Multi-layer full-open steel plate and manufacturing method for multi-layer full-open steel plate

Abstract

A multi-layer full-open steel plate and a manufacturing method for a multi-layer full-open steel plate. The multi-layer full-open steel plate comprises a plurality of stacked shaping layers (100) and a framework layer (200) arranged on the uppermost shaping layer (100). An ink storage channel (300) is formed by shaping patterns on the plurality of shaping layers (100), so that the amount of ink passing through the ink storage channel (300) is significantly increased compared with a single-layer structure used by a conventional full-open steel plate, thereby ensuring that during narrow linewidth printing, paste pushed by a squeegee can continuously infiltrate into mesh holes and is stably transferred to a cell, thus ensuring that the supply of the paste is sufficient during printing, so as to ensure full plasticity of fingers and reduce the finger interruption rate.

Description

Multi-layer fully open steel plate and its preparation method

[0001] This application claims priority to Chinese Patent Application No. 202510484866.2, filed with the Chinese Patent Office on April 17, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of electrode printing technology, for example to a multilayer fully open steel plate and a method for preparing the multilayer fully open steel plate. Background Technology

[0003] In the field of photovoltaic cell manufacturing, with the development of high-efficiency cell technologies such as tunnel oxide passivated contact (TOPCon) cells and heterojunction solar cells (HJT), narrow linewidth printing processes (such as TOPCon cells with fine grid lines ≤6 micrometers) have placed higher demands on the precision of printing plates in order to reduce electrode resistance loss through finer grid lines, thereby improving cell conversion efficiency.

[0004] However, traditional fully open steel plates usually adopt a single-layer structure. When applied to narrow line width printing, the effective ink volume of the single-layer mesh decreases significantly as the line width decreases, resulting in insufficient ink supply during the printing process. Under the pressure of the squeegee, the ink is difficult to fully fill the mesh and transfer to the surface of the solar cell, resulting in insufficient plasticity of the grid lines and an increased proportion of broken grids. Summary of the Invention

[0005] This application provides a multi-layer fully open steel plate and a method for preparing the multi-layer fully open steel plate to ensure sufficient ink supply during the printing process, thereby ensuring full plasticity of the grid lines and reducing the proportion of broken grid lines.

[0006] This application provides a multi-layer fully open steel plate, the multi-layer fully open steel plate comprising multiple stacked shaping layers and a skeleton layer disposed above the uppermost shaping layer, wherein:

[0007] Each of the plurality of shaping layers is formed with a shaped pattern, and the shaped patterns together form an ink storage channel that can temporarily store ink during printing.

[0008] The skeleton layer forms an ink-permeable pattern, which corresponds one-to-one with each of the shaped patterns. The opening width of the ink-permeable pattern is greater than the opening width of each of the shaped patterns.

[0009] In some embodiments, the opening widths of the various shaped patterns are different, so that the sidewalls of the ink storage channels vary along a preset path.

[0010] In some embodiments, the opening width of each of the shaped patterns gradually decreases from top to bottom.

[0011] In some embodiments, the opening width of each of the shaped patterns gradually increases from top to bottom.

[0012] In some embodiments, the skeleton layer is made of metal.

[0013] In some embodiments, the plurality of shaping layers are integrally formed on the skeleton layer.

[0014] This application also provides a method for preparing a multi-layer fully open steel plate, used to prepare the above-mentioned multi-layer fully open steel plate, the method comprising:

[0015] A framework layer is prepared by electroforming.

[0016] A shaping layer is prepared by growing the plurality of shaping layers on the skeleton layer using an electroplating process.

[0017] In some embodiments, prior to the preparation of the shaping layer, the method for preparing the multilayer fully open steel plate further includes:

[0018] Laser engraving or photolithography is used to create ink-transparent patterns on the skeleton layer.

[0019] In some embodiments, after the preparation of the shaping layer, the method for preparing the multilayer fully open steel plate further includes:

[0020] The flatness of the plurality of shaping layers and the skeleton layer is detected, and the opening width of each of the shaping patterns and the ink-transparent patterns is detected.

[0021] In some embodiments, after the preparation of the shaping layer, the method for preparing the multilayer fully open steel plate further includes:

[0022] Printing tests were conducted on the multi-layer fully open steel plate to verify its fatigue resistance by simulating the movement of a squeegee. Attached Figure Description

[0023] Figure 1 is a structural schematic diagram of the multi-layer fully open steel plate provided in this application;

[0024] Figure 2 is a schematic diagram of the structure of the multi-layer fully open steel plate provided in this application.

[0025] In the picture:

[0026] 100, Shaping layer; 200, Skeleton layer; 300, Ink storage channel. Detailed Implementation

[0027] Before explaining any implementation of this application in detail, it should be understood that this application is not limited to its application to the structural details and component arrangements set forth in the following description or shown in the above drawings.

[0028] In this application, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, 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 that element.

[0029] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. Additionally, the character " / " in this application generally indicates that the preceding and following related objects have an "and / or" relationship.

[0030] In this application, the terms "connection," "combination," "coupling," and "installation" can refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without the need for an intermediary, while an indirect connection refers to two parts or components each being connected to at least one intermediary, with the connection achieved through the intermediary. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.

[0031] In this application, those skilled in the art will understand that relative terms (e.g., “about,” “approximately,” “basically,” etc.) used in conjunction with quantities or conditions are to include the values ​​and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances associated with the particular value due to manufacturing, assembly, use, etc. Such terms should also be considered as disclosing a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​that do not use relative terms should also be disclosed as specific values ​​with tolerances. Furthermore, “basically” when expressing relative angular relationships (e.g., substantially parallel, substantially perpendicular) may refer to a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) added to or subtracted from the indicated angle.

[0032] In this application, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0033] In this application, the directional terms "upper," "lower," "left," "right," "front," and "rear" are used to describe the orientation and positional relationships shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when an element is mentioned as being connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, and rear side not only represent positive orientation but can also be understood as lateral orientation. For example, "below" can include directly below, lower left, lower right, lower front, and lower rear.

[0034] Referring to Figures 1 and 2, this embodiment provides a multi-layer fully open steel plate, which includes multiple stacked shaping layers 100 and a skeleton layer 200 disposed above the uppermost shaping layer 100. Each of the shaping layers 100 has a shaped pattern, which together form an ink storage channel 300 that temporarily stores ink during printing and transfers the ink to the surface of the battery cell through the ink storage channel 300. The skeleton layer 200 forms an ink-transmitting pattern, which corresponds one-to-one with each shaping pattern, and the opening width of the ink-transmitting pattern is larger than the opening width of each shaping pattern.

[0035] In some embodiments, it should be noted that the aforementioned shaped pattern can be understood as a hollow through-hole structure precisely processed on the shaped layer 100, with the opening contour matching the cross-sectional contour of the grid line to be printed; multiple shaped patterns are arranged vertically and horizontally, coaxially stacked, together forming an ink storage channel 300 that can temporarily store the ink during the printing process, and the ink is stably transferred to the surface of the battery cell through the ink storage channel 300. The ink-permeable pattern can be understood as a hollow through-hole structure precisely processed on the skeleton layer 200, with the opening contour corresponding to the opening contour of the shaped pattern, used to provide an inflow channel for the ink during the printing process, allowing the ink to smoothly enter the ink storage channel 300 below.

[0036] Referring to Figures 1-2, as a structural example of a multi-layer fully open steel plate, the multi-layer fully open steel plate includes three shaping layers 100 stacked along the thickness direction. The three shaping layers 100 are stacked sequentially and are all located between the skeleton layer 200 and the battery cell to be printed. The three shaping layers 100 are the first shaping layer, the second shaping layer, and the third shaping layer, respectively. Each shaping layer 100 has a corresponding shaping pattern. The three shaping patterns are arranged vertically and horizontally, coaxially, and together form an ink storage channel 300. The skeleton layer 200 is located on the side of the uppermost shaping layer 100 away from the battery cell. The ink-permeable pattern of the skeleton layer 200 corresponds one-to-one with the three shaping patterns and has a larger opening width so that the ink enters the ink storage channel 300 through the ink-permeable pattern and completes the printing transfer.

[0037] When the doctor blade scrapes across the surface of the skeleton layer 200, the paste first enters the opening of the ink-permeable pattern, and then converges into the ink storage channel 300 formed by the various shaped patterns. The paste pushed by the doctor blade can then continuously enter the ink storage channel 300, so that the paste can be printed stably and continuously onto the battery cell.

[0038] In this embodiment, the ink storage channel 300 is composed of various shaped patterns on multiple shaping layers 100. This significantly increases the ink throughput of the ink storage channel 300 compared to the single-layer structure used in traditional fully open steel plates. This ensures that during narrow linewidth printing, the ink pushed by the squeegee continuously wets the mesh and is stably transferred to the battery cell, thus guaranteeing sufficient ink supply during printing to ensure full plasticity of the grid lines and reduce the proportion of broken grids. In other words, by cooperating with the squeegee movement and the multi-layer mesh structure formed by multiple shaping layers 100, the "direct extrusion of ink" of the traditional single-layer steel plate is transformed into "controlled ink release through the ink storage channel 300," significantly improving the uniformity and reliability of ink transfer during narrow linewidth printing. Furthermore, it eliminates battery conversion efficiency losses caused by unstable ink supply, adapting to the manufacturing requirements of high-precision metallized electrodes for high-efficiency batteries such as TOPCon and HJT.

[0039] Due to design differences, different types of solar cells, such as shingled cells and half-cell cells, have increasingly diverse requirements for grid line shapes, such as arc shapes and variable cross-sections, which are not trapezoidal structures. The performance bottleneck of traditional fully open steel plates is gradually becoming apparent in practical applications.

[0040] Therefore, in this embodiment, the opening widths of each shaped pattern are different, so that the sidewalls of the ink storage channel 300 vary along a preset path. With this configuration, when the doctor blade squeezes the ink through the ink storage channel 300, the ink is constrained by the sidewalls, resulting in directional flow. This causes the outline of the grid lines to be limited by the width of the sidewalls of the ink storage channel 300 at various locations, thereby printing grid lines with specific line shapes. Compared to the traditional method of using steel plates and relying on post-processing adjustments to the line shape, this method offers higher precision control and consistency, and also higher processing efficiency.

[0041] For example, the opening width of each shaped pattern gradually decreases from top to bottom. Understandably, this gradual decrease in opening width creates a top-wide, bottom-narrow ink storage channel 300 structure, where the larger opening at the top can accommodate more ink, increasing ink storage capacity. Furthermore, during printing, the ink can flow more smoothly from the wider upper shaped pattern to the narrower lower one, ensuring sufficient ink is delivered to the cell surface during narrow linewidth printing, thus guaranteeing grid line fullness and reducing the proportion of broken grids. More importantly, because the opening width of the bottommost shaped layer 100 is smaller than that of the upper shaped layer 100, the ink typically breaks at the top surface of the bottommost shaped layer 100 when the stencil leaves the cell. Simultaneously, influenced by the friction of the stencil leaving and the viscosity of the ink, it ultimately shapes a frustum-shaped or cone-shaped grid line that is narrower at the top and wider at the bottom, meeting the design requirements of different cell types such as shingled and half-cell cells. For example, in shingled solar cells, the grid lines that are narrower at the top and wider at the bottom can reduce the shading area when stacking the cells, thereby improving the photoelectric conversion efficiency of the cells.

[0042] In other embodiments, the opening width of each shaped pattern gradually increases from top to bottom, resulting in the ink storage channel 300 being narrower at the top and wider at the bottom. When the steel plate leaves the battery cell, the slurry, due to its larger opening and ample ink storage space at the bottom, is subjected to viscous and frictional forces as it flows downwards. The slurry typically breaks off at the top surface of the uppermost shaped layer 100. Compared to the bottommost shaped layer 100 breaking off, this makes the grid sidewalls more vertical, avoiding truncated cone or conical inclined sidewalls. That is, the ink storage channel 300 is narrower at the top and wider at the bottom, and the slurry in the ink storage channel 300 is also roughly narrower at the top and wider at the bottom. When the steel plate leaves the battery cell, the larger amount of slurry at the bottom moves upwards due to viscous and frictional forces to compensate for the smaller amount of slurry at the top, thus making the grid lines more vertical and meeting the stringent requirements of high-efficiency batteries for vertical sidewall profiles. For example, the high aspect ratio grid lines of HJT batteries reduce the electrode shading area while improving current transmission efficiency.

[0043] To extend the service life of the multi-layer, fully open stencil, the skeleton layer 200 is made of metal. It is understood that metal possesses high tensile and compressive strength, preventing plastic deformation or fracture of the skeleton layer 200 under the high-frequency pressure load of the reciprocating motion of the squeegee. This ensures the long-term stability of key parameters such as the opening width and sidewall angle of the ink storage channel 300, thereby maintaining the consistency of grid line printing. Especially in narrow linewidth printing, the rigidity of the metal skeleton layer 200 can suppress localized collapse of the stencil caused by squeegee pressure, preventing poor ink flow or linear defects due to structural deformation. In this embodiment, the skeleton layer 200 is made of a nickel-based alloy. In other embodiments, the skeleton layer 200 can also be made of stainless steel, aluminum alloy, or other materials.

[0044] To enhance the structural strength of the multi-layer fully open steel plate, multiple shaping layers 100 are integrally molded onto the skeleton layer 200. Compared to the adhesive or welding methods used in multi-layer assembly, this design avoids peeling and misalignment caused by interlayer shear forces under the reciprocating pressure of the scraper and the dynamic load of the steel plate detaching from the battery cell at high speed. This ensures the long-term stability of the ink storage channel 300 and prevents grid line deviation caused by interlayer displacement.

[0045] This embodiment also provides a method for preparing the above-mentioned multi-layer fully open steel plate, the method comprising:

[0046] A framework layer 200 was prepared and deposited using an electroforming process.

[0047] A shaping layer 100 is prepared by electroplating multiple shaping layers 100 on the skeleton layer 200.

[0048] Electroforming, through electrochemical deposition, can achieve dimensional tolerances of ±1 micrometer for the skeleton layer 200. Compared to machining, this process offers higher precision, ensuring that the conductive paths and support structures of the skeleton layer 200 perfectly match the design model, providing a good reference for the shaping layer 100. Furthermore, electroplating can be used to grow shaping layers 100 of varying thicknesses and widths on the surface of the skeleton layer 200 by adjusting the current density, time, and electrolyte composition.

[0049] In some embodiments, to ensure the accuracy of the processing dimensions, the method for preparing the multi-layer fully open steel plate further includes: laser engraving or photolithography to create an ink-transparent pattern on the skeleton layer 200 before preparing the shaping layer 100.

[0050] Both laser engraving and photolithography can achieve sub-millimeter level precision machining. Laser engraving uses a focused laser spot to precisely delineate linewidths, while photolithography uses ultraviolet exposure combined with a mask to transfer linewidth patterns. Both far surpass traditional machining methods, meeting the miniaturization requirements of ink-transparent patterns. Furthermore, both laser engraving and photolithography avoid material deformation caused by mechanical contact, ensuring dimensional accuracy.

[0051] In some embodiments, to improve the yield of multi-layer fully open steel plates, after preparing the shaping layer 100, the preparation method of the multi-layer fully open steel plate further includes: detecting the flatness of the multiple shaping layers 100 and the skeleton layer 200, and detecting the opening width of each shaping pattern and ink-transmitting pattern.

[0052] The aforementioned detection methods can be selected from any relevant technology depending on the actual application scenario. For example, a laser level can be used to scan the surface being measured by a laser beam, receive the reflected light signals, calculate the height of each point on the surface, and construct a three-dimensional profile. Another example is the detection method combining scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). High-resolution SEM is used to observe the microscopic morphology of the opening edge and detect burrs or coating defects, while EDS simultaneously analyzes the elemental distribution.

[0053] In some embodiments, after preparing the shaping layer 100, the method for preparing the multi-layer fully open steel plate further includes: conducting a printing test on the multi-layer fully open steel plate, and verifying the fatigue resistance of the multi-layer fully open steel plate by simulating the movement of a squeegee. This setup, by simulating the reciprocating motion of a squeegee on the surface of the steel plate, directly replicates the mechanical stress borne by the steel plate during the printing process, exposes potential fatigue defects in advance, and avoids quality problems caused by steel plate fatigue failure in actual printing.

Claims

1. A multi-layer fully open steel plate, the multi-layer fully open steel plate comprising a plurality of stacked shaping layers (100) and a skeleton layer (200) disposed above the uppermost shaping layer (100), wherein: Each of the plurality of shaping layers (100) is formed with a shaping pattern, and the shaping patterns together form an ink storage channel (300) that can temporarily store the paste during printing, and transfer the paste to the surface of the battery cell through the ink storage channel (300). The skeleton layer (200) forms an ink-transparent pattern, which corresponds one-to-one with each of the shaped patterns. The opening width of the ink-transparent pattern is greater than the opening width of each of the shaped patterns.

2. The multi-layer fully open steel plate according to claim 1, wherein, The opening widths of each of the shaped patterns are different, so that the sidewalls of the ink storage channel (300) vary along a preset path.

3. The multi-layer fully open steel plate according to claim 2, wherein, The opening width of each of the aforementioned shaped shapes gradually decreases from top to bottom.

4. The multi-layer fully open steel plate according to claim 2, wherein, The opening width of each of the aforementioned shaped shapes gradually increases from top to bottom.

5. The multi-layer fully open steel plate according to claim 1, wherein, The skeleton layer (200) is made of metal.

6. The multi-layer fully open steel plate according to claim 5, wherein, The plurality of shaping layers (100) are integrally formed on the skeleton layer (200).

7. A method for preparing a multi-layer fully open steel plate, used to prepare a multi-layer fully open steel plate as described in any one of claims 1-6, comprising: A framework layer (200) is prepared and deposited by electroforming. A shaping layer (100) is prepared, and the plurality of shaping layers (100) are grown on the skeleton layer (200) by electroplating process.

8. The method for preparing a multi-layer fully open steel plate according to claim 7, wherein before preparing the shaping layer (100), the method further comprises: Laser engraving or photolithography is used to create ink-transparent patterns on the skeleton layer (200).

9. The method for preparing a multi-layer fully open steel plate according to claim 7, wherein after preparing the shaping layer (100), the method further comprises: The flatness of the plurality of shaping layers (100) and the skeleton layer (200) is detected, and the opening width of each of the shaping patterns and the ink-transparent patterns is detected.

10. The method for preparing a multi-layer fully open steel plate according to claim 7, wherein after preparing the shaping layer (100), the method further comprises: Printing tests were conducted on the multi-layer fully open steel plate to verify its fatigue resistance by simulating the movement of a squeegee.

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