Wet type developing fluid tool mechanism
By arranging reciprocating and fixed spray components with asynchronous spraying above and/or below the cell transmission line and adopting a mixed fluid control mode, the problems of broken grids and uneven pattern size in the wet process are solved, and clear development of the electroplated grid lines and high yield of the cell are achieved.
Patent Information
- Application Number
- CN202422547089.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-22
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-10-22
AI Technical Summary
The existing wet process makes it difficult to achieve fine-line and highly uniform electroplating on battery cells, resulting in problems such as broken grids, uneven pattern sizes, and hidden cracks in battery cells. Traditional spray pressure has little effect on improving this.
A wet developing fluid tooling mechanism is adopted, which uses at least one group of reciprocating spray components and at least one group of fixed spray components above and/or below the battery cell transmission line. The spray components spray asynchronously, and multiple groups of nozzles are provided on the spray components. The spray direction is perpendicular to the direction of travel of the battery cell. A mixed fluid control mode is adopted to provide a high-flow and high-exchange fluid environment to ensure uniform contact between the liquid and the surface of the battery cell.
The electroplating grid lines are clearly developed and have good overall consistency, which improves the yield rate, solves the problems of electroplating grid breakage and uneven pattern size, and avoids hidden cracks in the battery cells.
Smart Images
Figure CN223481315U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of battery cell electroplating manufacturing technology, and in particular relates to a wet developing fluid tooling mechanism. Background Technology
[0002] Currently, the mass production of crystalline silicon solar cells in the solar energy industry uses silver paste printed on the surface and then sintered to form the metal grid lines (electrodes). However, this method produces electrode grid lines with a small aspect ratio (an average width of 30-50µm after sintering, and a height of approximately 10-15µm). This small aspect ratio results in an excessively large shading area on the solar cell (4-5% shading area on the front side); in addition, the silver paste is expensive (currently, silver paste costs approximately 8,000 yuan or more per kilogram). Therefore, improving efficiency and reducing production costs are the most pressing issues for all solar cell manufacturers.
[0003] The change in solar cell manufacturing process and structure involves replacing the traditional conductive silver paste process with electroplated metal grid lines. One key focus is the use of photolithography to create fine-line patterns, reducing the width of currently mass-produced printed grid lines from 40µm to 15µm or even less, thus minimizing the shading area of the metal grid lines. Furthermore, the reduced contact area between the semiconductor and the metal conductor decreases the recombination surface, thereby increasing minority carrier lifetime. The low resistance of electroplated copper (1 / 4 to 1 / 3 that of conductive silver paste) also reduces the series resistance of the solar cell (by 10-30%). Ultimately, this achieves the goal of cost reduction and efficiency improvement.
[0004] One of the most crucial equipment aspects is the introduction of wet processing. Currently, wet processing for solar cells primarily involves cleaning, etching, and texturing on the entire surface of the cell. However, when introducing copper metal electrode preparation, the area to be electroplated must first be patterned using photolithography before electroplating deposition. Therefore, when the pattern opening becomes finer and more complex (for example, the metal electrode is polygonal, such as a regular hexagon or quadrilateral, rather than the currently common single-line design), conventional wet processing equipment / devices are insufficient to meet requirements such as fine lines and high uniformity. The fundamental reason is that various characteristics, such as mask thickness, pattern width, chemical properties (specific gravity, viscosity, etc.), and the working methods of hardware components and workpiece movement, prevent fresh chemicals from being sprayed onto the cell surface. These characteristics hinder the chemical reaction, resulting in a pooling effect. Specifically, this manifests as uneven opening sizes in the mask pattern, meaning the dimensions of the pattern on the four sides are inconsistent with those in the center, sometimes being too large or too small, or even incomplete, resulting in significant differences in overall uniformity. These issues can lead to excessively large shaded areas in the final solar cell or incomplete pattern formation, causing problems such as broken grids during electroplating. All of these factors affect the final conversion efficiency of the solar cell.
[0005] Industry experts have attempted to improve the situation by increasing the spray pressure, but with limited success. The main reason is that increasing the spray pressure doesn't address the fundamental issue of uniform contact; instead, it exacerbates the unevenness within the solar cell. Furthermore, although the solar cells are covered by a mask, excessive spray pressure can still cause impact stress, leading to breakage or microcracks. Alternatively, excessive spray pressure can cause the solar cells to deviate during transport, colliding with the guide rails and resulting in breakage or microcracks. Summary of the Invention
[0006] This application provides a wet developing fluid tooling mechanism, which solves the technical problems in the prior art that easily produce electroplating grid breaks or poor overall uniformity of pattern size, as well as microcracks or fragments in the battery cells.
[0007] To solve at least one of the above-mentioned technical problems, the technical solution adopted in this application is:
[0008] A wet developing fluid fixture includes at least one set of reciprocating jetting components one and at least one set of fixed jetting components two disposed above and / or below a solar cell transport line, wherein the first jetting component one and the second jetting component two jet out asynchronously; wherein,
[0009] The jet component is provided with several jet pipes equipped with multiple sets of nozzles;
[0010] The jet component 2 is provided with several jet pipes 2 equipped with multiple sets of nozzles;
[0011] The first nozzle and the second nozzle are arranged in the same direction, and are alternately arranged with the second nozzle.
[0012] Furthermore, the length direction of the nozzle is perpendicular to the direction of travel of the battery cell.
[0013] Furthermore, the movement trajectory of the jet component one is to reciprocate in a direction perpendicular to the direction of travel of the battery cell, or to move in a circle within the area where the battery cell travels.
[0014] Furthermore, in the jet component one, all of the jet pipes one are constructed as independently installed pipes.
[0015] Furthermore, in the jet component one, adjacent jet pipes one are interconnected.
[0016] Furthermore, the distance between the first jet component and the second jet component is 1-10cm;
[0017] Preferably, the spacing is 3cm.
[0018] Furthermore, the distance between the nozzle and the battery cell is 1-15cm.
[0019] Preferably, the distance is 5cm.
[0020] Furthermore, the distance between adjacent nozzles is not greater than 1 / 4 of the width of the battery cell and not less than 1 / 10 of the width of the battery cell;
[0021] Preferably, the distance between adjacent nozzles is no greater than 1 / 5 of the width of the battery cell.
[0022] Furthermore, the shape of the liquid ejected from the nozzle includes a droplet, a column, a fan, or a cone; the flow pattern of the liquid ejected from the nozzle is intermittent or continuous.
[0023] Furthermore, the mask pattern in the battery cell is configured along the length direction of the battery cell or along the width direction of the battery cell.
[0024] The wet developing fluid fixture designed in this application adopts a mixed fluid control mode to provide a high-flow and high-exchange fluid environment for the solar cells, so that the liquid is in uniform and sufficient contact with the surface of the solar cells, generating sufficient chemical reaction, resulting in clear development of electroplated grid lines and good overall consistency, ensuring product surface quality and improving yield. Attached Figure Description
[0025] Figure 1This is a perspective view of the wet developing fluid fixture mechanism in this application;
[0026] Figure 2 This is a side view of the wet developing fluid tooling mechanism in this application;
[0027] Figure 3 This is a simplified schematic diagram of one of the mask patterns in this application and the direction of the battery cell's movement;
[0028] Figure 4 This is a simplified schematic diagram of one of the mask patterns in this application and the direction of the battery cell's movement;
[0029] Figure 5 This is a layout diagram of one type of mixed jet in this application;
[0030] Figure 6 yes Figure 5 A simplified schematic diagram of the mixed jet stream;
[0031] Figure 7 This is a layout diagram of another mixed jet stream in this application;
[0032] Figure 8 yes Figure 7 A simplified schematic diagram of the mixed jet stream;
[0033] Figure 9 This is a layout diagram of another type of mixed jet stream in the application;
[0034] Figure 10 This is a schematic diagram of fluid flow on the battery cell in a fixed jet configuration in the prior art;
[0035] Figure 11 This is a schematic diagram of the fluid flow on the battery cell during the mixed jet flow in this application;
[0036] Figure 12 It is an incomplete graphic photograph obtained by etching using an existing fixed jet stream.
[0037] Figure 13 It is a uniform graphic photograph obtained by etching after mixing the jets in this application;
[0038] Figure 14 It is an uneven graphic photograph obtained by developing using an existing fixed jet stream;
[0039] Figure 15 It is a uniform graphic photograph obtained by developing the mixed jets as described in this application.
[0040] In the picture:
[0041] 10. Battery cell; 20. Jet jet component; 21. Jet jet pipe.
[0042] 22. Fixture 1; 30. Jet Component 2; 31. Jet Pipe 2
[0043] 32. Fixture 2; 40. Nozzle; 50. Movement control component
[0044] 60. Mask pattern Detailed Implementation
[0045] The present application will now be described in detail with reference to the accompanying drawings and specific embodiments.
[0046] This embodiment proposes a wet developing fluid fixture mechanism, such as... Figure 1 As shown, the device includes at least one set of reciprocating jet components 20 and at least one set of fixed jet components 30 disposed above and / or below the cell transmission line 10. That is, the fluid tooling mechanism is provided with at least one set of reciprocating jet components 20 and at least one set of fixed jet components 30, which can be respectively disposed above and below the cell transmission line, for wet development of both sides of the cell, such as... Figure 2 As shown. Alternatively, the fluid tooling mechanism can be located only above the cell transport line or only below the cell transport line. Both of these structures perform wet development on only one side of the cell. (See attached diagram.)
[0047] This application uses a wet development operation on both sides of a solar cell as an example. The two jetting components, 20 and 30, located above and below the solar cell transport line, have identical structures. However, the jetting components 20 and 30 on the same side are asynchronous. First, a fixed jetting operation is performed on the solar cell surface, spraying fluid evenly to initiate a chemical reaction. Then, a reciprocating jetting operation is used to further provide more effective anisotropic fluid spraying, allowing the fluid to flow in multiple directions to improve reaction exchange efficiency and achieve uniform and comprehensive flow contact. This hybrid fluid control mode of fixed and reciprocating jetting provides a high-flow and high-exchange fluid environment for the solar cell, ensuring uniform and sufficient contact between the liquid and the cell surface, generating sufficient chemical reaction. This results in clear development of the electroplated grid lines with good overall consistency, guaranteeing product surface quality and improving yield.
[0048] The first jet component 20 has several jet pipes 21 equipped with multiple sets of nozzles 40, and the length direction of the jet pipes 21 is perpendicular to the travel direction of the battery cell 10. All jet pipes 21 are interconnected and form a whole. On the side of the jet pipes 21 away from the battery cell, there is a fixing member 22 perpendicular to the length direction of the jet pipes 21, and the fixing member 22 is located at both ends of the jet pipes 21. Correspondingly, the second jet component 30 has several jet pipes 31 equipped with multiple sets of nozzles 40. Similar to the structure of the first jet component 20, the second jet pipe 31 also has two parallel fixing members 32 perpendicular to its length direction on the side away from the battery cell, and the fixing members 32 are located at both ends of the jet pipe 31. Both the innermost fixing member 21 and the fixing member 31 are equipped with a movement control member 50 for controlling the movement of the jet pipe. For the fixed jet component 30, the movement control member 50 that works with it does not need to work during the entire operation.
[0049] Fixing member 22 and fixing member 32 are both devices used to fix jet component 20 and jet component 30. On the same end side, fixing member 22 and fixing member 32 are placed adjacent to each other. Along the direction perpendicular to the travel direction of the battery cell, that is, along the length direction of the jet pipe, fixing member 22 and fixing member 32 are staggered, so that the two sets of mixed jet components 20 and jet component 30 are arranged in an interlocking structure. This allows jet pipe 21 and jet pipe 31 to be configured in the same direction, and jet pipe 21 and jet pipe 31 to be arranged alternately, which can improve the consistency and uniformity of the jet effect.
[0050] like Figure 3 As shown, the opening direction of the mask pattern 60 is set along the traveling direction of the battery cell 10, that is, along the length direction of the battery cell. The lower diagram is a top view of the battery cell 10 and the mask pattern 60 in conjunction; its cross-sectional schematic diagram is shown in the upper diagram. From this example, it can be seen that the area in the middle region, as indicated by the ellipse in the diagram, is the weak exchange / reaction zone, while the areas on both sides are the complete exchange / reaction zones.
[0051] like Figure 4 As shown, the opening direction of the mask pattern 60 is set perpendicular to the traveling direction of the solar cell 10, that is, along the width direction of the solar cell. Figure 3 The structure is similar. The illustration below is a top view of the battery cell 10 and the mask pattern 60 in conjunction; its cross-sectional schematic diagram is shown in the illustration above; as can be seen from the example position, the position in the middle region as shown by the ellipse in the figure is the weak exchange / reaction region, and the two sides are the complete exchange / reaction regions.
[0052] In both mask patterns 60, for the case of a fixed jet, within the region on the solar cell, the four sides of the cell will continuously react as liquid flows out, allowing fresh liquid to continuously contact the cell. In other words, the reaction effect in the area of these four sides will be closest to the desired design dimensions / morphology. However, in the central region of the solar cell, as circled by the dotted line in the figure, due to the specific gravity, viscosity, and other characteristics of the liquid, the flow is slow or the exchange is least complete. This means that the reaction in the central region will be incomplete. Consequently, the process effect between the edges and the central region of the solar cell will differ significantly, resulting in a large difference in overall uniformity.
[0053] like Figure 10 The diagram shows a simplified representation of the fluid flow direction on the solar cell during a fixed-point spray. As can be seen, the fluid flows along the mask opening and in the opposite direction to the solar cell's movement. Because the fixed-point spray is a single-pressure jet, although the solar cell's forward movement provides some shear force to drive the flow, the flow rate is limited by factors such as the cell's thickness, drift, and the overall reaction time required for the process (typically ranging from 1-4 m / min). This means that as the opening size of the mask pattern 60 decreases, incomplete or obstructed liquid flow or exchange may occur.
[0054] like Figure 11 The diagram shows a simplified representation of the fluid flow direction on the solar cell when using a hybrid fluid control mode. As can be seen, the fluid flow direction is not only along the direction of the solar cell's movement, but also includes a reciprocating jet flow direction, as indicated by the thick blue arrows, perpendicular to the solar cell's movement. This demonstrates that the fixed jet and hybrid jet methods result in more diverse fluid flow directions. While ensuring sufficient contact with the solar cell surface, this further improves the liquid exchange effect, resulting in a more complete and uniform reaction between the liquid and the solar cell. In contrast, the reciprocating spray fluid control method produces a continuous S-shaped liquid trajectory rather than a fixed, continuous straight line. This allows the reacted liquid to quickly leave the solar cell 10, while fresh liquid continues to react and exchange with it. This allows for more complete liquid flow and exchange, achieving the desired process design more effectively.
[0055] like Figure 5 As shown, in the jet component 20, all jet pipes 21 are constructed as independently installed pipes, and their structural diagram is as follows. Figure 6 As shown.
[0056] like Figure 7 As shown, in the jet component 20, adjacent jet pipes 21 are interconnected, and their corresponding structural diagram is as follows. Figure 8 As shown.
[0057] Regardless of Figure 5-6 The design structure of the nozzle pipe 21 is still as described. Figure 7-8 In the aforementioned design structure, the distance X1 between two adjacent sets of jet component 20 and jet component 30 is 1-10cm, preferably 3cm. Furthermore, the height distance between the nozzle 40 and the battery cell 10 is 1-15cm; preferably 5cm. Simultaneously, for each jet pipe, the distance between adjacent nozzles is no greater than 1 / 4 and no less than 1 / 10 of the battery cell width; preferably, the distance between adjacent nozzles is no greater than 1 / 5 of the battery cell width.
[0058] like Figure 6 , 8 As shown, the movement trajectory of the jet component 20 is a reciprocating movement in a direction perpendicular to the travel direction of the battery cell 10.
[0059] like Figure 9 As shown, the movement trajectory of the jet component 20 is a circular movement within the area where the battery cell travels. This circular movement can be a clockwise rotation or a counterclockwise rotation.
[0060] Furthermore, the shape of the liquid ejected from the nozzle 40 includes a droplet, a column, a fan, or a cone, which is common knowledge in the art, and the figures are omitted; and the flow pattern of the liquid ejected from the nozzle 40 is intermittent or continuous.
[0061] For each component in the reciprocating jet component 20, the materials used in its fabrication are all materials possessing chemical corrosion resistance, temperature resistance, processability, and rigidity with load-bearing capacity, including but not limited to PVDF, PP, PVD, ABS, PE, and HDPE. The moving speed V of the jet component 20... jet Not greater than the speed of the battery cell V cell Twice that of the solar cell travel speed V, and not less than the solar cell travel speed V. cell 0.5 times. Preferably, the moving speed V of the jet component 20 is... jet With the speed V of the battery cell cell Similarly, a 45° flow shear stress is formed, at which point the fluid can have the maximum flow force to carry away liquid.
[0062] For each component in the fixed jet component 2 30, the materials used to prepare them are all materials with chemical corrosion resistance, temperature resistance, processability and load-bearing rigidity, including but not limited to PVDF, PP, PVD, ABS, PE and HDPE.
[0063] The liquids conveyed by jet component 1 20 and jet component 2 30 include chemicals and cleaning liquids such as deionized water and RO water, and can also be reaction gases or drying gases required for the process.
[0064] A comparison was made between the operation proposed in this application, which involves a fixed jet followed by a reciprocating jet, and the operation using a fixed jet in the prior art, and the results obtained are as follows: Figure 12-13 Graphical photographs of the etching process shown and such Figure 14-15 The development process images shown clearly demonstrate that the etching images obtained using the existing fixed jet operation exhibit incomplete patterns and visible grid breaks after development. In contrast, the mixed jet operation proposed in this application yields more uniform etching process images with better development results.
[0065] It is evident that the wet developing fluid tooling mechanism designed in this application adopts a mixed fluid control mode, providing a high-flow and high-exchange fluid environment for the solar cells, so that the liquid is in uniform and sufficient contact with the surface of the solar cells, generating sufficient chemical reactions, resulting in clear development of electroplated grid lines and good overall consistency, ensuring product surface quality and improving yield.
[0066] The embodiments of this application have been described in detail above. These descriptions are merely preferred embodiments and should not be construed as limiting the scope of this application. All equivalent variations and modifications made within the scope of this application should still fall within the patent coverage of this application.
Claims
1. A wet developing fluid fixture mechanism, characterized in that, It includes at least one set of reciprocating jet components one and at least one set of fixed jet components two disposed above and / or below the battery cell transmission line, wherein the jet components one and the jet components two spray asynchronously; wherein, The jet component is provided with several jet pipes equipped with multiple sets of nozzles; The jet component 2 is provided with several jet pipes 2 equipped with multiple sets of nozzles; The first nozzle and the second nozzle are arranged in the same direction, and are alternately arranged with the second nozzle.
2. The wet developing fluid fixture mechanism according to claim 1, characterized in that, The length direction of the nozzle is perpendicular to the direction of travel of the battery cell.
3. A wet developing fluid fixture mechanism according to claim 1 or 2, characterized in that, The movement trajectory of the jet component one is to reciprocate in a direction perpendicular to the direction of travel of the battery cell, or to move in a circle within the area where the battery cell travels.
4. The wet developing fluid fixture mechanism according to claim 3, characterized in that, In the jet component one, all the jet pipes one are constructed as independently installed pipes.
5. The wet developing fluid fixture mechanism according to claim 3, characterized in that, In the jet component one, adjacent jet pipes are interconnected.
6. A wet developing fluid fixture mechanism according to any one of claims 1-2 and 4-5, characterized in that, The distance between the first jet component and the second jet component is 1-10cm.
7. A wet developing fluid fixture mechanism according to claim 6, characterized in that, The spacing is 3cm.
8. A wet developing fluid fixture mechanism according to claim 6, characterized in that, The nozzle is positioned at a height 1-15cm above the battery cell.
9. A wet developing fluid fixture mechanism according to claim 8, characterized in that, The distance is 5cm.
10. A wet developing fluid fixture mechanism according to claim 6, characterized in that, The distance between adjacent nozzles is no greater than 1 / 4 of the width of the battery cell and no less than 1 / 10 of the width of the battery cell.
11. A wet developing fluid fixture mechanism according to claim 10, characterized in that, The distance between adjacent nozzles is no greater than 1 / 5 of the width of the battery cell.
12. A wet developing fluid fixture mechanism according to any one of claims 7-11, characterized in that, The shape formed by the liquid ejected from the nozzle includes a droplet, a column, a fan, or a cone; the flow pattern of the liquid ejected from the nozzle is intermittent or continuous.
13. The wet developing fluid tooling mechanism according to claim 1, characterized in that, The mask pattern in the battery cell is configured along the length direction of the battery cell or along the width direction of the battery cell.