Photovoltaic soldering strip and method for manufacturing the same

Abstract

The application discloses a kind of photovoltaic welding band and preparation method thereof, specifically relates to photovoltaic welding band technical field, and photovoltaic welding band includes main band, the top end of the main band is equipped with multiple vice bands, the two ends of the vice band are welded and fixed with main band, the middle part of the vice band is not welded and fixed with main band, the upper and lower ends of the main band and vice band are equipped with solder layer, the main band and vice band are welded and fixed by solder layer, the main band, vice band are made of copper, and the raw material of the solder layer includes tin 60 parts and lead 40 parts according to weight fraction.The application is welded with multiple vice bands on the main band, when the photovoltaic welding band is used as bus band, corresponding one end of interconnecting strip is inserted into the gap between the main band and one of vice bands, then heating is welded, and the upper and lower sides of interconnecting strip are welded and fixed in this welding mode, so that the strength of welding is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic ribbon technology, and more specifically to a photovoltaic ribbon and its preparation method. Background Technology

[0002] Photovoltaic solder ribbon, also known as tin-plated copper ribbon or tin-coated copper ribbon, is an important component used for connecting the cells of photovoltaic modules. It consists of a substrate and a surface coating. The substrate is generally made of copper with good conductivity, while the surface coating is made of tin alloy to ensure that the solder ribbon is solderable.

[0003] Photovoltaic welding ribbons are mainly divided into busbars and interconnecting strips. Interconnecting strips are used to weld individual solar cells together in rows, and one end of the interconnecting strip after being welded together is welded to the busbar. A busbar often connects multiple busbars.

[0004] In the prior art, both busbars and interconnects are covered with a solder layer, such as the photovoltaic solder strip and its preparation method disclosed in the prior art with publication number CN106653910B.

[0005] The busbar is welded to the interconnect strip through a solder layer. Both sides of the busbar have solder, but only one side comes into contact with the other during welding, which means that the connection strength between the two during welding needs to be improved. Summary of the Invention

[0006] The purpose of this invention is to provide a photovoltaic welding strip and its preparation method. By welding multiple sub-strips onto the main strip, inserting one end of the interconnect strip into the gap between the main strip and one of the sub-strips, and then heating and welding, this welding method ensures that the interconnect strip is welded and fixed on both the upper and lower sides, effectively improving the welding strength.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a photovoltaic welding strip, comprising a main strip, wherein a plurality of sub-strips are provided at the top end of the main strip, the two ends of the sub-strips are welded and fixed to the main strip, and the middle part of the sub-strips is not welded and fixed to the main strip;

[0008] Both the upper and lower ends of the main belt and the auxiliary belt are provided with solder layers, and the main belt and the auxiliary belt are fixed by welding through the solder layers.

[0009] Furthermore, both the main strip and the auxiliary strip are made of copper, and the raw materials of the solder layer include 60 parts tin and 40 parts lead by weight.

[0010] Furthermore, the thickness of the main belt is 0.15mm, the thickness of the secondary belt is 0.1mm, and there is a gap between two adjacent secondary belts. The gap is an area on the main belt that is not covered by the secondary belt. The length of each gap is 5-10mm, and the gap can be bent into an inverted V shape during use.

[0011] This invention also includes a method for preparing the photovoltaic ribbon, the specific steps of which are as follows:

[0012] Step 1: Using copper as raw material, extrude two copper plates, one thick and one thin. The thickness of the thick copper plate is 0.15mm, and the thickness of the thin copper plate is 0.1mm.

[0013] Step 2: Electroplating is performed on the two copper plates, and a solder layer is formed on the surface of the copper plates after electroplating;

[0014] Step 3: Cut the electroplated copper plate into narrow strips of uniform width, 5mm wide, or adjust the width as needed;

[0015] Step 4: Use a grinding device to grind the two sides of the narrow strip. After grinding, the narrow strip of thick copper plate is made into the main strip.

[0016] Step 5: After polishing, the narrow strip made of thin copper plate is cut into short segments of the same length. These short segments are called auxiliary strips, and each auxiliary strip is 20mm long.

[0017] Step 6: Weld the auxiliary strips evenly to the top of the main strip. The two ends of the auxiliary strips are welded and fixed to the main strip with a width of 5mm. The middle 10mm of each auxiliary strip is not welded and fixed to the main strip. Either end can be made into a photovoltaic welding strip, which can be used as a busbar.

[0018] Furthermore, the edge grinding device in step four includes a base, the top of which is provided with a linear motor, a resistance mechanism, a pulling mechanism, and two grinding components. The linear motor has two moving parts, and the two grinding components are respectively located on the two moving parts of the linear motor, and the two grinding components are arranged symmetrically from left to right. The linear motor is located between the resistance mechanism and the pulling mechanism.

[0019] Furthermore, the grinding assembly includes a vertical plate located at the top of the linear motor actuator, a scroll on one side of the vertical plate, and fixed plates rotatably connected to both ends of the scroll. The fixed plates are fixedly located on one side of the vertical plate, and torsion springs are provided at both ends of the scroll. The two ends of the torsion springs are respectively fixedly connected to the outer end of the scroll and the fixed plate on the corresponding side.

[0020] The outer end of the reel is wound with a sanding belt, and the top of the reel is provided with a fixing block fixed to the upright plate. The fixing block has a slot, and one end of the sanding belt passes through the slot and passes through the fixing block. The fixing block is provided with two fastening bolts by threads.

[0021] Furthermore, the resistance mechanism is located behind the linear motor. The resistance mechanism includes two rear end plates fixed to the top of the base. Two rear rollers are arranged vertically between the two rear end plates. The two ends of the rear rollers are rotatably connected to the two rear end plates respectively. Two rear rubber sleeves are fixedly provided on the outer ends of the rear rollers, and the two rear rubber sleeves are in contact with each other.

[0022] Furthermore, the pulling mechanism includes two front end plates fixed to the top of the base, and two front rollers distributed vertically between the two front end plates. The two ends of the front rollers are rotatably connected to the two front end plates respectively, and a front rubber sleeve is fixedly provided on the outer end of the front rollers. The two front rubber sleeves are in contact with each other.

[0023] The outer end of the front roller is fixedly provided with a gear, the two gears mesh with each other, and a drive motor for driving one of the front rollers to rotate is fixedly provided on one of the front end plates.

[0024] The technical effects and advantages provided by the present invention in the above technical solution are as follows:

[0025] 1. By welding multiple sub-strips onto the main strip, when the photovoltaic welding strip is used as a busbar, one end of the interconnecting strip is inserted into the gap between the main strip and one of the sub-strips, and then heated and welded. In this welding method, the upper and lower sides of the interconnecting strip are welded and fixed, which effectively improves the welding strength.

[0026] 2. The gap between two adjacent sub-strips is bent into an inverted V-shape. Stretching or compression will change the angle of the V-shape. In this way, the elasticity of the gap itself plays a buffering role in thermal expansion and contraction, reducing the adverse effects of thermal expansion and contraction on the photovoltaic welding strip.

[0027] 3. During the processing and manufacturing of the main belt and auxiliary belt, the edges on both sides of the main belt and auxiliary belt are ground by using an edge grinding device to make the cuts on the edges smoother, reduce their sharpness, and avoid the edges of the main belt and auxiliary belt after forming being too sharp and causing cuts. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0029] Figure 1 This is a structural diagram of the photovoltaic ribbon of the present invention;

[0030] Figure 2 This is a schematic diagram showing the bending state of the interstices in the photovoltaic ribbon.

[0031] Figure 3 This is a cross-sectional view of the main strip of the photovoltaic welding ribbon;

[0032] Figure 4 This is a structural diagram of the edge grinding device in the photovoltaic ribbon preparation method;

[0033] Figure 5 This is a structural diagram of the grinding component of the edge grinding device;

[0034] Figure 6 This is a structural diagram of the resistance mechanism of the edge grinding device;

[0035] Figure 7 This is a structural diagram of the pulling mechanism of the edge grinding device.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1. Main belt; 2. Sub-belt; 3. Spacing zone; 4. Solder layer; 5. Base; 6. Linear motor; 7. Resistance mechanism; 701. Rear roller; 702. Rear rubber sleeve; 703. Rear end plate; 8. Pulling mechanism; 801. Front roller; 802. Front rubber sleeve; 803. Front end plate; 804. Drive motor; 805. Gear; 9. Grinding assembly; 901. Vertical plate; 902. Fixing block; 903. Reel; 904. Fixing plate; 905. Torsion spring; 906. Grinding sanding belt. Detailed Implementation

[0038] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0039] This invention provides, for example Figure 1-3 The photovoltaic welding strip shown includes a main strip 1, with a plurality of sub-strips 2 at the top end of the main strip 1. The two ends of the sub-strips 2 are welded and fixed to the main strip 1, while the middle part of the sub-strips 2 is not welded and fixed to the main strip 1.

[0040] Both the upper and lower ends of the main belt 1 and the auxiliary belt 2 are provided with solder layers 4, and the main belt 1 and the auxiliary belt 2 are welded and fixed by solder layers 4.

[0041] The main strip 1 and the auxiliary strip 2 are both made of copper. The raw materials of the solder layer 4 include 60 parts tin and 40 parts lead by weight. The solder layer 4 made therefrom has a melting point of 183°C, which is more suitable for welding. In addition, the tin-lead alloy has good oxidation resistance and corrosion resistance.

[0042] By welding multiple sub-strips 2 onto the main strip 1, the main strip 1 and sub-strips 2 together form the main body of the photovoltaic welding strip, which is used as a busbar. When welding with the interconnecting strip, one end of the interconnecting strip is inserted into the gap between the main strip 1 and one of the sub-strips 2, and then heated and welded. Since both the main strip 1 and the sub-strips 2 have a solder layer 4 on their surfaces, the interconnecting strip inserted into the gap is welded and fixed to the sub-strips 2 and the main strip 1 on its upper and lower sides, respectively. Compared with the prior art where only one side is welded and fixed, this welding method welds and fixes the interconnecting strip on both the upper and lower sides, effectively improving the welding strength.

[0043] To reduce the impact of temperature changes on the photovoltaic ribbon, such as Figure 2 As shown, the thickness of the main belt 1 is 0.15mm, the thickness of the secondary belt 2 is 0.1mm, and there is a gap 3 between two adjacent secondary belts 2. The gap 3 is the area on the main belt 1 that is not covered by the secondary belt 2. The length of each gap 3 is 5-10mm, and the gap 3 can be bent into an inverted V shape when in use.

[0044] When in use, the gap 3 between two adjacent sub-strips 2 can be bent into an inverted V shape. In this way, when the photovoltaic welding strip expands and contracts due to temperature changes during use, the V-shaped gap 3 will be stretched or compressed. The stretching or compression will change the angle of the V shape, thereby using the elasticity of the gap 3 itself to buffer the thermal expansion and contraction, reducing the adverse effects of thermal expansion and contraction on the photovoltaic welding strip.

[0045] This invention also includes a method for preparing the photovoltaic ribbon, the specific steps of which are as follows:

[0046] Step 1: Using copper as raw material, extrude two copper plates, one thick and one thin. The thickness of the thick copper plate is 0.15mm, and the thickness of the thin copper plate is 0.1mm.

[0047] Step 2: Electroplating is performed on the two copper plates, and a solder layer 4 is formed on the surface of the copper plates after electroplating;

[0048] Step 3: Cut the electroplated copper plate into narrow strips of uniform width, 5mm wide, or adjust the width as needed;

[0049] Step 4: Use a grinding device to grind the two sides of the narrow strip. After grinding, the narrow strip of the thick copper plate is made into the main strip 1.

[0050] Step 5: After polishing, the narrow strip made of thin copper plate is cut into short segments of the same length. These short segments are called sub-strips 2, and each sub-strip 2 is 20mm long.

[0051] Step 6: Weld the secondary strip 2 evenly to the top of the main strip 1. Each end of the secondary strip 2 is 5mm wide and welded to the main strip 1. The middle 10mm of each section of the secondary strip 2 is not welded to the main strip 1. Either end can be made into a photovoltaic welding strip, which can be used as a busbar.

[0052] The edge grinding device in step four includes a base 5, such as... Figure 4-7 As shown, the top of the base 5 is provided with a linear motor 6, a resistance mechanism 7, a pulling mechanism 8 and two grinding components 9. The linear motor 6 is provided with two moving parts, and the two grinding components 9 are respectively provided on the two moving parts of the linear motor 6. The two grinding components 9 are arranged symmetrically from left to right. The linear motor 6 is located between the resistance mechanism 7 and the pulling mechanism 8.

[0053] The grinding assembly 9 includes a vertical plate 901 located at the top of the mover of the linear motor 6. A roller 903 is provided on one side of the vertical plate 901. Fixed plates 904 are rotatably connected to both ends of the roller 903. The fixed plates 904 are fixedly located on one side of the vertical plate 901. Torsion springs 905 are provided at both ends of the roller 903. The two ends of the torsion springs 905 are respectively fixedly connected to the outer end of the roller 903 and the fixed plate 904 on the corresponding side.

[0054] The outer end of the reel 903 is wound with a sanding belt 906. The top of the reel 903 is provided with a fixing block 902 fixed on the upright plate 901. The fixing block 902 has a slot. One end of the sanding belt 906 passes through the slot and passes through the fixing block 902. The fixing block 902 is provided with two fastening bolts by threads.

[0055] After electroplating, the copper plate is cut into narrow strips. The narrow strips pass through the resistance mechanism 7 and the pulling mechanism 8. The pulling mechanism 8 pulls the narrow strips to move. During the movement, the narrow strips pass between two grinding components 9. The two grinding components 9 grind the two sides of the narrow strips respectively. The linear motor 6 adjusts the position of the two grinding components 9 so that the grinding belt 906 contacts the edge of the narrow strip. In this way, during the movement of the narrow strips, its edge will rub against the grinding belt 906, thereby achieving the purpose of grinding. After grinding, the burrs at the edge of the narrow strips can be reduced, making the cut at the edge smoother and reducing its sharpness. This avoids the edges of the main belt 1 and the auxiliary belt 2 after forming being too sharp and causing cuts.

[0056] One end of the sanding belt 906 is fixed to the fixing block 902, and the other end is wound and fixed to the roller 903. The elastic force of the torsion spring 905 drives the roller 903 and pulls the sanding belt 906 downward, so that the sanding belt 906 is in a taut state, so that the sanding belt 906 can contact the edge of the narrow strip. It can also pull the sanding belt 906 upward to adjust the contact position between the sanding belt 906 and the narrow strip, so as to avoid severe wear on the same part of the sanding belt 906 after long-term use.

[0057] During the polishing process, the narrow strip should be kept as taut as possible, such as... Figure 4 , 6 As shown, the resistance mechanism 7 is located behind the linear motor 6. The resistance mechanism 7 includes two rear end plates 703 fixed to the top of the base 5. Two rear rollers 701 are arranged vertically between the two rear end plates 703. The two ends of the rear rollers 701 are rotatably connected to the two rear end plates 703 respectively. The rear rollers 701 have a certain damping when rotating. Two rear rubber sleeves 702 are fixedly provided on the outer end of the rear rollers 701. The two rear rubber sleeves 702 are in contact with each other.

[0058] Before the narrow strip reaches the grinding assembly 9 for grinding, it first passes through the resistance mechanism 7. The narrow strip is clamped between the two rear rubber sleeves 702. The narrow strip, pulled by the pulling mechanism 8, drives the rear rubber sleeves 702 and the rear roller 701 to rotate during the movement. The rotation of the rear roller 701 has damping, and under the action of damping, the narrow strip is stretched as straight as possible.

[0059] To drive continuous motion of narrow strips, such as Figure 4 , 7 As shown, the pulling mechanism 8 includes two front end plates 803 fixed to the top of the base 5. Two front rollers 801 are arranged vertically between the two front end plates 803. The two ends of the front rollers 801 are rotatably connected to the two front end plates 803 respectively. A front rubber sleeve 802 is fixedly provided on the outer end of the front rollers 801. The two front rubber sleeves 802 are in contact with each other.

[0060] A gear 805 is fixedly provided at the outer end of the front roller 801, and two gears 805 mesh with each other. A drive motor 804 for driving one of the front rollers 801 to rotate is fixedly provided on one of the front end plates 803.

[0061] The front end of the narrow strip is clamped between two front rubber sleeves 802. One of the front rollers 801 is driven to rotate by the drive motor 804. Under the meshing action of two gears 805, the two front rollers 801 rotate synchronously and drive the two front rubber sleeves 802 to rotate, thereby pulling the narrow strip to move.

[0062] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A photovoltaic welding strip, comprising a main strip (1), characterized in that: The main belt (1) has multiple sub-belts (2) at its top end. The two ends of the sub-belts (2) are welded and fixed to the main belt (1), while the middle part of the sub-belts (2) is not welded and fixed to the main belt (1). The main strip (1) and the auxiliary strip (2) are provided with solder layers (4) at both ends, and the main strip (1) and the auxiliary strip (2) are welded and fixed by solder layers (4).

2. The photovoltaic welding strip according to claim 1, characterized in that: The main strip (1) and the secondary strip (2) are both made of copper, and the raw materials of the solder layer (4) include 60 parts of tin and 40 parts of lead by weight.

3. The photovoltaic welding strip according to claim 1, characterized in that: The thickness of the main belt (1) is 0.15 mm, the thickness of the secondary belt (2) is 0.1 mm, and a gap area (3) is provided between two adjacent secondary belts (2). The gap area (3) can be bent into an inverted V shape when in use.

4. The method for preparing photovoltaic solder ribbon according to any one of claims 1-3, characterized in that: The specific steps are as follows: Step 1: Using copper as raw material, extrude two copper plates, one thick and one thin; Step 2: Electroplating the two copper plates; Step 3: Cut the electroplated copper plate into narrow strips of uniform width; Step 4: Use a grinding device to grind the two sides of the narrow strip. After grinding, the narrow strip of the thick copper plate is made into the main strip (1). Step 5: After polishing, the narrow strip made of thin copper plate is cut into short segments of the same length, which are the secondary strips (2); Step 6: Weld the secondary strip (2) evenly at intervals to the top of the main strip (1), and any one end can be made into a photovoltaic welding strip.

5. The method for preparing photovoltaic solder ribbon according to claim 4, characterized in that: The edge grinding device in step four includes a base (5). The top of the base (5) is provided with a linear motor (6), a resistance mechanism (7), a pulling mechanism (8), and two grinding components (9). The linear motor (6) is provided with two moving parts. The two grinding components (9) are respectively provided on the two moving parts of the linear motor (6) and the two grinding components (9) are arranged symmetrically on the left and right. The linear motor (6) is located between the resistance mechanism (7) and the pulling mechanism (8).

6. The method for preparing photovoltaic solder ribbon according to claim 5, characterized in that: The grinding assembly (9) includes a vertical plate (901) located at the top of the mover of the linear motor (6). A roller (903) is provided on one side of the vertical plate (901). A fixing plate (904) is rotatably connected to both ends of the roller (903). The fixing plate (904) is fixedly located on one side of the vertical plate (901). A torsion spring (905) is provided at both ends of the roller (903). The outer end of the reel (903) is wound with a sanding belt (906). The top of the reel (903) is provided with a fixing block (902) fixed on the upright plate (901). The fixing block (902) has a slot. One end of the sanding belt (906) passes through the fixing block (902) through the slot. The fixing block (902) is provided with two fastening bolts by threads.

7. The method for preparing photovoltaic solder ribbon according to claim 5, characterized in that: The resistance mechanism (7) is located behind the linear motor (6). The resistance mechanism (7) includes two rear end plates (703) fixed to the top of the base (5). Two rear rollers (701) are arranged vertically between the two rear end plates (703). Two rear rubber sleeves (702) are fixed at the outer ends of the rear rollers (701) and the two rear rubber sleeves (702) are in contact with each other.

8. The method for preparing photovoltaic solder ribbon according to claim 5, characterized in that: The pulling mechanism (8) includes two front end plates (803) fixed to the top of the base (5), and two front rollers (801) distributed vertically between the two front end plates (803). The outer ends of the front rollers (801) are fixed with front rubber sleeves (802), and the two front rubber sleeves (802) are in contact with each other. A gear (805) is fixedly provided at the outer end of the front roller (801), and the two gears (805) mesh with each other. A drive motor (804) for driving one of the front rollers (801) to rotate is fixedly provided on one of the front end plates (803).

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