Screen printing plate structure

Abstract

The screen printing plate structure comprises a screen printing plate body and a bearing piece, the screen printing plate body comprises a first surface close to a battery piece and a second surface away from the battery piece, the screen printing plate body comprises a plate body and an opening formed in the plate body, the opening is through in the thickness direction of the plate body, and the bearing piece is arranged on the plate body. The openings are used for slurry to penetrate through, so that the slurry forms an electrode on the battery piece, the openings comprise a main grid opening and a lap joint opening, the main grid opening is used for forming a main grid, the lap joint opening is communicated with the main grid opening, and the lap joint opening is used for forming a lap joint structure on the main grid; the bearing piece is arranged on the first surface and corresponds to the lap joint opening, and the bearing piece is configured to be used for bearing part of the slurry when the slurry is laid, enabling the slurry to penetrate when the slurry is impressed, and having enough height to bear solder strip offset at the lap joint structure when the solder strip passes through the main grid, so that the yield of the battery piece is improved.

Description

Technical Field

[0001] This application relates to the field of solar cell technology, and more particularly to a screen printing structure. Background Technology

[0002] In the electrode production process of solar cells, paste is usually printed onto the solar cell using a screen printing structure to form electrodes. Existing electroforming fully open screen printing plates use steel plates for the film layer. Multiple openings are cut into the steel plate according to the shape of the electrode. The paste is printed onto the solar cell through the openings of the steel plate. Since each opening is an integral open structure, the height and undulation of the main grid or the auxiliary overlapping parts on the main grid are basically the same during the printing process. However, when welding the solder strips on the main grid, if the paste height of other overlapping parts on the main grid is insufficient, it is easy to cause the solder strips on the main grid to break, which will reduce the efficiency of the solar cell or even make it impossible to manufacture the module. Utility Model Content

[0003] This application discloses a screen structure that allows the overlapping structure on the main grid to be thicker than the paste on the main grid on the cell, ensuring more reliable contact and welding when the solder strip is welded to the main grid, thereby improving the yield of the cell.

[0004] To achieve the above objectives, this application discloses a screen printing structure for printing electrodes on solar cells, comprising:

[0005] A wire mesh body includes a first surface close to the solar cell and a second surface away from the solar cell. The wire mesh body includes a plate and an opening provided on the plate. The opening extends along the thickness direction of the plate and is used for paste to pass through, so that the paste forms electrodes on the solar cell. The opening includes a main grid opening and an overlap opening. The main grid opening is used to form a main grid, and the overlap opening is connected to the main grid opening to form an overlap structure on the main grid.

[0006] A support member is disposed on the first surface and corresponding to the overlap opening. The support member is configured to support part of the slurry when the slurry is laid and to allow the slurry to pass through when the slurry is imprinted.

[0007] In one possible implementation, the support member includes a plurality of spaced-apart first steel wires that cross the lap opening and whose ends are respectively connected to the plate.

[0008] In one possible implementation, multiple of the first steel wires are arranged in parallel.

[0009] In one possible implementation, the support member further includes a plurality of second steel wires perpendicular to the first steel wire, the second steel wires being connected to the first steel wire to form a wire mesh.

[0010] In one possible implementation, the main grid opening extends along a first direction, and the first wire extends along the first direction.

[0011] In one possible implementation, the overlap opening includes a sub-gate overlap opening and a pad opening. The sub-gate overlap opening is used to form a connection structure between the main gate and the sub-gate, and the pad opening is used to form a pad. The support member includes a first support member and a second support member. The first support member is disposed corresponding to the sub-gate overlap opening, and the second support member is disposed corresponding to the pad opening.

[0012] In one possible implementation, the sub-gate overlap openings include a plurality of sub-gate overlap openings that are perpendicular to the main gate opening and are evenly distributed along the first direction. The first support members include a plurality of first support members that correspond one-to-one with the plurality of sub-gate overlap openings.

[0013] In one possible implementation, the main gate opening includes multiple sets, each set of the main gate opening is used to form a main gate, each set of the main gate opening is corresponding to a pad opening, and the second support includes multiple second support members, each of which corresponds to a pad opening.

[0014] In one possible implementation, the overlap opening further includes branch openings located on both sides of the pad opening, the branch openings being parallel to the main gate opening, the branch openings being used to form branch gate lines at the ends of the main gate, the overlap opening further including branch overlap openings perpendicularly disposed on the branch openings, the branch overlap openings being used to form a connection structure between the branch gate lines and the sub-gate, and the support member including a third support member, the third support member being disposed corresponding to the branch overlap opening.

[0015] In one possible implementation, the branch overlap opening includes multiple branch overlap openings, which are perpendicular to the branch opening and are evenly distributed along the first direction. The third support includes multiple third support members, and the multiple first support members correspond one-to-one with the multiple sub-grid overlap openings.

[0016] Compared with the prior art, the beneficial effects of this application are as follows:

[0017] In this application, the wire mesh body includes a first surface close to the solar cell and a second surface away from the solar cell. The wire mesh body includes a plate and an opening provided on the plate. The opening extends along the thickness direction of the plate and is used for paste to pass through. Therefore, after the paste passes through the opening and reaches the solar cell, the paste forms electrodes on the solar cell. The opening includes a main grid opening and an overlap opening. The main grid opening is used to form the main grid on the solar cell, and the overlap opening communicates with the main grid opening to form an overlap structure on the main grid. This application further provides a support member on the first surface of the wire mesh body close to the solar cell, and simultaneously overlaps the support member accordingly. The opening is designed so that the support is configured to support the paste during paste laying and allow the paste to pass through during printing. Thus, during paste laying, because the support can support the paste, more paste can pass through the overlap opening compared to the main grid opening during printing. This results in a thicker overlap structure on the main grid compared to the paste on the cell. When the solder ribbon passes through the main grid, the overlap structure on the main grid has sufficient height to accommodate the solder ribbon offset, ensuring more reliable contact and welding. This solves the welding defects caused by excessively low grid lines in fully open screen printing and improves cell yield. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 One of the structural schematic diagrams of a screen printing plate structure provided in this embodiment of the present utility model;

[0020] Figure 2 A second schematic diagram of a screen printing structure provided for an embodiment of this utility model;

[0021] Figure 3 A third schematic diagram of a screen printing structure provided for an embodiment of this utility model;

[0022] Figure 4 A schematic diagram of a support member for a screen structure provided in an embodiment of this utility model;

[0023] Figure 5 This is one of the structural diagrams of a screen printing plate structure in use, provided by an embodiment of the present utility model;

[0024] Figure 6 This is the second schematic diagram of a screen printing structure in use, provided as an embodiment of the present utility model.

[0025] Explanation of reference numerals in the attached figures:

[0026] 10-Grid body; 11-Panel body; 12-Opening; 121-Main grid opening; 122-Overlap opening; 1221-Sub-grid overlap opening; 1222-Pad opening; 123-Branch opening; 1223-Branch overlap opening; 20-Supporting component; 21-First steel wire; 22-Second steel wire; 23-First support component; 24-Second support component; 25-Third support component; 50-Battery cell; 60-Scraper; 70-Slurry. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] In this application, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0029] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0030] A fully open screen is a type of screen used in the production of solar cells. In the electrode production process of solar cells, paste is usually printed onto the solar cell through a screen structure to form electrodes. The characteristic of a fully open screen is that there are no supporting obstructions such as yarns in the open area, so conductive silver paste can directly pass through the open pattern and be deposited on the solar cell.

[0031] Existing electroforming fully open screen printing plates use steel plates for the film layer. Multiple openings are cut into the steel plate according to the shape of the electrodes. The paste is printed onto the solar cell through the openings of the steel plate. Since each opening is an integral open structure, the height and undulation of the main grid and the auxiliary overlapping parts are basically the same during the printing process. However, when welding the solder strips on the main grid, if the paste height of other overlapping parts on the main grid is insufficient, it is easy to cause the solder strips on the main grid to break, which will reduce the efficiency of the solar cell or even make it impossible to manufacture the module.

[0032] In view of this, some embodiments of this application provide a screen structure that allows the overlapping structure on the main grid to be thicker than the paste on the main grid on the cell, ensuring more reliable contact and welding when the solder strip is welded to the main grid, thereby improving the cell yield.

[0033] The present application will be described in detail below through specific embodiments:

[0034] The screen layout structure of this application embodiment is as follows: Figures 1-6 As shown, the screen layout structure includes:

[0035] The screen body 10 includes a first surface close to the battery cell 50 and a second surface away from the battery cell 50. The screen body 10 includes a plate 11 and an opening 12 provided on the plate 11. The opening 12 extends along the thickness direction of the plate 11 and is used for the paste 70 to pass through so that the paste 70 forms an electrode on the battery cell 50. The opening 12 includes a main grid opening 121 and an overlap opening 122. The main grid opening 121 is used to form a main grid, and the overlap opening 122 is connected to the main grid opening 121 and is used to form an overlap structure on the main grid.

[0036] The support member 20 is disposed on the first surface and is provided corresponding to the overlap opening 122. The support member 20 is configured to support part of the slurry 70 when laying the slurry 70 and to allow the slurry to pass through when imprinting the slurry 70.

[0037] The screen printing structure provided in this embodiment includes a screen printing body 10 with a first surface near the battery cell 50 and a second surface away from the battery cell 50. The screen printing body 10 includes a plate 11 and an opening 12 on the plate 11. The opening 12 extends along the thickness direction of the plate 11 and allows slurry 70 to pass through. Therefore, after the slurry 70 passes through the opening 12 and reaches the battery cell 50, it forms electrodes on the battery cell 50. The opening 12 includes a main grid opening 121 and an overlap opening 122. The main grid opening 121 forms a main grid on the battery cell 50, and the overlap opening 122 communicates with the main grid opening 121 and forms an overlap structure on the main grid. Figures 5-6As shown, this application further provides a support member 20 on the first surface of the grid version 10 near the battery cell 50, and the support member 20 is positioned corresponding to the overlap opening 122. The support member 20 is configured to support the slurry 70 during the application of the slurry 70 and allow the slurry 70 to pass through during the imprinting process. Thus, during the application of the slurry 70, because the support member 20 can support the slurry 70, the overlap opening 122 has more slurry 70 that can pass through compared to the position of the main grid opening 121 during the imprinting process. By using a method that makes the overlap structure on the main grid thicker than the paste 70 on the cell 50, sufficient paste is ensured at the overlap structure during actual production. This avoids electrode defects caused by insufficient paste 70. When the solder ribbon passes through the main grid, the overlap structure on the main grid has sufficient height to accommodate the offset of the solder ribbon, ensuring more reliable contact and welding. This solves the welding defects caused by the excessively low grid lines in the fully open screen printing, thereby improving the electrical performance and stability of the cell 50 and increasing the yield of the cell 50.

[0038] Specifically, such as Figure 4 As shown, the support member 20 includes multiple spaced-apart first steel wires 21. The first steel wires 21 cross the overlap opening 122, and both ends of the first steel wires 21 are connected to the plate body 11. The spaced-apart arrangement of the multiple first steel wires 21 can ensure that a certain amount of slurry 70 can pass through during the imprinting process while supporting a portion of the slurry 70. The connection of the two ends of the first steel wires 21 to the plate body 11 provides stable support, ensuring that the support member 20 can withstand greater pressure without deformation or displacement during the imprinting of the slurry 70, thus ensuring the accuracy and repeatability of the process. In the actual slurry 70 laying and imprinting process, the spaced-apart first steel wires 21 can evenly support a portion of the slurry 70, making the overlap structure formed at the overlap opening 122 more uniform and complete. Meanwhile, due to the rigidity of the steel wire and its stable connection with the plate 11, it can withstand the pressure during the imprinting process, ensuring the accurate deposition of the paste 70 and improving the overall quality stability of the product. The spacing between the steel wires allows an appropriate amount of paste 70 to pass through, ensuring the supporting function without excessively blocking the paste 70, which helps to form a complete and continuous overlapping structure.

[0039] Furthermore, the parallel arrangement of multiple first steel wires 21 ensures that each wire experiences a more consistent stress when supporting the slurry 70 and bearing the imprinting pressure. This helps to evenly distribute the force, reduce local stress concentration, and thus improve the overall stability and durability of the support 20. During long-term use, it can prevent some steel wires from being damaged prematurely due to excessive stress, extending the service life of the support 20. The multiple parallel first steel wires 21 can provide more regular spacing, making the slurry 70 more evenly distributed during transmission, further ensuring the consistency of the quality of the overlapping structure. During the flow of the slurry 70, the parallel first steel wires 21 can reduce the turbulence and eddy currents in the slurry 70 caused by irregular wire arrangement, allowing the slurry 70 to pass through and deposit more smoothly. This uniform distribution of the slurry 70 can significantly improve the performance and stability of the electrode.

[0040] Furthermore, to enhance the structural strength and stability of the support component 20, the support component 20 also includes multiple second steel wires 22 perpendicular to the first steel wire 21. The second steel wires 22 are connected to the first steel wire 21 to form a wire mesh. In this way, the first steel wire 21 and the second steel wire 22 are perpendicular to each other to form a wire mesh, which greatly enhances the overall structural strength and stability. When supporting the slurry 70 and bearing the pressure, it can more evenly distribute stress and reduce the risk of local deformation or damage. At the same time, the vertically intersecting wire mesh forms a finer and more uniform mesh structure, which allows the slurry 70 to be distributed more evenly when passing through, thereby forming a more uniform and consistent overlapping structure on the solar cell 50. The wire mesh can better constrain and guide the flow direction of the slurry 70, avoiding disorderly flow or accumulation of the slurry 70 at the overlapping opening 122, and ensuring that the slurry 70 is accurately deposited at the predetermined position. Moreover, the vertically intersecting structure can effectively resist tensile and torsional forces from different directions, ensuring that the support component 20 maintains its shape and function in complex production environments. This regular wire mesh structure is easy to standardize for mass production, and it makes it easier to check indicators such as mesh uniformity and wire connection strength during quality inspection, which helps to ensure the consistency of product quality.

[0041] In this embodiment, the main grid opening 121 extends along the first direction, and the first steel wire 21 extends along the first direction. The extension direction of the first steel wire 21 is consistent with that of the main grid opening 121, which can better adapt to the shape and size of the overlapping opening 122 on the main grid opening 121, providing a more fitting and effective support. This consistent direction helps to disperse the stress generated during the imprinting process of the paste 70, avoiding structural damage or uneven distribution of paste 70 caused by stress concentration at specific locations, thereby improving the efficiency and quality of electrode formation. At the same time, since the main grid opening 121 is relatively long, maintaining the same extension direction can make the entire support structure more uniform and stable in mechanical properties, improving the reliability of the product.

[0042] Specifically, the overlap opening 122 includes a sub-gate overlap opening 1221 and a pad opening 1222. The sub-gate overlap opening 1221 is used to form a connection structure between the main gate and the sub-gate, and the pad opening 1222 is used to form a pad. The support member 20 includes a first support member 23 and a second support member 24. The first support member 23 is disposed corresponding to the sub-gate overlap opening 1221, and the second support member 24 is disposed corresponding to the pad opening 1222. The first support member 23 corresponding to the sub-gate overlap opening 1221 and the second support member 24 corresponding to the pad opening 1222 can accommodate overlaps with different functions and structures. The opening 122 provides targeted support, which helps to precisely control the distribution and deposition of slurry 70 according to the different requirements of the sub-busbar overlap opening 1221 and the pad opening 1222. The connection structure between the main busbar and the sub-busbar requires specific slurry amount and distribution to ensure good electrical connection, while the pad may require different slurry thickness and shape to meet welding requirements. The separate support 20 can better meet the respective process parameters of the sub-busbar overlap and the pad, improve the connection structure between the main busbar and the sub-busbar and the quality and performance of the pad, thereby improving the overall electrical performance of the cell 50. At the same time, the parameters of the first support 23 and the second support 24, such as the number and spacing of steel wires, can be independently adjusted according to different design requirements and production conditions to adapt to diverse production needs. Due to the special support design for key parts, problems such as poor connection and false welding caused by uneven or insufficient slurry 70 are reduced, thereby reducing the defect rate of products. When quality problems occur, it is possible to quickly locate whether the problem is with the first support 23 corresponding to the sub-grid overlap opening 1221 or the second support 24 corresponding to the pad opening 1222, and carry out targeted troubleshooting and maintenance.

[0043] In this embodiment, multiple sub-busbar overlap openings 1221 are included, which are perpendicular to the main busbar opening 121 and are evenly distributed along a first direction. Multiple first support members 23 are also included, each corresponding one-to-one with a different sub-busbar overlap opening 1221. The even distribution of the sub-busbar overlap openings 1221 along the first direction allows the corresponding first support members 23 to evenly distribute the supporting pressure and slurry weight, resulting in more uniform stress and slurry deposition at each sub-busbar overlap, ensuring consistent performance of the solar cell 50. The evenly distributed sub-busbar overlap openings 1221 and corresponding support members 20 ensure more stable and uniform current transmission between the main and sub-busbars, reducing local resistance differences and thus improving the overall electrical performance and output efficiency of the solar cell 50. The one-to-one correspondence design facilitates standardized operations during production, improving production efficiency and accuracy, and reducing production errors caused by positional deviations or unevenness.

[0044] Furthermore, the main grid opening 121 includes multiple sets, each set forming a main grid. Each set of main grid openings 121 corresponds to a pad opening 1222. Multiple second support members 24 are included, each corresponding one-to-one with a pad opening 1222. This ensures precise positioning and support for each pad, guaranteeing the accuracy and stability of pad formation, making the connection between the pad and the main grid more reliable, facilitating uniform current transmission, reducing resistance and energy loss, and improving the power generation efficiency of the solar cell 50. Simultaneously, different main grid designs can flexibly match the corresponding pad openings 1222 and support members 20 to adapt to different application scenarios and performance requirements.

[0045] Furthermore, the overlap opening 122 also includes branch openings 123 located on both sides of the pad opening 1222. The branch openings 123 are parallel to the main gate opening 121 and are used to form branch grid lines at the ends of the main gate. The overlap opening 122 also includes branch overlap openings 1223 perpendicularly disposed on the branch openings 123 and are used to form a connection structure between the branch grid lines and the sub-gate. The support member 20 includes a third support member 25, which is disposed corresponding to the branch overlap opening 1223. The arrangement of the branch openings 123 and the branch overlap openings 1223 enriches the structure of the main gate, enabling more effective current collection and improving the photoelectric conversion efficiency of the solar cell 50. A reasonable branch layout can improve the efficiency and stability of current transmission. By setting a third support 25 corresponding to the branch overlap opening 1223, the stability of the connection structure between the branch grid line and the sub-grid can be ensured, reducing the problem of increased resistance or open circuit caused by poor connection during use. The third support 25 can accurately support and control the slurry 70 at the branch overlap, ensuring that the slurry 70 is evenly distributed at the branch overlap opening 1223, thereby forming a high-quality connection structure. This allows the solar cell 50 to better adapt to different light conditions and current collection requirements, improving the performance of the solar cell 50 in practical applications.

[0046] Meanwhile, multiple branch overlap openings 1223 are included, each perpendicular to the branch opening 1223 and evenly distributed along the first direction. Multiple third support members 25 are also included, with each first support member 23 corresponding one-to-one with a multiple sub-busbar overlap opening 1221. The even distribution of the multiple branch overlap openings 1223 along the first direction allows the corresponding multiple third support members 25 to evenly distribute the support pressure and slurry weight, ensuring uniform stress at each branch overlap and guaranteeing the consistency of the cell 50's performance. The evenly distributed branch overlap openings 1223 and support members 20 facilitate uniform current transmission between the branch busbars and sub-busbars, reducing current collection non-uniformity and thus improving the overall performance and efficiency of the cell 50. The one-to-one correspondence design allows for more precise control of the slurry 70 filling and structural formation at each branch overlap opening 1223 during production, ensuring product consistency and high quality. Since each branch overlap opening 1223 has a corresponding stable support, the number of defective products caused by uneven distribution of slurry 70 or structural defects is reduced, and the product qualification rate is improved.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A screen printing structure for printing electrodes on solar cells, characterized in that, include: A wire mesh body includes a first surface close to the solar cell and a second surface away from the solar cell. The wire mesh body includes a plate and an opening provided on the plate. The opening extends along the thickness direction of the plate and is used for paste to pass through, so that the paste forms electrodes on the solar cell. The opening includes a main grid opening and an overlap opening. The main grid opening is used to form a main grid, and the overlap opening is connected to the main grid opening to form an overlap structure on the main grid. A support member is disposed on the first surface and corresponding to the overlap opening. The support member is configured to support part of the slurry when the slurry is laid and to allow the slurry to pass through when the slurry is imprinted.

2. The screen printing structure according to claim 1, characterized in that, The support member includes multiple spaced-apart first steel wires, which cross the overlapping opening and are connected at both ends to the plate.

3. The screen printing structure according to claim 2, characterized in that, Multiple first steel wires are arranged in parallel.

4. The screen printing structure according to claim 2, characterized in that, The support also includes multiple second steel wires perpendicular to the first steel wire, and the second steel wires are connected to the first steel wire to form a wire mesh.

5. The screen printing structure according to claim 2, characterized in that, The main grid opening extends along a first direction, and the first steel wire extends along the first direction.

6. The screen printing structure according to claim 5, characterized in that, The overlap opening includes a sub-gate overlap opening and a pad opening. The sub-gate overlap opening is used to form a connection structure between the main gate and the sub-gate. The pad opening is used to form a pad. The support member includes a first support member and a second support member. The first support member is provided corresponding to the sub-gate overlap opening, and the second support member is provided corresponding to the pad opening.

7. The screen printing structure according to claim 6, characterized in that, The sub-gate overlap opening includes multiple sub-gate overlap openings, which are perpendicular to the main gate opening and are evenly distributed along the first direction. The first support member includes multiple first support members, which correspond one-to-one with the multiple sub-gate overlap openings.

8. The screen printing structure according to claim 6, characterized in that, The main gate opening includes multiple sets, each set of the main gate opening is used to form a main gate, and each set of the main gate opening corresponds to a pad opening. The second support includes multiple second support members, and the multiple second support members correspond one-to-one with the multiple pad openings.

9. The screen printing structure according to claim 6, characterized in that, The opening also includes branch openings located on both sides of the pad opening. The branch openings are parallel to the main gate opening and are used to form branch gate lines at the end of the main gate. The overlap opening also includes a branch overlap opening perpendicular to the branch opening. The branch overlap opening is used to form a connection structure between the branch gate line and the sub-gate. The support member includes a third support member, which is provided corresponding to the branch overlap opening.

10. The screen printing structure according to claim 9, characterized in that, The branch overlap opening includes multiple branches, which are perpendicular to the branch opening and are evenly distributed along the first direction. The third support includes multiple first supports, which correspond one-to-one with the multiple sub-grid overlap openings.

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