Full-opening steel plate with buffer metal layer for battery printing

Abstract

The utility model discloses a full-opening steel plate with a buffer metal layer for battery printing, and belongs to the technical field of solar battery printing. The full-opening steel plate with the buffer metal layer for battery printing comprises a frame, an annular auxiliary material piece and a graphical steel plate, the graphical steel plate is arranged on the annular auxiliary material piece, an avoiding area is larger than a graphic area of the graphical steel plate, the graphical steel plate comprises the buffer metal layer and a first metal layer, the graphic area of the buffer metal layer is provided with a plurality of first grid line holes, and the first grid line holes are communicated with the annular auxiliary material piece. A plurality of second grid line holes are formed in the pattern area of the first metal layer, at least one buffer metal layer is arranged on the pasting and printing face of the first metal layer, the first grid line holes are communicated with the corresponding second grid line holes, and the hardness of the buffer metal layer is smaller than that of the silicon wafer. According to the utility model, the surface of the steel plate can be matched with the uneven surface of the silicon wafer in the printing process, so that the consumption of printing silver paste is saved, the stable batch production is facilitated, and the electrical performance of the battery piece is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to solar cell printing technical field especially relates to a full opening steel plate with buffer metal layer for battery printing. BACKGROUND

[0002] As a key tool for printing solar cell electrodes, screen printing screens play a crucial role in the development process of the photovoltaic industry. With the continuous progress of photovoltaic technology and the increasing demand for photovoltaic module performance, screen printing enterprises have actively responded to market demand and have successively launched knotless screens. This new type of screen has achieved remarkable results in achieving fine line width printing, to some extent, meeting the needs of photovoltaic module production for electrode line width. However, the photovoltaic industry is always in rapid development and change. On the one hand, the photovoltaic module market has put forward new and more stringent requirements for the precision and performance of electrodes. Consumers and the industry have higher expectations for the conversion efficiency, stability, and service life of photovoltaic modules, which requires finer line width and higher line grid flatness of electrodes to reduce resistance and improve current collection efficiency, thereby improving the overall performance of photovoltaic modules. On the other hand, battery technology is also constantly innovating. From traditional battery technology to the emergence of new high-efficiency battery technologies, such as heterojunction cells, perovskite cells, and others, these new technologies have posed new challenges to the precision, stability, and adaptability of printing screens. The existing silk screen screens gradually reveal their limitations when faced with these increasing requirements, and have difficulty meeting the strict requirements of extremely fine line width and line grid flatness.

[0003] Under this background, full opening steel screens have emerged. Full opening steel screens, with their unique manufacturing process and material properties, have shown excellent performance in achieving extremely fine line width printing. It can accurately control the line width of the electrode to reach micrometer level, greatly improving the precision of the electrode. At the same time, full opening steel screens can also effectively ensure the flatness of the line grid, reducing the increase in resistance and current loss caused by uneven line grid, thereby meeting the requirements of extremely fine line width while also meeting the requirements of line grid flatness, providing strong support for the improvement of photovoltaic module performance.

[0004] However, taking the Back Contact cell (hereinafter referred to as BC cell) as an example, its surface has a unique process structure. In order to realize the structure design of back contact, the layout and form of the surface electrode of the BC cell are quite different from those of the traditional cell. This unique process makes it impossible for the full opening steel plate to perfectly fit when it comes into contact with the surface of the cell. During the printing process, due to the mismatch between the steel plate and the surface of the cell, the printed electrode appears thick lines, uneven lines and other phenomena. Thick electrode lines will increase the resistance and reduce the current collection efficiency; uneven lines will affect the stability of the connection between the electrodes, thereby negatively affecting the conversion efficiency of the cell. At the same time, these printing problems will also increase the rate of defective products in the production process, reduce production efficiency, and increase production cost. In the printing process of Topcon cell, the full opening steel plate also exposes similar problems. Topcon cell is a new type of high-efficiency cell technology, which has very high requirements for the precision and uniformity of the electrode. However, when the full opening steel plate is used to print Topcon front cell and back poly finger (similar in appearance to BC), it also appears thick lines and irregular line expansion. These printing defects not only affect the appearance quality of the cell, but more importantly, they reduce the conversion efficiency of the cell, making the cell unable to fully exert its performance in actual application. Moreover, irregular line expansion may also cause short circuit and other safety hazards in the subsequent packaging and use of the cell,

[0005] This part provides background information related to the present application, which may not be prior art. Practical new content

[0006] The purpose of the present application is to provide a full opening steel plate with a buffer metal layer for cell printing, which can fit the uneven surface of the silicon wafer during the printing process. This not only saves the consumption of printed silver paste, but also helps stable mass production and improves the electrical performance of the cell.

[0007] To achieve the above purpose, the following technical solutions are provided:

[0008] The full opening steel plate with a buffer metal layer for cell printing comprises:

[0009] The frame comprises a fixed edge, and the fixed edge is circumferentially surrounded to form a mounting area;

[0010] The annular auxiliary material piece is located in the mounting area, the outer edge of the annular auxiliary material piece is connected with the fixed edge, and the inner edge of the annular auxiliary material piece is circumferentially surrounded to form a clearance area;

[0011] The graphic steel plate is arranged on the annular auxiliary material piece, the avoiding area is larger than the graphic area of the graphic steel plate, the graphic steel plate comprises a buffer metal layer and a first metal layer, the graphic area of the buffer metal layer has a plurality of first grid line holes, the graphic area of the first metal layer has a plurality of second grid line holes, the printing surface of the first metal layer is provided with at least one buffer metal layer, the first grid line hole is communicated with the corresponding second grid line hole, and the hardness of the buffer metal layer is smaller than the hardness of the silicon wafer.

[0012] As an optional solution of the full-opening steel plate with a buffer metal layer for battery printing, the graphic steel plate further comprises:

[0013] A second metal layer, the graphic area of the second metal layer has a plurality of third grid line holes, the second metal layer is arranged on the squeegee surface of the first metal layer, and the third grid line hole is sequentially communicated with the corresponding second grid line hole and the first grid line hole.

[0014] As an optional solution of the full-opening steel plate with a buffer metal layer for battery printing, the opening line width of the first grid line hole is the same as that of the second grid line hole, and the opening line width of the third grid line hole is greater than that of the second grid line hole.

[0015] As an optional solution of the full-opening steel plate with a buffer metal layer for battery printing, the material of the buffer metal layer is metal tin, tin alloy or metal aluminum.

[0016] As an optional solution of the full-opening steel plate with a buffer metal layer for battery printing, the material of the first metal layer is nickel or nickel alloy.

[0017] As an optional solution of the full-opening steel plate with a buffer metal layer for battery printing, the thickness of the buffer metal layer is not greater than the thickness of the first metal layer.

[0018] As an optional solution of the full-opening steel plate with a buffer metal layer for battery printing, the thickness of the buffer metal layer is 1-6 μm; and / or

[0019] The thickness of the first metal layer is 5-15 μm.

[0020] As an optional solution of the full-opening steel plate with a buffer metal layer for battery printing, the material of the second metal layer is nickel or nickel alloy; and / or

[0021] The thickness of the second metal layer is 5-20 μm.

[0022] As an optional solution of the full-opening steel plate with a buffer metal layer for battery printing, the material of the annular auxiliary material piece is nylon net.

[0023] As the optional scheme of the full opening steel plate with buffer metal layer for battery printing, the frame further comprises a plurality of positioning holes which are arranged on the fixed edge in a circumferential direction.

[0024] Compared with the prior art, the utility model has the beneficial effects of:

[0025] The full opening steel plate with buffer metal layer for battery printing has one or more buffer metal layers with lower hardness than the silicon wafer on the surface of the patterned steel plate, so that the surface of the patterned steel plate can be combined with the uneven surface of the silicon wafer in the printing process, the silver paste is deposited on the battery silicon wafer after passing through the second grid line hole and the first grid line hole in turn, the overflow of the silver paste from the gap between the steel plate and the uneven surface of the silicon wafer is avoided, the grid line shape of the silicon wafer printing is ensured to be uniform and regular, the consumption of the printed silver paste is saved, the stable batch production is achieved, the photoelectric conversion efficiency of the battery silicon wafer is improved, and the electrical performance of the battery wafer is improved. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the utility model, the drawings needed to be used in the description of the embodiments of the utility model will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained according to the contents of the embodiments of the utility model and the drawings without creative labor.

[0027] Figure 1 It is a schematic view of the assembly of the full opening steel plate with buffer metal layer for battery printing in the embodiments of the utility model.

[0028] Figure 2 It is a top view of the frame in the embodiments of the utility model.

[0029] Figure 3 It is a top view of the annular auxiliary material piece in the embodiments of the utility model.

[0030] Figure 4 It is a top view of the patterned steel plate in the embodiments of the utility model.

[0031] Figure 5 It is a sectional view of the patterned steel plate around the grid line hole in the embodiments of the utility model.

[0032] Figure 6 It is a schematic view of the first printing mode of the Back Contact battery wafer (without buffer metal layer) in the embodiments of the utility model.

[0033] Figure 7 It is a schematic view of the second printing mode of the Back Contact battery wafer (with buffer metal layer) in the embodiments of the utility model.

[0034] Figure 8 A schematic view of the first printing method for the Topcon battery piece in the embodiment of the present application (without a buffer metal layer) is shown in the figure.

[0035] Figure 9 A schematic view of the second printing method for the Topcon battery piece in the embodiment of the present application (with a buffer metal layer) is shown in the figure.

[0036] Reference signs:

[0037] 100, doctor blade; 200, silver paste; 300, Back Contact battery piece; 400, Topcon battery piece;

[0038] 1, frame; 2, annular auxiliary material piece; 3, patterned steel plate;

[0039] 11, fixed edge; 12, mounting area; 13, positioning hole;

[0040] 21, avoiding area;

[0041] 31, buffer metal layer; 311, first grid line hole; 32, first metal layer; 321, second grid line hole; 33, second metal layer; 331, third grid line hole. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0043] In the description of the present application, it should be noted that the orientations or position relationships indicated by the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like are based on the orientations or position relationships shown in the drawings, or the orientations or position relationships of the product of the present application when it is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" and the like are only used for differentiation in description, and cannot be understood as indicating or implying relative importance. In the description of the present application, unless otherwise specified, the meaning of "multiple" is two or more.

[0044] In the description of the utility model, still need to explain, unless another explicit provision and limitation, term "arrangement", "connection" should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or integrally connected, can be mechanical connection, also can be electrical connection. For ordinary skilled in the art, can understand the specific meaning of the above terms in the utility model according to specific circumstances.

[0045] The embodiments of the utility model are described in detail below, and the examples of the embodiments are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary, only for explaining the utility model, and cannot be understood as limiting the utility model.

[0046] In order to save the consumption of printing silver paste, help stable batch production, and improve the electrical performance of the battery sheet, the embodiment provides a full-opening steel plate with a buffer metal layer for battery printing. Figures 1 to 9 The specific content of the embodiment is described in detail. It should be noted that the graphic area mentioned in the embodiment refers to the area occupied by the processing of a plurality of grid line holes.

[0047] In the field of battery printing, especially in the printing link of solar cells, the quality and performance of the printing screen play a crucial role in the final electrical performance and production efficiency of the battery sheet. The full-opening steel plate with a buffer metal layer for battery printing provided by the embodiment is an innovative product designed with great care for the pain points existing in the current battery printing process. Its unique structure brings a new solution to improving the quality of battery printing.

[0048] The full-opening steel plate with a buffer metal layer for battery printing mainly consists of a frame 1, a ring-shaped auxiliary material part 2 and a graphic steel plate 3. The frame 1 serves as the supporting structure of the entire steel plate. The frame 1 includes fixed edges 11, which form an installation area 12 around the circumference, providing a stable platform for the installation of the ring-shaped auxiliary material part 2 and the graphic steel plate 3. This frame 1 structure not only ensures the overall strength and stability of the steel plate, but also lays a foundation for the precise installation of subsequent components.

[0049] The ring-shaped auxiliary material part 2 is located in the installation area 12 formed by the frame 1, and its outer edge is closely connected with the fixed edge 11, ensuring the stability of the ring-shaped auxiliary material part 2 in the frame 1. The inner edge of the ring-shaped auxiliary material part 2 forms a clearance area 21 around the circumference, which is larger than the graphic area of the graphic steel plate 3, so that the silver paste 200 can flow smoothly through the clearance area 21 of the ring-shaped auxiliary material part 2 and the graphic steel plate 3.

[0050] The graphic steel plate 3 is the core component of the full-opening steel plate with buffer metal layer for battery printing, which is arranged on the annular auxiliary material piece 2. The graphic steel plate 3 includes a buffer metal layer 31 and a first metal layer 32. The graphic area of the buffer metal layer 31 is distributed with a plurality of first grid line holes 311, and the shape, size and pitch of the first grid line holes 311 are accurately calculated and designed to meet the requirements of grid line linearity and accuracy for battery printing. The graphic area of the first metal layer 32 also has a plurality of second grid line holes 321, and the printing surface of the first metal layer 32 is provided with at least one buffer metal layer 31, and the first grid line hole 311 is in communication with the corresponding second grid line hole 321. This communication design enables the silver paste 200 to smoothly pass through the two layers of grid line holes during the printing process and finally deposit on the battery silicon wafer. It is particularly worth mentioning that the hardness of the buffer metal layer 31 is less than the hardness of the silicon wafer. This feature is one of the key innovations of the full-opening steel plate with buffer metal layer for battery printing. In the actual battery printing process, the surface of the silicon wafer often has a certain unevenness, which is determined by the manufacturing process and material properties of the silicon wafer. If a traditional rigid steel plate is used for printing, there will be a gap between the steel plate and the uneven surface of the silicon wafer, which will cause the silver paste 200 to overflow from the gap during the printing process, thereby affecting the linearity and regularity of the grid lines. However, the buffer metal layer 31 in this embodiment can deform to a certain extent during the printing process due to its hardness being less than that of the silicon wafer, so that the surface of the graphic steel plate 3 can perfectly fit the uneven surface of the silicon wafer.

[0051] The technical effects brought by this fit are multifaceted. First, it can effectively prevent the silver paste 200 from overflowing from the gap between the steel plate and the uneven surface of the silicon wafer. Precise deposition of the silver paste 200 ensures uniform and regular linearity of the grid lines, avoiding problems such as uneven thickness and broken lines of the grid lines caused by silver paste 200 overflow. Uniform and regular grid lines can better collect and conduct current, reducing resistance loss and thus improving the photoelectric conversion efficiency of the battery silicon wafer. Second, due to the improvement of grid line printing quality, the rate of defective products caused by printing defects is reduced, achieving stable batch production. This not only reduces production costs, but also improves production efficiency. In addition, stable printing quality also helps to improve the overall electrical performance of the battery wafer, such as open-circuit voltage, short-circuit current and fill factor. The full-opening steel plate with buffer metal layer for battery printing provided in this embodiment effectively solves the printing quality problems caused by the uneven surface of the silicon wafer in the battery printing process through its unique structural design and the application of the buffer metal layer 31, providing strong technical support for large-scale and efficient production of solar cells.

[0052] Further, the graphic steel plate 3 also comprises a second metal layer 33, the graphic area of the second metal layer 33 has a plurality of third grid line holes 331, the second metal layer 33 is arranged on the squeegee surface of the first metal layer 32, the third grid line holes 331 are sequentially communicated with the corresponding second grid line holes 321 and the first grid line holes 311, forming a complete and unobstructed silver paste 200 channel. The primary and significant technical effect of adding the second metal layer 33 is to greatly improve the overall structural strength of the graphic steel plate 3. In the process of battery printing, the graphic steel plate 3 needs to bear the pressure from the squeegee 100 and the repeated friction effect. The traditional single-layer metal layer structure is prone to bending deformation due to stress concentration under long-term high-strength printing operation. Once the graphic steel plate 3 bends, not only will it affect the printing accuracy, causing problems such as grid line position deviation and line distortion, but also will accelerate the wear of the steel plate, shorten its service life, and increase the production cost of the enterprise. The addition of the second metal layer 33 is equivalent to adding a layer of strong support structure to the graphic steel plate 3. The three-layer metal layer cooperates with each other to bear the external pressure and stress, so that the graphic steel plate 3 can maintain better flatness and stability during printing. Even after a long time of continuous printing, bending deformation can be effectively avoided, ensuring the stability and consistency of the printing quality. From the perspective of printing quality, the graphic steel plate 3 with improved structural strength can better guarantee the printing accuracy of the grid lines. Since the graphic steel plate 3 is no longer prone to bending, the squeegee 100 can apply pressure more uniformly during printing, so that the silver paste 200 can be accurately deposited on the designated position of the battery silicon wafer through the third grid line holes 331, the second grid line holes 321 and the first grid line holes 311. In this way, the printed grid lines are more uniform and regular in shape, and the width and spacing can strictly meet the design requirements. Uniform and regular grid lines can significantly improve the light absorption and current collection efficiency of the battery silicon wafer, reduce resistance loss, and thus directly improve the photoelectric conversion efficiency of the battery silicon wafer. In the traditional printing process, printing defects caused by bending of the steel plate will increase the rate of defective products, and the enterprise needs to spend a lot of time and manpower to rework or reprint, which not only reduces the production efficiency, but also increases the production cost. The graphic steel plate 3 with the added second metal layer 33 in the embodiment can maintain stable printing quality, greatly reducing the generation of defective products and realizing stable batch production.

[0053] Further, the first gate line hole 311 has the same opening line width as the second gate line hole 321, and the third gate line hole 331 has an opening line width greater than that of the second gate line hole 321. The graphic steel plate 3 comprises a three-layer structure, namely a buffer metal layer 31, a first metal layer 32, and a second metal layer 33, and each layer is respectively provided with a first gate line hole 311, a second gate line hole 321, and a third gate line hole 331. Among them, the line width of the first gate line hole 311 is highly consistent with the customer's required line width. This is because in the process of battery printing, customers have clear and strict requirements for the line width of the gate line to meet the electrical performance indicators and design specifications of the battery. For example, in solar cells that pursue high photoelectric conversion efficiency, finer gate line width can reduce the occlusion of light by the gate line and improve the light absorption rate of the battery. Therefore, accurately setting the line width of the first gate line hole 311 to the required line width of the customer is a key step to ensure that the printed gate line meets the performance requirements of the battery. The line width of the second gate line hole 321 is set with reference to the first gate line hole 311, and the opening line widths of the two are the same. This design is not arbitrary, but based on the comprehensive consideration of printing process and material properties. In the printing process, silver paste 200 needs to be deposited on the battery silicon wafer through the first gate line hole 311 and the second gate line hole 321 in turn. If the line widths of the first gate line hole 311 and the second gate line hole 321 are not consistent, it may cause problems such as poor flow and uneven distribution of silver paste 200 when passing through the two layers of gate line holes, thereby affecting the printing quality of the gate line. Keeping the line widths the same can ensure that silver paste 200 has a stable flow state when passing through the two layers of gate line holes, so that silver paste 200 can be uniformly deposited on the silicon wafer to form a linear regular and consistent width gate line. The opening line width of the third gate line hole 331 is greater than that of the second gate line hole 321, and can be externally expanded by 10-200pm on a single side. This design has a dual important role. On the one hand, it provides storage space for printing. In the process of battery printing, the supply of silver paste 200 needs to be stable and sufficient to ensure the continuous printing and good filling effect of the gate line. The increase in the line width of the third gate line hole 331 allows more silver paste 200 to be accommodated during printing. When the doctor blade 100 scrapes on the surface of the steel plate, the third gate line hole 331 can store a certain amount of silver paste 200, avoiding problems such as broken gate line and insufficient filling due to insufficient supply of silver paste 200. This is like setting a "silver paste storage" during printing, which can supplement the silver paste 200 needed for printing in time to ensure the smooth progress of printing.

[0054] Further, the material of the buffer metal layer 31 is tin, tin alloy or aluminum. By using special process, one or more buffer metal layers 31 are formed on the surface of the first metal layer 32 of the patterned steel plate 3 in stages. Tin has good ductility and plasticity, and is relatively soft at room temperature, which makes it well adapted to the unevenness of the surface of the silicon wafer. When the patterned steel plate 3 contacts the silicon wafer for printing, the buffer metal layer 31 made of tin can deform to a certain extent, filling the small gaps between the steel plate and the silicon wafer, thereby preventing the silver paste 200 from overflowing from these gaps and ensuring the printing quality of the grid lines. In addition, tin also has a certain electrical conductivity, although its electrical conductivity is slightly weaker than that of silver and other metals, but in battery printing, it can play a good buffering and transitional role without affecting the overall electrical performance of the battery. Tin alloy is an alloy material formed by adding other metal elements to tin. By adjusting the alloy composition, the performance of the buffer metal layer 31 can be further optimized. For example, adding an appropriate amount of copper can improve the hardness and strength of the tin alloy while maintaining a certain ductility, so that it can better withstand the pressure of the squeegee 100 during printing and adapt to the unevenness of the surface of the silicon wafer. Different tin alloy formulations can be customized according to specific printing requirements and battery types to meet diverse production needs. Aluminum also has many characteristics suitable for the material of the buffer metal layer 31. It is light in weight and low in cost, which has certain economic advantages in large-scale production. Moreover, the surface of aluminum is easy to form a dense layer of aluminum oxide protective film, which can prevent aluminum from being corroded during printing, improving the stability and service life of the buffer metal layer 31. At the same time, aluminum also has a certain softness, which can well adhere to the surface of the silicon wafer during printing, ensuring the precision of printing and the quality of the grid lines.

[0055] In terms of the formation process of the buffer metal layer 31, multiple adsorptions are performed on the surface of the first metal layer 32 of the patterned steel plate 3 in stages to form one or more buffer metal layers 31. This process of multiple adsorptions in stages has many advantages. The adsorption is performed in stages to accurately control the thickness and uniformity of each buffer metal layer 31. During each adsorption process, it is ensured that each buffer metal layer 31 uniformly covers the surface of the first metal layer 32, avoiding local over-thickness or under-thickness. This is crucial for ensuring the overall performance of the buffer metal layer 31, as uniform thickness ensures that the buffer metal layer 31 can uniformly deform under stress during printing and better adapt to the unevenness of the silicon wafer surface. Multiple adsorptions can increase the total thickness of the buffer metal layer 31, further improving its buffering effect. Depending on different printing requirements and the unevenness of the silicon wafer surface, different numbers of buffer metal layers 31 can be selected for adsorption. For example, for a silicon wafer with a large surface unevenness, the number of adsorptions can be appropriately increased to form a thicker buffer metal layer 31 to better fill the gap between the steel plate and the silicon wafer; for a relatively flat silicon wafer, the number of adsorptions can be reduced to ensure the buffering effect while reducing production costs. In addition, this special process can also improve the bonding force between the buffer metal layer 31 and the first metal layer 32. During each adsorption process, the metal atoms of the buffer metal layer 31 interact with the metal atoms of the first metal layer 32 to form certain chemical bonds or physical adsorption forces. Through multiple adsorptions, this bonding force is continuously enhanced, allowing the buffer metal layer 31 to firmly adhere to the surface of the first metal layer 32 and not easily fall off during printing, ensuring the stability and reliability of printing.

[0056] Further, the material of the first metal layer 32 is nickel or nickel alloy. As a metal with excellent properties, nickel has high strength, high hardness, and good corrosion resistance. During battery printing, the patterned steel plate 3 needs to withstand the pressure applied by the doctor blade 100 and repeated friction. The high strength and high hardness of nickel make the first metal layer 32 effectively resist these external forces, maintain its shape and structure stability, and not easily deform or wear. This not only ensures the dimensional accuracy of the grid holes during printing, but also prolongs the service life of the patterned steel plate 3 and reduces the production cost of the enterprise. Nickel alloy is an alloy material formed by adding other metal elements to nickel. By adjusting the alloy composition, the performance of the first metal layer 32 can be further optimized. For example, adding an appropriate amount of chromium can improve the corrosion resistance of the nickel alloy, allowing it to maintain good performance in humid, acidic, and other harsh environments, which is crucial for long-term stable operation of battery printing equipment. Different nickel alloy formulations can be customized according to specific printing requirements and battery types to meet diverse production needs.

[0057] Further, the thickness of the buffer metal layer 31 is not greater than the thickness of the first metal layer 32. When the buffer metal layer 31 cools down, since the metal material will shrink during the cooling process, if the thickness of the buffer metal layer 31 is too large, the stress generated by the shrinkage of the buffer metal layer 31 may be transmitted to the first metal layer 32, causing the surface of the first metal layer 32 to generate bending stress. Such bending stress will affect the flatness of the patterned steel plate 3, and further affect the printing quality. For example, during the printing process, if the first metal layer 32 is bent due to the stress generated by the cooling of the buffer metal layer 31, the scraper 100 will not be able to uniformly press the surface of the steel plate when it is scraped, resulting in uneven deposition of the silver paste 200, and problems such as distortion of the grid lines, uneven thickness, etc. Controlling the thickness of the buffer metal layer 31 to be not greater than the thickness of the first metal layer 32 can effectively avoid such situations, ensuring that the patterned steel plate 3 remains flat during the printing process, and ensuring that the quality of the printed grid lines meets the requirements.

[0058] From the perspective of reducing the overall thickness of the patterned steel plate 3 and achieving lightweight, as the demand for equipment miniaturization and lightweight in the solar cell industry continues to increase, reducing the overall thickness of the patterned steel plate 3 has important practical significance. The thickness of the buffer metal layer 31 is not greater than the thickness of the first metal layer 32, which helps to reduce the thickness of the patterned steel plate 3 as much as possible while ensuring the buffering effect. Lightweight patterned steel plate 3 not only reduces the overall weight of the equipment, reducing transportation and installation costs, but also improves the flexibility and operability of the equipment. For example, in some printing equipment with high space requirements, lightweight patterned steel plate 3 can be more easily installed and debugged, improving production efficiency. In addition, reducing weight can also reduce energy consumption during equipment operation.

[0059] Exemplarily, the thickness of the buffer metal layer 31 is 1 μm-6 μm; and / or the thickness of the first metal layer 32 is 5 μm-15 μm.

[0060] Exemplarily, the material of the second metal layer 33 is nickel or nickel alloy; and / or the thickness of the second metal layer 33 is 5 μm-20 μm. The effect of using nickel or nickel alloy for the second metal layer 33 is similar to that of using nickel or nickel alloy for the first metal layer 32, and will not be described in detail here.

[0061] Exemplarily, the material of the ring-shaped auxiliary component 2 is nylon mesh. The high-strength characteristics of nylon mesh enable it to easily cope with external forces without being prone to breaking or deforming. Even under long-term, high-intensity printing operations, nylon mesh can maintain a stable structure, ensuring the normal use of the ring-shaped auxiliary component 2. At the same time, its good toughness allows nylon mesh to undergo a certain degree of elastic deformation when subjected to external force impact, absorbing energy and reducing damage caused by impact, further extending the service life of the ring-shaped auxiliary component 2.

[0062] Exemplarily, the frame 1 further comprises a plurality of positioning holes 13 which are circumferentially spaced apart on the fixed edge 11. The frame 1 is made of high-strength alloy material, has good rigidity and corrosion resistance, and ensures that no deformation occurs during printing. The frame 1 has precise positioning holes 13 around the frame 1, which ensures the consistency of the printing position each time.

[0063] In summary, in actual use, the full opening steel plate with the buffer metal layer 31 has a 15% single reduction in the rate of silicon wafer hidden crack defects, a 35% reduction in the rate of grid line expansion defects, effectively increases the service life of the steel plate, reduces the degradation or scrap of the silicon wafer caused by hidden cracks, and effectively reduces the cost. In the Topcon cell 400 printing process, the full opening steel plate with the buffer metal layer 31 has a 38% reduction in the proportion of cell degradation caused by grid line expansion compared to the steel plate without the buffer metal layer 31, while the service life is increased to 1.5-2 times the original, the silver paste 200 unit consumption is also more stable, which is 3-5 mg lower than the steel plate without the buffer layer, the conversion efficiency is increased by 0.1%, and the cost is effectively reduced.

[0064] Note that the above is only a preferred embodiment of the present application and the technical principle applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and those skilled in the art can make various obvious changes, readjustments and substitutions without departing from the scope of the present application. Therefore, although the present application has been described in more detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the appended claims.

Claims

1. A full opening steel plate for battery printing with a buffer metal layer, characterized in that, The application relates to a frame (1) comprising a fixed edge (11) which is circumferentially provided with a mounting area (12); an annular auxiliary material piece (2) located in the mounting area (12), wherein the outer edge of the annular auxiliary material piece (2) is connected with the fixed edge (11), and the inner edge of the annular auxiliary material piece (2) is circumferentially provided with a relief area (21); and a graphic steel plate (3) arranged on the annular auxiliary material piece (2), wherein the relief area (21) is larger than a graphic area of the graphic steel plate (3), the graphic steel plate (3) comprises a buffer metal layer (31) and a first metal layer (32), the graphic area of the buffer metal layer (31) is provided with a plurality of first grid line holes (311), the graphic area of the first metal layer (32) is provided with a plurality of second grid line holes (321), the printing surface of the first metal layer (32) is provided with at least one buffer metal layer (31), the first grid line hole (311) is in communication with the corresponding second grid line hole (321), and the hardness of the buffer metal layer (31) is smaller than the hardness of a silicon wafer. The graphic steel plate (3) further comprises a second metal layer (33), the graphic area of the second metal layer (33) is provided with a plurality of third grid line holes (331), the second metal layer (33) is arranged on the scraping surface of the first metal layer (32), and the third grid line hole (331) is in communication with the corresponding second grid line hole (321) and first grid line hole (311) in sequence. The opening line width of the first grid line hole (311) is the same as that of the second grid line hole (321), and the opening line width of the third grid line hole (331) is larger than that of the second grid line hole (321). The material of the buffer metal layer (31) is metal tin, tin alloy or metal aluminum.

2. The battery printing belt full opening steel version with buffer metal layer according to claim 1, characterized in that, The material of the first metal layer (32) is nickel or nickel alloy. The thickness of the buffer metal layer (31) is not larger than that of the first metal layer (32).

3. The battery printing belt full opening steel version with buffer metal layer according to claim 2, characterized in that, The thickness of the buffer metal layer (31) is 1-6 micrometers; and / or the thickness of the first metal layer (32) is 5-15 micrometers.

4. The battery printing belt full opening steel version with buffer metal layer according to claim 3, characterized in that, The material of the second metal layer (33) is nickel or nickel alloy; and / or the thickness of the second metal layer (33) is 5-20 micrometers.

5. The battery printing belt full opening steel version with buffer metal layer according to claim 4, characterized in that, The material of the annular auxiliary material piece (2) is nylon net.

6. The battery printing belt full opening steel version with buffer metal layer according to claim 5, characterized in that, The frame (1) further comprises a plurality of positioning holes (13) which are circumferentially and spacedly arranged on the fixed edge (11).

7. The battery printing belt full opening steel version with buffer metal layer according to claim 5, characterized in that, ​ ​ 8. The battery printing belt full opening steel version with buffer metal layer according to claim 2, characterized in that, ​ ​ 9. The full opening steel plate for battery printing with a buffer metal layer according to any one of claims 2 to 8, characterized in that, ​ 10. The battery printing belt full opening steel version with buffer metal layer according to claim 9, characterized in that, ​

Images