Solar cell and preparation method and device of electrode of solar cell

Abstract

The invention discloses a solar cell and a preparation method and device of an electrode of the solar cell, and relates to the technical field of silicon wafer half cutting. A tunnel layer on a first surface of a semiconductor substrate and a first conductive type semiconductor region on the tunnel layer contain semiconductor impurities of the first conductive type; according to the invention, through arranging the moving part, the conductive seed layer is uniformly distributed on the silicon wafer in a segmented manner, is distributed in a whole segment manner or is vertical to the fine grids, and is distributed below all the fine grids at the same time, the conductive seed layer accounts for about 30-120% of the contact area of the primary cell and the grid lines, and the silver consumption is about 25% of the original silver consumption. The back surface adopts a main-grid-free technology, the silver consumption can be effectively reduced by more than 10%, the reduction of the shading area of the back surface can improve the double-sided rate, and the main grid only plays a role in conducting current, does not generate gain to the current, but shields the absorption area of light, so that the current is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of silicon wafer half-slice cutting, and in particular to a solar cell, and a method and device for preparing an electrode thereof. Background Art

[0002] With the rapid development of various industries, the global demand for silver has increased by more than 30% since 2017. The current global annual supply of silver is 28,000 tons, and the annual gap is 6,720 tons. Silver is increasingly in short supply. The price of silver has risen from 3.87 yuan / g in 2017 to 7.48 yuan / g in 2024, an increase of 93.3%. Silver paste, as an important raw material in the photovoltaic industry, accounts for about 45% of the manufacturing cost and about 25% of the total cost. The cost of silver paste is the key to cost reduction projects; battery power = efficiency * area * light intensity; efficiency = 0.1 * (short-circuit current * open-circuit voltage * fill factor); from the process factors From the basic point of view, the main influencing factors of short-circuit current are: the ability to absorb light per unit area, which is further affected by the anti-reflection film, metallization resistor and pn junction; the ability of a single cell to absorb light, which is further affected by the metallization shading area and the total area of ​​the silicon wafer; the metal graphic electrode of the solar crystalline silicon cell mainly plays the role of collecting and transmitting current, and the electrode width and height dimensions are micron-level, generally requiring a large aspect ratio to reduce the shading area and reduce the current transmission resistance; the price of silver is high, the cost of using precious metals is high, and there is a gap in the supply of silver. The metallization grid line will block the light-absorbing area and reduce the absorption of light; The existing technical solution uses silver paste for metallization process. Silver is a precious metal and is expensive. The use of conventional base metals will greatly reduce the manufacturing cost. The conductivity of conventional metal conductive wires is lower than that of the grid lines formed by silver paste, and a silver seed layer is needed to be effectively improved. Summary of the invention

[0003] In view of the shortcomings of the prior art, the present invention solves the technical problems by adopting the following technical solutions: A solar cell according to the present invention comprises: a tunnel layer on a first surface of a semiconductor substrate; The first conductive type semiconductor region on the tunnel layer contains semiconductor impurities of the first conductive type; semiconductor impurities of the second conductive type opposite to the first conductive type are located on the second surface of the semiconductor substrate and opposite to the first conductive type semiconductor region; The first passivation film on the first conductivity type semiconductor region: A battery bus bar parallel to the long side formed on the first passivation film and fixed to the edge by welding or the like; A first electrode formed on the first passivation film, connected to the first conductive type semiconductor through the first passivation film and connected to the second surface battery conductive wire through a battery bus bar; A second passivation film A and a second passivation film B on the second conductivity type semiconductor region; The battery metal seed layer formed on the second passivation film B may be made of metals such as silver and nickel; A metal conductive wire formed on the second passivation film B and completely covering the seed layer and connected to the first surface battery bus bar; It also includes a coated silicon wafer, an electrode metal seed layer, an electrode bus bar, an electrode conductive wire, a gate wire and a connecting wire; The electrode metal seed layer and the electrode conductive wire are both arranged on the second surface of the coated silicon wafer, the back side of the coated silicon wafer is the first surface, and the front side of the coated silicon wafer is the second surface, the electrode bus bar, the gate line and the connecting line are arranged on the back side of the silicon wafer, and the distribution of the electrode metal seed layer is any one of segmented uniform distribution, whole segment distribution and vertical to the fine gate distribution; A method for preparing a solar cell electrode comprises the following steps: S1: Cut the coated silicon wafer into half pieces using a cutting device; S2: screen-printing a second surface silver seed layer on the coated silicon wafer, and setting an electrode metal seed layer on the surface of the battery cell, wherein the electrode metal seed layer is used to improve the contact between the electrode conductive wire and the coated silicon wafer; S3: welding the electrode bus bar to the first surface of the coated silicon wafer parallel to the single long side; S4: The electrode conductive wire is a wire that conducts the current longitudinally and transversely. The electrode conductive wire is fixed on the conductive layer by glue and contacts the conductive layer, and is connected to the first surface electrode bus bar; S5: Use UV light box to cure the glue; S6: printing grid lines on the first surface, the direction of which intersects with the electrode conductive wires, and connecting lines connected to the electrode bus bars; Preferably, the step S3 of welding the electrode bus bar to the first surface of the coated silicon wafer parallel to a single long side includes the following steps: S301: Prepare electrode bus bars, welding materials, laser welding machines, and fixtures and positioning tools for fixing silicon wafers and electrode bus bars that meet the requirements; S302: Positioning the electrode busbar: According to the design requirements of the battery cell, the welding position of the electrode busbar on the first surface of the silicon wafer is clarified. The electrode busbar should be parallel to the long side. With the help of a positioning tool, the electrode busbar is accurately placed at the specified position on the first surface of the silicon wafer to ensure a tight fit and straightness. S303: Laser welding operation: accurately place the welding piece at the contact part to ensure close fit, set the laser power, pulse frequency and other parameters according to the material, turn on the equipment, observe whether the welding has any defects, and re-weld after timely handling if there are any problems; S304: Inspection and processing after welding, check whether there are defects such as cold welding and desoldering at the welding parts, and place the silicon wafer in a specified area to wait for subsequent steps; Preferably, the laser welding operation in step S303 includes the following steps: S3031: Place the solder and accurately place the preformed solder sheet at the contact position between the electrode bus bar and the first surface of the silicon wafer, ensuring that they fit tightly with no gaps and the size matches the welding position; S3032: Set welding parameters according to factors such as electrode busbar, silicon wafer material, welding sheet thickness and equipment performance. When welding electrode busbar and coated silicon wafer, use 0.1-0.15mm thick welding sheet, set laser power to 100-200W, pulse frequency to 10-20kHz, welding speed to 1-3 / s, and adjust the focus position to the center of the welding part; S3033: Turn on the equipment and irradiate the welding part according to the set parameters. Observe closely during welding. If the welding piece is not melted well or there is a porosity defect, stop welding in time and adjust the parameters.

[0004] The metal seed layer is composed of a plurality of metal printing dots, the width of the metal seed layer is 3-30um, the height is 2-15um, the mesh number of the printing screen is 400-800 mesh, the wire diameter is 3-30μm; the yarn thickness is 3-30μm, the film thickness is 2-10μm; the printing line width is 5-15μm, the electrode busbar width is 0.1-3mm, the glue is any one of light curing glue and thermosetting glue, and the material of the metal conductive wire can be one or more of silver, copper, aluminum, nickel, gold, calcium, tungsten, zinc, lithium, etc.; Cutting equipment includes: A workbench, wherein a laser cutting component is fixedly connected to the top of the workbench, a loading component is fixedly connected to the side of the top of the workbench away from the laser cutting component, a transmission component is fixedly connected to the axis of the top of the workbench, a collecting component is fixedly connected to the inner side of the workbench, and a unloading component is fixedly connected to the side of the top of the workbench away from the loading component; A moving component, which is used to grab the silicon wafer, and the bottom of the moving component is fixedly connected to the top of the workbench; Preferably, the moving component includes a support frame, the bottom of the support frame is fixedly connected to the top of the workbench, the side of the support frame is slidably connected to a control mechanism, the bottom of the control mechanism is symmetrically provided with a grabbing mechanism, and the center of the bottom of the control mechanism is fixedly connected to a cleaning mechanism; the grabbing mechanism is driven to move to the left side of the support frame by the control mechanism, so that the grabbing mechanism grabs the silicon wafer on the feeding component, thereby placing the silicon wafer on the transmission component, and the silicon wafer is driven to the bottom of the laser cutting component by the transmission component, so that the laser cutting component cuts the silicon wafer on the transmission component, and after the laser cutting component cuts the silicon wafer, the cut silicon wafer is driven to the support frame by the transmission component. Under the support frame, the two grasping mechanisms are driven to move to the left side of the support frame by the control mechanism, so that the grasping mechanism on the right side grasps the silicon wafer after cutting. At the same time, when the grasping mechanism on the right side grasps downward, the grasping mechanism on the left side can grasp the silicon wafer on the loading component at the same time. When the control mechanism drives the grasping mechanism to move to the right side, the grasping mechanism on the right side places the cut silicon wafer on the unloading component for unloading, and the grasping mechanism on the left side places the silicon wafer on the transmission component, and can drive the cleaning mechanism to clean the side of the transmission component, so as to avoid residual processing waste on the transmission component, thereby interfering with subsequent cutting work; Preferably, the cleaning mechanism includes a cleaning frame, the top of the cleaning frame is fixedly connected to the bottom of the control mechanism, the inner side of the cleaning frame is slidably connected to a sliding frame, the middle part of the bottom of the cleaning frame is fixedly connected to a telescopic rod, a first spring is sleeved on the telescopic rod, the top of the first spring is fixedly connected to the cleaning frame, the bottom of the first spring is fixedly connected to the top of the connecting plate, the bottom of the sliding frame is fixedly connected to a connecting plate, the bottom of the telescopic rod is fixedly connected to the connecting plate, the side of the connecting plate is fixedly connected to a bent plate, the side of the bent plate away from the connecting plate is rotatably connected to a cleaning roller, and the connecting plate A fixed plate is fixedly connected to one side away from the bent plate, and a scraper is fixedly connected to one side of the fixed plate away from the mesh plate; when the control mechanism drives the grabbing mechanism to move to the left, the control mechanism drives the cleaning frame to move together, so that the cleaning frame drives the fixed plate and the scraper through the sliding frame to clean the placement platform on the transmission component, and after the scraper cleans the top of the placement platform, the curved plate can drive the cleaning roller to clean and wipe the top of the placement platform, and two scrapers are arranged at the bottom of the fixed plate, and the material of the scraper is rubber, so that the scraper can clean the top of the placement platform When cleaning the top of the platform, when one side of the scraper contacts the top of the placement platform for cleaning, the scraper in contact with the top of the placement platform is subjected to the squeeze force, so that the other scraper can be bent and lifted, so that when the control mechanism drives the grabbing mechanism to move to the left, the scraper can contact and clean the top of the placement platform, thereby preventing silicon wafer impurities after cutting from remaining on the top of the placement platform. At the same time, when the control mechanism drives the grabbing mechanism to move to the right, the bent plate can drive the scraper to perform secondary reverse cleaning on the top of the placement platform. There are two scrapers, and the material of the scrapers is rubber, so as to avoid the scraper being scratched when cleaning the top of the placement platform for the first time. When the control mechanism drives the grabbing mechanism to move to the right, it will make a second contact with the top of the placement platform, so that the impurities adhered to the scraper will fall on the top of the placement platform, resulting in the phenomenon that impurities still remain on the top of the placement platform when the silicon wafer is placed. When the extrusion force between the scraper and the top of the placement platform is greater than the tensile force of the first spring, the connecting plate drives the scraper to slide upward on the inner side of the cleaning frame, so as to avoid excessive extrusion force between the scraper and the top of the placement platform; Preferably, the collecting component includes a collecting box, the side of the collecting box is fixedly connected to the inner side of the workbench, the top of the collecting box is fixedly connected to a mesh plate, the bottom of the inner cavity of the collecting box is fixedly connected to an air suction mechanism, the top of the air suction mechanism is fixedly connected to an activated carbon plate, the bottom of the mesh plate is slidably connected to a connecting shaft, the bottom of the connecting shaft is fixedly connected to a bracket, a second spring is sleeved on the connecting shaft, the top of the second spring is fixedly connected to the bottom of the mesh plate, the bottom of the second spring is fixedly connected to the bracket, and the top of the bracket is fixedly connected to an ejection mechanism; the laser cutting component cuts the silicon wafer on the transmission component, and by opening the air suction mechanism, the waste chips and exhaust gas generated during processing can be discharged through the exhaust pipe. The exhaust gas is sucked into the collection box through the mesh plate, and the exhaust gas is filtered by the activated carbon plate. The exhaust gas is discharged through the suction mechanism to prevent the exhaust gas generated during the half-wafer cutting process from containing silicon dust. When the human body inhales these silicon dusts, they will be deposited in the lungs. Long-term exposure to a high concentration of silicon dust environment will lead to silicosis. At the same time, the suction force generated by the suction mechanism when it is working causes the bracket to move downward through the connecting shaft, so that the bracket drives the ejection mechanism to detach from the mesh plate. When the collection work is completed and the suction mechanism stops working, the bracket is driven by the stretching of the second spring, so that the bracket drives the ejection mechanism to reset the mesh plate, thereby preventing impurities from being blocked in the mesh holes of the mesh plate when collecting impurities; Preferably, the ejection mechanism includes an ejection rod, the ejection rod is concentrically arranged with the mesh of the screen, the bottom of the ejection rod is fixedly connected to the bracket, the inner side of the ejection rod is slidably connected with a slider, the side of the slider is fixedly connected with a sliding shaft, the side of the sliding shaft is slidably connected to the inner side of the ejection rod, the top of the sliding shaft is fixedly connected with an ejector pin, the sliding shaft is sleeved with a third spring, the top of the third spring is fixedly connected to the ejector pin, and the bottom of the third spring is fixedly connected to the top of the ejection rod; after the collection work is completed, when the suction mechanism stops working, the bracket is driven by the stretching of the second spring, so that the bracket drives the ejection rod to reset the screen. , and at the same time, the ejector rod drives the ejector pin to eject the impurities stuck in the mesh. At the same time, when the ejector pin is cleaning the blockage at the mesh of the mesh plate, when the extrusion force between the ejector pin and the impurities stuck in the mesh is greater than the tensile force of the third spring, the ejector pin is moved downward through the sliding shaft and the slider. At the same time, the buffering work of the third spring is used to avoid excessive extrusion force between the ejector pin and the mesh, which may cause extrusion damage to the ejector pin. At the same time, excessive impact force between the ejector pin and the impurities stuck in the mesh is avoided, which may cause excessive extrusion force between the impurities and the inner side of the mesh, thereby causing friction damage to the inner wall of the mesh, thereby causing damage to the mesh aperture. Preferably, the unloading component includes an unloading shell, the side surface of the unloading shell is fixedly connected to the inner side of the workbench, the inner side of the unloading shell is rotatably connected to a conveyor belt, the inner side of the unloading shell is fixedly connected to a contact mechanism, and the contact mechanism is arranged at the bottom of the conveyor belt; when the grabbing mechanism places the half-cut silicon wafer on the conveyor belt, the silicon wafer is unloaded by conveying. At the same time, when the conveyor belt is used for conveying and unloading the cut silicon wafer for a long time, some processing debris will remain on the conveyor belt, thereby preventing impurities adhering to the conveyor belt from interfering with the placement position of the silicon wafer during the subsequent conveying of the silicon wafer, thereby interfering with the unloading of the silicon wafer. When the conveyor belt is unloading, the conveyor belt is contacted and moved with the contact mechanism, so that the contact mechanism can clean the side surface of the conveyor belt, thereby preventing a large amount of processing impurities from remaining on the side surface of the conveyor belt when the conveyor belt is used for conveying and unloading the cut silicon wafer for a long time. Preferably, the contact mechanism includes a contact frame, the side surface of the contact frame is fixedly connected to the inner side of the material discharge shell, the inner side of the contact frame is slidably connected with a moving rod, the top of the moving rod is fixedly connected with a contact plate, a fourth spring is sleeved on the moving rod, the top of the fourth spring is fixedly connected to the contact plate, the bottom of the fourth spring is fixedly connected to the inner side of the contact frame, the inner side of the contact plate is rotatably connected with a contact shaft, the side surface of the contact shaft is fixedly connected with a rubber plate, the side of the contact shaft away from the rubber plate is fixedly connected with a scratch plate, and the side surface of the scratch plate is in contact with the conveyor belt; when the conveyor belt is performing the material discharge work, the conveyor belt and the rubber plate are connected to the material. The contact plate is moved to contact and move, so that the rubber plate can clean the side of the conveyor belt. At the same time, when the conveyor belt contacts the rubber plate, the rubber plate can drive the moving rod to rotate inside the contact plate, so that the scratch plate can contact and clean the conveyor belt at the same time. By evenly opening square grooves on the scratch plate, the scratch plate can scrape out some processing impurities stuck on the conveyor belt. At the same time, to avoid excessive squeezing pressure between the scratch plate and the conveyor belt, the contact plate can move downward through the moving rod. At the same time, through the buffering of the fourth spring, it can avoid excessive squeezing pressure between the scratch plate and the conveyor belt, which will cause friction damage to the side of the conveyor belt.

[0005] The beneficial effects of the present invention are as follows: 1. The present invention distributes the conductive seed layer evenly in sections on the silicon wafer and at the same time distributes it under all the fine grids, accounting for about 30%-120% of the contact area between the original cell and the grid line, and using about 25% of the original silver consumption, which can greatly reduce the silver consumption. The back side adopts the main grid-free technology, which can effectively reduce the silver consumption by more than 10%. The reduction of the back side shading area can improve the double-sidedness. The photogenerated carriers are mainly collected by the sub-grid. The main grid only plays the role of conducting current and will not generate gain for the current. Instead, it will block the light absorption area, thereby reducing the current.

[0006] 2. The present invention sets a moving part, and drives the grasping mechanism to move to the left side of the support frame through a control mechanism, so that the grasping mechanism grasps the silicon wafer on the loading part, and then puts the silicon wafer onto the transmission part, and drives the silicon wafer to the bottom of the laser cutting part through the transmission part, so that the laser cutting part cuts the silicon wafer on the transmission part.

[0007] 3. The present invention provides a cleaning mechanism. When the control mechanism drives the grabbing mechanism to move to the left, the control mechanism drives the cleaning frame to move together. Therefore, the cleaning frame drives the fixed plate and the scraper through the sliding frame to clean the placement platform on the transmission component. After the scraper cleans the top of the placement platform, it can drive the cleaning roller to clean and wipe the top of the placement platform through the bent plate. Two scrapers are provided at the bottom of the fixed plate, and the material of the scraper is rubber. Therefore, when the scraper cleans the top of the placement platform, when one side of the scraper contacts the top of the placement platform for cleaning, the scraper in contact with the top of the placement platform is subjected to the extrusion force, so that the other scraper can be bent and lifted.

[0008] 4. The present invention is provided with an ejection mechanism. After the collection work is completed, when the suction mechanism stops working, the bracket is driven by the stretching of the second spring, so that the bracket drives the ejection rod to reset the mesh plate, and at the same time, the ejection rod drives the ejector to eject the impurities stuck in the mesh. At the same time, when the ejector is cleaning the blockage at the mesh of the mesh plate, when the extrusion force between the ejector and the impurities stuck in the mesh is greater than the stretching force of the third spring, the ejector is moved downward through the sliding shaft and the slider. At the same time, the buffering work of the third spring is used to avoid excessive extrusion force between the ejector and the impurities stuck in the mesh, which may cause extrusion damage to the ejector, and at the same time, avoid excessive impact force between the ejector and the impurities stuck in the mesh, which may cause excessive extrusion force between the impurities and the inner side of the mesh, which may cause friction damage to the inner wall of the mesh, thereby causing damage to the mesh aperture.

[0009] 5. The present invention sets a contact mechanism. When the conveyor belt is conveying and unloading materials, the conveyor belt and the rubber plate are in contact and moved, so that the rubber plate can clean the side of the conveyor belt. At the same time, when the conveyor belt and the rubber plate are in contact, the rubber plate can drive the moving rod to rotate inside the contact plate, so that the scratch plate can contact and clean the conveyor belt at the same time. By evenly opening square grooves on the scratch plate, the scratch plate can scrape out some processing impurities stuck on the conveyor belt. At the same time, when the extrusion pressure between the scratch plate and the conveyor belt is too large, the contact plate can move downward through the moving rod. At the same time, through the buffering of the fourth spring, it can be avoided that the extrusion pressure between the scratch plate and the conveyor belt is too large, which will cause friction damage to the side of the conveyor belt. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic structural diagram of a solar cell of the present invention; Figure 2 is a schematic structural diagram of the seed layer of the present invention; Figure 3 is a schematic structural diagram of a bus bar of the present invention; Figure 4 It is a schematic diagram of the structure of the conductive wire of the present invention; Figure 5 It is a structural schematic diagram of the connecting line of the present invention; Figure 6 It is a schematic structural diagram of a silicon wafer half-cutting processing device of the present invention; Figure 7 is a cross-sectional view of the present invention; Figure 8 It is a schematic diagram of the structure of the moving parts of the present invention; Fig. 9 It is a structural schematic diagram of the cleaning mechanism of the present invention; Fig.10 It is a schematic diagram of the structure of the collecting component of the present invention; Fig.11 The present invention Fig.10 The structural diagram at A in the middle; Fig.12 It is a structural schematic diagram of the blanking component of the present invention; Fig.13 It is a structural schematic diagram of the contact mechanism of the present invention; In the figure: 1. workbench; 2. laser cutting component; 3. feeding component; 4. moving component; 41. support frame; 42. control mechanism; 43. grabbing mechanism; 44. cleaning mechanism; 441. cleaning frame; 442. sliding frame; 443. telescopic rod; 444. first spring; 445. connecting plate; 446. bending plate; 447. cleaning roller; 448. fixing plate; 449. scraper; 5. unloading component; 51. unloading shell; 52. conveyor belt; 53. contact mechanism; 531. contact frame; 532. contact plate; 533. moving rod; 534. fourth spring; 535. contact shaft; 536. rubber plate; 537. scratch plate; 6. collecting component ; 61. Collection box; 62. Screen; 63. Suction mechanism; 64. Ejection mechanism; 641. Ejection rod; 642. Slider; 643. Sliding shaft; 644. Ejector pin; 645. Third spring; 65. Activated carbon plate; 66. Bracket; 67. Connecting shaft; 68. Second spring; 7. Transmission component; 8. Silicon wafer; 9. Electrode metal seed layer; 10. Electrode bus bar; 11. Electrode conductive wire; 12. Gate line; 13. Connecting line; 14. Tunnel layer; 15. First conductive type semiconductor region; 16. Semiconductor substrate; 17. First passivation film; 18. Second conductive type semiconductor region; 19. Second passivation film A; 20. Second passivation film B. DETAILED DESCRIPTION

[0011] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

[0012] Example 1, using Figure 1 A solar cell according to one embodiment of the present invention is described as follows; like Figure 1 A solar cell according to the present invention comprises: a tunnel layer 14 on a first surface of a semiconductor substrate 16; The first conductive type semiconductor region 15 on the tunnel layer 14 contains semiconductor impurities of the first conductive type; semiconductor impurities of the second conductive type opposite to the first conductive type are located on the second surface of the semiconductor substrate 16 and opposite to the first conductive type semiconductor region 15; The first passivation film 17 on the first conductivity type semiconductor region 15: A battery bus bar parallel to the long side formed on the first passivation film 17 and fixed to the edge by welding or the like; A first electrode formed on the first passivation film 17, connected to the first conductive type semiconductor through the first passivation film 17 and connected to the second surface battery conductive wire through the battery bus bar; A second passivation film A19 and a second passivation film B20 on the second conductivity type semiconductor region 18; The battery metal seed layer formed on the second passivation film B20 may be made of metals such as silver and nickel; A metal conductive wire formed on the second passivation film B20 and completely covering the seed layer and connected to the first surface battery bus bar; It also includes a coated silicon wafer 8, an electrode metal seed layer 9, an electrode bus bar 10, an electrode conductive wire 11, a gate line 12 and a connecting line 13; The electrode metal seed layer 9 and the electrode conductive wire 11 are both arranged on the second surface of the coated silicon wafer 8, the back side of the coated silicon wafer 8 is the first surface, the front side of the coated silicon wafer 8 is the second surface, the electrode bus bar 10, the gate line 12 and the connecting line 13 are arranged on the back side of the silicon wafer 8, and the distribution of the electrode metal seed layer 9 is any one of segmented uniform distribution, whole segment distribution and vertical to the fine gate distribution; Embodiment 2, as Figure 2-Figure 5 A method for preparing a solar cell electrode comprises the following steps: S1: Cutting the coated silicon wafer 8 into half pieces by a cutting device; S2: The coated silicon wafer 8 is screen-printed with a second surface silver seed layer, and an electrode metal seed layer 9 is disposed on the surface of the cell. The electrode metal seed layer 9 is used to improve the contact between the electrode conductive wire 11 and the coated silicon wafer 8; S3: welding the electrode bus bar 10 to the first surface of the coated silicon wafer 8 parallel to the single long side; S4: The electrode conductive wire 11 is a wire that conducts the current longitudinally and transversely. The electrode conductive wire 11 is fixed on the conductive layer by glue and is in contact with the conductive layer, and is connected to the first surface electrode bus bar 10; S5: Use UV light box to cure the glue; S6: Printing grid lines 12 on the first surface, the direction of which intersects with the electrode conductive wires 11, and connecting lines 13 connected to the electrode busbars 10; Embodiment three, as Figure 6-Figure 9 The present invention shows that the silicon wafer cutting device comprises: A workbench 1, a laser cutting component 2 is fixedly connected to the top of the workbench 1, a loading component 3 is fixedly connected to the side of the top of the workbench 1 away from the laser cutting component 2, a transmission component 7 is fixedly connected to the axis of the top of the workbench 1, a collecting component 6 is fixedly connected to the inner side of the workbench 1, and a unloading component 5 is fixedly connected to the side of the top of the workbench 1 away from the loading component 3; A moving component 4, which is used to grab the silicon wafer 8, and the bottom of the moving component 4 is fixedly connected to the top of the workbench 1; The moving component 4 includes a support frame 41, the bottom of the support frame 41 is fixedly connected to the top of the workbench 1, the side of the support frame 41 is slidably connected to a control mechanism 42, the bottom of the control mechanism 42 is symmetrically provided with a grabbing mechanism 43, and the center of the bottom of the control mechanism 42 is fixedly connected to a cleaning mechanism 44; the grabbing mechanism 43 is driven by the control mechanism 42 to move to the left side of the support frame 41, so that the grabbing mechanism 43 grabs the silicon wafer 8 on the feeding component 3, and the silicon wafer 8 is placed on the transmission component 7, and the silicon wafer 8 is driven by the transmission component 7 to the bottom of the laser cutting component 2, so that the laser cutting component 2 cuts the silicon wafer 8 on the transmission component 7, and at the same time, after the laser cutting component 2 cuts the silicon wafer 8, the cut silicon wafer 8 is driven by the transmission component 7 to move to the support frame 41. Under the support frame 41, the two grasping mechanisms 43 are driven to move to the left side of the support frame 41 by the control mechanism 42, so that the grasping mechanism 43 on the right side grasps the silicon wafer 8 after cutting. At the same time, when the grasping mechanism 43 on the right side grasps downward, the grasping mechanism 43 on the left side can grasp the silicon wafer 8 on the loading component 3 at the same time. When the control mechanism 42 drives the grasping mechanism 43 to move to the right side, the grasping mechanism 43 on the right side places the cut silicon wafer 8 on the unloading component 5 for unloading. At the same time, the grasping mechanism 43 on the left side places the silicon wafer 8 on the transmission component 7, and can drive the cleaning mechanism 44 to clean the side of the transmission component 7, so as to avoid residual processing waste on the transmission component 7, thereby interfering with the subsequent cutting work. The cleaning mechanism 44 includes a cleaning frame 441, the top of the cleaning frame 441 is fixedly connected to the bottom of the control mechanism 42, the inner side of the cleaning frame 441 is slidably connected to a sliding frame 442, the middle part of the bottom of the cleaning frame 441 is fixedly connected to a telescopic rod 443, a first spring 444 is sleeved on the telescopic rod 443, the top of the first spring 444 is fixedly connected to the cleaning frame 441, the bottom of the first spring 444 is fixedly connected to the top of a connecting plate 445, the bottom of the sliding frame 442 is fixedly connected to a connecting plate 445, the bottom of the telescopic rod 443 is fixedly connected to the connecting plate 445, the side of the connecting plate 445 is fixedly connected to a bent plate 446, the side of the bent plate 446 away from the connecting plate 445 is rotatably connected to a cleaning roller 447, and the connecting plate 44 A fixed plate 448 is fixedly connected to the side away from the bent plate 446, and a scraper 449 is fixedly connected to the side of the fixed plate 448 away from the mesh plate 62; when the control mechanism 42 drives the grabbing mechanism 43 to move to the left, the control mechanism 42 drives the cleaning frame 441 to move together, so that the cleaning frame 441 drives the fixed plate 448 and the scraper 449 to clean the placement platform on the transmission component 7 through the sliding frame 442, and after the scraper 449 cleans the top of the placement platform, it can drive the cleaning roller 447 to clean and wipe the top of the placement platform through the bent plate 446. By arranging two scrapers 449 at the bottom of the fixed plate 448, and the material of the scraper 449 is rubber, Therefore, when the scraper 449 cleans the top of the placement platform, when one side of the scraper 449 contacts the top of the placement platform for cleaning, the scraper 449 in contact with the top of the placement platform is subjected to the squeeze force, so that the other scraper 449 can be bent and lifted, so that when the control mechanism 42 drives the grasping mechanism 43 to move to the left, the scraper 449 can contact and clean the top of the placement platform, thereby preventing impurities of the silicon wafer 8 after the cutting work from remaining on the top of the placement platform. At the same time, when the control mechanism 42 drives the grasping mechanism 43 to move to the right, the bent plate 446 can drive the scraper 449 to perform secondary reverse cleaning on the top of the placement platform. Two scrapers 449 are provided at the bottom of 48, and the material of the scrapers 449 is rubber, so as to avoid the scrapers 449 from being scratched when cleaning the top of the placement platform for the first time. When the control mechanism 42 drives the grabbing mechanism 43 to move to the right, it will make a second contact with the top of the placement platform, so that the impurities adhered to the scrapers 449 will fall on the top of the placement platform, so that the impurities still remain on the top of the placement platform when the silicon wafer 8 is placed. When the squeezing force between the scrapers 449 and the top of the placement platform is greater than the tensile force of the first spring 444, the connecting plate 445 drives the scrapers 449 to slide upwards on the inner side of the cleaning frame 441, so as to avoid excessive squeezing force between the scrapers 449 and the top of the placement platform. Embodiment 4, as Figure 10-11 It is shown that the silicon wafer cutting device of the present invention is based on the first embodiment; The collecting component 6 includes a collecting box 61, the side of which is fixedly connected to the inner side of the workbench 1, a mesh plate 62 is fixedly connected to the top of the collecting box 61, a suction mechanism 63 is fixedly connected to the bottom of the inner cavity of the collecting box 61, an activated carbon plate 65 is fixedly connected to the top of the suction mechanism 63, a connecting shaft 67 is slidably connected to the bottom of the mesh plate 62, a bracket 66 is fixedly connected to the bottom of the connecting shaft 67, a second spring 68 is sleeved on the connecting shaft 67, the top of the second spring 68 is fixedly connected to the bottom of the mesh plate 62, the bottom of the second spring 68 is fixedly connected to the bracket 66, and the top of the bracket 66 is fixedly connected to the ejection mechanism 64; the laser cutting component 2 cuts the silicon wafer 8 on the transmission component 7, and by opening the suction mechanism 63, the waste chips and waste gas generated during processing can be sucked into the In the collection box 61, the exhaust gas is filtered by the activated carbon plate 65, and the exhaust gas is discharged through the suction mechanism 63 to prevent the exhaust gas generated during the half-cutting process of the silicon wafer 8 from containing silicon dust. When the human body inhales these silicon dusts, they will be deposited in the lungs. Long-term exposure to a high concentration of silicon dust environment will lead to silicosis. At the same time, the suction force generated by the suction mechanism 63 when it is working causes the bracket 66 to move downward through the connecting shaft 67, so that the bracket 66 drives the ejection mechanism 64 to separate from the mesh plate 62. When the collection work is completed and the suction mechanism 63 stops working, the bracket 66 is driven by the stretching of the second spring 68, so that the bracket 66 drives the ejection mechanism 64 to reset the mesh plate 62, thereby preventing the impurities from being blocked in the mesh holes of the mesh plate 62 when the impurities are collected; The ejection mechanism 64 includes an ejection rod 641, which is concentrically arranged with the mesh of the mesh plate 62. The bottom of the ejection rod 641 is fixedly connected to the bracket 66. The inner side of the ejection rod 641 is slidably connected with a slider 642. The side of the slider 642 is fixedly connected with a sliding shaft 643. The side of the sliding shaft 643 is slidably connected with the inner side of the ejection rod 641. The top of the sliding shaft 643 is fixedly connected with an ejector pin 644. The sliding shaft 643 is sleeved with a third spring 645. The top of the third spring 645 is fixedly connected with the ejector pin 644. The bottom of the third spring 645 is fixedly connected with the top of the ejection rod 641. After the collection work is completed, when the suction mechanism 63 stops working, the bracket 66 is driven by the stretching of the second spring 68, so that the bracket 66 drives the ejection rod 641 to perform The ejector pin 644 is driven to eject the impurities stuck in the mesh through the ejector rod 641. When the ejector pin 644 clears the blockage at the mesh of the mesh plate 62, when the extrusion force between the ejector pin 644 and the impurities stuck in the mesh is greater than the tensile force of the third spring 645, the ejector pin 644 is moved downward through the sliding shaft 643 and the slider 642. At the same time, the buffering work of the third spring 645 is performed to avoid excessive extrusion force between the ejector pin 644 and the impurities stuck in the mesh, thereby causing extrusion damage to the ejector pin 644. At the same time, excessive impact force between the ejector pin 644 and the impurities stuck in the mesh is avoided, thereby causing excessive extrusion force between the impurities and the inner side of the mesh, thereby causing friction damage to the inner wall of the mesh, thereby causing damage to the mesh aperture. Embodiment 5, as Figure 12-13 It is shown that the silicon wafer cutting device of the present invention is based on the first embodiment; The unloading component 5 includes an unloading shell 51, the side of which is fixedly connected to the inner side of the workbench 1, the inner side of the unloading shell 51 is rotatably connected to a conveyor belt 52, the inner side of the unloading shell 51 is fixedly connected to a contact mechanism 53, and the contact mechanism 53 is arranged at the bottom of the conveyor belt 52; when the grabbing mechanism 43 places the half-cut silicon wafer 8 on the conveyor belt 52, the conveyor belt 52 drives the silicon wafer 8 to unload the material, and when the conveyor belt 52 is used to transport the cut silicon wafer 8 for a long time, the conveyor belt 52 Some processing debris will remain on the conveyor belt 52, so as to avoid that when the silicon wafer 8 is subsequently conveyed, the impurities adhered to the conveyor belt 52 will interfere with the placement of the silicon wafer 8, thereby interfering with the unloading of the silicon wafer 8. When the conveyor belt 52 is unloading, the conveyor belt 52 and the contact mechanism 53 are in contact and moved, so that the contact mechanism 53 can clean the side of the conveyor belt 52, so as to avoid that when the conveyor belt 52 is used for a long time to transport and unload the cut silicon wafer 8, a large amount of processing impurities will remain on the side of the conveyor belt 52; The contact mechanism 53 includes a contact frame 531, the side of the contact frame 531 is fixedly connected to the inner side of the material discharge shell 51, the inner side of the contact frame 531 is slidably connected with a moving rod 533, the top of the moving rod 533 is fixedly connected with a contact plate 532, a fourth spring 534 is sleeved on the moving rod 533, the top of the fourth spring 534 is fixedly connected to the contact plate 532, the bottom of the fourth spring 534 is fixedly connected to the inner side of the contact frame 531, the inner side of the contact plate 532 is rotatably connected with a contact shaft 535, the side of the contact shaft 535 is fixedly connected with a rubber plate 536, the side of the contact shaft 535 away from the rubber plate 536 is fixedly connected with a scratch plate 537, and the side of the scratch plate 537 is in contact with the conveyor belt 52; when the conveyor belt 52 is performing the conveying and unloading work, the conveyor belt 52 is in contact with the rubber plate 536. The rubber plate 533 is moved to the side of the conveyor belt 52 to clean the conveyor belt 52. At the same time, when the conveyor belt 52 contacts the rubber plate 536, the rubber plate 536 can drive the moving rod 533 to rotate inside the contact plate 532, so that the scraping plate 537 can contact and clean the conveyor belt 52 at the same time. By evenly opening square grooves on the scraping plate 537, the scraping plate 537 can scrape out some processing impurities stuck on the conveyor belt 52. At the same time, when the extrusion pressure between the scraping plate 537 and the conveyor belt 52 is too large, the contact plate 532 can be moved downward by the moving rod 533. At the same time, the buffering of the fourth spring 534 can prevent the extrusion pressure between the scraping plate 537 and the conveyor belt 52 from being too large, which will cause friction damage to the side of the conveyor belt 52. The specific workflow is as follows: When working, the loading component 3 is opened, and the silicon wafer 8 on the loading component 3 is grabbed onto the transmission component 7 by the moving component 4, and the silicon wafer 8 is driven to the bottom of the laser cutting component 2 by the transmission component 7, and the silicon wafer 8 is cut in half by the laser cutting component 2. During the cutting process, the waste chips and waste gas generated in the half-cutting of the silicon wafer 8 can be collected by opening the collecting component 6. After the silicon wafer 8 is cut in half, the cut silicon wafer 8 is brought to the unloading component 5 by the transmission component 7, and the half-cut silicon wafer 8 is unloaded and transported by the unloading component 5; The control mechanism 42 drives the grasping mechanism 43 to move to the left side of the support frame 41, so that the grasping mechanism 43 grasps the silicon wafer 8 on the feeding component 3, and then puts the silicon wafer 8 on the transmission component 7, and drives the silicon wafer 8 to the bottom of the laser cutting component 2 through the transmission component 7, so that the laser cutting component 2 cuts the silicon wafer 8 on the transmission component 7. After the laser cutting component 2 cuts the silicon wafer 8, the transmission component 7 drives the cut silicon wafer 8 to move to the bottom of the support frame 41, and at the same time, the control mechanism 42 drives the two grasping mechanisms 43 to move to the left side of the support frame 41, so that the grasping mechanism 43 on the right side The mechanism 43 grabs the silicon wafer 8 after cutting. When the grabbing mechanism 43 on the right side grabs downward, the grabbing mechanism 43 on the left side can grab the silicon wafer 8 on the loading component 3 at the same time. When the control mechanism 42 drives the grabbing mechanism 43 to move to the right, the grabbing mechanism 43 on the right side places the cut silicon wafer 8 on the unloading component 5 for unloading. At the same time, the grabbing mechanism 43 on the left side places the silicon wafer 8 on the transmission component 7, and can drive the cleaning mechanism 44 to clean the side of the transmission component 7, so as to avoid residual processing waste on the transmission component 7, which will interfere with the subsequent cutting work. When the control mechanism 42 drives the grabbing mechanism 43 to move to the left, the control mechanism 42 drives the cleaning frame 441 to move together, so that the cleaning frame 441 drives the fixed plate 448 and the scraper 449 to clean the placement platform on the transmission component 7 through the sliding frame 442. At the same time, after the scraper 449 cleans the top of the placement platform, it can drive the cleaning roller 447 to clean and wipe the top of the placement platform through the curved plate 446. By arranging two scrapers 449 at the bottom of the fixed plate 448, and the material of the scraper 449 is rubber, when the scraper 449 cleans the top of the placement platform, one side of the scraper 449 contacts the top of the placement platform for cleaning, and the scraper 449 in contact with the top of the placement platform is subjected to the extrusion force, so that the other scraper 449 can be bent and lifted, so that when the control mechanism 42 drives the grabbing mechanism 43 to move to the left, the scraper 449 can contact and clean the top of the placement platform, thereby In order to prevent the impurities of the silicon wafer 8 after the cutting work from remaining on the top of the placement platform, when the control mechanism 42 drives the grabbing mechanism 43 to move to the right, the bent plate 446 can drive the scraper 449 to perform secondary reverse cleaning on the top of the placement platform. Two scrapers 449 are arranged at the bottom of the fixed plate 448, and the scraper 449 is made of rubber material, so as to prevent the scraper 449 from being scratched for the first time when the control mechanism 42 drives the grabbing mechanism 43 to move to the right, so that the impurities adhered to the scraper 449 will fall on the top of the placement platform, so that the impurities still remain on the top of the placement platform when the silicon wafer 8 is placed. When the extrusion force between the scraper 449 and the top of the placement platform is greater than the tensile force of the first spring 444, the connecting plate 445 drives the scraper 449 to slide upward on the inner side of the cleaning frame 441, so as to prevent the extrusion force between the scraper 449 and the top of the placement platform from being too large. The laser cutting component 2 cuts the silicon wafer 8 on the transmission component 7. By opening the suction mechanism 63, the waste chips and waste gas generated during the processing can be sucked into the collection box 61 through the mesh plate 62. At the same time, the waste gas is filtered through the activated carbon plate 65, and the waste gas is discharged through the suction mechanism 63 to prevent the waste gas generated during the half-cutting process of the silicon wafer 8 from containing silicon dust. When the human body inhales these silicon dusts, they will be deposited in the lungs. Long-term exposure to a high concentration of silicon dust environment will cause silicosis. At the same time, the suction force generated by the suction mechanism 63 when it is working causes the bracket 66 to move downward through the connecting shaft 67, so that the bracket 66 drives the ejection mechanism 64 to separate from the mesh plate 62. When the collection work is completed and the suction mechanism 63 stops working, the bracket 66 is driven by the stretching of the second spring 68, so that the bracket 66 drives the ejection mechanism 64 to reset the mesh plate 62, thereby preventing the impurities from being blocked in the mesh holes of the mesh plate 62 when the impurities are collected; After the collection work is completed, when the suction mechanism 63 stops working, the bracket 66 is driven by the stretching of the second spring 68, so that the bracket 66 drives the ejection rod 641 to reset the mesh plate 62, and at the same time, the ejection rod 641 drives the ejector pin 644 to eject the impurities stuck in the mesh. At the same time, when the ejector pin 644 cleans the blockage at the mesh of the mesh plate 62, when the extrusion force between the ejector pin 644 and the impurities stuck in the mesh is greater than the stretching force of the third spring 645, the ejector pin 644 moves downward through the sliding shaft 643 and the slider 642, and at the same time, the buffering work of the third spring 645 is used to avoid excessive extrusion force between the ejector pin 644 and the impurities stuck in the mesh, thereby causing extrusion damage to the ejector pin 644, and at the same time, avoid excessive impact force between the ejector pin 644 and the impurities stuck in the mesh, thereby causing excessive extrusion force between the impurities and the inner side of the mesh, thereby causing friction damage to the inner wall of the mesh, thereby causing damage to the mesh aperture. When the grabbing mechanism 43 places the half-cut silicon wafer 8 on the conveyor belt 52, the conveyor belt 52 is used to transport and drive the silicon wafer 8 for unloading. At the same time, when the conveyor belt 52 is used to transport and unload the cut silicon wafer 8 for a long time, some processing debris will remain on the conveyor belt 52, thereby preventing the impurities adhering to the conveyor belt 52 from interfering with the placement position of the silicon wafer 8 during the subsequent conveying of the silicon wafer 8, thereby interfering with the unloading of the silicon wafer 8. When the conveyor belt 52 is unloading, the conveyor belt 52 is moved in contact with the contact mechanism 53, so that the contact mechanism 53 can clean the side of the conveyor belt 52, thereby preventing a large amount of processing impurities from remaining on the side of the conveyor belt 52 when the conveyor belt 52 is used to transport and unload the cut silicon wafer 8 for a long time. When the conveyor belt 52 is conveying and unloading materials, the conveyor belt 52 and the rubber plate 536 are in contact and moved, so that the rubber plate 536 can clean the side of the conveyor belt 52. At the same time, when the conveyor belt 52 and the rubber plate 536 are in contact, the rubber plate 536 can drive the moving rod 533 to rotate inside the contact plate 532, so that the scratch plate 537 can contact and clean the conveyor belt 52 at the same time. By evenly opening square grooves on the scratch plate 537, the scratch plate 537 can scrape out some processing impurities stuck on the conveyor belt 52. At the same time, to avoid the extrusion pressure between the scratch plate 537 and the conveyor belt 52 being too large, the contact plate 532 can be moved downward by the moving rod 533. At the same time, through the buffering of the fourth spring 534, it can avoid the extrusion pressure between the scratch plate 537 and the conveyor belt 52 being too large, which will cause friction damage to the side of the conveyor belt 52.

[0013] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A solar cell, characterized in that: include: a tunnel layer (14) on a first surface of a semiconductor substrate (16); A first conductive type semiconductor region (15) on the tunnel layer (14) contains semiconductor impurities of the first conductive type; Semiconductor impurities of a second conductivity type opposite to the first conductivity type are located on the second surface of the semiconductor substrate (16) and are opposite to the first conductivity type semiconductor region (15); A first passivation film (17) on the first conductivity type semiconductor region (15): A battery bus bar parallel to the long side formed on the first passivation film (17) and fixed to the edge by welding or the like; A first electrode formed on the first passivation film (17), connected to the first conductive type semiconductor through the first passivation film (17) and connected to the second surface battery conductive wire through a battery bus bar; A second passivation film A (19) and a second passivation film B (20) on the second conductivity type semiconductor region (18); A battery metal seed layer formed on the second passivation film B (20), the material of which may be silver, nickel or other metals; A metal conductive wire formed on the second passivation film B (20) and completely covering the seed layer and connected to the first surface battery bus bar; It also includes a coated silicon wafer (8), an electrode metal seed layer (9), an electrode bus bar (10), an electrode conductive wire (11), a gate wire (12) and a connecting wire (13); The electrode metal seed layer (9) and the electrode conductive wire (11) are both arranged on the second surface of the coated silicon wafer (8); the back side of the coated silicon wafer (8) is the first surface; the front side of the coated silicon wafer (8) is the second surface; the electrode bus bar (10), the gate line (12) and the connecting line (13) are arranged on the back side of the silicon wafer (8); and the distribution of the electrode metal seed layer (9) is any one of segmented uniform distribution, whole segment distribution and vertical to fine gate distribution.

2. A method for preparing a solar cell electrode, characterized in that: The steps include: S1: Cutting the coated silicon wafer (8) into half pieces using a cutting device; S2: a second surface silver seed layer is screen-printed on the coated silicon wafer (8), and an electrode metal seed layer (9) is arranged on the surface of the battery cell, wherein the electrode metal seed layer (9) is used to improve the contact between the electrode conductive wire (11) and the coated silicon wafer (8); S3: welding the electrode bus bar (10) on the first surface of the coated silicon wafer (8) parallel to the single long side; S4: The electrode conductive wire (11) is a wire that conducts current longitudinally and transversely, and the electrode conductive wire (11) is fixed to the conductive layer by glue so that the conductive wire (11) contacts the conductive layer and is connected to the first surface electrode bus bar (10); S5: Use UV light box to cure the glue; S6: Printing grid lines (12) on the first surface, with the direction of the grid lines intersecting with the electrode conductive wires (11), and connecting lines (13) connected to the electrode bus bars (10).

3. The method for preparing a solar cell electrode according to claim 2, characterized in that: Step S3 of welding the electrode bus bar (10) to the first surface of the coated silicon wafer parallel to a single long side comprises the following steps: S301: preparing electrode bus bars (10) that meet the requirements, welding materials, a laser welding machine, and a fixture and positioning tool for fixing the silicon wafer (8) and the electrode bus bars (10); S302: Positioning the electrode bus bar (10): according to the design requirements of the battery cell, the welding position of the electrode bus bar (10) on the first surface of the silicon wafer (8) is determined, which should be parallel to the long side. With the help of a positioning tool, the electrode bus bar (10) is accurately placed at a specified position on the first surface of the silicon wafer (8) to ensure that it is tightly fitted and straight; S303: Laser welding operation: accurately place the welding piece at the contact part to ensure close fit, set the laser power, pulse frequency and other parameters according to the material, turn on the equipment, observe whether the welding has any defects, and re-weld after timely handling if there are any problems; S304: Inspection and processing after welding, checking whether there are defects such as cold welding and desoldering at the welding position, and placing the silicon wafer (8) in a specified area to wait for subsequent steps.

4. The method for preparing a solar cell electrode according to claim 3, characterized in that: The laser welding operation in step S303 includes the following steps: S3031: placing solder, and accurately placing the preformed solder sheet at the contact position between the electrode bus bar (10) and the first surface of the silicon wafer (8), ensuring that the preformed solder sheet is tightly fitted with the electrode bus bar (10) without any gaps, and the size of the preformed solder sheet matches the soldering position; S3032: setting welding parameters according to factors such as the electrode bus bar (10), silicon wafer (8) material, welding sheet thickness and equipment performance. When welding the electrode bus bar (10) and the coated silicon wafer (8), use a 0.1-0.15 mm thick welding sheet, set the laser power to 100-200 W, the pulse frequency to 10-20 kHz, the welding speed to 1-3 / s, and adjust the focus position to the center of the welding part; S3033: Turn on the equipment and irradiate the welding part according to the set parameters. Observe closely during welding. If the welding piece is not melted well or there is a porosity defect, stop welding in time and adjust the parameters.

5. The method for preparing a solar cell electrode according to claim 2, characterized in that: The electrode metal seed layer (9) is composed of a plurality of metal printing dots. The electrode metal seed layer (9) has a width of 3-30 um and a height of 2-15 um. The mesh number of the printing screen is 400-800 meshes, and the wire diameter is 3-30 μm. The yarn thickness is 3-30 μm, and the film thickness is 2-10 μm. The printing line width is 5-15 μm. The electrode busbar (10) has a width of 0.1-3 mm. The glue is any one of a light-curing glue and a thermosetting glue. The metal conductive wire can be made of one or more of silver, copper, aluminum, nickel, gold, calcium, tungsten, zinc, lithium, etc. The curing operation in step S5 is performed by any one of a UV light box and a heat box.

6. The method for preparing a solar cell electrode according to claim 2, characterized in that: The cutting device comprises: A workbench (1), wherein a laser cutting component (2) is fixedly connected to the top of the workbench (1), a loading component (3) is fixedly connected to the side of the top of the workbench (1) away from the laser cutting component (2), a transmission component (7) is fixedly connected to the axis of the top of the workbench (1), a collecting component (6) is fixedly connected to the inner side of the workbench (1), and a unloading component (5) is fixedly connected to the side of the top of the workbench (1) away from the loading component (3); A moving component (4), the moving component (4) being used to grasp the silicon wafer (8), the bottom of the moving component (4) being fixedly connected to the top of the workbench (1); The moving component (4) comprises a support frame (41), the bottom of the support frame (41) is fixedly connected to the top of the workbench (1), the side of the support frame (41) is slidably connected to a control mechanism (42), the bottom of the control mechanism (42) is symmetrically provided with a grasping mechanism (43), and the center of the bottom of the control mechanism (42) is fixedly connected to a cleaning mechanism (44); The cleaning mechanism (44) comprises a cleaning frame (441), the top of the cleaning frame (441) is fixedly connected to the bottom of the control mechanism (42), the inner side of the cleaning frame (441) is slidably connected to a sliding frame (442), the middle part of the bottom of the cleaning frame (441) is fixedly connected to a telescopic rod (443), the telescopic rod (443) is sleeved with a first spring (444), the top of the first spring (444) is fixedly connected to the cleaning frame (441), and the bottom of the first spring (444) is fixedly connected to the top of the connecting plate (445). The bottom of the sliding frame (442) is fixedly connected to a connecting plate (445), the bottom of the telescopic rod (443) is fixedly connected to the connecting plate (445), the side of the connecting plate (445) is fixedly connected to a bent plate (446), a side of the bent plate (446) away from the connecting plate (445) is rotatably connected to a cleaning roller (447), a side of the connecting plate (445) away from the bent plate (446) is fixedly connected to a fixed plate (448), and a side of the fixed plate (448) away from the mesh plate (62) is fixedly connected to a scraper (449).

7. The method for preparing a solar cell electrode according to claim 6, characterized in that: The cutting device comprises: the collecting component (6) comprises a collecting box (61), the side of the collecting box (61) is fixedly connected to the inner side of the workbench (1), the top of the collecting box (61) is fixedly connected to a mesh plate (62), the bottom of the inner cavity of the collecting box (61) is fixedly connected to an air suction mechanism (63), the top of the air suction mechanism (63) is fixedly connected to an activated carbon plate (65), the bottom of the mesh plate (62) is slidably connected to a connecting shaft (67), the bottom of the connecting shaft (67) is fixedly connected to a bracket (66), a second spring (68) is sleeved on the connecting shaft (67), the top of the second spring (68) is fixedly connected to the bottom of the mesh plate (62), the bottom of the second spring (68) is fixedly connected to the bracket (66), and the top of the bracket (66) is fixedly connected to an ejection mechanism (64).

8. The method for preparing a solar cell electrode according to claim 7, characterized in that: The cutting device comprises: the ejection mechanism (64) comprises an ejection rod (641), the ejection rod (641) is arranged concentrically with the mesh of the mesh plate (62), the bottom of the ejection rod (641) is fixedly connected to the bracket (66), the inner side of the ejection rod (641) is slidably connected to a slider (642), the side of the slider (642) is fixedly connected to a sliding shaft (643), the side of the sliding shaft (643) is slidably connected to the inner side of the ejection rod (641), the top of the sliding shaft (643) is fixedly connected to an ejector pin (644), the sliding shaft (643) is sleeved with a third spring (645), the top of the third spring (645) is fixedly connected to the ejector pin (644), and the bottom of the third spring (645) is fixedly connected to the top of the ejection rod (641).

9. The method for preparing a solar cell electrode according to claim 6, characterized in that: The cutting device comprises: the blanking component (5) comprises a blanking shell (51), the side surface of the blanking shell (51) is fixedly connected to the inner side of the workbench (1), the inner side of the blanking shell (51) is rotatably connected to a conveyor belt (52), the inner side of the blanking shell (51) is fixedly connected to a contact mechanism (53), and the contact mechanism (53) is arranged at the bottom of the conveyor belt (52).

10. The method for preparing a solar cell electrode according to claim 9, characterized in that: The cutting device comprises: the contact mechanism (53) comprises a contact frame (531), the side surface of the contact frame (531) is fixedly connected to the inner side of the material discharge shell (51), the inner side of the contact frame (531) is slidably connected to a moving rod (533), the top of the moving rod (533) is fixedly connected to a contact plate (532), a fourth spring (534) is sleeved on the moving rod (533), the top of the fourth spring (534) is fixedly connected to the contact plate (532), the bottom of the fourth spring (534) is fixedly connected to the inner side of the contact frame (531), the inner side of the contact plate (532) is rotatably connected to a contact shaft (535), the side surface of the contact shaft (535) is fixedly connected to a rubber plate (536), the side of the contact shaft (535) away from the rubber plate (536) is fixedly connected to a scratch plate (537), and the side surface of the scratch plate (537) is in contact with the conveyor belt (52).

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