A high life-span screen for printing BC battery and a preparation process thereof

Abstract

The application discloses a high-life screen for printing BC battery, comprising a metal substrate, at least one end surface of the metal substrate is provided with a polymer film layer, a flexible buffer layer is arranged between the polymer film layer and the metal substrate, and a pattern area is processed on the polymer film layer. A preparation process is also disclosed, comprising the following steps: S1, pulse anodic oxidation treatment is performed on a nickel substrate; S2, a flexible buffer layer is constructed through gas deposition; S3, a polymer film layer is prepared; and S4, a laser is used to process the polymer film layer in a pattern. The screen is designed with a gradient buffer layer to reduce interface stress and avoid deformation or falling off of the polymer layer and the base metal electroforming screen. The combination strength is greatly strengthened through a porous structure. The composite film layer screen is good in buffering effect during printing, long in service life, perfect in overall function and high in practicability.

Description

Technical Field

[0001] This invention relates to the field of printing screen technology, and more specifically, to a high-lifespan printing screen for BC batteries and its preparation process. Background Technology

[0002] BC cells, or full back contact (full reverse contact) crystalline silicon photovoltaic cells, are a type of solar cell technology. Due to their significant advantages in cell efficiency, high degree of grid line optimization, and simple packaging, they have gradually become the next generation of mainstream photovoltaic cell technology.

[0003] The electrodes of BC batteries are located in the N-region and P-region on the back of the cell. However, the N-region, P-region, and the gap region within them have inconsistent heights, resulting in height differences. Current methods for manufacturing these electrodes involve screen printing. Electroformed metal screens offer advantages over polyimide (PI) screens in terms of printing morphology, lifespan, and manufacturing cost, and are widely used in grid line printing for existing battery cells. Electroformed metal screens typically have fully open patterns. When printing patterns with height differences, the openings of the metal screen pattern deform due to metal fatigue, leading to thicker lines. Furthermore, due to differences in metal resilience, if the openings are obstructed by foreign objects during the printing process, the screen may deform prematurely and fail to print. Therefore, this invention proposes a high-lifespan screen for printing BC batteries and its manufacturing process. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a high-lifespan screen printing plate for BC batteries and its preparation process.

[0005] To solve the above-mentioned technical problems, the present invention achieves its objective as follows: The present invention relates to a high-lifespan screen printing plate for BC batteries, comprising a metal substrate, a polymer film layer disposed on at least one end face of the metal substrate, a flexible buffer layer disposed between the polymer film layer and the metal substrate, and a patterned area processed on the polymer film layer.

[0006] The present invention is further configured such that: the surface of the metal substrate is subjected to pulse anodizing treatment to generate a porous oxide layer.

[0007] The present invention is further configured such that the polymer film layer is one or more of polyimide, epoxy resin, parylene and its derivatives.

[0008] The present invention is further configured such that the flexible buffer layer is a siloxane polymer layer.

[0009] The present invention is further configured such that the metal substrate is a nickel substrate.

[0010] This invention also relates to a process for preparing the high-lifespan screen, comprising the above steps: S1. Perform pulse anodizing on the nickel substrate to generate a porous oxide layer with a pore size of 200-500 nm and a porosity controlled at 30%-40%; S2. A flexible buffer layer of siloxane polymer with a thickness of 50-100 nm is constructed by vapor deposition technology. The flexible buffer layer forms a modulus gradient transition region through molecular self-assembly. S3. Prepare a polymer film layer; the polymer film layer includes at least one of the following: a polyimide layer formed by hot pressing transfer, an epoxy resin layer formed by spraying, and a parylene layer formed by PECVD coating. S4. Use laser engraving to pattern the polymer film layer, maintaining consistent alignment with the pattern on the base metal electroforming screen.

[0011] The present invention is further configured such that the precursor for preparing the siloxane polymer flexible buffer layer is selected from one or more of methyltrimethoxysilane, siloxane derivatives, and polyurethane-siloxane copolymers.

[0012] The present invention is further configured such that the thickness of the polymer film layer is 1-10 μm.

[0013] The present invention is further configured such that: if the polymer film layer is a polyimide layer, a two-stage temperature control process is adopted to enable the film material to complete interface fusion during the plastic deformation stage.

[0014] The present invention is further configured such that the two-stage temperature control specifically includes: a first stage of maintaining temperature and pressure at 120℃ and 0.5MPa for 60s to soften the polyimide film; and a second stage of maintaining temperature and pressure at 180℃ and 1.2MPa for 90s to complete the curing and shaping of the film.

[0015] In summary, the present invention has the following beneficial effects: 1. The gradient buffer layer design reduces interfacial stress by more than 60%, preventing deformation or detachment of the polymer layer from the base metal electroforming screen.

[0016] 2. The porous structure greatly enhances the bonding strength.

[0017] 3. The designed composite film layer screen printing plate has a good buffering effect during printing, and its lifespan is increased by more than 50%. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions of the present invention, preferred embodiments of the present invention are described below in conjunction with specific examples. However, it should be understood that these descriptions are merely for further illustrating the features and advantages of the present invention, and not for limiting the scope of the patent claims of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0019] The present invention will be further described below with reference to preferred embodiments.

[0020] Example 1 The high-lifespan screen printing plate for BC batteries involved in this embodiment includes a metal substrate, at least one end face of the metal substrate is provided with a polymer film layer, a flexible buffer layer is provided between the polymer film layer and the metal substrate, and a patterned area is processed on the polymer film layer.

[0021] Furthermore, a porous oxide layer is generated on the surface of the metal substrate through pulsed anodizing treatment.

[0022] Furthermore, the polymer film layer is made of one or more of polyimide, epoxy resin, parylene and its derivatives.

[0023] Furthermore, the flexible buffer layer is a siloxane polymer layer.

[0024] Furthermore, the metal substrate is a nickel substrate.

[0025] It also involves the preparation process of this high-lifespan screen, including the above steps: S1. Perform pulse anodizing treatment on the nickel substrate (0.3-0.7 A / dm). 2 This process generates a porous oxide layer with a pore size of 200-500 nm and a porosity controlled at 30%-40%, which significantly increases the effective contact area and can improve the adhesion of subsequent polymer films. S2. A flexible buffer layer of siloxane polymer with a thickness of 50-100 nm is constructed by vapor deposition. The flexible buffer layer forms a modulus gradient transition region (2GPa→70GPa) through molecular self-assembly, which disperses the stress brought about by subsequent hot pressing, spraying and other processes to prepare polymer thin film layers. S3. Prepare a polymer film layer; the polymer film layer includes at least one of the following: a polyimide layer formed by hot pressing transfer, an epoxy resin layer formed by spraying, and a parylene layer formed by PECVD coating. S4. Use laser engraving to pattern the polymer film layer, maintaining consistent alignment with the pattern on the base metal electroforming screen.

[0026] Furthermore, in step S2, the precursor for preparing the siloxane polymer flexible buffer layer is selected from one or more of methyltrimethoxysilane, siloxane derivatives, and polyurethane-siloxane copolymers.

[0027] Furthermore, in step S3, the thickness of the polymer film layer is 1-10 μm.

[0028] Furthermore, in step S3, if the polymer film layer is a polyimide layer, a two-stage temperature control process is adopted to enable the film material to complete interface fusion during the plastic deformation stage.

[0029] Furthermore, the two-stage temperature control specifically includes: the first stage of maintaining the temperature and pressure at 120℃ and 0.5MPa for 60s to soften the polyimide film; and the second stage of maintaining the temperature and pressure at 180℃ and 1.2MPa for 90s to complete the curing and shaping of the film.

[0030] In this embodiment, by making the metal electroforming stencil into a multi-layer composite material, its fatigue resistance, local deformation resistance, and resilience under deformation are enhanced. Polymer materials generally have more easily controllable mechanical properties than metallic materials, offering greater flexibility in terms of strength, plasticity, toughness, and hardness.

[0031] The high-lifespan screen printing plate for BC batteries and its preparation process involved in this invention reduce interfacial stress by more than 60% through a gradient buffer layer design, preventing deformation or detachment of the polymer layer from the substrate metal electroformed screen. The porous structure significantly enhances the bonding strength. Furthermore, the designed composite film layer screen provides excellent buffering during printing, increasing lifespan by more than 50%. Overall, it boasts comprehensive functionality and strong practicality.

[0032] Unless otherwise specified, in this invention, terms such as "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the actual orientation or positional relationship shown. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe orientation or positional relationships in this invention are for illustrative purposes only and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood in conjunction with the embodiments and according to the specific circumstances.

[0033] Unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" in this invention should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0034] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A high-lifespan screen printing plate for BC batteries, comprising a metal substrate, characterized in that, At least one end face of the metal substrate is provided with a polymer film layer, a flexible buffer layer is provided between the polymer film layer and the metal substrate, and a patterned area is processed on the polymer film layer.

2. The high-lifespan screen printing plate for BC batteries according to claim 1, characterized in that, The surface of the metal substrate is subjected to pulsed anodizing to generate a porous oxide layer.

3. The high-lifespan screen printing plate for BC batteries according to claim 2, characterized in that, The polymer film layer is made of one or more of polyimide, epoxy resin, parylene and its derivatives.

4. The high-lifespan screen printing plate for BC batteries according to claim 3, characterized in that, The flexible buffer layer is a siloxane polymer layer.

5. The high-lifespan screen printing plate for BC batteries according to claim 4, characterized in that, The metal substrate is a nickel substrate.

6. A process for preparing a high-lifespan screen printing plate according to claim 5, characterized in that, Including the above steps: S1. Perform pulse anodizing on the nickel substrate to generate a porous oxide layer with a pore size of 200-500 nm and a porosity controlled at 30%-40%; S2. A flexible buffer layer of siloxane polymer with a thickness of 50-100 nm is constructed by vapor deposition technology. The flexible buffer layer forms a modulus gradient transition region through molecular self-assembly. S3. Prepare a polymer film layer; the polymer film layer includes at least one of the following: a polyimide layer formed by hot pressing, an epoxy resin layer formed by spraying, and a parylene layer formed by PECVD coating. S4. Use laser engraving to pattern the polymer film layer, maintaining consistent alignment with the pattern on the base metal electroforming screen.

7. The preparation process of the high-lifespan screen printing plate according to claim 6, characterized in that, In step S2, the precursor for preparing the siloxane polymer flexible buffer layer is selected from one or more of methyltrimethoxysilane, siloxane derivatives, and polyurethane-siloxane copolymers.

8. The preparation process of the high-lifespan screen printing plate according to claim 6, characterized in that, In step S3, the thickness of the polymer film layer is 1-10 μm.

9. The preparation process of the high-lifespan screen printing plate according to claim 6, characterized in that, In step S3, if the polymer film layer is a polyimide layer, a two-stage temperature control process is adopted to enable the film material to complete interface fusion during the plastic deformation stage.

10. The manufacturing process of the high-lifespan screen printing plate according to claim 9, characterized in that, The two-stage temperature control specifically includes: the first stage is to maintain the temperature and pressure at 120℃ and 0.5MPa for 60s to soften the polyimide film; the second stage is to maintain the temperature and pressure at 180℃ and 1.2MPa for 90s to complete the curing and shaping of the film.