Solar cell single-piece welding device and welding method

Abstract

The invention provides a solar cell single-piece welding device and a welding method thereof.The device comprises a rack, and a welding strip feeding mechanism, a welding strip processing mechanism, a welding strip traction mechanism, a cell welding mechanism and a cell detection mechanism are sequentially arranged at the inlet end of the rack inwards; the welding strip traction mechanism comprises a first welding strip wire drawing mechanism arranged at the near end of the discharging end of the welding strip processing mechanism and a second welding strip wire drawing mechanism arranged at the far end of the discharging end of the welding strip processing mechanism, and the first welding strip wire drawing mechanism and the second welding strip wire drawing mechanism move in the welding strip extending direction and the vertical direction. The opening end of a wire drawing clamping jaw of the second welding strip wire drawing mechanism is parallel to the extending direction of the axis of the welding strip. The invention has the beneficial effects that different requirements can be realized as required, namely, the welding of the positive and negative electrodes of the single battery piece and the welding strip can be realized, and the series welding of the battery pieces can also be realized. When the anode and the cathode of a single battery piece are welded with a welding strip, the battery string can be further matched for repair.

Description

Technical Field

[0001] The present invention belongs to the technical field of photovoltaic components, and in particular relates to a single-piece solar cell welding device and a welding method thereof. Background Art

[0002] With the widespread use of solar energy, the solar photovoltaic panel industry has also flourished. During solar panel production, multiple cells and ribbons are welded together into cell strings using a stringing machine. Cell stringing involves welding multiple cells together in a specific order and direction to form a series circuit. This interconnection allows current to flow from one cell to another, forming a complete panel. Before being put into practical use, the cell strings must be inspected. If any defective cells are present in the string, the corresponding cells must be removed and replaced.

[0003] When stringing cells and ribbons, the current string welding machines on the market first use the ribbon pulling mechanism to pull or tighten the processed ribbon, and then weld it to the cell. Due to the structural limitations of the ribbon pulling mechanism, it is only possible to weld two adjacent cells first, and then achieve string welding connections between multiple cells. The structure of the battery string after string welding is single, and it is impossible to complete the welding between the positive and negative electrodes of a single cell and the ribbon. This means that if a single cell is required, additional mechanisms and means are required to cut and obtain the battery string. This makes the entire process more cumbersome, and it is also impossible to cooperate well with the battery string inspection and replacement equipment to realize the automation of cell repair. Summary of the Invention

[0004] In order to solve the deficiencies of the prior art, the present invention provides a solar cell single-piece welding device and a welding method thereof.

[0005] The purpose of the present invention is achieved through the following technical solutions: A single-piece solar cell welding device includes a frame, wherein a welding ribbon feeding mechanism, a welding ribbon processing mechanism, a welding ribbon pulling mechanism, a cell welding mechanism, and a cell detection mechanism are sequentially arranged inward from the inlet end of the frame, and the welding ribbon pulling mechanism includes a first welding ribbon wire pulling mechanism disposed proximal to the discharge end of the welding ribbon processing mechanism and a second welding ribbon wire pulling mechanism disposed distal to the discharge end of the welding ribbon processing mechanism. The first welding ribbon wire pulling mechanism and the second welding ribbon wire pulling mechanism move in the extension direction and the vertical direction of the welding ribbon, and the opening end of the wire pulling jaw of the second welding ribbon wire pulling mechanism is parallel to the extension direction of the welding ribbon axis.

[0006] Preferably, the wire pulling claw of the second welding ribbon pulling mechanism has an L-shaped cross section.

[0007] Preferably, the first welding ribbon wire pulling mechanism and the second welding ribbon wire pulling mechanism are respectively arranged on both sides of the welding ribbon, and each includes a horizontal moving mechanism arranged on the outside of the welding ribbon, and a lifting mechanism is vertically arranged on the horizontal moving mechanism, and the lifting mechanism is provided with a clamping arm, and the lower end of the clamping arm is provided with a wire pulling clamp, and the clamping arm extends from the outside to the inside of the welding ribbon; the setting direction of the horizontal moving mechanism is consistent with the transmission direction of the welding ribbon.

[0008] Preferably, the wire pulling claw of the first welding ribbon wire pulling mechanism is a first wire pulling claw, the open end of the first wire pulling claw is vertically downward, and the wire pulling claw of the second welding ribbon wire pulling mechanism is a second wire pulling claw, the second wire pulling claw is L-shaped, and its open end is facing the welding ribbon.

[0009] Preferably, a welding light box is provided above the cell welding mechanism, and the upper part of the welding light box is connected to the upper and lower cylinders. When the upper and lower cylinders work, the welding light box is driven to cover the cell welding mechanism.

[0010] Preferably, the cell detection mechanism includes an image acquisition camera arranged above the rack.

[0011] Preferably, the string welding device also includes a material grabbing mechanism, which includes upper and lower material grabbing cylinders and a tooling suction plate placed at the lower ends of the upper and lower material grabbing cylinders. The end of the tooling suction plate is provided with an electromagnetic end head. The upper and lower material grabbing cylinders are connected to the upper and lower linear motors through a connecting plate. A suction plate is connected under the connecting plate, and a vacuum suction cup for adsorbing battery cells is provided at the bottom of the suction plate.

[0012] Preferably, the distance between the electromagnetic ends at both ends of the tooling suction plate is greater than the length of the suction plate.

[0013] Preferably, a welding ribbon pressing mechanism is provided on one side of the material grabbing mechanism, and the welding ribbon pressing mechanism includes a pressing plate and independent pressing pins evenly distributed on the bottom of the pressing plate.

[0014] Preferably, the above-mentioned welding method of the solar cell single-piece welding device is characterized by comprising the following steps: S1, the welding ribbon enters the welding ribbon processing mechanism from the welding ribbon feeding mechanism for routine processing and then enters the welding ribbon traction mechanism of the conveying platform; S2. The wire clamps of the first and second welding ribbon pulling mechanisms respectively pull and tighten the ends of the welding ribbon, and then the cutter on the welding ribbon processing mechanism cuts the welding ribbon. At this time, the first and second welding ribbon pulling mechanisms are kept tightening the ends of the welding ribbon. S3: The gripping mechanism places the grabbed single cell on the solder ribbon. The bottom solder ribbon and the cell are fixed in position by the adsorption assembly under the conveying platform. The first and second solder ribbon pulling mechanisms release the pulling claws to complete the pulling of the bottom solder ribbon of the cell. S4. The first and second wire-pulling jaws will continue to pull the upper layer of the solar cell's welding ribbon through the lifting mechanism of the welding ribbon pulling mechanism, and place the upper layer of the welding ribbon above the solar cell; S5. The gripping mechanism places the gripped cell onto the upper soldering ribbon of the single cell and presses it tightly. S6. The conveying platform transports the compressed welding ribbon and the single cell to the welding station for welding through the cell welding mechanism. During welding, the welding light box can further ensure that the welding heat is not lost and improve the welding quality; S7. After welding is completed, the gripping mechanism grabs and removes the battery cell tooling, and the welded single battery cell enters the inspection station, and the pressure pins of the inspection pressure pin assembly on one side of the gripping mechanism apply current and voltage to both ends of the single battery cell, and the inspection camera takes a picture of it for EL inspection.

[0015] The beneficial effects of the present invention are reflected in its ability to meet different needs as needed, namely, it can achieve welding of the positive and negative electrodes of a single battery cell to the welding ribbon, and it can also achieve string welding of battery cells. When welding the positive and negative electrodes of a single battery cell to the welding ribbon, it can be further combined with battery string repair equipment to achieve an integrated operation, providing a favorable foundation for improving the automated repair of battery strings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 : The structural representation of the present invention.

[0017] Figure 2 : Schematic diagram of the structure of the first welding ribbon pulling mechanism in the present invention.

[0018] Figure 3 : Schematic diagram of the structure of the second welding ribbon pulling mechanism in the present invention.

[0019] Figure 4 : Schematic diagram of the structure of the battery cell grabbing mechanism in the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present invention more clear, the following Figure 1-Figure 4 It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] The present invention discloses a device for welding single solar cell wafers. The string welding device includes a frame, a conveying platform is provided inside the frame, and a welding ribbon feeding mechanism 1, a welding ribbon processing mechanism, a welding ribbon pulling mechanism 2, a cell welding mechanism 4, and a cell detection mechanism 6 are sequentially provided inward from the entrance end of the frame. The welding ribbon feeding mechanism 1 is used to include a material roller and a welding ribbon placed on the material roller. The welding ribbon enters the welding ribbon processing mechanism for processing. Generally, the processing of the welding ribbon includes soaking the welding ribbon in flux, pressing it, flattening it, and then, after the welding ribbon is pulled and stretched to the desired position by the welding ribbon pulling mechanism 2, the welding ribbon is cut at the tail end by a cutter. A transfer line is provided above the conveying platform, and a material grabbing mechanism is provided on the transfer line. The material grabbing mechanism is used to grab the cell or cell tooling and cooperate with other mechanisms to complete the welding process of a single cell wafer.

[0022] The ribbon pulling mechanism 2 of the present invention includes a first ribbon wire pulling mechanism positioned proximal to the discharge end of the ribbon processing mechanism and a second ribbon wire pulling mechanism positioned distal to the discharge end of the ribbon processing mechanism. The ribbon pulling mechanism 2 includes a movable mechanism and wire pulling clamps, the number of which corresponds to the number of ribbons. For those skilled in the art, in this embodiment, the ribbon pulled by the first ribbon wire pulling mechanism is the tail end of the ribbon, while the ribbon pulled by the second ribbon wire pulling mechanism is the head end of the ribbon. Both ribbon wire pulling mechanisms are movable, meaning they can achieve horizontal and vertical displacement of the wire pulling clamps.

[0023] The first and second ribbon pulling mechanisms have essentially the same moving structure, comprising a lateral moving mechanism positioned outside the ribbon and a lifting mechanism positioned perpendicularly above the lateral moving mechanism. The lifting mechanism is provided with a clamping arm 23, each with a wire pulling jaw at its lower end. The lateral moving mechanism is positioned in the same direction as the ribbon is transported.

[0024] In this embodiment, the wire pulling jaw of the first welding ribbon pulling mechanism is the first wire pulling jaw 24. The opening end of the first wire pulling jaw 24 is vertically downward and perpendicular to the welding ribbon axis. Of course, the structure of the first wire pulling jaw 24 can also be other forms.

[0025] The wire pulling jaw of the second welding ribbon wire pulling mechanism is the second wire pulling jaw 27. The second wire pulling jaw 27 is arranged in an L shape, and its jaw opening end is parallel to the extension direction of the welding ribbon axis. Furthermore, the opening end of the second wire pulling jaw 27 is arranged facing the welding ribbon discharge end.

[0026] Specifically, the lateral movement mechanism is a transverse linear screw module 21, on which a lifting mechanism is vertically mounted through a base plate. The lifting mechanism includes a back plate 22, with a screw 26 vertically mounted in the middle of the inner side of the back plate. A set of guide rails are provided on both sides of the screw. The bottom of the screw 26 is connected to a drive motor 25 on one side via a pulley. The clamping arm 23 is connected to the screw via a clamping plate. The drive motor 25 rotates the screw, thereby driving the clamping arm 23 to move up and down on the screw. The operation of the transverse linear screw module 21 can drive the clamping arm 23 to move horizontally and upward.

[0027] The movable solder ribbon pulling mechanism of the present invention cooperates with two different structures of clamps, which can realize the requirement of placing the pulled solder ribbon at different positions on the single-chip battery cell. The different positions include realizing the solder ribbon on both sides of the positive and negative poles of the single-chip battery cell, or realizing it at different positions on the same side of the single-chip battery cell. For example, for the conventional case, that is, the two ends of the solder ribbon extend out of the battery cell, the solder ribbon can be directly pulled to the outside of the battery cell by the first pulling clamp and the second pulling clamp. If it is necessary to realize that one end of the solder ribbon is retracted into the battery cell, the second pulling clamp 27 can be used. Since the second pulling clamp 27 is L-shaped, that is, when the second pulling clamp 27 clamps the solder ribbon and pulls it horizontally, when the solder ribbon is located at the required position inside the battery cell, the clamp is released.

[0028] After the relationship between the battery cell and the welding ribbon is positioned, the assembly is transported to the welding station by the conveying platform, and the battery cell welding mechanism completes the direct welding connection between the welding ribbon and the battery cell. In order to better ensure the welding quality and avoid heat loss during welding, a welding light box is provided above the battery cell welding mechanism 4. The upper part of the welding light box is connected to the upper and lower cylinders. When the upper and lower cylinders work, they drive the welding light box to cover the entire battery cell welding mechanism, so that the battery cell welding mechanism can be welded in the welding light box. When the welding is completed, the upper and lower cylinders drive the welding light box to move upward.

[0029] The welded product is then transported by a transmission line to the cell inspection mechanism for inspection. The cell inspection mechanism 6 includes an image acquisition camera installed above the frame. The image of the welded product is captured and fed back to the inspection component for inspection, usually including whether there are any defects such as poor solder joints or defective cells.

[0030] The present invention also includes a gripping mechanism, one side of which is provided with a detection pressure needle assembly for assisting in EL detection of the battery cell. The two are combined on both sides of the bracket and can be used selectively as needed, which can better save space.

[0031] The gripping mechanism not only grasps the battery cells but also the battery cell fixture. It includes upper and lower linear motors 34, each equipped with a connecting plate that moves up and down on the motors. A gripping cylinder 34 is mounted on one upper end of the connecting plate. The cylinder shaft of the gripping cylinder 34 is connected to a fixture suction plate 31. Electromagnetic terminals 32 are attached to the bottom surfaces of both ends of the fixture gripping plate 31, which can hold the battery cell fixture. A suction plate 33 is attached below the connecting plate. The bottom of the suction plate 33 is equipped with a vacuum cup for holding the battery cells. The distance between the electromagnetic terminals at both ends of the fixture suction plate is greater than the length of the suction plate 33, meaning that the suction plate 33 is positioned between the two battery terminals. Controlling the suction plate or the fixture suction plate allows for suction of the battery cell fixture or the battery cell. This is accomplished by combining the transfer line (not shown in this invention) with the corresponding transfer process.

[0032] The detection pressure needle assembly includes upper and lower pressing linear motors arranged on a bracket, and the upper and lower pressing linear motors are connected to a pressure plate. Independent pressure needles are distributed on the bottom of the pressure plate. When performing EL testing, the pressure needles will be used to apply current and voltage to the two ends of the single-chip battery cell.

[0033] The present invention also discloses a welding method for welding a single cell using the above welding device. To better understand the welding principle of the present invention, the following describes the welding process of a single cell and a welding ribbon: The solder ribbon enters the solder ribbon processing mechanism from the solder ribbon feeding mechanism 1 for routine processing. It then enters the solder ribbon traction mechanism 2 on the conveyor platform. The first and second solder ribbon pulling mechanisms respectively pull and tighten the ends of the solder ribbon, and the cutter on the solder ribbon processing mechanism then cuts the ribbon. At this point, the first and second solder ribbon pulling mechanisms continue to tighten the ends of the solder ribbon. The gripping mechanism places the captured single cell onto the solder ribbon using the vacuum suction cup on the suction plate 33. The bottom solder ribbon and cell are held in place by a suction assembly under the conveyor platform. The first and second solder ribbon pulling mechanisms release their grippers, completing the pulling of the bottom solder ribbon on the cell.

[0034] The first and second wire-pulling jaws continue to pull the upper ribbon of the cell through the lifting mechanism of the ribbon pulling mechanism, placing the upper ribbon above the cell. The ribbon pulling and cutting process is the same as the bottom ribbon.

[0035] Furthermore, due to the L-shaped structure of the second wire-pulling jaw, the bottom ribbon can be retracted into the cell when pulling the wire. Of course, the structure of the present invention can also complete the string welding between adjacent cells in existing stringing machines. This can be easily achieved by adjusting the height of the first and second wire-pulling jaws. The string welding principle is the same as that of existing string welding machines.

[0036] The gripping mechanism, using the electromagnetic tip of the gripping plate 31, clamps the gripped cell above the upper solder ribbon of a single cell. The conveyor platform transports the clamped solder ribbon and cell to the welding station, where they are welded by the cell welding mechanism 4. During welding, a welding light box further ensures heat loss, improving weld quality.

[0037] After welding is completed, the gripping mechanism grabs and removes the battery cell tooling, and the welded single battery cell enters the inspection station. The pressure pin of the detection pressure pin assembly on one side of the gripping mechanism applies current and voltage to both ends of the single battery cell, and the detection camera takes a picture of it for EL detection.

[0038] Finally, it should be noted that the conveyor platform (conveyor line), ribbon feeding mechanism, and ribbon handling mechanism described herein are similar to those in conventional stringer machines and are not the primary focus of this invention, so they will not be described in detail here. Terms such as "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" used herein to indicate positions or locations are based on those shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

[0039] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. Solar cell single-piece welding device, characterized by: The machine comprises a frame, on which a welding ribbon feeding mechanism, a welding ribbon processing mechanism, a welding ribbon pulling mechanism, a battery cell welding mechanism and a battery cell detection mechanism are sequentially arranged inward from the inlet end of the frame. The welding ribbon pulling mechanism comprises a first welding ribbon wire pulling mechanism disposed at the proximal end of the welding ribbon processing mechanism discharge end and a second welding ribbon wire pulling mechanism disposed at the distal end of the welding ribbon processing mechanism discharge end. The first welding ribbon wire pulling mechanism and the second welding ribbon wire pulling mechanism move in the welding ribbon extension direction and the vertical direction. The opening end of the wire pulling claw of the second welding ribbon wire pulling mechanism is parallel to the extension direction of the welding ribbon axis.

2. The solar cell single-piece welding device according to claim 1, characterized in that: The cross section of the wire pulling claw of the second welding ribbon wire pulling mechanism is L-shaped.

3. The solar cell single-piece welding device according to claim 1, characterized in that: The first welding ribbon wire pulling mechanism and the second welding ribbon wire pulling mechanism are respectively arranged on both sides of the welding ribbon, and each includes a horizontal moving mechanism arranged on the outside of the welding ribbon, and a lifting mechanism is vertically arranged on the horizontal moving mechanism, and the lifting mechanism is provided with a clamping arm, and the lower end of the clamping arm is provided with a wire pulling clamp, and the clamping arm extends from the outside to the inside of the welding ribbon; the setting direction of the horizontal moving mechanism is consistent with the transmission direction of the welding ribbon.

4. The solar cell single-piece welding device according to claim 2, characterized in that: The wire pulling claw of the first welding ribbon wire pulling mechanism is a first wire pulling claw, and the open end of the first wire pulling claw is vertically downward. The wire pulling claw of the second welding ribbon wire pulling mechanism is a second wire pulling claw, and the second wire pulling claw is L-shaped, with its open end facing the welding ribbon.

5. The solar cell single-piece welding device according to claim 2, characterized in that: A welding light box is provided above the cell welding mechanism. The upper part of the welding light box is connected to the upper and lower cylinders. When the upper and lower cylinders work, they drive the welding light box to cover the cell welding mechanism.

6. The solar cell single-piece welding device according to claim 4, characterized in that: The battery cell detection mechanism includes an image acquisition camera arranged above the frame.

7. The solar cell single-piece welding device according to claim 5, characterized in that: The string welding device also includes a material grabbing mechanism, which includes upper and lower material grabbing cylinders and a tooling suction plate placed at the lower ends of the upper and lower material grabbing cylinders. The end of the tooling suction plate is provided with an electromagnetic end head. The upper and lower material grabbing cylinders are connected to the upper and lower linear motors through a connecting plate. A suction plate is connected below the connecting plate, and a vacuum suction cup for adsorbing battery cells is provided at the bottom of the suction plate.

8. The solar cell single-piece welding device according to claim 6, characterized in that: The distance between the electromagnetic ends at both ends of the tooling suction plate is greater than the length of the suction plate.

9. The solar cell single-piece welding device according to claim 7, characterized in that: A welding ribbon pressing mechanism is provided on one side of the material grabbing mechanism. The welding ribbon pressing mechanism includes a pressing plate and independent pressing pins evenly distributed on the bottom of the pressing plate.

10. The welding method of a solar cell single-piece welding device according to any one of claims 1 to 9, characterized in that: The steps include: S1, the welding ribbon enters the welding ribbon processing mechanism from the welding ribbon feeding mechanism for routine processing and then enters the welding ribbon traction mechanism of the conveying platform; S2. The wire clamps of the first and second welding ribbon pulling mechanisms respectively pull and tighten the ends of the welding ribbon, and then the cutter on the welding ribbon processing mechanism cuts the welding ribbon. At this time, the first and second welding ribbon pulling mechanisms are kept tightening the ends of the welding ribbon. S3: The gripping mechanism places the grabbed single cell on the solder ribbon. The bottom solder ribbon and the cell are fixed in position by the adsorption assembly under the conveying platform. The first and second solder ribbon pulling mechanisms release the pulling claws to complete the pulling of the bottom solder ribbon of the cell. S4. The first and second wire-pulling jaws will continue to pull the upper layer of the solar cell's welding ribbon through the lifting mechanism of the welding ribbon pulling mechanism, and place the upper layer of the welding ribbon above the solar cell; S5. The gripping mechanism places the gripped cell onto the upper soldering ribbon of the single cell and presses it tightly. S6. The conveying platform transports the compressed welding ribbon and the single cell to the welding station for welding through the cell welding mechanism. During welding, the welding light box can further ensure that the welding heat is not lost and improve the welding quality; S7. After welding is completed, the gripping mechanism grabs and removes the battery cell tooling, and the welded single battery cell enters the inspection station, and the pressure pins of the inspection pressure pin assembly on one side of the gripping mechanism apply current and voltage to both ends of the single battery cell, and the inspection camera takes a picture of it for EL inspection.

Images