that, The pre-coating of solder on the contact surface of the conductive wire is completed either before winding or after winding onto the bobbin and before contact with the part to be welded on the workpiece.
13. The welding method as described in claim 12, characterized in that, When the pre-coating is done after winding, the coating includes first applying flux or solder paste to the contact surfaces of the conductive wire, and then applying solder.
14. The welding method as described in claim 13, characterized in that, The coating method is spraying.
15. The welding method as described in claim 10, characterized in that, The solder is pre-coated onto the surface of the workpiece to be welded.
16. The welding method according to any one of claims 10 to 15, characterized in that, After welding, a reinforcement step involving applying adhesive is also included.