A transfer system for photovoltaic cells

Abstract

The application provides a transfer printing system for a photovoltaic cell, which comprises a feeding system, a slurry grinding system and a non-contact printing system. The feeding system comprises a feeding box, a guide rail and a support box. The cell piece is turned from a horizontal position to a vertical state and is input into the printing system. The slurry grinding system comprises three units. Each unit comprises a feeding device, a grinding device and a feeding device. The slurry is added into the feeding device, is guided into the grinding device by the feeding device and is output from the grinding device to a storage device of the non-contact printing system to become printing slurry. The non-contact printing system comprises three units. Each unit comprises a substrate, a laser printing device and a storage device. The slurry is transmitted from the slurry grinding system to the storage device in the printing system. The laser printing device is provided with a transfer substrate. The laser printing device transfers the printing slurry to the cell piece through the transfer substrate. The application realizes the simultaneous printing of the front and back surfaces of the cell piece and reduces the process links.

Description

Technical Field

[0001] The present invention relates to the application field of photovoltaic components, and in particular to a transfer system and a transfer method for photovoltaic cells. Background Art

[0002] The manufacturing process for traditional crystalline silicon photovoltaic cells involves texturing, diffusion, etching and cleaning, passivation, coating, and printing. The printing process is crucial for photovoltaic cell manufacturing. This process involves back-silver printing, drying, back-aluminum printing, drying, flipping, and then front-side printing. Some front-side printing is performed in stages, followed by sintering and testing. The printing process alone involves four printing steps and three drying stages. Each stage requires personnel to operate. Furthermore, the printing process requires regular replacement of screens and slurries, and these complex operations impact the production line.

[0003] Traditional photovoltaic cell printing is done using screen printing. Limited by the mesh and process limitations of the screen, the current printed line width is limited to around 20µm, creating a bottleneck in reducing silver paste consumption. Furthermore, wider electrode widths increase the shading area, thus affecting the cell's conversion efficiency. Summary of the Invention

[0004] In order to solve the problems of the prior art, the present invention provides a new transfer technology for photovoltaic cells. On the one hand, it reduces the existing printing steps, and on the other hand, through the new transfer technology, it reduces the printing line width, reduces the consumption of silver paste, and improves the battery conversion efficiency.

[0005] The present invention provides a transfer system for photovoltaic cells, comprising a loading system, a slurry grinding system, and a contactless printing system. The loading system comprises a loading box, a guide rail, and a support box. The cell is flipped from a horizontal position to a vertical position and fed into the printing system.

[0006] The slurry grinding system includes three units, each unit includes a feeding device, a grinding device, and a feeding device. The slurry is added to the feeding device and introduced into the grinding device by the feeding device. The output end of the grinding device is connected to the storage device of the contactless printing system to become the printing slurry;

[0007] The contactless printing system includes three units, each of which includes a substrate, a laser printing device, and a storage device. The slurry is transferred from the slurry grinding system to the storage device in the printing system. A transfer substrate is provided in the laser printing device, and the laser printing device transfers the printed slurry to the battery cell through the transfer substrate.

[0008] The transfer system includes three modules: back silver, back aluminum, and front silver. Correspondingly, each module also includes three contactless printing units and three slurry grinding units.

[0009] Furthermore, the contactless printing system further includes a camera, which is installed at the connection position between the loading system and the contactless printing system and is used to identify the position of the battery cell.

[0010] Furthermore, each grinding device is provided with three rollers installed side by side to grind the slurry, and the slurry is transferred to the storage device of the contactless printing system through a pipeline.

[0011] Furthermore, the slurry grinding system is also provided with a gripper bracket, which is placed next to the grinding device and is used to lift the container containing the slurry to the feed inlet position of the grinding device.

[0012] Furthermore, the slurry grinding system is further provided with a circulation device, wherein the circulation device connects the outlet of the grinding device to the feeding device through a pipeline to achieve repeated grinding of the slurry.

[0013] Furthermore, the back silver and front silver polishing units are respectively connected to a contactless printing unit, and the two sets of polishing units and printing systems are placed in a mirror image, and the printing ends of the two printing systems are arranged opposite to each other, so as to realize printing on both sides of a battery cell at the same time.

[0014] The beneficial effects of the present invention are:

[0015] Existing coating technologies involve atomic deposition under vacuum conditions, with nanometer-level depths. This process occurs directly within a vacuum chamber, without passing through a substrate. In the present invention, a roller first applies slurry to a transfer substrate with a pattern. The thickness of the transfer substrate ensures the slurry can be shaped properly. A laser is then used to print the slurry from the pores of the pattern onto the cell.

[0016] This invention utilizes a novel transfer printing technology in the photovoltaic cell electrode printing method to achieve simultaneous printing on both the front and back sides of the cell, significantly reducing the number of existing process steps. By replacing the traditional scraper printing method with a grinding system, the slurry particles are uniform and agglomerated. Furthermore, by essentially replacing traditional screen printing with laser printing technology, a barrier-free printing width is achieved, resulting in finer grid lines, reduced shading area, increased efficiency, and reduced slurry usage. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments:

[0018] Figure 1 Printing flow chart for traditional photovoltaic cells;

[0019] Figure 2 The photovoltaic cell printing flow chart provided by the present invention;

[0020] Figure 3 A schematic diagram of a transfer system for photovoltaic cells provided by the present invention;

[0021] Figure 4 The feeding system provided by the present invention;

[0022] Figure 5 The slurry grinding system provided by the present invention;

[0023] Figure 6 The contactless printing system provided by the present invention;

[0024] In the figure, 1-empty bracket; 2-battery cell; 3-loading box; 4-bracket box with battery cells; 5-inverted bracket box; 6-gripper bracket; 7-barrel; 8-grinder; 9-grinder switch; 10-roller; 11-conveyor belt; 12-printing system; 13-transfer substrate with hollow pattern; 14-printing roller; 15-laser system. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] Example 1

[0027] The present invention provides a transfer system for photovoltaic cells, comprising a loading system, a slurry grinding system, and a contactless printing system. The loading system comprises a loading box, a guide rail, and a support box. The cell is flipped from a horizontal position to a vertical position and fed into the printing system.

[0028] The slurry grinding system includes three units, each unit includes a feeding device, a grinding device, and a feeding device. The slurry is added to the feeding device and introduced into the grinding device by the feeding device. The output end of the grinding device is connected to the storage device of the contactless printing system to become the printing slurry;

[0029] The contactless printing system includes three units, each of which includes a substrate, a laser printing device, and a storage device. The slurry is transferred from the slurry grinding system to the storage device in the printing system. A transfer substrate is provided in the laser printing device, and the laser printing device transfers the printed slurry to the battery cell through the transfer substrate.

[0030] The transfer system includes three modules: back silver, back aluminum, and front silver. Correspondingly, each module also includes three contactless printing units and three slurry grinding units.

[0031] The battery cells flow out of the loading box and enter the bracket box. After the bracket box is loaded with battery cells, it flows in the guide rail. At the end of the loading system, the bracket box is turned over and becomes vertical.

[0032] Furthermore, the contactless printing system further includes a camera, which is installed at the connection position between the loading system and the contactless printing system and is used to identify the position of the battery cell.

[0033] Furthermore, each grinding device is provided with three rollers installed side by side to grind the slurry, and the slurry is transferred to the storage device of the contactless printing system through a pipeline.

[0034] Furthermore, the slurry grinding system is also provided with a gripper bracket, which is placed next to the grinding device and is used to lift the container containing the slurry to the feed inlet position of the grinding device.

[0035] Furthermore, the slurry grinding system is further provided with a circulation device, wherein the circulation device connects the outlet of the grinding device to the feeding device through a pipeline to achieve repeated grinding of the slurry.

[0036] As a preferred embodiment of the present application, the back silver and front silver polishing units are respectively connected to the contactless printing system, and the two sets of polishing units and printing systems are placed in a mirror image, and the printing ends of the two printing systems are arranged opposite to each other, so as to realize simultaneous printing on the front and back sides of a battery cell.

[0037] like Figure 1 As shown in FIG, the traditional photovoltaic cell printing process is mainly divided into back silver printing, drying, back aluminum printing, drying, front silver printing, drying and other links. The new transfer technology used in the present invention is divided into new transfer technology, drying, such as Figure 2 This technology can achieve simultaneous printing on both sides and only requires one drying step.

[0038] Figure 3This is a new transfer technology system of the present invention. It is mainly divided into three parts: the feeding system, the grinding system, and the printing system. The battery cells are transferred from the feeding system. The back silver paste passes through the grinding system 1 to make its particle size finer and prevent agglomeration. Then it enters the printing system 1, and is squeezed into the hollow pattern of the transfer substrate by rollers. The back silver paste is sprayed onto the back of the battery cell by laser to complete the electrode printing process. The back aluminum paste and the front silver paste go through the same operating steps as the back silver, and pass through the grinding system 2-printing system 2 and the grinding system 3-printing system 3 respectively. Back aluminum printing and front silver printing can be completed simultaneously.

[0039] Figure 4 In the loading system of the present invention, an empty rack 1 moves along a guide rail, and cells 2 are loaded from a loading cassette 3 into the rack within the guide rail. The cassette loads the cells and secures them during movement, as shown in Figure 4. When the cassette reaches one end, it flips from a horizontal position to a vertical position, as shown in Figure 5.

[0040] Figure 5 The grinding system of the present invention consists of a gripper bracket 6 that picks up a drum 7 containing slurry and pours it into a grinder 8. The grinder 8 is operated by a switch 9 on the side, and the roller 10 of the grinder grinds the slurry. During grinding, the grinding system can be activated and repeated. Compared with the original printing press method of scraping slurry, this solution makes the slurry particle size more uniform and prevents agglomeration. The grinding system is combined with the printing system. In the entire transfer system, there are three grinding systems: back silver, back aluminum, and front silver.

[0041] Figure 6 The printing system of the present invention uses a conveyor belt 11 in the grinding system to transfer the ground slurry to the printing system 12. At the other end, a transfer substrate 13 with a hollowed-out pattern circulates forward. This technology replaces the existing silk screen screen and enables narrower line width designs. The slurry is squeezed into the transfer substrate 13 with a hollowed-out pattern by a roller 14 at one end. The extruded transfer substrate moves forward. When the slurry-laden substrate overlaps the battery cell 5, which has been flipped vertically in the loading system, a camera in the laser system 15 in the printing system positions it and emits a laser, spraying the slurry in the holes of the substrate 13 onto the battery cell 5, completing the non-contact printing. This new transfer technology system has three printing systems, one for back silver, one for back aluminum, and one for front silver. Both sides of the battery cell can be printed simultaneously. Because the battery cell remains in a vertical, non-contact position during movement, the entire printing process is complete, allowing for normal drying and sintering.

[0042] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed by the present invention and do not depart from the principles of the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A transfer system for photovoltaic cells, characterized in that: The transfer system includes a loading system, a slurry grinding system, and a contactless printing system. The loading system includes a loading box, a guide rail, and a support box. The battery cells flow out of the loading box and enter the support box. After the support box is loaded with battery cells, it flows in the guide rail. At the end of the loading system, the support box is turned over, and the battery cells are in a vertical state and input into the contactless printing system. The slurry grinding system includes three slurry grinding units, each of which includes a feeding device, a grinding device, and a feeding device. The slurry is added to the feeding device and introduced into the grinding device by the feeding device. The output end of the grinding device is connected to the storage device of the contactless printing system as printing slurry; The non-contact printing system includes three non-contact printing units, each of which includes a transfer substrate, a laser printing device, and a storage device. The slurry is transferred from the slurry grinding system to the storage device in the non-contact printing system. The laser printing device is provided with a transfer substrate, and the laser printing device transfers the printed slurry to the battery cell through the transfer substrate. The transfer system includes three modules: back silver, back aluminum, and front silver. Correspondingly, each module includes a contactless printing unit and a slurry grinding unit; the slurry grinding units of the back silver module and the front silver module are respectively connected to one of the contactless printing units, and the slurry grinding unit and contactless printing unit of the back silver module are placed in a mirror image with the slurry grinding unit and contactless printing unit of the front silver module. The printing ends of the contactless printing unit of the back silver module and the contactless printing unit of the front silver module are arranged opposite to each other, so as to realize simultaneous printing on the front and back sides of a battery cell; The slurry grinding system transfers the ground slurry to the contactless printing system. The other end of the contactless printing system is circulated forward by a transfer substrate with a hollow pattern. The slurry is squeezed into the transfer substrate with the hollow pattern by the roller at one end of the contactless printing system. The transfer substrate that has completed the extrusion moves forward. When the transfer substrate with the slurry coincides with the battery cell that has been flipped into a vertical state in the feeding system, the laser printing device in the contactless printing system emits a laser to spray the slurry in the holes of the transfer substrate onto the battery cell to complete the non-contact printing.

2. A transfer system for photovoltaic cells according to claim 1, characterized in that: The contactless printing system further comprises a camera, which is installed at the connection position between the loading system and the contactless printing system and is used to identify the position of the battery cell.

3. A transfer system for photovoltaic cells according to claim 1, characterized in that: Each grinding device is equipped with three rollers installed side by side to grind the slurry, and the slurry is transferred to the storage device of the contactless printing system through a pipeline.

4. The transfer system for photovoltaic cells according to claim 1, characterized in that: The slurry grinding system is further provided with a gripping bracket, which is placed beside the grinding device and is used to lift the container containing the slurry to the feed inlet position of the grinding device.

5. The transfer system for photovoltaic cells according to claim 3, characterized in that: The slurry grinding system is further provided with a circulation device, which connects the outlet of the grinding device to the feeding device through a pipeline to achieve repeated grinding of the slurry.

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