Main grid screen printing plate of photovoltaic cell

Abstract

The utility model discloses a main grid screen printing plate of a photovoltaic cell. The main grid screen printing plate comprises a metal grid layer and a screen cloth layer, the screen cloth layer is provided with a first blanking hole used for printing PAD points, a second blanking hole used for printing main grid lines, and a third blanking hole communicated with the first blanking hole and the second blanking hole. The metal grid layer comprises a plurality of metal wires which are arranged in a crossed mode in the first direction and the second direction which are perpendicular to each other. The plurality of metal wires extending along the first direction in a partial area of the first blanking hole are cut-off metal wires; in the second direction, the cut-off metal wires are arranged from the third blanking hole to the two ends of the first blanking hole; the length of each cut-off metal wire is larger than the width size of the first discharging hole in the first direction. And the width of the third blanking hole is greater than that of the second blanking hole in the second direction. According to the main grid screen printing plate, the virtual printing hollow-out phenomenon of the main grid lines and the PAD points on the photovoltaic cell pieces is effectively avoided, and the reliability of a photovoltaic module is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic cell grid line printing technology, and in particular to a main grid plate for photovoltaic cells. Background Technology

[0002] In the photovoltaic industry, screen printing is mainly used for electrode forming on photovoltaic cells. The front electrode of a photovoltaic cell consists of main grid lines and sub-grid lines. The main grid lines are relatively thicker and are used to directly connect to the circuit outside the cell to transmit the current generated by the photovoltaic cell. The sub-grid lines are relatively thinner and are made into narrow grid lines to overcome the resistance of the diffusion layer.

[0003] A gridless main grid screen is used to print the main grid lines and PAD dots on photovoltaic cells. In the actual printing process of the main grid screen, effectively avoiding incomplete printing and cutouts is crucial to preventing poor soldering of photovoltaic modules and ensuring their reliability. Utility Model Content

[0004] The purpose of this invention is to provide a main grid plate for photovoltaic cells that can largely avoid the problem of false printing and hollowing of main grid lines and PAD points on photovoltaic cells, thereby effectively avoiding the problem of poor soldering of photovoltaic modules and ensuring the reliability of photovoltaic modules.

[0005] To solve the above-mentioned technical problems, this utility model provides a photovoltaic cell main grid plate, characterized in that it includes a metal mesh layer and a mesh fabric layer that are bonded together; the mesh fabric layer is provided with a plurality of first feeding holes, a plurality of second feeding holes, and a plurality of third feeding holes; the first feeding holes and the second feeding holes are connected through the third feeding holes; the first feeding holes are used for printing PAD dots, and the second feeding holes are used for printing main grid lines; the metal mesh layer includes a plurality of metal wires that are respectively arranged intersecting along a first direction and a second direction that are perpendicular to each other; the first direction is the length extension direction of the second feeding holes;

[0006] Among them, a plurality of metal wires extending along the first direction in a portion of the first feeding hole are cut metal wires;

[0007] In the second direction, the plurality of cut metal wires are arranged sequentially from the connection between the first feeding hole and the third feeding hole toward both ends of the first feeding hole;

[0008] In the second direction, the width of the area where each of the cut metal wires is located is smaller than the width of the first feeding hole;

[0009] The length of each of the cut metal wires is greater than the width of the first feeding hole in the first direction;

[0010] In the second direction, the width of the third material discharge hole is greater than the width of the second material discharge hole.

[0011] In an optional embodiment of the present application, the length L of each of the truncated metal wires satisfies D < L < D + 2d; where D is the width dimension of the first material discharge hole in the first direction, and d is the spacing between adjacent metal wires.

[0012] In an optional embodiment of the present application, in the second direction, among several truncated metal wires corresponding to the area where the same first material discharge hole is located, the length of each truncated metal wire gradually increases from the connection between the first material discharge hole and the third material discharge hole to both ends of the first material discharge hole; and the length difference ∆L between adjacent truncated metal wires satisfies ∆L = 2d, where d is the spacing between adjacent metal wires;

[0013] And among several truncated metal wires corresponding to the area where the same first material discharge hole is located, the length L1 of the shortest truncated metal wire satisfies D < L1 < D + 2d; where D is the width dimension of the first material discharge hole in the first direction, and d is the spacing between adjacent metal wires.

[0014] In an optional embodiment of the present application, the number of the truncated metal wires arranged in parallel corresponding to the position of the same first material discharge hole is 5 to 6.

[0015] In an optional embodiment of the present application, the width of the second material discharge hole in the second direction is less than the unit width, and the unit width is the spacing between adjacent metal wires.

[0016] In an optional embodiment of the present application, the width of the third material discharge hole gradually increases from one end of the second material discharge hole to one end of the first material discharge hole.

[0017] In an optional embodiment of the present application, the third material discharge hole is a trapezoidal hole.

[0018] In an optional embodiment of the present application, the length of the third material discharge hole in the first direction is 0.04 mm to 0.06 mm.

[0019] In an optional embodiment of the present application, the width of one end of the third material discharge hole and the second material discharge hole is greater than or equal to the width of the second material discharge hole; the width of the end where the third material discharge hole is connected to the first material discharge hole is 0.01 mm to 0.03 mm.

[0020] In one optional embodiment of this application, the metal mesh layer is a 500-mesh wire mesh with a thickness of 11µm to 15µm and a tension of 9N to 13N;

[0021] The mesh layer is a PI film with a thickness of 4µm to 8µm.

[0022] This utility model provides a photovoltaic cell main grid plate, comprising a metal mesh layer and a mesh fabric layer bonded together; the mesh fabric layer is provided with a plurality of first feeding holes, a plurality of second feeding holes, and a plurality of third feeding holes; the first feeding holes and the second feeding holes are connected through the third feeding holes; the first feeding holes are used for printing PAD dots, and the second feeding holes are used for printing main grid lines; the metal mesh layer includes a plurality of metal wires intersecting along a first direction and a second direction respectively perpendicular to each other; the first direction is the length extension direction of the second feeding holes; wherein, in a portion of the first feeding hole, the plurality of metal wires extending along the first direction are truncated metal wires; in the second direction, the plurality of truncated metal wires are arranged sequentially from the connection point of the first feeding hole and the third feeding hole to both ends of the first feeding hole; in the second direction, the width of the area where each truncated metal wire is located is less than the width of the first feeding hole; the length of each truncated metal wire is greater than the width of the first feeding hole in the first direction; in the second direction, the width of the third feeding hole is greater than the width of the second feeding hole.

[0023] In the main grid stencil of this application, to prevent the metal wires in the metal mesh layer from affecting the paste feeding in the area where the second feeding hole is located, and thus affecting the printing of the main grid lines, the metal wires extending along the second direction in the area corresponding to the second feeding hole are cut off, and only the portion of the metal wire in the first feeding hole is retained. This forms a cut-off metal wire located in a portion of the first feeding hole, while the metal wires along the first direction in the area where the second feeding hole is located are completely retained, thereby ensuring the effective printing of the main grid lines. Furthermore, the length of the cut-off metal wire is greater than the width of the first feeding hole in the first direction, thus allowing the cut-off metal wire to extend from the first feeding hole... The feeding holes extend outwards on both sides in the second direction, which largely avoids the problem of broken metal wires and thus avoids the problem of PAD dots being printed in a false manner due to broken metal wires. Furthermore, the width of the third feeding hole, which connects the second and first feeding holes, is greater than that of the second feeding hole. This avoids the problem of the two ends of the broken metal wires extending to the second feeding hole and causing the paste printing to be obstructed, thus ensuring a reliable connection between the printed main grid lines and PAD dots. This effectively avoids the phenomenon of false printing and hollowing out of the main grid lines and PAD dots on the photovoltaic cells, ensuring the reliability of the photovoltaic modules. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A partial structural schematic diagram of the main grid plate of the photovoltaic cell provided in an embodiment of this application;

[0026] Figure 2 This is another partial structural schematic diagram of the main grid plate of the photovoltaic cell provided in the embodiments of this application;

[0027] In the attached diagram: 10 is the metal mesh layer, 11 is the metal wire, 12 is the cut metal wire, 20 is the mesh fabric layer, 21 is the first feeding hole, 22 is the second feeding hole, and 23 is the third feeding hole. Detailed Implementation

[0028] The core of this application is to provide a main grid pattern for photovoltaic cells, which effectively avoids false printing of main grid lines and PAD points on photovoltaic cells, thereby ensuring the reliability of photovoltaic modules formed by the fabrication of such photovoltaic cells.

[0029] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] like Figure 1 and Figure 2 As shown, Figure 1 A partial structural schematic diagram of the main grid plate of the photovoltaic cell provided in an embodiment of this application; Figure 2 This is another partial structural schematic diagram of the main grid plate of the photovoltaic cell provided in the embodiments of this application.

[0031] In one specific embodiment of this application, the main grid grid includes:

[0032] The metal mesh layer and the mesh fabric layer 20 are bonded together;

[0033] The mesh layer 20 is provided with a plurality of first feeding holes 21, a plurality of second feeding holes 22 and a plurality of third feeding holes 23; the first feeding holes 21 and the second feeding holes 22 are connected through the third feeding holes 23; the first feeding holes 21 are used for printing PAD dots, and the second feeding holes 22 are used for printing main grid lines; the metal mesh layer includes a plurality of metal wires 11 arranged intersecting along a first direction and a second direction that are perpendicular to each other; the first direction is the length extension direction of the second feeding holes 21.

[0034] Among them, a plurality of metal wires 11 extending along the first direction in a portion of the first feeding hole 21 are cut metal wires 12.

[0035] In the second direction, a number of cut metal wires 12 are arranged sequentially from the connection between the first feed hole 21 and the third feed hole 23 toward both ends of the first feed hole 21.

[0036] In the second direction, the width of the area where each cut metal wire 12 is located is smaller than the width of the first feeding hole 21;

[0037] The length of each cut metal wire 12 is greater than the width of the first feeding hole 21 in the first direction;

[0038] In the second direction, the width of the third discharge hole 23 is greater than the width of the second discharge hole 22.

[0039] It is understandable that the main grid plate mainly consists of a metal mesh layer and a mesh layer 20 that are bonded together; the mesh layer 20 can be a PI film with a thickness of 4um to 8um.

[0040] A first feeding hole 21 and a second feeding hole 22 are provided on the mesh layer 20. The first feeding hole 21 is used to feed the PAD points printed on the photovoltaic cell and is roughly square. The second feeding hole 22 is used to feed the main grid lines printed on the photovoltaic cell and is roughly straight. The shape and position of the first feeding hole 21 and the second feeding hole 22 on the mesh layer 20 correspond to the shape and position of the PAD points and the main grid lines on the photovoltaic cell. The relative position between the first feeding hole 21 and the second feeding hole 22 can be referenced to the relative position between the PAD points and the main grid lines on the photovoltaic cell.

[0041] In the actual printing process, the paste is placed on the main grid and squeezed by a scraper. The opposing force between the metal grid layer and the scraper causes the paste to leak from the first feed hole 21 and the second feed hole 22 onto the surface of the photovoltaic cell, thereby realizing the printing of PAD points and main grid lines on the surface of the photovoltaic cell.

[0042] In this embodiment, the metal mesh layer is composed of metal wires 11 arranged longitudinally and transversely along a first direction and a second direction that are perpendicular to each other. The first direction is also the length extension direction of the second feed hole 22. That is to say, the metal mesh layer in this application is a mesh structure formed by the interlacing of metal wires 11 along squares parallel and perpendicular to the length of the second feed hole 22. In practical applications, the metal mesh layer can be a 500-mesh wire mesh with a thickness of 11µm to 15µm and a tension of 9N to 13N.

[0043] Based on this, since the metal wire 11 extending along the first direction and the second feeding hole 22 are parallel to each other, if there is a metal wire 11 parallel to the second feeding hole 22, this metal wire 11 will affect the ink leakage printing at the second feeding hole 22 to a certain extent, thus leading to poor printing effect of the main grid line. Therefore, in this embodiment, the metal wire 11 in the strip area corresponding to the second feeding hole 22 on the metal grid layer is cut off, and only the part corresponding to the area where the first feeding hole 21 is located is retained, that is, the cut metal wire 12 located in the area corresponding to the first feeding hole 21 is formed; for each cut metal wire 12 in the same area of ​​the first feeding hole 21, they are arranged approximately symmetrically to both sides of the straight line where the second feeding hole 22 is connected to the first feeding hole 21.

[0044] The cut metal wire 12 is formed by using a laser to cut multiple complete metal wires 11 extending along the first direction. The cut metal wires are the area where the second feed hole 22 is located and the multiple metal wires on both sides adjacent to the second feed hole 22. Only the section of the cut metal wire 12 located in the area where the first feed hole 21 is located is retained, thus forming the cut metal wire 12. This ensures that the paste can flow out smoothly from the second feed hole 22 for printing during the actual printing process.

[0045] Furthermore, in this embodiment, in the second direction, the width of the area where each cut metal wire 12 is located is smaller than the width of the first feeding hole 21, approximately 5 to 6 times the unit width d. The unit width d is equal to the distance between two adjacent parallel metal wires 11. Therefore, the number of cut metal wires 12 corresponding to the area where the same first feeding hole 21 is located can be 5 to 6. This effectively avoids the possibility of metal wires extending in the first direction obstructing the printing of paste at the second feeding hole 22, thus ensuring the printing effect of forming the main grid lines.

[0046] It should be noted that in this embodiment, the reason why only the metal wires 11 extending along the first direction in the section where the second feeding hole 22 is located and the areas adjacent to and on both sides of the second feeding hole 22 are cut off and removed, while retaining a portion of the cut metal wires 12 in the area where the first feeding hole 21 is located, is because the opening area of ​​the first feeding hole 21 is larger than that of the second feeding hole 22. If part of the metal wires 11 along the first direction is removed, the mutual extrusion force between that portion of the metal wires 11 and the doctor blade in the first feeding hole 21 will be insufficient, resulting in insufficient ink leakage during printing, thus causing the problem of false printing of PAD dots. Therefore, in this embodiment, a portion of the metal wires 11, that is, the cut metal wires 12, is retained in the area within the designated strip area 30 corresponding to the position of the first feeding hole 21.

[0047] In addition, such as Figure 1 and Figure 2 As described above, in this embodiment, the two ends of the cut metal wire 12 should each overlap a metal wire 11 extending in the second direction. The end of the cut metal wire 12 is also a relatively unstable position on the cut metal wire 12. Once this part falls off, it may cause the entire cut metal wire 12 to fall off and break, which will lead to the problem of false printing of PAD points and shorten the service life of the main grid plate. Therefore, in this embodiment, the length of the cut metal wire 12 is greater than the width of the first feeding hole 21 in the first direction. This means that both ends of the cut metal wire 12 extend out from both sides of the first feeding hole 21 in the first direction, so that the ends of the cut metal wire 12 are located outside the area of ​​the first feeding hole 21 where a large amount of printing paste needs to be discharged. Thus, in the actual printing process, due to the bearing effect of the mesh layer 20 in the area where the ends of the cut metal wire 12 are located, the impact and squeezing force on the ends of the cut metal wire 12 can be reduced to a certain extent, thereby reducing the possibility of the cut metal wire 12 falling off and breaking, improving the service life of the cut metal wire 12, and effectively ensuring the printing effect of the PAD dots.

[0048] Based on this, since the ends of the cut metal wire 12 extend from both sides of the first feeding hole 21 in the first direction, it is possible that the ends of the cut metal wire 12 may extend into the second feeding hole 22, thereby hindering the printing of the section where the main grid line and PAD point are connected, and even causing the main grid line and PAD point to be disconnected from each other. To this end, in this embodiment, the width of the third feeding hole 23, which connects the strip printing hole and the square printing hole, is set to be greater than the width of the strip printing hole, so that there can be enough paste to flow down and print in the third feeding hole 23, thereby ensuring that there is enough paste for printing connection between the main grid line and PAD point printed on the photovoltaic cell, that is, ensuring the printing connection effect of the main grid line and PAD point.

[0049] It can be understood that the length L of the truncated wire 12 in this embodiment can be only slightly greater than the width D of the first blanking hole 21 in the first direction, satisfying D < L < D + 2d; where D is the width dimension of the first blanking hole 21 in the first direction, and d is the spacing between adjacent wires.

[0050] As Figure 1 shown, in Figure 1 the embodiment shown, the length L of each truncated wire 12 can be less than the sum of the width D of the first blanking hole 21 in the first square and twice the unit width d on the basis of being greater than the width D of the first blanking hole 21 in the first direction. This avoids the end of the truncated wire 12 extending too long into the area where the second blanking hole 22 is located.

[0051] Of course, in practical applications, the straight line where the second blanking hole 22 is located should also be approximately the central symmetry line of the first blanking hole 21. To further ensure the structural stability of the truncated wire 12, as Figure 2 shown, in another optional embodiment of the present application, the truncated wire 12 can further include:

[0052] In the second direction, among several truncated wires 12 corresponding to the area where the same first blanking hole 21 is located, the length of each truncated wire 12 gradually increases from the connection of the first blanking hole 21 and the third blanking hole 23 to both ends of the first blanking hole 21; and the length difference ∆L between adjacent two truncated wires 12 satisfies ∆L = 2d, where d is the unit width, that is, the spacing between adjacent two wires 11;

[0053] And among several truncated wires 12 corresponding to the area where the same first blanking hole 21 is located, the length L1 of the shortest truncated wire satisfies D < L1 < D + 2d, where D is the width D of the first blanking hole 21 in the first direction, and d is the unit width, that is, the spacing between adjacent two wires 11.

[0054] Different from the above Figure 1 shown embodiment, in Figure 2 the embodiment shown, the lengths of the truncated wires 12 corresponding to the same position of the first blanking hole 21 are not uniform, but increase gradually from the straight line where the second blanking hole 22 is located to both sides of this straight line. That is, the shorter the length of the truncated wire 12 closer to the straight line where the second blanking hole 22 is located, and vice versa, the longer the length of the truncated wire 12 farther from the straight line where the second blanking hole 22 is located. And the length difference between adjacent two truncated wires 12 is equal to twice the unit width, so that the two ends of each truncated wire 12 differ by a length of one unit width d compared with the two ends of the adjacent truncated wire 12.

[0055] As Figure 2 As shown, in Figure 2 In the illustrated embodiment, five parallel cut metal wires 12 are arranged on the same first feeding hole 21, with the middle cut metal wire 12 being the shortest, and the length of each cut metal wire 12 increasing sequentially towards both sides in the second direction. In practical applications, the number of cut metal wires 12 corresponding to the area of ​​the same first feeding hole 21 is even, such as six. In this case, the two middle cut metal wires 12 can be the shortest and equal in length, and the length of each cut metal wire 12 towards both sides in the second direction can then increase sequentially, thus achieving the technical solution of this application.

[0056] It is understandable that the second feeding hole 22 in this application generally corresponds to the area where the shortest cut metal wire is located. Even if there is a slight deviation, it is located in... Figure 2 The outermost multiple cut metal wires 12 shown are relatively long and generally do not extend into the area inside the second feed hole 22, that is, they do not affect the printing of the main grid lines.

[0057] Based on this, the width of the second feeding hole 22 in the second direction is less than the unit width, that is, less than the spacing between two adjacent metal wires 11; to avoid the printed main grid line being too narrow, which would affect the main grid line's ability to block light from the surface of the photovoltaic cell.

[0058] Based on the above discussion, in another optional embodiment of this application, the width of the third feeding hole 23, which connects the second feeding hole 22 and the first feeding hole 21, gradually increases from one end of the second feeding hole 22 to one end of the first feeding hole 21. This results in a gradual change in the connection structure between the printed main grid lines and the PAD points, improving the printing connection effect.

[0059] In practical applications, the third feeding hole 23 can be a trapezoidal hole, and the connection structure formed by printing the connection between the main grid line and the PAD point is also a trapezoidal connection structure. Of course, in practical applications, the two sides of the transition section are not necessarily straight sides; they can also be stepped sides or curved sides. This application does not impose specific restrictions on this.

[0060] Furthermore, the length of the third feeding hole 23 in the first direction can be 0.04mm to 0.06mm; for example, it can be 0.04mm, 0.05mm, or 0.06mm.

[0061] Furthermore, such as Figure 1 and Figure 2 As shown, the width of one end of the third discharge hole 23 and the second discharge hole 22 is greater than or equal to the width of the second discharge hole 22; the width of the end where the third discharge hole 23 connects to the first discharge hole 21 is 0.01mm~0.03mm.

[0062] In summary, in the main grid screen of this application, to prevent the metal wires in the metal mesh layer from affecting the paste feeding in the area where the second feeding hole is located, and thus affecting the printing of the main grid lines, metal wires parallel to the length extension direction of the second feeding hole are cut off within the designated strip area where the second feeding hole is located, forming cut-off metal wires. This ensures that the cut-off metal wires are only provided in the area above the first feeding hole within the designated strip area, while the area where the second feeding hole is located does not include metal wires along the first direction, thereby ensuring effective printing of the main grid lines. Furthermore, the length of the cut-off metal wires is greater than the width of the first feeding hole in the first direction, thus... This design allows the cut metal wire to extend outwards from both sides of the first feeding hole, significantly reducing the risk of wire breakage and thus preventing the PAD dots from being printed in a false or incomplete manner. Furthermore, the width of the third feeding hole, which connects the first and second feeding holes, is greater than that of the second feeding hole. This prevents the cut metal wire from extending to the second feeding hole and obstructing the printing process, ensuring reliable connectivity between the printed main grid lines and PAD dots. This effectively prevents the false or incomplete printing of the main grid lines and PAD dots on the photovoltaic cell, guaranteeing the reliability of the photovoltaic module.

[0063] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that the elements inherent in a process, method, article, or apparatus that includes a list of elements are included. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. Additionally, portions of the technical solutions provided in the embodiments of this application that are consistent with the implementation principles of corresponding technical solutions in the prior art have not been described in detail to avoid excessive elaboration.

[0064] This article uses specific examples to illustrate the principles and implementation methods of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principles of this utility model, and these improvements and modifications also fall within the protection scope of this utility model.

Claims

1. A photovoltaic cell grid, characterized in that, It includes a metal grid layer and a mesh layer that are mutually adhered and connected; several first material discharge holes, several second material discharge holes, and several third material discharge holes are provided on the mesh layer; the first material discharge holes and the second material discharge holes are connected through the third material discharge holes; the first material discharge holes are used for printing PAD points, and the second material discharge holes are used for printing main grid lines; the metal grid layer includes multiple metal wires that are respectively arranged in a crosswise manner along a first direction and a second direction that are perpendicular to each other; the first direction is the length extension direction of the second material discharge holes; Among them, several of the metal wires that extend along the first direction in a partial area of the first material discharge holes are truncated metal wires; In the second direction, the several truncated metal wires are sequentially arranged from the connection of the first material discharge holes and the third material discharge holes towards both ends of the first material discharge holes; In the second direction, the width of the area where each truncated metal wire is located is smaller than the width of the first material discharge hole; The length of each truncated metal wire is greater than the width of the first material discharge hole in the first direction; In the second direction, the width of the third material discharge hole is greater than the width of the second material discharge hole.

2. The photovoltaic cell grid as described in claim 1, characterized in that, The length L of each truncated metal wire satisfies D < L < D + 2d; where D is the width dimension of the first material discharge hole in the first direction, and d is the spacing between adjacent two metal wires.

3. The photovoltaic cell grid as described in claim 1, characterized in that, In the second direction, among the several truncated metal wires corresponding to the area where the same first material discharge hole is located, the length of each truncated metal wire gradually increases from the connection of the first material discharge hole and the third material discharge hole towards both ends of the first material discharge hole; and the length difference ∆L between adjacent two truncated metal wires satisfies ∆L = 2d, where d is the spacing between adjacent two metal wires; And among the several truncated metal wires corresponding to the area where the same first material discharge hole is located, the length L1 of the shortest truncated metal wire satisfies D < L1 < D + 2d; where D is the width dimension of the first material discharge hole in the first direction, and d is the spacing between adjacent two metal wires.

4. The photovoltaic cell grid as described in claim 1, characterized in that, The number of the truncated metal wires that are arranged in parallel corresponding to the position of the same first material discharge hole is 5 to 6.

5. The main grid plate of the photovoltaic cell as described in any one of claims 1 to 4, characterized in that, The width of the second material discharge hole in the second direction is smaller than the unit width, and the unit width is the spacing between adjacent two metal wires.

6. The photovoltaic cell grid as described in claim 5, characterized in that, The width of the third material discharge hole gradually increases from one end of the second material discharge hole to one end of the first material discharge hole.

7. The photovoltaic cell grid as described in claim 6, characterized in that, The third material discharge hole is a trapezoidal hole.

8. The photovoltaic cell grid as described in claim 6, characterized in that, The length of the third material discharge hole in the first direction is 0.04 mm to 0.06 mm.

9. The photovoltaic cell grid as described in claim 6, characterized in that, The width of one end of the third material discharge hole and the second material discharge hole is greater than or equal to the width of the second material discharge hole; the width of the end where the third material discharge hole is connected to the first material discharge hole is 0.01 mm to 0.03 mm.

10. The photovoltaic cell grid as described in claim 5, characterized in that, The metal grid layer is a 500 - mesh wire mesh, with a thickness of 11 um to ​

Images