Solar cell and preparation method thereof, photovoltaic module

Abstract

This application discloses a solar cell and its fabrication method, as well as a photovoltaic module. The solar cell includes a cell body and a coloring layer. The cell body has a light-receiving surface and a backlighting surface arranged opposite to each other. The light-receiving surface includes a central region and an edge region surrounding the central region, with a color difference area formed in the edge region. The coloring layer is disposed in the edge region and at least partially covers the color difference area. Using the solar cell structure of this application, the color difference problem on the light-receiving surface of the cell body can be effectively reduced, and damage to the edges of the cell body can be avoided. Furthermore, by providing a coloring layer at the edges of the cell body, the edges of the cell body can be passivated and leakage protection can be provided, thereby improving the performance of the solar cell.

Description

[0001] This application claims priority to Chinese patent applications filed on May 23, 2025, with application number 2025106794968, entitled "A Solar Cell and its Preparation Method, and a Photovoltaic Module", and filed on September 22, 2025, with application number 2025113575804, entitled "A Solar Cell and its Preparation Method, and a Photovoltaic Module", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application belongs to the field of photovoltaic technology, specifically relating to a solar cell and its preparation method, and a photovoltaic module. Background Technology

[0003] A solar cell is a semiconductor optoelectronic device that can convert sunlight into electrical energy. In the manufacturing process of solar cells, it is usually necessary to deposit a dielectric layer or a doped semiconductor layer on the back of the cell. Currently, the deposition coating method is mainly used to prepare the coating layer. During the coating process, it is inevitable that a coating or a dot mark will be formed on the edge area of ​​the front of the cell, resulting in a color difference between the edge area and the middle area of ​​the cell, that is, there is a color difference area at the edge of the cell.

[0004] In related technologies, wet etching is typically used to remove the coating or markings on the front side of the solar cell in order to eliminate color difference areas. However, wet etching can easily damage the edges of the solar cell, reducing its conversion efficiency. Summary of the Invention

[0005] This application aims to provide a solar cell and its preparation method, as well as a photovoltaic module, which can solve the problem in related technologies that the wet process for removing color difference areas at the edge of the solar cell can easily damage the edge of the solar cell and reduce the conversion efficiency of the solar cell.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows: In a first aspect, embodiments of this application disclose a solar cell, comprising: The battery body has a light-receiving surface and a backlighting surface arranged opposite to each other. The light-receiving surface includes a central region and an edge region arranged around the central region. A color difference area is formed in the edge region. A coloring layer is disposed in the edge region and at least partially covers the color difference region.

[0007] Secondly, embodiments of this application provide a method for preparing a solar cell, used to prepare the solar cell described in the first aspect, comprising: Identify the light-receiving surface of the battery body and fit the actual contour shape of the battery body; The side position of the light-receiving surface is determined based on the actual contour shape; The coloring region corresponding to the side is determined based on the side position; A coloring layer is formed within the coloring area, such that the coloring layer at least partially covers the color difference area at the edge of the light-receiving surface.

[0008] Thirdly, embodiments of this application provide a photovoltaic module, the photovoltaic module comprising multiple battery strings, each battery string comprising multiple solar cells and multiple interconnecting elements, the interconnecting elements being used to connect the multiple solar cells in series; wherein, the solar cells are the solar cells described in any one of the first aspects.

[0009] In this application, a coloring layer is provided around the perimeter of the battery body, and this coloring layer at least partially covers the color difference areas present in the edge regions, thereby reducing the color difference on the light-receiving surface of the battery body. Using the solar cell structure of this application, the color difference problem on the light-receiving surface of the battery body can be effectively reduced, and damage to the edges of the battery body can be avoided. Furthermore, by providing a coloring layer at the edges of the battery body, the edges can also be passivated and leakage protected, thereby improving the performance of the solar cell.

[0010] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments will be briefly introduced below, wherein: Figure 1 This is a schematic diagram of a solar cell according to an embodiment of this application; Figure 2 This is a side sectional view of a first type of solar cell according to an embodiment of this application; Figure 3 This is a top view of a first type of solar cell according to an embodiment of this application; Figure 4 This is a side sectional view of a second type of solar cell according to an embodiment of this application; Figure 5 This is a schematic diagram of the coating area on the light-receiving surface of the battery body according to an embodiment of this application; Figure 6This is a schematic diagram of the dot print on the light-receiving surface of the battery body according to an embodiment of this application; Figure 7 This is a side sectional view of a third type of solar cell according to an embodiment of this application; Figure 8 This is a top view of a third type of solar cell according to an embodiment of this application; Figure 9 This is a side sectional view of a fourth type of solar cell according to an embodiment of this application; Figure 10 This is a side sectional view of a fifth type of solar cell according to an embodiment of this application; Figure 11 This is a side sectional view of a sixth type of solar cell according to an embodiment of this application; Figure 12 This is a side sectional view of a seventh type of solar cell according to an embodiment of this application; Figure 13 This is a side sectional view of an eighth type of solar cell according to an embodiment of this application; Figure 14 This is a schematic diagram illustrating the identification principle of a solar cell according to an embodiment of this application; Figure 15 This is a schematic diagram of the colored area corresponding to the side of the solar cell according to an embodiment of this application; Figure 16 This is a schematic diagram of the colored area corresponding to the side of a solar cell, as identified and determined by existing technology. Figure 17 This is a schematic diagram of the fabrication process of a solar cell according to an embodiment of this application; Figure 18 This is a side sectional view of a ninth type of solar cell according to an embodiment of this application; Figure 19 This is a side sectional view of a tenth type of solar cell according to an embodiment of this application; Figure 20 This is a SEM image of the corresponding edge portion of the solar cell according to an embodiment of this application; Figure 21 This is a schematic diagram of the organic diffusion structure on the light-receiving surface of a solar cell according to an embodiment of this application; Figure 22 This is an LBIC test diagram of a solar cell in which the coloring layer does not completely cover the color difference area according to an embodiment of this application; Figure 23 This is an LBIC test diagram of a solar cell in which the coloring layer completely covers the color difference area according to an embodiment of this application; Figure 24 This is a schematic diagram of the coloring layer structure at the corresponding card-printed area on the light-receiving surface of the solar cell according to an embodiment of this application; Figure 25This is a schematic diagram showing the discontinuous arrangement of the color layer in the color difference area on the light-receiving surface of a solar cell according to an embodiment of this application. Figure 26 This is a schematic diagram of the film structure of the solar cell corresponding to the N-region and P-region according to an embodiment of this application; Figure 27 This is a side sectional view of the corresponding edge portion of the eleventh type of solar cell according to an embodiment of this application; Figure 28 This is a SEM image of the coloring layer according to an embodiment of this application; Figure 29 This is an EDS diagram of the coloring layer according to an embodiment of this application; Figure 30 This is a schematic diagram of the first movement trajectory of a printhead according to an embodiment of this application; Figure 31 This is a schematic diagram of a second type of movement trajectory of a printhead according to an embodiment of this application; Figure 32 This is a schematic diagram of a third movement trajectory of a printhead according to an embodiment of this application.

[0012] Figure label: 10: Battery body; 100: Semiconductor substrate; 120: Film structure; 121a: Tunneling oxide layer; 122a: N-type doped layer; 121b: P-type doped layer; 122b: Intrinsic amorphous silicon layer; 124: Passivation layer; 125: Antireflection layer; 11: Light-receiving surface; 101: Textured surface; 12: Backlight surface; 1021: N 1022: P-type collection area; 1023: Isolation opening; 13: Side surface; 11a: Middle area; 11b: Edge area; 110: Color difference area; 111: Wrap-around plating area; 112: Marking; 14: Side edge; 140: Colored area; 20: Colored layer; 20a: First colored part; 20b: Second colored part; 21: First colored layer; 22: Second colored layer; 221: Hollow structure; 202: Carbon agglomerate; 30: Isolation protrusion; 40: Base layer; A1: First point; A2: Second point; A3: Third point; A4: Fourth point; θ1: First included angle; θ2: Second included angle; 15: Chamfered surface; 16: Transition slope. Detailed Implementation

[0013] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0014] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0015] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0016] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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 mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0017] Solar cells have a light-receiving surface that receives sunlight and a back-lighting surface that faces away from it. During the cell fabrication process, a dielectric layer or a doped semiconductor layer is formed on the back-lighting surface. Common coating techniques include tubular CVD (Chemical Vapor Deposition), plate CVD, or PVD (Physical Vapor Deposition). A graphite boat is typically used as a support device to hold the cell horizontally or vertically within the boat before it enters the coating chamber. During coating, some reactive gases migrate to the edge region of the light-receiving surface (also known as the front side) and react to form a wrap-around coating. The color of this wrap-around coating differs from the color of other areas of the light-receiving surface, resulting in a color difference between the edge and center regions of the final solar cell. Furthermore, the light-receiving surface often requires a passivation anti-reflection layer to increase light absorption. During coating, the film thickness at the edges often differs from that in the center, leading to a color difference between the two regions. Secondly, the multiple wet processes involved in cell fabrication, such as polishing or texturing, can cause differences in the morphology of the edge areas of the light-receiving surface compared to other areas. For example, uneven texturing at the edges of the light-receiving surface, while uniform texturing in the middle, results in different reflectivities between the edges and the middle, leading to color differences between the two areas. Furthermore, when using a graphite boat to support the cells for front-side coating, the boat has locking points to fix the edges of the cells. Due to the obstruction of these locking points, imprints are formed on the front of the cells at the corresponding locations. The color of the light-receiving surface at these imprints will also differ from the color of other areas. These color differences at the edges of the cells directly affect the aesthetics of the solar cell products.

[0018] In related technologies, to address the edge color difference problem on the light-receiving surface of solar cells, one approach is to adjust the coating process to improve the color difference. However, this method has limited effectiveness in improving the color difference and can also affect the coating quality on the cell surface. Another approach is to remove the color difference at the cell edges through wet etching after cell fabrication. While this method can eliminate the color difference, it is complex and can easily damage the cell edges during etching, reducing the cell's conversion efficiency.

[0019] Therefore, this application provides a solar cell and its fabrication method to solve the color difference problem of the light-receiving surface of solar cells in the prior art without affecting the conversion efficiency of the cell. The solar cell, its fabrication method, and photovoltaic module provided in this application will be described in detail below with reference to the accompanying drawings and specific embodiments and application scenarios.

[0020] like Figures 1 to 4 As shown, a solar cell according to some embodiments of this application includes: a cell body 10 and a coloring layer 20. The cell body 10 has a light-receiving surface 11 and a backlighting surface 12 disposed opposite to each other. The light-receiving surface 11 includes a central region 11a and an edge region 11b disposed around the central region 11a. A color difference region 110 is formed in the edge region 11b. The coloring layer 20 is disposed in the edge region 11b and at least partially covers the color difference region 110.

[0021] In this embodiment, a coloring layer 20 is provided on the periphery 11b of the battery body 10, and the coloring layer 20 at least partially covers the color difference area 110 present in the edge area 11b, thereby reducing the color difference of the light-receiving surface 11 of the battery body 10. Using the solar cell structure of this application, the color difference problem of the light-receiving surface 11 of the battery body 10 can be effectively reduced, and damage to the edge of the battery body 10 can be avoided. Furthermore, by providing the coloring layer 20 on the edge of the battery body 10, the edge of the battery body 10 can also be passivated and leakage protected, thereby improving the performance of the solar cell.

[0022] It should be noted that, in the accompanying drawings of this application, the coloring layer 20 is shown to be formed on the edge region 11b of the light-receiving surface 11, and the filling color of the coloring layer 20 is distinguished from the color of the middle region 11a of the light-receiving surface 11. However, in actual solar cell products, the color of the coloring layer 20 is the same as or similar to the color of the middle region 11a of the light-receiving surface 11 in order to eliminate the color difference of the light-receiving surface 11.

[0023] In some embodiments, the coloring layer 20 may be made of a non-transparent insulating material, such as ink. The coloring layer 20 can be formed in the edge region 11b of the battery body 10 by means of printing, 3D printing, or spraying, so as to cover the color difference area 110 within the edge region 11b, thereby reducing or even eliminating the color difference present on the light-receiving surface 11 of the battery body 10. The coloring layer 20 has a specific color, which can be set to match the color of the middle region 11a of the light-receiving surface 11 of the battery body 10. The specific color setting of the coloring layer 20 can be determined according to the actual color of the light-receiving surface 11 of the battery body 10, and the preparation method of the coloring layer 20 can be flexibly selected and is not limited here.

[0024] It should be noted that the coverage area and placement of the coloring layer 20 on the edge region 11b of the battery body 10 can be flexibly set according to the size and position of the color difference area 110 on the edge region 11b of the light-receiving surface 11, and are not limited here. It is understood that the light-receiving surface 11 of the battery body 10 has four sides, and a color difference area 110 may be formed on the edge corresponding to each side. The coloring layer 20 can be arranged around the circumference of the light-receiving surface 11, and the coloring layer 20 can be continuously arranged around the circumference of the light-receiving surface 11, or it can be intermittently arranged around the light-receiving surface 11, as long as it can eliminate the color difference of the light-receiving surface 11. Furthermore, on the light-receiving surface 11, the width of the coloring layer 20 at different positions corresponding to the same side can be the same or different, and the width of the coloring layer 20 at different sides can be the same or different. In practical applications, it can be flexibly set according to the actual position and size of the color difference area 110 on the four edges of the light-receiving surface 11, and is not limited here.

[0025] In some embodiments, such as Figure 5 As shown, the color difference area 110 includes a plating area 111 formed in the edge region 11b; as Figure 3 As shown, the coloring layer 20 includes a first coloring layer 21, which surrounds the central region 11a and partially or completely covers the surrounding plating area 111. It should be noted that the light-receiving surface 11 of the battery body 10 has a quadrilateral structure with four sides. A surrounding plating area 111 may be formed on the edge corresponding to each side. The width of the surrounding plating area 111 corresponding to the same side may differ at different locations. Furthermore, the width of the surrounding plating area 111 corresponding to different sides may also differ. Therefore, in practical applications, the coloring layer can be flexibly set according to the actual position and width of the surrounding plating area 111 on the four edges of the light-receiving surface 11, without any limitations here.

[0026] In the fabrication process of solar cells, when coating the back surface 12 of the cell body 10, a coating layer inevitably forms around the edges of the light-receiving surface 11. This results in a color difference between the area of ​​the light-receiving surface 11 with the coating layer and other areas of the light-receiving surface 11. This area of ​​the light-receiving surface 11 with the coating layer is designated as the coating area 111. Furthermore, by forming an annular first coloring layer 21 in the edge region 11b of the light-receiving surface 11, the coating area 111 is covered by the first coloring layer 21 to reduce the color difference between the coating area 111 and other areas of the light-receiving surface 11. The coating layer includes, but is not limited to, passivation and antireflection layers, tunneling oxygen, and doped polycrystalline silicon layers stacked in the direction away from the light-receiving surface. These layers can be flexibly configured according to actual needs and are not limited here.

[0027] It is understandable that the annular first coloring layer 21 located around the edge of the light-receiving surface 11 can be continuously or intermittently arranged. The first coloring layer 21 can completely cover the surrounding plating area 111 to eliminate color difference caused by the surrounding plating layer; or the first coloring layer 21 can partially cover the surrounding plating area 111, that is, a portion of the surrounding plating layer is exposed on the edge of the battery body 10.

[0028] For example, such as Figure 2 and Figure 4 As shown, the portion of the coating around the periphery of the light-receiving surface 11 of the battery body 10 is not covered by the coloring layer 20. That is, there is a certain gap between the first coloring layer 21 and the side 14 of the adjacent light-receiving surface 11.

[0029] It is understandable that, due to the presence of the coating, although a color difference may occur on the light-receiving surface 11, the coating also serves to passivate the edges of the battery body 10 and protect against leakage. Therefore, in this application, by setting a first coloring layer 21 in the edge region 11b, the first coloring layer 21 partially covers the coating, leaving the edge portion of the coating exposed. In this way, the performance of the solar cell is not affected, the color difference on the light-receiving surface 11 is reduced, and the cost of manufacturing the first coloring layer 21 is also reduced.

[0030] In other embodiments, such as Figure 6 As shown, the color difference area 110 includes a plurality of dot imprints 112 formed in the edge area 11b, and the plurality of dot imprints 112 are arranged at intervals around the perimeter of the central area 11a; as Figure 3 As shown, the coloring layer 20 includes a second coloring layer 22, which partially or completely covers the card dot print 112.

[0031] In the fabrication process of solar cells, when coating the light-receiving surface 11 of the cell body 10, due to the influence of the dot structure in the graphite boat, dot marks 112 will be formed in the surrounding edge area 11b of the light-receiving surface 11. In this application, a second coloring layer 22 is provided on the light-receiving surface 11 of the cell body 10 to cover the dot marks 112, thereby reducing the color difference problem of the light-receiving surface 11 caused by the dot marks 112.

[0032] It is understood that the battery body 10 may have both a first coloring layer 21 and a second coloring layer 22 simultaneously on the edge region 11b of the light-receiving surface 11, or it may have only one of the first coloring layer 21 and the second coloring layer 22. The arrangement of the coloring layer 20 can be determined based on the presence of the wrap-around plating area 111 and the marking 112 on the light-receiving surface 11. Furthermore, when both the first coloring layer 21 and the second coloring layer 22 are present, they may completely overlap, partially overlap, or not overlap at all. This can be flexibly set according to the actual situation and is not limited here.

[0033] In some embodiments, such as Figure 3 and Figure 24 As shown, the second coloring layer 22 is bent and protrudes towards the central region 11a, and a hollow structure 221 is provided in the second coloring layer 22. By bending and protruding the second coloring layer 22 towards the central region 11a, the second coloring layer 22 can fully cover the card mark 112. Furthermore, by providing the hollow structure 221 in the second coloring layer 22, the material usage of the second coloring layer 22 can be reduced while satisfying the function of eliminating color difference at the card mark 112.

[0034] In some embodiments, the side of the light-receiving surface 11 corresponding to the dot print 112 is designated as the first side, and the maximum width of the second coloring layer 22 is less than or equal to 1500 μm along a direction perpendicular to the first side. For example, the maximum width of the second coloring layer 22 is set to: 100 μm, 300 μm, 500 μm, 600 μm, 800 μm, 1000 μm, 1200 μm, 1500 μm, etc. By setting a reasonable range for the maximum width of the second coloring layer 22, it is ensured that the second coloring layer 22 can fully cover the dot print 112, while avoiding excessive occlusion of the light-receiving surface 11 due to the second coloring layer 22 being too wide.

[0035] In some embodiments, the length of the second coloring layer 22 along a direction parallel to the first side is less than or equal to 6000 μm. Exemplarily, the maximum length of the second coloring layer 22 can be set to: 500 μm, 800 μm, 1000 μm, 2000 μm, 3000 μm, 4000 μm, 5000 μm, 6000 μm, etc. By setting a reasonable length range for the second coloring layer 22, it is possible to ensure that the second coloring layer 22 can fully cover the card dot print 112, while avoiding the second coloring layer 22 being too long, which would lead to material waste and excessive obstruction of the light-receiving surface 11.

[0036] In specific applications, the second coloring layer 22 can be prepared using 3D printing. When printing the second coloring layer 22, the movement trajectory of the printing nozzle can be flexibly set according to the size of the dot imprint 112. For example, such as... Figures 30 to 32 As shown, a schematic diagram illustrates the movement trajectory of the printhead corresponding to different sized dot prints 112. For example, Figure 30 As shown, when the maximum width of the card dot 112 is relatively small (e.g., the maximum width is 600um), the print head is made to follow... Figure 30 The printhead moves along a 1-2-3-4-5 trajectory as shown in the diagram, and its movement at point 112 is arc-shaped. (As shown...) Figure 31 As shown, when the maximum width of the second coloring layer 22 increases (for example, the maximum width is 900um), the printing nozzle is made to follow... Figure 31 The printing process follows the 1-2-3-4-5 movement trajectory shown in the diagram. The print head moves back and forth twice on the dot mark 112 to ensure that the second color layer 22 formed by printing can cover the dot mark 112. Figure 32 As shown, when the maximum width of the second coloring layer 22 is relatively large (e.g., a maximum width of 1200um), the printing nozzle is made to follow... Figure 32 The printing process follows the movement trajectory shown in Figure 1-2-3-4-5-6-7. The print head moves back and forth on the dot stamp 112 three or more times to ensure that the second color layer 22 formed by printing can cover the dot stamp 112. It should be noted that the specific printing trajectory can be flexibly set according to the size of the dot stamp 112, and is not limited here.

[0037] It should be noted that the 3D printing nozzle used for printing the coloring layer in the application can be a piezoelectric dispensing valve, a pneumatic dispensing valve, or a mechanical screw valve, etc. The specific type of control valve used by the printing nozzle can be flexibly selected according to the requirements of ink viscosity, solid content, printing accuracy and production cycle, etc., and is not limited here. In some embodiments, the solar cell in this application can be a back-contact cell, with all electrodes disposed on the back side. Back-contact cells include, but are not limited to, back-contact heterojunction solar cells (HBC cells), back-contact tunneling oxide passivated contact cells (TBC cells), composite passivated back-contact cells (HPBC cells), and back-contact hybrid cells (HBC cells). It is understood that back-contact cells do not have grid lines on the front side, thus requiring a higher aesthetic appeal on the light-receiving surface. This application further improves the uniformity of the front color of the back-contact cell and enhances its aesthetics by forming a coloring layer 20 in the edge region 11b of the cell. Of course, the solar cell in this application can also be a bifacial cell, including, but not limited to, tunneling oxide passivated contact cells (Topcon cells) and heterojunction cells (HJT cells), etc., which are not limited here.

[0038] For example, such as Figure 3As shown, the light-receiving surface 11 of the battery body 10 is provided with a first coloring layer 21 and a second coloring layer 22. Along the direction from the edge to the center of the light-receiving surface 11, the width of the second coloring layer 22 is greater than the width of the first coloring layer 21. Therefore, the second coloring layer 22 at least partially protrudes from the side of the first coloring layer 21 near the middle region 11a.

[0039] Optionally, such as Figure 2 and Figure 3 As shown, the spacing M1 between the coloring layer 20 and the side 14 of the nearest light-receiving surface 11 is less than or equal to 50 μm.

[0040] In this embodiment, by setting the spacing between the coloring layer 20 and the side 14 of the nearest light-receiving surface 11 to be less than or equal to 50 μm, it is ensured that the coloring layer 20 can effectively cover the edge position of the light-receiving surface 11, and avoids too much coloring layer 20 being exposed on the edge area 11b of the light-receiving surface 11 of the battery body 10, which would affect the aesthetics of the battery.

[0041] It is understandable that if the distance M1 between the coloring layer 20 and the side 14 of the light-receiving surface 11 is too large, many color difference areas 110 will not be effectively covered, failing to reduce the color difference of the light-receiving surface 11. Furthermore, because the surface curvature, surface roughness, and other structural features of the light-receiving surface 11 of the battery body 10 differ from those of the central area 11a in the edge region 11b, forming the coloring layer 20 in the edge region 11b of the light-receiving surface 11 places higher demands on the extensibility of the coloring material and the alignment accuracy during the process. Therefore, in this application, a certain gap can be provided between the coloring layer 20 and the side 14 of the light-receiving surface 11, allowing the portion of the color difference area 110 closest to the side 14 to be exposed. In this way, while ensuring that the color difference of the light-receiving surface 11 is reduced by setting the coloring layer 20, the processing difficulty and the amount of coloring material used can be reduced simultaneously.

[0042] Specifically, such as Figure 1 and Figure 2 As shown, the light-receiving surface 11 of the battery body 10 has a rectangular structure. The light-receiving surface 11 of the battery body 10 has four sides 14. At least one side 14 is provided with a coloring layer 20. The distance M1 between the coloring layer 20 and the corresponding side 14 can be set to: 5um, 10um, 15um, 20um, 25um, 30um, 35um, 40um, 45um, 50um, etc.

[0043] Understandably, due to the curvature and varying surface roughness of the edges of the light-receiving surface 11 of the battery body 10, the surface tension of the coloring material differs at different locations in the edge region 11b and the central region 11a. This causes the coloring material to be difficult to retain at the edges of the light-receiving surface 11 and tends to accumulate towards the center. To ensure that the coloring material can fully cover the edge region 11b, its ductility can be improved. However, increasing the ductility of the coloring material will lead to diffusion towards the center of the light-receiving surface 11, thus affecting the light absorption rate of the light-receiving surface 11.

[0044] Optionally, such as Figure 12 As shown, the solar cell also includes a substrate layer 40, which is disposed between the coloring layer 20 and the cell body 10, and the side of the substrate layer 40 closest to the intermediate region 11a is at least partially exposed to the coloring layer 20.

[0045] In this embodiment, a base layer 40 is first deposited on the light-receiving surface 11 of the battery body 10 at a position corresponding to the color difference region 110. Then, a coloring layer 20 is deposited on the base layer 40, with at least a portion of the base layer 40 near the central region 11a exposed to the coloring layer 20. Thus, during the preparation of the coloring layer 20, the surface tension of the base layer 40 restricts the diffusion of the coloring material towards the center of the light-receiving surface 11, while also ensuring sufficient coverage of the color difference region 110 at the edge of the light-receiving surface 11 by the coloring layer 20.

[0046] In some embodiments, the base layer 40 and the coloring layer 20 can be made of the same coloring material. In the actual processing, the coloring material can be first attached to the edge region 11b of the light-receiving surface 11 corresponding to the position of the color difference region 110, and the coloring material can be cured to form the base layer 40. Since the coloring material is attached directly to the battery body 10, the coloring material will diffuse towards the center of the light-receiving surface 11, so that the formed base layer 40 will partially extend and cover the light-receiving surface 11 inside the color difference region 110. The light-shielding effect of the base layer 40 on the light-receiving surface 11 can be reduced by controlling the thickness of the base layer 40, etc.

[0047] Then, a coloring material is attached to the position corresponding to the color difference area 110 on the light-receiving surface 11 again and cured to form a coloring layer 20, so that the coloring layer 20 at least partially covers the base layer 40. At this time, due to the surface tension of the base layer 40, the diffusion of the coloring material towards the center of the light-receiving surface 11 can be restricted. This can both avoid the problem of the coloring layer 20 diffusing towards the center of the light-receiving surface 11 and ensure that the coloring layer 20 fully covers the color difference area 110 at the edge of the light-receiving surface 11.

[0048] In other embodiments, the light-receiving surface 11 of the solar cell body 10 is easily scratched during storage and transportation. Therefore, a transparent protective adhesive layer is applied to the light-receiving surface 11 of the solar cell body 10 to isolate and protect it. In this application, the material of the substrate layer 40 can be the same as that of the protective adhesive layer on the light-receiving surface 11, both being made of transparent materials such as UV adhesive. This reduces the light-blocking effect of the substrate layer 40 on the light-receiving surface 11, and the substrate layer 40 can be processed simultaneously with the protective adhesive layer, thereby simplifying the processing flow, reducing processing costs, and improving processing efficiency.

[0049] It should be noted that, along the direction from the edge to the center of the light-receiving surface 11, the width of the base layer 40 is greater than the width of the coloring layer 20, so that the base layer 40 can be used to restrict the diffusion of the coloring material when preparing the coloring layer 20. The thicknesses of the base layer 40 and the coloring layer 20 can be flexibly set according to actual conditions, and are not limited here.

[0050] Furthermore, the location and shape of the substrate 40 can be determined based on the location and shape of the color difference area 110 on the light-receiving surface 11. The substrate 40 can be set as a continuous extension structure or a discontinuous arrangement structure, and can be flexibly set according to actual needs. No limitation is made here.

[0051] In some embodiments, such as Figure 13 and Figure 19 As shown, the color difference area 110 is a polished surface (e.g., a surface with a tower base structure formed after alkaline polishing), and the portion of the light-receiving surface 11 outside the color difference area 110 is provided with a textured surface 101. A transition slope 16 is formed at the junction between the polished surface and the textured surface 101, and the coloring layer 20 at least partially covers the transition slope 16.

[0052] In this embodiment, by making the portion of the light-receiving surface 11 in the color difference area 110 a polished surface, the coloring material has a smaller extensibility on the polished surface, resulting in a denser coloring layer 20. This allows for the effective covering of the color difference area 110 using a thinner and denser coloring layer 20. If the surface of the color difference area 110 is uneven, the thickness of the coloring layer 20 needs to be increased to ensure effective covering, which not only increases processing costs but also affects component processing due to the excessive thickness of the coloring layer 20. Furthermore, a textured surface 101 is provided on the portion of the light-receiving surface 11 outside the color difference area 110. The textured surface 101 enhances the light absorption and utilization of the light-receiving surface 11. A transition slope 16 is formed at the junction between the polished surface and the textured surface 101. The coloring layer 20 can partially or completely cover the transition slope 16 to ensure complete coverage of the color difference area 110 and prevent the color difference area from extending directly onto the textured surface, further improving the light absorption rate of the light-receiving surface.

[0053] Specifically, the area of ​​the light-receiving surface 11 outside the color difference zone 110 can be textured to form a pyramidal textured surface 101 to improve the light absorption rate of the light-receiving surface 11. Furthermore, the surface of the battery body 10 located within the color difference zone 110 can be a polished surface. The polished surface can be formed by alkaline polishing or other methods to create a relatively flat surface with a pyramidal structure. Compared to a textured surface, the coloring layer 20 has less extension on the polished surface, which can further limit the diffusion of the coloring layer 20 onto the textured surface 101. Of course, the surface of the battery body 10 located within the color difference zone 110 can also be textured. This textured surface can be the same size as or different from the textured surface in the middle region. Those skilled in the art can flexibly set it according to actual needs, and no limitation is made here.

[0054] When the light-receiving surface 11 has a textured surface 101, the textured surface has a larger specific surface area than the polished surface. Therefore, during the process of attaching the coloring material to the color difference area 110, the coloring material is more likely to diffuse on the textured surface 101. In one embodiment, this application can first provide a base layer 40 on the light-receiving surface 11 at the position corresponding to the color difference area 110. At this time, the material of the base layer 40 will partially diffuse onto the textured surface 101, covering the part of the textured surface 101 near the color difference area 110. Then, a coloring layer 20 is formed on the base layer 40. In this way, when the coloring material is attached to the base layer 40, the diffusion of the coloring material towards the center of the textured surface 101 can be reduced due to the restriction effect of the base layer 40, thereby ensuring that the coloring layer 20 fully covers the color difference area 110.

[0055] In some embodiments, such as Figure 13 and Figure 19As shown, the color difference area 110 is set as a polished surface (e.g., a surface with a tower-based structure formed after alkaline polishing), and the width of the polished surface is 30μm-150μm. Specifically, the width of the polished surface can be set to 30μm, 50μm, 80μm, 100μm, 120μm, 150μm, etc. By setting the width of the polished surface to 30μm-150μm, it is ensured that the coloring material can form a dense coloring layer 20 on the polished surface, thereby fully covering the polished surface and the transition slope, achieving effective masking of the color difference area 110. At the same time, it avoids the polished surface being too wide and encroaching on the textured surface area, thereby ensuring that the light-receiving surface 11 has a sufficient area of ​​textured surface to improve the light absorption and utilization efficiency. In terms of process implementation, the polished surface can be coated around the edge of the light-receiving surface 11 using a mask, protecting the silicon wafer after damage and forming the polished surface. Then, alkaline etching is used to form a textured structure in the non-mask area of ​​the light-receiving surface 11, resulting in a structure where the color difference area 110 is the polished surface and the non-color difference area is the textured surface. The width of the polished surface is controlled by adjusting the width of the mask coating. Specifically, laser or wet processes can be used to remove part of the coating. If too much coating is removed, the process requires high precision, is difficult, and can easily damage the edges of the solar cell, disrupting edge passivation. If too little coating is removed, the polished surface encroaches too much on the textured area, causing light absorption loss. Therefore, limiting the width of the polished surface to 30μm-150μm effectively protects the edge passivation while ensuring light absorption by the light-receiving surface 11, thereby improving the photoelectric conversion efficiency of the solar cell.

[0056] In some embodiments, such as Figure 26 As shown, the solar cell is a hybrid back-contact cell. The cell body 10 includes a semiconductor substrate 100 and a film structure 120 disposed on the semiconductor substrate 100. The back surface 12 of the semiconductor substrate 100 includes N-type collecting regions 1021 and P-type collecting regions 1022 alternately arranged along a certain direction. The film structure 120 in the N-type collecting region 1021 includes a tunneling oxide layer 121a and an N-type doped layer 122a stacked sequentially. Thus, a first conductive film layer is formed in the N-type collecting region 1021 by the tunneling oxide layer 121a and the N-type doped layer 122a to reduce contact resistance and improve conductivity. The film structure 120 in the P-type collecting region 1022 includes a P-type doped layer 122b. A second conductive film layer is formed in the P-type collecting region 1022 by the P-type doped layer 122b to improve passivation and suppress carrier recombination, thereby balancing passivation and conductivity and improving cell conversion efficiency. Optionally, the P-type collection region 1022 may also include an intrinsic amorphous silicon layer 121b to further enhance the passivation effect of the P-type collection region.

[0057] In some embodiments, the battery body 10 includes a semiconductor substrate 100. The light-receiving surface 11 of the semiconductor substrate 100 has a chromatic aberration region 110. In a direction away from the semiconductor substrate 100, a tunneling oxide layer 121a, an N-type doped layer 122a, a passivation layer 124, an antireflection layer 125, and a P-type doped layer 122b are sequentially disposed within the chromatic aberration region 110. The coloring layer 20 at least partially covers the P-type doped layer 122b within the chromatic aberration region 110. It should be noted that the structure of the battery body 10 can be found in [reference needed]. Figure 26 , Figure 26 The film structure within the color difference region 110 is not shown in detail. The tunneling oxide layer 121a, N-type doped layer 122a, and P-type doped layer 122b within the color difference region 110 are formed by coating around the backlight surface to the edge of the light-receiving surface 11 during the film preparation process on the backlight surface.

[0058] It is understandable that during the battery manufacturing process, due to different manufacturing processes, the reasons for the generation of color difference regions 110 on the light-receiving surface 11 are also different, and correspondingly, the film structure within the color difference regions 110 is also different.

[0059] In this embodiment, during the fabrication of the N-region and P-region film structures, the N-region film structure (including the tunneling oxide layer 121a and the N-type doped layer 122a) and the P-region film structure (including the P-type doped layer 122b) will be coated around the edge of the light-receiving surface 11, resulting in a color difference region 110 at the edge of the light-receiving surface 11. Although this coating phenomenon causes a color difference on the light-receiving surface 11, the coating can also passivate and protect the edge region 11b of the light-receiving surface 11. Therefore, in this embodiment, by retaining a portion of the N-region and P-region film structures coated around the edge of the light-receiving surface 11 and by providing a coloring layer 20 to cover the color difference region 110, the color difference of the light-receiving surface 11 can be eliminated, and the passivation and protection of the edge region 101b of the light-receiving surface 11 of the battery body 10 can be improved.

[0060] In addition, such as Figure 13 and Figure 19 As shown, in this embodiment of the battery body 10, the surface of the color difference region 110 is polished, while the portion outside the color difference region 110 is textured. The film structure within the color difference region 110 includes a tunneling oxide layer 121a, an N-type doped layer 122a, a passivation layer 124, an antireflection layer 125, and a P-type doped layer 122b, making the color difference between the color difference region 110 and other areas of the light-receiving surface 11 more obvious. Therefore, the coloring layer 20 around the edges of the light-receiving surface 11 can be set as a continuous surrounding structure, thus ensuring that the coloring layer 20 can fully cover the color difference region 110 around the edges of the light-receiving surface 11, thereby improving the effect of eliminating color difference.

[0061] Optionally, such as Figure 27 As shown, the portion of the light-receiving surface 11 outside the color difference region 110 is made of a velvety surface. In this application, by making the entire light-receiving surface 11 velvety, it is convenient to velvet the light-receiving surface 11 and also improves the light-trapping ability of the light-receiving surface 11.

[0062] In some embodiments, the battery body 10 includes a semiconductor substrate 100. The light-receiving surface 11 of the semiconductor substrate 100 has a chromatic aberration region 110. In a direction away from the semiconductor substrate 100, a passivation layer 124, an antireflection layer 125, and a p-type doped layer 122b are sequentially disposed within the chromatic aberration region 110. The coloring layer 20 at least partially covers the p-type doped layer 122b within the chromatic aberration region 110. It should be noted that the structure of the battery body 10 can be found in [reference needed]. Figure 26 , Figure 26 The film structure within the color difference region 110 is not shown in detail. The P-type doped layer 122b within the color difference region 110 is formed by winding deposition during the preparation of the P-type doped layer 122b on the backlight surface.

[0063] In this embodiment of the application, by setting the light-receiving surface 11 of the battery body 10 to a textured surface, the morphological consistency of different positions of the light-receiving surface 11 is improved, thereby reducing the appearance color difference caused by the different reflectivity of different areas of the light-receiving surface 11. At the same time, a portion of the P-region film structure (i.e., the P-type doped layer 122b) is retained at the edge of the light-receiving surface 11, which can passivate and protect the edge of the light-receiving surface 11, and at the same time, it can also reduce the degree of color difference in the edge region 11b of the light-receiving surface 11.

[0064] Furthermore, since the color difference in the color difference region 110 in this embodiment is mainly caused by the presence of the P-type doped layer 122b, the color difference is relatively small. Therefore, as Figure 25 As shown, when setting the shading layer 20, the shading layer 20 (that is...) can be... Figure 25 The first coloring layer 21) is designed as an intermittent structure, so that the coloring layer is intermittent. Only the areas with obvious color difference need to be covered by the coloring layer 20. In this way, the amount of material used in the coloring layer 20 can be reduced, thereby reducing the material cost.

[0065] In some embodiments, the thickness of the tunneling oxide layer 121a in the chromatic aberration region 110 gradually decreases along the edge of the light-receiving surface 11 towards the center, and / or the thickness of the N-type doped layer 122a gradually decreases. This reduces the light-shielding effect of the tunneling oxide layer 121a and the N-type doped layer 122a on the central region 11a of the light-receiving surface 11.

[0066] In some embodiments, the thickness of the P-type doped layer 122b in the chromatic difference region 110 gradually decreases along the edge of the light-receiving surface 11 towards the center. Further, an interface passivation layer 124 is provided between the P-type doped layer 122b and the antireflection layer 125, the interface passivation layer 124 comprising intrinsic amorphous silicon.

[0067] In another embodiment, this application selects a coloring material with relatively high viscosity, such as an ink with a viscosity greater than 5000 cps in an organosilicon system. The coloring layer 20 is formed in the color difference area 110 by 3D printing. Since the coloring material has a high viscosity, it can limit the diffusion of the coloring material to the center of the velvet surface 101, thereby ensuring that the coloring layer 20 fully covers the color difference area 110.

[0068] Optionally, such as Figures 7 to 9 As shown, the light-receiving surface 11 is also provided with an isolation protrusion 30. The isolation protrusion 30 is located on the side of the color difference area 110 near the middle region 11a. The coloring layer 20 is disposed between the isolation protrusion 30 and the side 14 of the light-receiving surface 11 and at least partially covers the color difference area 110.

[0069] In this embodiment, by first forming an isolation protrusion 30 in the edge region 11b of the light-receiving surface 11, and placing the isolation protrusion 30 on the side of the color difference region 110 close to the middle region 11a, the color layer 20 can be formed by using the isolation protrusion 30 to prevent the coloring material from diffusing towards the center of the light-receiving surface 11. This ensures that the color layer 20 covers the edge color difference region 110 of the light-receiving surface 11, thus avoiding the problem of the coloring material diffusing towards the center of the light-receiving surface 11.

[0070] In some embodiments, the light-receiving surface 11 of the solar cell body 10 is easily scratched during storage and transportation. Therefore, a transparent protective adhesive layer is provided on the light-receiving surface 11 of the solar cell body 10 to provide isolation and protection. In this application, while forming the isolation protrusion 30 on the light-receiving surface 11 of the solar cell body 10, a protective adhesive layer is prepared in the middle region 11a of the light-receiving surface 11 to provide isolation and protection, thereby preventing scratches on the light-receiving surface 11.

[0071] The isolation protrusion 30 and the protective adhesive layer can be made of transparent materials such as UV adhesive. For UV adhesive, the preferred main component is acrylic resin. In actual processing, the isolation protrusion 30 and the protective adhesive layer can be processed and formed simultaneously or separately. In addition, the isolation protrusion 30 and the protective adhesive layer can be made of the same material or different materials. This application embodiment does not limit this.

[0072] In some embodiments, such as Figure 7As shown, the orthographic projection of the isolation protrusion 30 on the light-receiving surface 11 does not overlap with the orthographic projection of the color difference area 110 on the light-receiving surface 11, that is, the isolation protrusion 30 is located on the side of the color difference area 110 near the middle region. In this way, it can be ensured that the color layer 20 can completely cover the color difference area 110, and at the same time, it can also ensure the uniformity of the thickness of the color layer 20 formed on the color difference area 110.

[0073] In other embodiments, such as Figure 9 As shown, the orthographic projection of the isolation protrusion 30 on the light-receiving surface 11 partially overlaps with the orthographic projection of the color difference region 110 on the light-receiving surface 11. That is, the color difference region 110 has a portion of the isolation protrusion 30, and the coloring layer 20 extends at least partially to cover the side of the isolation protrusion 30 away from the battery body 10. In this way, by partially placing the isolation protrusion 30 within the color difference region 110, the isolation protrusion 30 can both block the coloring material and reduce the shading of the light-receiving surface 11 by the isolation protrusion 30. At the same time, extending the coloring layer 20 to cover the side of the isolation protrusion 30 away from the battery body 10 avoids the presence of color difference at the location of the isolation protrusion 30.

[0074] In some other embodiments, such as Figure 10 As shown, the orthographic projection of the isolation protrusion 30 on the light-receiving surface 11 falls within the orthographic projection of the color difference region 110 on the light-receiving surface 11. That is, the isolation protrusion 30 is disposed within the color difference region 110, and the coloring layer 20 disposed in the color difference region 110 covers the isolation protrusion 30. In this application, by disposing of the isolation protrusion 30 within the color difference region 110, it is possible to ensure that the isolation protrusion 30 can effectively block the coloring material while reducing the obstruction of the isolation protrusion 30 to the light-receiving surface 11. At the same time, by covering the surface of the isolation protrusion 30 with the coloring layer 20, color difference can be avoided at the location where the isolation protrusion 30 is disposed.

[0075] In some embodiments, such as Figure 11 As shown, the coloring layer 20 can be formed in two stages. First, coloring material is applied to a portion of the surface near the central region 11a in the color difference area 110 and cured to form a first coloring portion 20a. The first coloring portion 20a covers a portion of the color difference area 110, with a portion of the color difference area 110 still exposed between the first coloring portion 20a and the side edge 14 of the light-receiving surface 11. Then, coloring material is applied again to the light-receiving surface 11, covering the remaining portion of the color difference area 110, and cured to form a second coloring portion 20b. In this way, the coloring layer 20 is obtained by forming in two stages. The first coloring portion 20a can be used as an isolation protrusion 30 to prevent the outer coloring material from diffusing towards the center of the light-receiving surface 11 when forming the second coloring portion 20b.

[0076] In some embodiments, such as Figure 7As shown, the width L2 of the isolation protrusion 30 is set to 20µm-200µm. Specifically, the width L2 of the isolation protrusion 30 can be set to 20µm, 50µm, 80µm, 100µm, 150µm, 200µm, etc. By setting the width range of the isolation protrusion 30, it is ensured that the isolation protrusion 30 has a certain width to play a blocking role against the coloring material, while reducing the influence of the isolation protrusion 30 on the light absorption rate of the light-receiving surface 11.

[0077] It should be noted that the width L2 of the isolation protrusion 30 in this embodiment refers to the average width of the isolation protrusion 30. During measurement, the width of the isolation protrusion 30 at different positions can be measured to obtain multiple width measurement values, and then the average value of the multiple width measurement values ​​is the width L2.

[0078] In some embodiments, such as Figure 7 As shown, along the direction perpendicular to the light-receiving surface 11, the height H2 of the isolation protrusion 30 is 5µm-30µm. Specifically, the height H2 of the isolation protrusion 30 can be set to 5µm, 10µm, 15µm, 20µm, 25µm, 300µm, etc. By setting the height range of the isolation protrusion 30, it is avoided that the isolation protrusion 30 is too low, which would not be able to effectively block the coloring material. At the same time, it is also avoided that the isolation protrusion 30 is too high, which would cause a large height difference at different positions on the surface of the battery body 10, affecting the subsequent lamination processing of the photovoltaic module.

[0079] It should be noted that the height H2 of the isolation protrusion 30 in this embodiment refers to the average height of the isolation protrusion 30. During measurement, the height of the isolation protrusion 30 at different positions can be measured to obtain multiple height measurement values, and then the average value of the multiple height measurement values ​​is the height H2.

[0080] In some embodiments, such as Figure 9 As shown, the distance L3 between the isolation protrusion 30 and the side 14 of the nearest light-receiving surface 11 is greater than or equal to 50 μm. Specifically, the distance L3 between the isolation protrusion 30 and the side 14 of the nearest light-receiving surface 11 can be set to: 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 120 μm, 150 μm, etc. By setting the distance L3 between the isolation protrusion 30 and the corresponding side 14 to be greater than or equal to 50 μm, it is ensured that while the isolation protrusion 30 can act as a barrier to the coloring material, the coloring layer 20 formed between the isolation protrusion 30 and the side 14 can fully cover the color difference area 110.

[0081] In some embodiments, such as Figure 4As shown, the width L1 of the first coloring layer 21 is 50um-500um. Specifically, the width L1 of the first coloring layer 21 can be set to 50um, 100um, 200um, 300um, 400um, 500um, etc. By setting the width range of the first coloring layer 21, it is ensured that the first coloring layer 21 can fully cover the color difference area 110 at the edge of the light-receiving surface 11, while avoiding the first coloring layer 21 being too wide and obstructing the light-receiving surface 11, thus affecting the light absorption rate of the light-receiving surface 11. At the same time, the color difference area 110 is formed due to the process in the cell manufacturing process. The width of the first coloring layer 21 is well matched with the width of the color difference area caused by film layer coating or wet etching, so no additional processing is required for the color difference area 110, reducing the process difficulty.

[0082] It should be noted that the width L1 of the first coloring layer 21 in this embodiment refers to the average width of the first coloring layer 21. During measurement, the width of the first coloring layer 21 at different positions can be measured to obtain multiple width measurement values, and then the average value of the multiple width measurement values ​​is the width L1.

[0083] In some embodiments, such as Figure 4 As shown, the width L1 of the first coloring layer 21 is 50μm-250μm. Specifically, the width L1 of the first coloring layer 21 can be set to 50μm, 80μm, 100μm, 120μm, 150μm, 200μm, 250μm, etc. By setting the width range of the first coloring layer 21, the occlusion of the effective area of ​​the light-receiving surface 11 can be minimized while ensuring that the first coloring layer 21 sufficiently covers the color difference area 110 at the edge of the light-receiving surface 11. This further reduces optical loss caused by occlusion and increases the effective light-absorbing area of ​​the light-receiving surface. At the same time, it also helps to reduce the amount of material used in the first coloring layer 21 and lowers the manufacturing cost. In terms of process, the width of the first coloring layer 21 can be controlled by controlling the width of the color difference area 110, thereby effectively covering the color difference area 110 while optimizing optical loss and material cost.

[0084] In some embodiments, such as Figure 4 As shown, along the direction perpendicular to the light-receiving surface 11, the thickness H1 of the coloring layer 20 is 5um-100um. Specifically, the thickness H1 of the coloring layer 20 can be set to 5um, 10um, 15um, 20um, 25um, 30um, 40um, 50um, 60um, 70um, 80um, 90um, 100um, etc.

[0085] Understandably, if the thickness H1 of the coloring layer 20 is less than 5 μm, the coloring layer 20 is too thin and cannot effectively shield the color difference area 110. Conversely, if the thickness H1 of the coloring layer 20 is greater than 100 μm, the coloring layer 20 is too thick, resulting in a large thickness difference between different areas of the light-receiving surface 11 of the cell body 10. This is detrimental to the subsequent lamination of the photovoltaic module and reduces reliability. Therefore, in this embodiment, by setting the thickness of the coloring layer 20 between 5 μm and 100 μm, it ensures that the color difference area 110 is effectively covered and shielded by the coloring layer 20 to reduce the color difference of the light-receiving surface 11. At the same time, it avoids affecting the module lamination process due to a large height difference between different areas of the light-receiving surface 11 of the coloring layer 20.

[0086] It should be noted that the thickness H1 of the coloring layer 20 in this embodiment refers to the maximum thickness of the coloring layer 20. During measurement, the thickness of the coloring layer 20 at different positions can be measured to obtain multiple thickness measurement values. Then, the maximum value of the multiple thickness measurement values ​​is the thickness H1.

[0087] It should be understood that the coloring layer 20 in the embodiments of this application includes a first coloring layer 21 and a second coloring layer 22. The thickness of the first coloring layer 21 and the thickness of the second coloring layer 22 can be the same or different, and there is no limitation on this.

[0088] In some embodiments, the coloring layer 20 can be formed by spraying, such as by inkjet printing. Since the viscosity of the coloring material cannot be too high when using spraying, multiple spraying processes are required. Therefore, the thickness of the resulting coloring layer 20 can be between 5µm and 30µm.

[0089] In other embodiments, the coloring layer 20 can be formed by 3D printing. Since 3D printing is used, a coloring material with relatively high viscosity can be selected, and therefore, the thickness of the resulting coloring layer 20 can be between 10µm and 100µm. It should be noted that in practical applications, the specific forming method and the thickness of the coloring layer 20 can be flexibly set as needed, and are not limited here.

[0090] Optionally, such as Figure 4 As shown, the battery body 10 also has a side surface 13 connecting the light-receiving surface 11 and the back-lighting surface 12, and the coloring layer 20 extends at least partially to cover the side surface 13. In this application, by setting the coloring layer 20 to at least partially extend to cover the side surface 13 of the battery body 10, it is possible to ensure that the coloring layer 20 can fully cover the color difference area 110 of the edge region 11b of the light-receiving surface 11. At the same time, the coloring layer 20 can also be used to passivate the side surface 13 of the battery body 10 and protect against leakage, thereby helping to improve the performance of the solar cell.

[0091] Of course, the side surface 13 of the battery body 10 may not be provided with a coloring layer 20. Those skilled in the art can flexibly set it according to actual needs, and there is no limitation here.

[0092] In some embodiments, the coloring layer 20 can be formed by 3D printing. During the printing process, the coverage area of ​​the print head extends beyond the edge of the light-receiving surface 11 by a certain distance. Then, while the coloring layer 20 is formed in the color difference area 110, the coloring layer 20 extends to cover the side surface 13 of the battery body 10, so that the side surface 13 is partially or completely covered by the coloring layer 20.

[0093] Specifically, such as Figure 18 As shown, the thickness F1 of the color layer 20 covering the color difference region 110 is between 10µm and 100µm. For example, the thickness F1 of the color layer 20 covering the color difference region 110 can be set to 10µm, 20µm, 30µm, 40µm, 50µm, 60µm, 70µm, 80µm, 90µm, 100µm, etc. This ensures that the color layer 20 can effectively cover and shield the color difference region 110, while also avoiding the impact on subsequent lamination processes of the component due to excessive thickness of the color layer 20.

[0094] It should be noted that the thickness F1 refers to the average thickness of the color layer 20 covered by the color difference area 110. Specifically, the thickness F1 can be measured by measuring the thickness of the color layer 20 covered by the color difference area 110 at different locations, and the maximum value of the multiple measured thickness values ​​is taken as the measured value of the thickness F1.

[0095] Among them, such as Figure 18 As shown, the thickness F2 of the coloring layer 20 covering the side surface 13 is greater than or equal to 2 μm. For example, the thickness F2 of the coloring layer 20 covering the side surface 13 can be set to: 2 μm, 3 μm, 5 μm, 8 μm, 10 μm, 15 μm, 20 μm, 30 μm, 40 μm, 50 μm, etc. In this way, the coloring layer 20 can not only cover the coating around the side surface 13, but also passivate and protect the side surface 13 of the cell body 10, thereby helping to improve the performance of the solar cell.

[0096] It should be noted that the thickness F2 refers to the maximum thickness of the coloring layer 20 covering the side surface 13. Specifically, the thickness F2 can be measured by measuring the thickness of the coloring layer 20 at different locations on the side surface 13, and the maximum value of the multiple measured thickness values ​​is taken as the measured value of the thickness F2.

[0097] It is understandable that the color difference area 110 may be formed when the backlight surface 12 of the battery body 10 is coated around the light-receiving surface 11. Similarly, a coating layer will also be formed on the side surface 13 of the battery body 10. The coating layer on the side surface 13 will also cause a color difference between the side surface 13 of the battery body 10 and the light-receiving surface 11 of the battery body 10. When the solar cell is made into a photovoltaic module, the color difference will also be observed when the photovoltaic module is viewed from an angle of tilt, which will affect the aesthetics of the module.

[0098] Therefore, in this embodiment of the application, during the process of printing the color layer 20 in the color difference area 110 of the light-receiving surface 11 using 3D printing, the coverage area of ​​the print head can extend beyond the edge of the battery body 10. For example, the coverage area of ​​the print head can extend beyond the edge of the battery body 10 by 50μm-130μm, thereby allowing the printed color layer 20 to extend and cover the side surface 13. Furthermore, when 3D printing the color layer 20, a coloring material with relatively high viscosity can be selected. For example, an organosilicon ink with a viscosity greater than or equal to 5000cps can be selected. This reduces the flow of the coloring material, so that a stable color layer 20 can be formed on the side surface 13, reducing the possibility of the coloring material extending to the backlight surface 12.

[0099] Optionally, such as Figure 18 and Figure 19 As shown, the highest point of the color layer 20 covered by the color difference area 110 is the first point A1, and the point at the junction of the side of the color layer 20 near the middle area 11a and the light-receiving surface 11 is the second point A2. The surface of the color layer 20 is arc-shaped from the first point A1 to the second point A2. The angle θ1 formed between the line connecting the first point A1 and the second point A2 and the light-receiving surface 11 is in the range of 10°-80°.

[0100] It is understandable that, such as Figure 18As shown, the surface of the color layer 20 covering the color difference region 110 is arc-shaped from the second point A2 to the first point A1. When the light-receiving surface 11 is irradiated by incident light, the arc-shaped structure of the color layer 20 is beneficial for reflecting the incident light to the light-receiving surface 11 at multiple angles, increasing the absorption of incident light by the battery, thereby improving the photoelectric conversion efficiency of the battery. The size of the first included angle θ1 represents the degree of inclination of the surface of the color layer 20 on the light-receiving surface 11 relative to the light-receiving surface 11. If the degree of inclination is too large, the surface curvature of the arc structure is not obvious, which weakens the reflection ability of the incident light and also makes the maximum thickness of the color layer 20 too large, affecting the subsequent processing of the photovoltaic module; while if the degree of inclination is too small, the surface of the arc structure is closer to a plane, which has poor reflection ability of the incident light, weakens the absorption of incident light by the battery, and also makes the portion of the color layer 20 near the junction with the light-receiving surface 11 thinner, unable to effectively cover the color difference region 110. Therefore, in this application, by setting the angle range of the first included angle θ1 to 30°-60°, it can ensure that the color layer 20 completely covers the color difference area 110, and also avoid the maximum thickness of the color layer 20 being too thick.

[0101] In some embodiments, such as Figure 19 As shown, the surface of the color layer 20 covered by the color difference region 110 has an arched structure (i.e., the middle part is raised upwards and the edge parts on both sides of the middle part are thinner). The color layer 20 has multiple arc-shaped structures, which further enhances the reflection of incident light, increases the absorption of light by the battery body 10, and improves battery efficiency. For example, the first included angle θ1 can be set to: 10°, 20°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 70°, 80°, etc.

[0102] Optionally, such as Figure 18 As shown, the highest point of the coloring layer 20 covered by the side surface 13 is the third point A3, and the point at the junction of the coloring layer 20 and the side surface 13 is the fourth point A4. The surface of the coloring layer is arc-shaped from the third point A3 to the fourth point A4. The angle θ2 formed between the line connecting the third point A3 and the fourth point A4 and the side surface 13 is in the range of 5°-60°.

[0103] It is understandable that, such as Figure 18As shown, the surface of the coloring layer 20 covering the side surface 13 is arc-shaped from the third point A3 to the fourth point A4. When incident light shines on the side surface 13, the arc-shaped structure of the coloring layer 20 covering the side surface 13 is conducive to the reflection and refraction of light, so that more light can enter the interior of the battery body 10, thereby increasing the light absorption rate of the battery body 10 and improving the photoelectric conversion efficiency of the battery. The size of the second included angle θ2 represents the degree of inclination of the surface of the coloring layer 20 on the side surface 13 relative to the side surface 13. If the inclination is too large, it will result in a larger maximum thickness of the coloring layer 20 on the side surface 13. During the processing, the overly thick coloring layer 20 is prone to flow towards the backlight surface 12 of the battery body 10, thereby causing shading of the backlight surface 12; while if the inclination is too small, the coloring layer 20 attached to the side surface 13 will be too thin to form an effective shading. Therefore, in this application, by setting the angle range of the second included angle θ2 to 5°-60°, it is possible to ensure that the coloring layer 20 effectively covers and blocks the side surface 13, while also avoiding the coloring layer 20 on the side surface 13 being too thick.

[0104] For example, the second included angle θ2 can be set to: 5°, 15°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, etc.

[0105] In some embodiments, the side surface 13 of the battery body 10 is a polished surface. By making the side surface 13 a polished surface, the coloring material has a smaller extensibility on the polished surface, so as to form a denser coloring layer 20 on the side surface 13. In this way, the thinner and denser coloring layer 20 can achieve the function of shielding and covering the side surface 13.

[0106] Optionally, such as Figure 18 As shown, a chamfered surface 15 is provided at the junction of the light-receiving surface 11 and the side surface 13. A coloring layer 20 covers the chamfered surface 15, and the thickness F3 of the coloring layer 20 covered by the chamfered surface 15 is greater than or equal to 2 μm. For example, the thickness F3 of the coloring layer 20 covered by the chamfered surface 15 can be set to: 2 μm, 3 μm, 5 μm, 8 μm, 10 μm, 15 μm, 20 μm, 30 μm, 40 μm, 50 μm, etc.

[0107] In this embodiment, a chamfered surface 15 is provided at the junction of the light-receiving surface 11 and the side surface 13, so that the coloring layer 20 covers the chamfered surface 15. By providing the chamfered surface 15, the transition structure at the junction of the light-receiving surface 11 and the side surface 13 is smoother, so that during the processing of the light-receiving surface 11, the coloring layer 20 can extend to the side surface 13, thereby forming an effective coverage of the side surface 13. Furthermore, the thickness of the coloring layer 20 covering the chamfered surface 15 is greater than or equal to 2 μm to ensure that the coloring layer 20 effectively covers and shields the chamfered surface 15.

[0108] Optionally, a surrounding plating layer 1110 may also be included between the coloring layer 20 and the color difference area 110, such as... Figure 3 As shown, a wrap-around coating 1110 is provided in the edge region 11b of the light-receiving surface 11 of the battery body 10, and the coloring layer 20 at least partially covers the wrap-around coating 1110. The thickness of the wrap-around coating 1110 gradually decreases along the direction from the edge region 11b to the middle region 11a.

[0109] In this embodiment, by forming a surrounding coating 1110 around the periphery 11b of the light-receiving surface 11, the passivation effect on the periphery 10 of the battery body 10 can be improved. It should be understood that when the thickness of the surrounding coating 1110 is within a certain range, the thickness of the surrounding coating 1110 is proportional to its passivation effect. On the light-receiving surface 11 of the battery body 10, there are more recombination sites near the edge, so a thicker surrounding coating 1110 is more conducive to improving the passivation effect of the edge region 11b.

[0110] Furthermore, since the color difference is more pronounced as the coating 1110 thickers, in this application, the thickness of the coloring layer 20 covered by the color difference area 110 is matched with the thickness of the coating 1110; that is, the thickness of the coloring layer 20 gradually decreases along the direction from the edge region 11b to the middle region 11a. Figure 18 and Figure 19 As shown, point A1 is closer to the edge of the light-receiving surface 11 than point A2. The thickness of the coloring layer at point A1 is set to be greater than that at point A2. This makes the thicker area of ​​the coloring layer 20 correspond to the thicker area of ​​the coating on the light-receiving surface 11, while the thinner area of ​​the coloring layer near point A2 corresponds to the thinner area of ​​the coating on the light-receiving surface 11. This makes the coverage of the color difference area 110 by the coloring layer 20 more uniform.

[0111] In some embodiments, a wrap-around coating (not shown) is further included between the coloring layer 20 and the side surface 13, and the thickness of the wrap-around coating gradually decreases along the direction from the backlight surface 12 to the light-receiving surface 11.

[0112] In this embodiment, by making the coating layer on the side surface 13 near the backlight surface 12 relatively thick, the passivation effect on the area of ​​the side surface 13 near the backlight surface 12 can be improved, thereby enhancing the structural reliability of the side of the back contact battery. Simultaneously, by making the coating layer on the side surface 13 near the light-receiving surface 11 relatively thin, the thickness of the corresponding color layer 20 is also thinner, which helps to achieve a more uniform coverage effect of the color layer 20.

[0113] In some embodiments, such as Figure 19 and Figure 20 As shown, the light-receiving surface 11 has a polished surface in the portion of the color difference region 110 and on the side surface 13. The coloring layer 20 at least partially covers the polished surface of the color difference region 110 and at least partially extends to cover the polished surface of the side surface 13. Furthermore, a wrap-around coating is provided between the polished surface and the coloring layer 20. The thickness of the wrap-around coating in the color difference region 110 gradually decreases from the edge region 11b to the middle region 11a of the light-receiving surface 11. Simultaneously, the wrap-around coating extends from the light-receiving surface 11 to the side surface 13, and the thickness of the wrap-around coating on the side surface 13 gradually decreases from the backlight surface 12 to the light-receiving surface 11. Specifically, the wrap-around coating may be a tunneling oxide layer and a doped polycrystalline silicon layer sequentially disposed away from the light-receiving surface 11, and / or the wrap-around coating may be an intrinsic amorphous silicon layer and a doped amorphous silicon layer sequentially disposed away from the light-receiving surface 11. The specific structure of the wrap-around coating can be flexibly configured according to actual needs and is not limited here.

[0114] It is understandable that during the coating process on the back surface 12 of the battery body 10, a coating layer is formed around the side surface 13 and the color difference area 110 of the light-receiving surface 11 of the battery body 10, thereby achieving passivation of the side surface 13 and the edge area 11b of the light-receiving surface 11 of the battery body 10. When the color difference area 110 and the side surface 13 are set as polished surfaces, their high flatness is conducive to the uniform deposition of the coating layer, which not only improves the film quality of the coating layer and further enhances the passivation effect on the edge area 11b and the side surface 13 of the battery body 10, but also reduces the color difference problem caused by uneven coating layer thickness. In addition, the coloring layer 20 at least partially covers the color difference area 110 and the side surface 13, which not only effectively reduces the color difference problem existing on the light-receiving surface 11 and the side surface 13 of the battery body 10, but also further improves the passivation performance of the edge area 11b and the side surface 13 of the light-receiving surface 11 of the battery body 10, and helps to reduce the edge recombination of charge carriers.

[0115] Optionally, the diffusion width of the organic matter in the coloring layer 20 into the intermediate region 11a is less than or equal to 50 μm.

[0116] Specifically, to ensure the coloring material has a certain fluidity and facilitates its processing and molding on the battery body 10, organic solvents are added to the coloring material. For example, organic solvents such as terpineol and ethylene glycol ethyl ether acetate, or organic additives such as organosilicone and fatty acid esters, are added. During the processing of the coloring layer 20 using the coloring material, the organic solvents in the coloring material diffuse towards the central region 11a of the light-receiving surface 11. If the area covered by the organic diffusion is large, it will affect the absorption of light by the light-receiving surface 11. Understandably, under an optical microscope, an organic diffusion region can be observed at the edge of the coloring layer 20. The brightness of the image corresponding to this region is significantly different from the brightness of the image corresponding to the coloring layer 20. Figure 21 As shown in the figure, the diffusion width of organic matter is L4.

[0117] The diffusion range of organic matter is related to the content of organic matter in the coloring material. In this embodiment, the coloring layer 20 can be formed by 3D printing combined with high viscosity coloring material. This can reduce the content of organic matter in the coloring material, thereby reducing the diffusion of organic matter, so that the diffusion width L4 of organic matter in the coloring layer 20 to the middle region 11a is less than or equal to 50 μm, thereby reducing the influence of organic matter diffusion on the light absorption rate of the light-receiving surface 11.

[0118] In some embodiments, the coloring layer 20 includes a substrate, a colorant, and a matting agent, wherein the substrate includes at least one of silicone or alicyclic epoxy resin, and the colorant includes carbon black.

[0119] In this embodiment, the substrate of the coloring layer 20 can be at least one of organosilicon or alicyclic epoxy resin, so that the coloring layer can be prepared by printing, and the requirements of low-temperature rapid curing can be met, reducing the diffusion of the coloring material to the center of the textured surface 101. Furthermore, carbon black is used as a colorant to match the color of the coloring layer 20 with the color of the light-receiving surface 11, and carbon black also provides reinforcement. In addition, by adding a matte agent to the coloring material, the coloring layer 20 has a certain matte finish, which can reduce the reflection of light by the coloring layer 20 and improve the light absorption rate of the battery.

[0120] It is understood that alicyclic epoxy resin is preferably used as the substrate of the coloring layer 20 in this application. On the one hand, the carboxyl groups and alicyclic groups in alicyclic epoxy resin react quickly, facilitating rapid low-temperature curing, for example, curing can be achieved at a temperature of 130℃-180℃ for 30s-60s. On the other hand, alicyclic epoxy resin has good UV resistance and weather resistance, and can maintain stable performance during long-term use. In addition, using alicyclic epoxy resin to make the coloring material can also reduce the amount of solvent used.

[0121] In some embodiments, the matting agent includes silicon dioxide. In this application, silicon dioxide is used as the matting agent, which can not only improve the surface reflectivity of the coloring layer 20, but also improve the anti-aging properties of the coloring layer 20.

[0122] Furthermore, the D50 particle size of the silica is 3µm-10µm. For example, the D50 particle size of the silica can be set to 3µm, 5µm, 7µm, 9µm, 10µm, etc. This avoids the silica particle size being too large, which would be detrimental to the dispersion of silica and would also affect the printing performance of the coloring material. On the other hand, it avoids the silica particle size being too small, which would affect the scattering effect of the coloring layer 20.

[0123] The mass percentage content of silica in the coloring layer 20 is 0.5wt%~10wt%. For example, the mass percentage content of silica is set to 0.5wt%, 1wt%, 2wt%, 5wt%, 7wt%, 10wt%, etc. By controlling the content of silica, the scattering effect of the coloring layer 20 can be improved by adding silica, while also taking into account the printability of the coloring material.

[0124] In some embodiments, carbon black is used as a colorant, and the D50 particle size of the carbon black in the coloring material is set to 3µm-10µm, for example, the D50 particle size of carbon black is set to 3µm, 4µm, 5µm, 7µm, 8µm, 10µm, etc. This avoids the carbon black particle size being too small, which is not conducive to dispersion, and also avoids the carbon black particle size being too large, which would affect the printability of the coloring material.

[0125] The carbon black content is set to a mass percentage of 0.5wt%-10wt%, for example, 0.5wt%, 1wt%, 2wt%, 5wt%, 7wt%, 10wt%, etc. By controlling the mass percentage of carbon in the coloring layer 20, it is possible to avoid the carbon black content in the coloring layer 20 being too low, resulting in a color that is too light and cannot effectively cover the color difference area 110; at the same time, it is also possible to avoid the carbon black content in the coloring layer 20 being too high, which would increase the hardness of the coloring layer 20 material, reduce the adhesion between the coloring material and the battery body 10, and make the battery body 10 prone to microcracks if the coloring layer 20 is too hard.

[0126] In some embodiments, such as Figure 28 and Figure 29 As shown, the coloring layer 20 contains carbon agglomerates 202, and the maximum one-dimensional size of the carbon agglomerates 202 is 0.5um-10um.

[0127] In this embodiment, by forming carbon agglomerates 202 in the coloring layer 20, the moderate carbon agglomerates 202 have higher light scattering efficiency than single carbon particles, which can significantly deepen the blackness and opacity of the coloring layer 20 and improve the opacity of the coloring layer 20 for the color difference area 110. At the same time, the carbon agglomerates 202 can form physical entanglement or chemical bonding with the substrate, thereby improving the wear resistance and adhesion of the coloring layer 20, reducing the risk of the coloring layer 20 falling off the battery body 10, and also improving the isolation and protection of the edge area 11b of the light-receiving surface 11 of the battery body 10.

[0128] Furthermore, during the preparation of the color layer 20 using coloring materials, the carbon agglomerates 202 present in the coloring materials can impart pseudoplastic rheological properties (i.e., shear thinning properties) to the coloring materials. Consequently, during printing or inkjet printing, the viscosity of the coloring materials decreases under shear force, which is beneficial for the transfer of the coloring materials. Moreover, when the coloring materials are left to stand after being attached to the battery body 10, the viscosity rises, which can prevent the color layer 20 from settling and dripping.

[0129] In this application, carbon agglomerates 202 are aggregated structures formed by the aggregation of primary carbon black particles in the coloring material, and can be tested and analyzed by scanning electron microscopy and energy dispersive spectroscopy. The primary particles in carbon black are its smallest structural units, and these primary particles often aggregate to form carbon agglomerates 202 due to intermolecular forces. In this application, the particle size of the primary particles is selected to be less than 30 nm. Under this condition, the carbon agglomerate size formed is moderate, resulting in better ink printability. Furthermore, using primary carbon black particles with a particle size of less than 30 nm for coloring results in a bluish hue in the prepared coloring layer 20, thereby enabling the color of the coloring layer 20 to better match the color of the light-receiving surface 11 of the battery body 10. Figure 28 As shown, the carbon agglomerate 202 is an aggregate of carbon particles with a maximum one-dimensional size of 0.5 μm to 10 μm. It should be noted that the specific preparation process of the coloring material can be flexibly set according to actual needs, as long as it can ensure that the final colored layer 20 has at least one carbon agglomerate 202, and no limitation is made here.

[0130] In some embodiments, three different sets of solar cells are selected. The cell bodies of the three sets of solar cells are manufactured using the same process. The light-receiving surface 11 of the initially prepared cell body has color difference regions around its edges, and the structures of the color difference regions are the same. Furthermore, the cell body 10 of the first set of solar cells is left untreated as Comparative Example 1; the cell body 10 of the second set of solar cells is treated with a conventional wet removal method to remove the color difference regions to obtain the final solar cell sample as Comparative Example 2; the cell body 10 of the third set of solar cells is treated with the method described in this application to form a coloring layer 20 on the color difference regions to obtain the final solar cell sample as Example 1. The performance of the three sets of solar cells is then tested.

[0131] The final test results show that the battery conversion efficiency of Example 1 is basically the same as that of Comparative Example 1; the battery conversion efficiency of Comparative Example 2 is 0.1-0.2% lower than that of Example 1. This demonstrates that the solar cell structure of this application can eliminate the color difference on the light-receiving surface 11 of the battery body 10, improving the overall aesthetics of the solar cell, while also ensuring the battery's conversion efficiency. Furthermore, the use of the coloring layer 20 in this application not only reduces the color difference on the light-receiving surface 11 but also provides passivation and leakage protection to the edges of the battery body 10, thereby helping to reduce reverse leakage current and improve the battery's PFF (fill factor) and Voc (open circuit voltage).

[0132] In other embodiments, the coverage of the coloring layer 20 is also detected using LBIC (Laser Beam Induced Current) analysis. Specifically, the sample to be tested is placed in an LBIC system, and a laser beam is used to irradiate the sample surface to generate a photocurrent. Then, the short-circuit current of the battery is measured using a lock-in amplifier, and the resulting current signal reflects the local battery characteristics. The LBIC image can reflect the structural distribution of the battery; there is no obvious current signal in the area of ​​the battery body 10 surface covered with the coloring layer 20, thus detecting the coverage of the coloring layer 20 on the surface of the battery body 10.

[0133] like Figure 22 and Figure 23 As shown, Figure 22 The image shows an LBIC test diagram of a solar cell where the color layer does not completely cover the color difference area. Figure 23 The LBIC test diagram shows that the coloring layer in a solar cell completely covers the color difference area. Figure 22 and Figure 23 The test results shown are all obtained by detecting the light-receiving surface 11 from the edge towards the center. Figure 22The results show that a current signal exists at the edge of the light-receiving surface 11, indicating that the color difference area 110 near the edge is not completely covered by the coloring layer 20; while from Figure 22 The results show that there is no obvious current signal at the edge of the light-receiving surface 11, and the color difference area 110 near the edge of the surface is completely covered by the coloring layer 20.

[0134] Optionally, such as Figure 17 As shown in the embodiments of this application, a method for preparing a solar cell is also provided, for preparing the solar cell described in the above embodiments. The preparation method includes: Step 101: Identify the light-receiving surface 11 of the battery body 10 to determine the actual position coordinates of the side 14 of the light-receiving surface 11.

[0135] Specifically, the light-receiving surface 11 of the battery body 10 is rectangular and has four sides 14. An image acquisition device is used to identify the battery body 10 in order to determine the actual position coordinates of the four sides 14 of the light-receiving surface 11 of the battery body 10.

[0136] In some embodiments, a CCD (Charge Coupled Device) camera can be used to perform image recognition on the light-receiving surface 11 of the battery body 10 and fit the actual contour shape of the light-receiving surface 11 of the battery body 10. Then, the actual position coordinates of the four sides 14 of the light-receiving surface 11 can be determined based on the actual contour shape obtained by recognition.

[0137] Specifically, such as Figure 14 As shown, the CCD camera can capture the four corners of the light-receiving surface 11 and the direction of the two sides 14 corresponding to each corner, thereby simulating and locating the actual contour shape of the light-receiving surface 11 of the battery body 10. Then, based on the actual contour shape, the actual position coordinates of the four sides 14 of the light-receiving surface 11 can be determined so that the coloring layer 20 can be processed and formed based on the actual position coordinates of each side 14.

[0138] It should be noted that other image recognition methods can also be used to determine the position of the side 14 of the light-receiving surface 11. Those skilled in the art can choose flexibly according to the actual situation, and no limitation is made here.

[0139] Step 102: Determine the coloring region 140 corresponding to the side 14 based on the actual position coordinates.

[0140] Specifically, after determining the actual position coordinates of the side 14 in step 101, based on the actual position coordinates of each side 14 and the coverage of the color difference area 110 corresponding to each side 14, the coloring area 140 corresponding to each side 14 can be determined so as to accurately set the coloring layer 20 for each side 14 and ensure that the coloring layer 20 accurately covers the color difference area 110.

[0141] Specifically, the coverage range of the color difference area 110 corresponding to each side 14 can be predetermined based on the position and size of the color difference area 110 on the light-receiving surface 11. For example, when the color difference area 110 on the light-receiving surface 11 is formed by wrap-around plating, and color difference areas 110 (i.e., wrap-around plating areas 111) exist in all four edges 11b of the light-receiving surface 11, the coverage width of the wrap-around plating area 111 corresponding to each side 14 can be predetermined. Then, based on the identified actual position coordinates of the side 14 and the coverage width of the wrap-around plating area 111 corresponding to that side 14, the coloring area 140 corresponding to that side 14 can be determined.

[0142] It should be noted that the light-receiving surface 11 has four sides 14, and a corresponding coloring area 140 can be determined for each side 14. If there is no color difference area 110 at the position corresponding to one of the sides 14, then the side 14 does not need to form a coloring layer 20.

[0143] Understandably, in the traditional solar cell manufacturing process, when it is necessary to identify the structure of the cell body 10, the usual method is to use an image recognition device to identify the outline shape of the cell body 10 in order to locate the center of the cell body 10. Then, based on the pre-set standard size of the cell body 10, the ideal outline shape of the cell body 10 is fitted. The positions of the four sides 14 of the cell body 10 can also be identified and determined according to the ideal outline shape of the cell body 10.

[0144] Due to processing errors during the manufacturing of the battery body 10, the actual manufactured battery body 10 may differ in size from the standard-sized battery body 10. Therefore, using traditional identification methods, the determined position of the side 14 of the battery body 10 may not match the actual position of the side 14 of the battery body 10. For example, ... Figure 16As shown in the figure, the solid box represents the outline shape of the identified battery body 10, and the dashed box represents the actual outline shape of the battery body 10. Obviously, there is a difference between the two. If the outline shape of the identified battery body 10 is used as the reference to determine the coloring area 140 corresponding to the side 14, the coloring area 140 may not coincide with the actual color difference area 110, or the identified color difference area may be larger than the actual color difference area. This will cause the final coloring layer 20 to not accurately cover the actual color difference area 110.

[0145] In this embodiment, by identifying the light-receiving surface 11 of the battery body 10, the actual position coordinates of the side edge 14 of the light-receiving surface are determined. Based on the actual position coordinates of the side edge 14, the corresponding colored area 140 is determined, ensuring that the final colored layer 20 can accurately cover the color difference area 110. Figure 15 As shown, this avoids both the color difference area 110 not being effectively covered and the coloring layer 20 blocking too much light-receiving surface 11, thus affecting the light absorption rate of the light-receiving surface 11.

[0146] Step 103: A coloring layer 20 is formed in the coloring area 140, such that the coloring layer 20 at least partially covers the color difference area 110 of the edge area 11b of the light-receiving surface 11.

[0147] Specifically, coloring materials can be applied to the coloring area 140 determined in step 102 using methods such as screen printing, 3D printing, or spraying. The applied coloring material is then cured to form a coloring layer 20. The curing process for the coloring material can be determined based on its properties. For example, the coloring material can be made of photosensitive ink, with the color of the ink being the same as or similar to the color of the central area 11a of the light-receiving surface 11. Furthermore, ultraviolet light irradiation can be used to cure the coloring material. Of course, other materials can also be used to make the coloring material, and the specific choice is flexible and not limited here.

[0148] In this embodiment, a coloring layer 20 is provided on the periphery 11b of the battery body 10, and the coloring layer 20 at least partially covers the color difference area 110 present in the edge area 11b, thereby reducing the color difference of the light-receiving surface 11 of the battery body 10. Using the solar cell structure of this application, the color difference problem of the light-receiving surface 11 of the battery body 10 can be effectively reduced, and damage to the edge of the battery body 10 can be avoided. Furthermore, by providing the coloring layer 20 on the edge of the battery body 10, the edge of the battery body 10 can also be passivated and leakage protected, thereby improving the performance of the solar cell.

[0149] Furthermore, this application identifies and determines the actual position coordinates of the four sides 14 of the light-receiving surface 11, and determines the corresponding colored area 140 for each side 14 based on the actual position coordinates of the sides 14. A colored layer 20 is then formed in the colored area 140. This improves the alignment accuracy between the formed colored layer 20 and the sides 14, ensuring accurate coverage of the color difference area 110 near the sides 14 by the colored layer 20, and avoiding excessive exposure of the color difference area 110 between the colored layer 20 and the corresponding sides 14. It is understood that using the preparation method of this application, the distance between the colored layer 20 and the corresponding sides 14 can be ensured to be less than or equal to 50 μm, meaning that the width of the color difference area 110 exposed at the periphery of the light-receiving surface 11 does not exceed 50 μm.

[0150] Optionally, forming the color layer 20 within the color region 140 in step 103 includes: A coloring material with the first viscosity is selected, and an initial coloring layer 20 is formed in the coloring area 140 by 3D printing. The initial coloring layer 20 is cured under preset conditions to form the coloring layer 20.

[0151] Specifically, a high-viscosity coloring material can be selected. For example, the initial viscosity of the coloring layer 20 is greater than or equal to 5000 cps. Then, the initial coloring layer 20 is formed on the surface of the color difference region 110 using 3D printing. The initial coloring layer 20 is then cured using a curing process to obtain the coloring layer 20. The specific curing process is matched to the selected coloring material. For example, when the coloring material is an acrylic resin system, UV curing can be used; or when the coloring material is an epoxy resin system or an organosilicon system, heat curing or light injection curing can be used. Light injection, as a conventional process for solar cells, can activate hydrogen atoms in the passivation film, saturate dangling bonds, reduce carrier recombination, and thus improve the efficiency of the solar cell. If silicone-based or epoxy resin-based inks are used to prepare the coloring layer 20 before the light injection process, the coloring layer can be cured simultaneously during the light injection process. This not only simplifies the production process and facilitates assembly line operation, but also further reduces surface recombination of the solar cells and improves carrier collection efficiency and battery performance while curing the coloring layer 20. When using UV-adhesive-based inks, such as acrylic resin, to prepare the coloring layer 20, UV light (i.e., ultraviolet light) irradiation can be used for curing. The specific curing process can be flexibly set according to the type of coloring material selected, and is not limited here.

[0152] In this application, the coloring layer 20 is fabricated using 3D printing. Because 3D printing can handle high-viscosity coloring materials, the diffusion of the coloring material after adhering to the surface of the battery body 10 is minimal. This allows for precise control of the coverage area of ​​the coloring layer 20, preventing unnecessary obstruction of the light-receiving surface 11. Furthermore, 3D printing only requires one pass to meet the requirements, thus shortening the processing time.

[0153] In some embodiments, thermosetting coloring materials may be selected in this application. Correspondingly, the preset conditions for curing the initial coloring layer 20 include: a curing temperature of 80℃-200℃ and a curing time of 10 s-60 s. This application uses a thermosetting method, which allows for simultaneous curing of the coloring material covering the color difference area 110 and the side surface 13, simplifying the operation process.

[0154] In some other embodiments, prior to step 101, the preparation method further includes removing a portion of the coating around the edge of the light-receiving surface 11 by laser etching or wet etching.

[0155] It is understandable that completely removing the coating around the edge of the light-receiving surface 11 would inevitably damage the edge of the battery body 10 and affect battery performance. Therefore, in this embodiment, by partially removing the coating and combining it with the covering color layer 20, the damage to the battery body 10 during the removal of the coating can be reduced, and the coverage area of ​​the color layer 20 can also be reduced, allowing more area of ​​the light-receiving surface 11 to receive light for power generation, thereby improving battery conversion efficiency.

[0156] Furthermore, during the removal of the coating around the color difference area 110 at the edge of the light-receiving surface 11, the coating around the corners of the solar cell edge can also be removed. Since the substrate silicon wafer of the solar cell is cut from a cylindrical silicon rod, there are four corner areas at the edges to reduce material waste. Therefore, during the removal of the coating around the color difference area 110 at the edge of the light-receiving surface 11, the coating around the corners can be removed as completely as possible to eliminate color differences at the corners. This way, when applying the color layer, only the color difference areas 110 corresponding to the four sides of the light-receiving surface 11 can be covered, thus avoiding linear distortion of the color layer caused by the bend at the corners, and eliminating the need to slow down the process speed at the corners, thereby improving overall production capacity.

[0157] Optionally, forming a coloring layer 20 within the coloring region 140 in step 103 includes: A base layer 40 is formed around the periphery of the light-receiving surface 11, such that the base layer 40 at least partially covers the color difference area 110; a coloring layer 20 is formed on the base layer 40.

[0158] In this application, a base layer 40 is formed by first processing and curing the edge region 11b of the light-receiving surface 11, so that the base layer 40 at least partially covers the color difference region 110, and then the coloring layer 20 is processed. By utilizing the surface tension of the base layer 40, the diffusion of the coloring material towards the center of the light-receiving surface 11 can be restricted when preparing the coloring layer 20, ensuring that the coloring layer 20 fully covers the edge of the battery body 10.

[0159] The base layer 40 can be made of the same coloring material as the coloring layer 20; or, the base layer 40 can be formed at the same time as the transparent protective adhesive layer is formed on the light-receiving surface 11, and the base layer 40 and the protective adhesive layer are made of the same transparent material.

[0160] Optionally, a coloring layer 20 is formed within the coloring area, such that the coloring layer 20 at least partially covers the color difference area 110 of the edge region of the light-receiving surface 11, including: An isolation protrusion 30 is formed around the periphery of the light-receiving surface 11, such that the isolation protrusion 30 is located on the side of the color difference area 110 near the middle region 11a of the light-receiving surface 11. A coloring layer 20 is formed between the isolation protrusion 30 and the side 14 of the light-receiving surface 11, such that the coloring layer 20 at least partially covers the color difference area 110.

[0161] It is understandable that due to the curvature and varying surface roughness of the edges of the light-receiving surface 11 of the battery body 10, the surface tension between the coloring material and different positions at the edges and center of the light-receiving surface 11 is different. This causes the coloring material to be difficult to stay at the edges of the light-receiving surface 11 and tends to accumulate towards the center of the light-receiving surface 11. Therefore, in this application, an isolation protrusion 30 is first formed in the edge region 11b of the light-receiving surface 11, with the isolation protrusion 30 located on the side of the color difference region 110 closer to the central region 11a. Then, the coloring layer 20 is processed. The isolation protrusion 30 can prevent the coloring material from diffusing towards the center of the light-receiving surface 11, ensuring that the coloring layer 20 covers the edges of the battery body 10.

[0162] In some embodiments, the isolation protrusion 30 may be made of a transparent material. When the isolation protrusion 30 is formed, a protective adhesive layer may be formed in the middle region 11a of the light-receiving surface 11 at the same time, so as to isolate and protect the light-receiving surface 11 of the battery body 10 by using the protective adhesive layer, and to prevent the light-receiving surface 11 of the battery body 10 from being scratched during storage and transportation.

[0163] Alternatively, the isolation protrusion 30 and the coloring layer 20 can be formed by spraying with a spraying device. The spraying device has two nozzles, one for forming the isolation protrusion 30 and the other for forming the coloring layer 20. Of course, the specific preparation process for the isolation protrusion 30 and the coloring layer 20 can be flexibly set according to actual conditions and is not limited here.

[0164] Optionally, such as Figure 11 As shown, forming a coloring layer 20 within the coloring region 140 may include: A first colored portion 20a is formed around the edge region 11b of the light-receiving surface 11. The first colored portion 20a partially covers the color difference region 110, and there is a gap between the first colored portion 20a and the side edge 14 of the light-receiving surface 11. A second colored portion 20b is formed within the gap, and the second colored layer 22 is connected to the first colored layer 21 to form a colored layer 20. The second colored layer 22 covers another part of the color difference area 110.

[0165] In this embodiment, the coloring layer 20 can be formed by a step-by-step molding process. First, a first coloring portion 20a is formed in the edge region 11b of the light-receiving surface 11. The first coloring portion 20a covers the part of the color difference region 110 near the middle region 11a. Then, a second coloring portion 20b is formed on the outer periphery of the first coloring portion 20a. The first coloring portion 20a can prevent the coloring material from diffusing towards the center of the light-receiving surface 11, so as to ensure that the coloring layer 20 fully covers the edge region 11b of the light-receiving surface 11.

[0166] In some embodiments, such as Figure 26 As shown, the fabrication method of the solar cell provided in this application embodiment is illustrated using a back-contact hybrid cell as an example: Example 1 S1. The semiconductor substrate 100 is cleaned and the surface of the semiconductor substrate 100 is polished using an alkaline polishing process. The polishing thickness of the front and back sides of the semiconductor substrate 100 is 5μm-10μm. The polished surface of the semiconductor substrate 100 after polishing forms a polished surface with a tower-based texture structure.

[0167] S2, a first conductive film layer is formed on the back side of the semiconductor substrate 100 using a CVD process. The first conductive film layer includes a tunneling oxide layer 121a and an N-type doped layer 122a sequentially formed on the back side of the semiconductor substrate 100. S3, a dielectric mask layer is formed on the first conductive film layer. The dielectric mask layer includes one or a combination of SiNx, SiOx, SiOxNy, etc. In steps S2 and S3, a coating layer is formed around the periphery of the semiconductor substrate 100. S4, based on a graphical design, uses a laser-based film-opening method to vaporize and ablate part of the first conductive film layer and the dielectric mask layer to form an opening area, which is the area where the P-type collection area 1022 is located. S5. Using wet etching or laser etching, or other decoupling methods, a portion of the dielectric mask layer on the front edge of the semiconductor substrate 100 is removed. The dielectric mask layer on the front edge is not completely removed, and a portion of the dielectric mask layer near the front edge of the semiconductor substrate 100 is retained. This allows the first conductive film layer under the dielectric mask layer to cover the edge and side of the semiconductor substrate 100, thereby improving the passivation effect on the edge and side of the semiconductor substrate 100. The area where the portion of the decoupling layer is retained on the front of the semiconductor substrate 100 is the color difference area 110. S6, texturing is performed on the area on the front side of the semiconductor substrate 100 without the surrounding coating and on the opening area obtained in step S4 to form a pyramid-shaped textured surface; and all dielectric mask layers are removed by wet etching or other methods. S7, a passivation layer 124 and an antireflection layer 125 are sequentially formed on the front side of the semiconductor substrate 100; S8, a second conductive film layer is formed on the back side of the semiconductor substrate 100. The second conductive film layer includes an intrinsic amorphous silicon layer 121b and a P-type doped layer 122b sequentially formed on the back side of the semiconductor substrate 100. S9, using laser to remove the second conductive film layer at the corresponding position of the N-type collection region 1021; S10, a transparent conductive layer (TCO) thin film is formed on the back side of the semiconductor substrate 100. The TCO thin film may include one or a stack of ITO (indium tin oxide), IWO (tungsten tin oxide), ITiO (titanium tin oxide), ICO (cerium tin oxide), etc. S11, a portion of the TCO film located between the N-type collection region 1021 and the P-type collection region 1022 is etched away to form an isolation opening 1023, so as to insulate and isolate the TCO film of the N-type collection region 1021 from the TCO film of the P-type collection region 1022. S12, electrode structures are fabricated on the N-type collection region 1021 and the P-type collection region 1022 respectively to obtain the battery body 10; S13, a coloring layer 20 is formed in the periphery edge region 11b of the light-receiving surface 11 of the battery body 10, so as to cover the color difference region 110 of the light-receiving surface 11 through the coloring layer 20, so as to partially or completely eliminate the color difference of the light-receiving surface 11.

[0168] It should be noted that, compared to existing technologies, Embodiment 1 of this application adds a partial decoupling step to remove a portion of the decoupling layer from the front edge of the semiconductor substrate 100, while retaining a narrower decoupling layer for subsequent masking by the coloring layer 20. This avoids damage to the battery edge caused by complete decoupling and also provides passivation and leakage protection for the battery body 10, thereby improving the product's appearance without sacrificing battery efficiency. It should be understood that when the solar cell is of other types, the processing steps can be performed similarly and will not be repeated here.

[0169] Example 2 Steps S1 to S4 are the same as in Example 1; S5. Using wet etching or laser etching, or other de-coating methods, remove all dielectric mask layers on the front edge of the semiconductor substrate 100 to increase the area of ​​the front textured surface and increase the light-trapping capability of the light-receiving surface 11.

[0170] S6, texturing is performed on the front side of the semiconductor substrate 100 and the opening area obtained in step S4 to form a textured surface with a pyramid structure. S7, a passivation layer 124 and an antireflection layer 125 are sequentially formed on the front side of the semiconductor substrate 100; S8, a second conductive film layer is formed on the back side of the semiconductor substrate 100. The second conductive film layer includes an intrinsic amorphous silicon layer 121b and a P-type doped layer 122b sequentially formed on the back side of the semiconductor substrate 100. The intrinsic amorphous silicon layer 121b and the P-type doped layer 122b are formed by wrap-around plating on the front side of the semiconductor substrate 100. The wrap-around plating area of ​​the second conductive film layer on the front side is the color difference area 110.

[0171] Steps S9 to S13 are the same as in Example 1.

[0172] It should be noted that, compared to the prior art, in Embodiment 2 of this application, by adding a partial removal of the plating layer, the plating layer on the front edge of the semiconductor substrate 100 is completely removed to reduce the color difference problem caused by the first conductive film layer and the polished surface at the front edge. However, completely removing the plating layer will reduce the passivation effect at the front edge. Therefore, a second conductive film layer is further formed on the front edge to create a plating layer. Since the second conductive film layer is thinner, the color difference in the resulting color difference area 110 is less severe. Therefore, as... Figure 25 As shown, the coloring layer 20 can be designed as an intermittent structure, only partially covering areas with significant color differences. This reduces the amount of material used in the coloring layer 20, thereby lowering material costs, and also allows for passivation of the front edge through the second conductive film layer, achieving a balance between cost control and passivation effect.

[0173] Optionally, embodiments of this application also propose a photovoltaic module, including multiple battery strings, each battery string including multiple solar cells and multiple interconnecting elements, the interconnecting elements being used to connect the multiple solar cells in series; wherein, the solar cells are the solar cells in the above embodiments. It is understandable that when solar cells are interconnected using solder ribbons, the interconnects may come into contact with the edge areas of the cells. By providing a coloring layer 20 on the four edges 11b of the cell body 10, the cells can be protected, preventing scratches during subsequent cell interconnection and thus reducing efficiency. In this embodiment, by providing a coloring layer 20 on the four edges 11b of the cell body 10, and ensuring that the coloring layer 20 at least partially covers the color difference area 110 within the edge area 11b, the color difference on the light-receiving surface 11 of the cell body 10 is reduced. Using the solar cell structure of this application, the color difference problem on the light-receiving surface 11 of the cell body 10 can be effectively reduced, and damage to the edges of the cell body 10 can be avoided. Furthermore, by providing a coloring layer 20 on the edges of the cell body 10, the edges of the cell body 10 can also be passivated and protected against leakage, thereby improving the performance of the solar cell.

[0174] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0175] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A solar cell, characterized in that, include: The battery body has a light-receiving surface and a backlighting surface arranged opposite to each other. The light-receiving surface includes a central region and an edge region arranged around the central region. A color difference area is formed in the edge region. A coloring layer is disposed in the edge region and at least partially covers the color difference region.

2. The solar cell according to claim 1, characterized in that, The color difference area includes a plating area formed in the edge area; the coloring layer includes a first coloring layer, which is disposed around the perimeter of the middle area, and the first coloring layer partially or completely covers the plating area; wherein the width of the first coloring layer is 50um-500um; or, the width of the first coloring layer is 50um-250um. And / or, the thickness of the coloring layer is 5um-100um.

3. The solar cell according to claim 1, characterized in that, The color difference area includes multiple card marks formed in the edge area, and the multiple card marks are arranged at intervals around the middle area; the coloring layer includes a second coloring layer, and the second coloring layer partially or completely covers the card marks.

4. The solar cell according to claim 3, characterized in that, The second coloring layer bends and protrudes toward the central region, and the second coloring layer has a hollow structure.

5. The solar cell according to claim 3, characterized in that, The side of the light-receiving surface corresponding to the card mark is the first side. Along the direction perpendicular to the first side, the maximum width of the second coloring layer is less than or equal to 1500um; and / or, along the direction parallel to the first side, the length of the second coloring layer is less than or equal to 6000um.

6. The solar cell according to claim 1, characterized in that, The distance between the colored layer and the side of the nearest light-receiving surface is less than or equal to 50 μm.

7. The solar cell according to any one of claims 1-6, characterized in that, It also includes a base layer disposed between the coloring layer and the battery body, wherein at least part of the side of the base layer near the intermediate region is exposed to the coloring layer.

8. The solar cell according to any one of claims 1-6, characterized in that, The light-receiving surface is also provided with an isolation protrusion, which is located on the side of the color difference area near the middle region. The coloring layer is disposed between the isolation protrusion and the side of the light-receiving surface and at least partially covers the color difference area.

9. The solar cell according to claim 8, characterized in that, The orthographic projection of the isolation protrusion on the light-receiving surface does not overlap with the orthographic projection of the color difference area on the light-receiving surface; Alternatively, the orthographic projection of the isolation protrusion on the light-receiving surface at least partially overlaps with the orthographic projection of the color difference area on the light-receiving surface, and the coloring layer at least partially extends to cover the side of the isolation protrusion away from the battery body.

10. The solar cell according to any one of claims 1-6, characterized in that, The battery body also has a side surface connecting the light-receiving surface and the back-lighting surface, and the coloring layer extends at least partially to cover the side surface.

11. The solar cell according to claim 10, characterized in that, The thickness of the coloring layer covering the color difference area is 10um-100um; And / or, the thickness of the colored layer covering the side surface is greater than or equal to 2 μm.

12. The solar cell according to claim 10, characterized in that, The highest point of the color layer covered by the color difference area is the first point, and the point at the junction of the side of the color layer near the middle area and the light-receiving surface is the second point. The surface of the color layer is arc-shaped from the first point to the second point, and the angle between the first point and the second point and the light-receiving surface is in the range of 10°-80°. And / or, the highest point of the coloring layer covered by the side surface is the third point, the point at the junction of the coloring layer and the side surface is the fourth point, the surface of the coloring layer is arc-shaped from the third point to the fourth point, and the angle between the line connecting the third point and the fourth point and the side surface is in the range of 5°-60°.

13. The solar cell according to claim 10, characterized in that, A chamfered surface is provided at the junction of the light-receiving surface and the side surface, the coloring layer covers the chamfered surface, and the thickness of the coloring layer covered by the chamfered surface is greater than or equal to 2 μm.

14. The solar cell according to claim 10, characterized in that, The color difference area is set as a polished surface, and the light-receiving surface outside the color difference area is provided with a velvety surface. A transition slope is formed at the junction between the polished surface and the velvety surface, and the coloring layer at least partially covers the transition slope. And / or, the side surface is set as a polished surface.

15. The solar cell according to claim 14, characterized in that, The width of the polished surface corresponding to the color difference area is 30μm-150μm.

16. The solar cell according to claim 14, characterized in that, The battery body includes a semiconductor substrate, and the light-receiving surface of the semiconductor substrate is provided with the chromatic aberration region. In the direction away from the semiconductor substrate, a tunneling oxide layer, an N-type doped layer, a passivation layer, an antireflection layer and a P-type doped layer are sequentially provided in the chromatic aberration region. The coloring layer at least partially covers the P-type doped layer in the chromatic aberration region.

17. The solar cell according to claim 10, characterized in that, The light-receiving surface is made of velvet in both the color difference area and the portion outside the color difference area.

18. The solar cell according to claim 17, characterized in that, The battery body includes a semiconductor substrate, and the light-receiving surface of the semiconductor substrate is provided with the chromatic aberration region. In the direction away from the semiconductor substrate, a passivation layer, an antireflection layer and a P-type doped layer are sequentially provided in the chromatic aberration region. The coloring layer at least partially covers the P-type doped layer in the chromatic aberration region.

19. The solar cell according to claim 17, characterized in that, The coloring layer covering the color difference area is intermittently arranged.

20. The solar cell according to claim 10, characterized in that, Between the coloring layer and the color difference area, there is also a wrap-around coating, the thickness of which gradually decreases along the direction from the edge region to the middle region; And / or, a wrap-around coating is further included between the coloring layer and the side surface, the thickness of which gradually decreases along the direction from the backlight surface to the light-receiving surface.

21. The solar cell according to any one of claims 1-6, characterized in that, The coloring layer includes a substrate, a colorant, and a matting agent, wherein the substrate includes at least one of organosilicon or alicyclic epoxy resin, and the colorant includes carbon black; And / or, the matting agent comprises silica, wherein the silica has a particle size of 3µm-10µm; And / or, the coloring layer contains carbon agglomerates, the maximum one-dimensional size of which is 0.5um-10um.

22. A method for preparing a solar cell, used to prepare the solar cell according to any one of claims 1-21, characterized in that, include: Identify the light-receiving surface of the battery body to determine the actual position coordinates of the side of the light-receiving surface; The coloring area corresponding to the side is determined based on the actual position coordinates; A coloring layer is formed within the coloring area, such that the coloring layer at least partially covers the color difference area at the edge of the light-receiving surface.

23. The method for preparing a solar cell according to claim 22, characterized in that, The process of forming a coloring layer within the coloring region includes: A coloring material with the highest viscosity is selected, and an initial coloring layer is formed in the coloring area using 3D printing. The initial coloring layer is cured under preset conditions to form the coloring layer.

24. The method for preparing a solar cell according to claim 23, characterized in that, The first viscosity is greater than or equal to 5000 cps; And / or, the preset conditions include: a curing temperature of 80℃-200℃ and a curing time of 10 s-60 s.

25. A photovoltaic module, characterized in that, The photovoltaic module includes multiple battery strings, each battery string including multiple solar cells and multiple interconnects, the interconnects being used to connect the multiple solar cells in series; wherein the solar cells are the solar cells according to any one of claims 1-21.

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