Full-opening solar cell screen printing plate

Abstract

The utility model relates to the field of screen printing technology, and particularly discloses a full-opening solar cell screen printing plate which comprises a screen frame, a polyester screen and a screen printing metal net. The silk-screen metal net comprises a silk screen and a PI film pasted on the silk screen, silk drawing is conducted on the silk screen corresponding to a printing area to form a grid line area used for printing grid lines, a grid line groove used for printing the grid lines is formed in the PI film corresponding to the grid line area, the grid line groove is formed in the direction perpendicular to the steel wire drawing direction of silk drawing, and the grid line groove is located between every two adjacent steel wires. The grid line areas are formed in the printing area of the silk screen through silk drawing, the grid line grooves are formed in the positions, corresponding to the grid line areas, of the PI film, and the grid line grooves are perpendicular to the drawn-out steel wires and located between every two adjacent steel wires, so that machining of the grid line grooves is not affected by the wire diameter of the silk screen, the machining precision can be effectively improved, and the machining efficiency is improved. Therefore, the printing precision of the grid line is improved.

Description

Technical Field

[0001] This application relates to the field of screen printing technology, and in particular to a fully open solar cell screen printing stencil. Background Art

[0002] Screen printing technology plays a crucial role in the manufacturing of solar cells. It is mainly applied to the formation of electrodes of the cells. By printing very fine circuits on the front and back of the silicon wafers, the photo-generated electrons are led out of the cells. This process involves pressing a conductive paste containing metal through the mesh holes of the screen onto the silicon wafer to form a circuit or an electrode, which plays a key role in controlling the production cost and improving the electrical performance of the solar cells.

[0003] In the related art, when manufacturing a screen printing stencil, it is necessary to first perform laser cutting on the corresponding printing area of the screen, then extract multiple warp threads in the printing area, then paste a PI film on the screen, and finally complete the pattern making through a laser film opening process on the PI film in the printing area.

[0004] It is found in actual production that with the continuous development of solar cells, the requirements for the printing accuracy of grid lines are getting higher and higher, and the required line width of the grid lines is also getting smaller; when meeting the printing requirements, a finer wire diameter of the screen is required to meet the requirements for printing accuracy; and most of the current screens with finer wire diameters still rely on imports, resulting in higher costs. Summary of the Invention

[0005] In order to reduce the production cost, this application provides a fully open solar cell screen printing stencil, which can effectively improve the processing accuracy.

[0006] A fully open solar cell screen printing stencil provided by this application adopts the following technical solution:

[0007] A fully open solar cell screen printing stencil includes a screen frame, a polyester screen, and a screen printing metal screen; the screen printing metal screen includes a screen and a PI film pasted on the screen. A grid line area for printing grid lines is formed by extracting wires in the corresponding printing area of the screen. Grid slots for printing grid lines are opened on the PI film corresponding to the grid line area. The grid slots are opened perpendicular to the direction of the wires extracted, and the grid slots are located between two adjacent wires.

[0008] By adopting the above technical scheme, wire drawing is performed in the printing area of ​​the silk screen to form a gate line area, and a gate line groove is opened at a position corresponding to the gate line area on the PI film. The gate line groove is perpendicular to the drawn steel wire and is located between two adjacent steel wires, so that the processing of the gate line groove is not affected by the wire diameter of the silk screen; at the same time, the processing accuracy of the gate line groove can be effectively improved, thereby improving the printing accuracy of the gate line, making the printed gate line thinner, reducing the shielding of the gate line to sunlight, and improving the photoelectric conversion efficiency of the battery cell; the fine grid line can achieve a denser layout, reduce the conduction distance of the current on the fine grid, and effectively reduce the series resistance of the component, thereby reducing power loss and improving the fill factor and output power of the battery.

[0009] Optionally, the wires drawn out in the grid line area are warps, and the grid line grooves are opened parallel to the weft direction.

[0010] By adopting the above technical solution, the grid line grooves are opened parallel to the weft direction. During processing, the scraper moves the slurry along the weft direction, which can reduce the influence of the scraper on the accuracy of the grid line grooves.

[0011] Optionally, the gate line region and the gate line groove may be provided in multiple stages as required.

[0012] By adopting the above technical solution, when processing the screen, the number of grid line areas and grid line grooves can be set according to printing needs, which facilitates processing.

[0013] Optionally, the width of the grid line groove can be adjusted by moving two adjacent steel wires.

[0014] By adopting the above technical solution, when processing the screen, the adjacent steel wires on both sides of the grid line groove can be moved away from or close to each other under a microscope, thereby making the width of the grid line groove larger or smaller, thereby achieving the purpose of adjusting the width of the grid line groove, which can effectively improve the printing accuracy of the grid line.

[0015] Optionally, a reinforcing adhesive strip is adhered and fixed to the connection between the polyester mesh and the mesh frame.

[0016] By adopting the above technical solution and pasting a reinforcing rubber strip between the polyester mesh and the mesh frame, the connection strength between the polyester mesh and the mesh frame can be effectively improved.

[0017] In summary, the present application includes at least one of the following beneficial technical effects:

[0018] 1. A grid line area is formed by drawing wires in the printing area of ​​the screen, and a grid line groove is opened at the position corresponding to the grid line area on the PI film. The grid line groove is perpendicular to the drawn steel wire and is located between two adjacent steel wires, so that the processing of the grid line groove is not affected by the wire diameter of the screen. At the same time, the processing accuracy of the grid line groove can be effectively improved, thereby improving the printing accuracy of the grid line, making the printed grid line thinner, reducing the grid line from blocking sunlight, and improving the photoelectric conversion efficiency of the battery cell. The fine grid line can achieve a denser layout, reducing the conduction distance of the current on the fine grid, effectively reducing the series resistance of the component, thereby reducing power loss and improving the fill factor and output power of the battery;

[0019] 2. When processing the screen, you can move the adjacent steel wires on both sides of the grid line groove under a microscope to make the steel wires move away from or close to each other, thereby making the width of the grid line groove larger or smaller, so as to achieve the purpose of adjusting the width of the grid line groove, which can effectively improve the printing accuracy of the grid line. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application;

[0021] Figure 2 It is a schematic diagram of the processing of the screen in the embodiment of the present application;

[0022] Figure 3 It is a schematic diagram of the processing of the PI film of the embodiment of the present application.

[0023] Figure numerals: 1, silk screen metal mesh; 11, silk screen; 111, grid line area; 12, PI film; 121, grid line groove; 2, screen frame; 3, polyester mesh; 4, hot melt adhesive; 5, reinforcement adhesive strip. DETAILED DESCRIPTION

[0024] On the one hand, the present application embodiment discloses a full-opening solar cell screen printing screen, referring to Figure 1 , including a screen frame 2, a polyester screen 3 and the above-mentioned silk-screen metal screen 1, the polyester screen 3 is pasted and fixed on the screen frame 2, the silk-screen metal screen 1 is located in the middle of the polyester screen 3, and the surrounding side of the silk-screen metal screen 1 is fixed to the polyester screen 3 by hot-melt adhesive 4; a reinforcing adhesive strip 5 is pasted and fixed at the connection between the polyester screen 3 and the screen frame 2, which can effectively improve the connection strength between the polyester screen 3 and the screen frame 2.

[0025] Reference Figure 2 and Figure 3 The silk-screen metal mesh 1 comprises a silk screen 11 and a PI film 12 fixed on the silk screen 11. A gate line area 111 for printing gate lines is formed by drawing wire in the area corresponding to printing on the silk screen 11. A gate line groove 121 for printing gate lines is opened at a position corresponding to the gate line area 111 on the PI film 12. During the printing process, the slurry leaks from the gate line groove 121 onto the silicon wafer to form gate lines.

[0026] During processing, firstly, the warp lines of the printing area are cut and drawn out by laser cutting on the screen 11 to form the grid line area 111; then, the PI film 12 is fixed on the screen 11, and then the grid line grooves 121 are opened at the positions corresponding to the grid line areas 111 on the PI film 12 by laser engraving, and the grid line grooves 121 are opened parallel to the weft direction.

[0027] After the gate line groove 121 is processed, the groove width of the gate line groove 121 needs to be checked under a microscope. The groove width of the gate line groove 121 can be adjusted by moving the metal wires on both sides of the gate line groove 121 to make the metal wires move closer to or farther away from each other, so that the width of the gate line groove 121 meets the requirements.

[0028] The implementation principle of a fully-open solar cell silk-screen screen disclosed in the embodiment of the present application is as follows: a grid line area 111 is formed by drawing wires in the printing area of ​​the silk screen 11, and a grid line groove 121 is opened at a position corresponding to the grid line area 111 on the PI film 12, and the grid line groove 121 is located between two adjacent steel wires, so that the processing of the grid line groove 121 is not affected by the wire diameter of the silk screen 11, and a higher processing accuracy can be achieved by using a silk screen 11 with a larger wire diameter. At the same time, the grid line groove 121 can be processed to be thinner, so that the printed grid line can be made thinner, reducing the grid line from blocking sunlight and improving the photoelectric conversion efficiency of the battery cell; and the fine grid line can achieve a denser layout, reducing the conduction distance of the current on the fine grid, effectively reducing the series resistance of the component, thereby reducing power loss and improving the fill factor and output power of the battery.

[0029] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A full-opening solar cell screen printing screen, characterized in that: The invention comprises a screen frame (2), a polyester screen (3) and a screen printing metal screen (1); the screen printing metal screen (1) comprises a screen (11) and a PI film (12) pasted on the screen (11); a grid line area (111) for printing grid lines is formed by drawing wires on the screen (11) corresponding to the printing area; a grid line groove (121) for printing grid lines is opened on the PI film (12) corresponding to the grid line area (111); the grid line groove (121) is opened perpendicular to the direction of the steel wire for drawing and adjusting the wires; and the grid line groove (121) is located between two adjacent steel wires.

2. A fully-open solar cell screen printing screen according to claim 1, characterized in that: The grid line area (111) extracts the warp lines, and the grid line grooves (121) are opened parallel to the weft line direction.

3. The full-opening solar cell screen printing screen according to claim 1, characterized in that: The gate line region (111) and the gate line groove (121) may be provided in multiple layers as required.

4. The full-opening solar cell screen printing screen according to claim 1, characterized in that: The width of the grid line groove (121) can be adjusted by moving two adjacent steel wires.

5. The full-opening solar cell screen printing screen according to claim 1, characterized in that: A reinforcing rubber strip (5) is glued and fixed at the connection between the polyester net (3) and the net frame (2).

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