Photovoltaic module and conductive back plate

Abstract

The invention discloses a photovoltaic module and a conductive backboard, and the conductive layer of the photovoltaic module is provided with an insulation gap, the insulation gap is used for dividing the conductive layer into a plurality of conductive sheets, and the insulation gap comprises a plurality of main body parts roughly extending along a second direction and connecting parts connecting the adjacent main body parts; the surface of the conductive layer is provided with a plurality of texture structures extending in the second direction. The included angle a between the extending direction of the main body part and the second direction is smaller than or equal to 20 degrees. According to the invention, the binding force of the conductive layer and the insulating layer, the binding force or drawing force of the conductive body in the through hole of the conductive layer and the insulating layer, and the binding force of the conductive layer and the backboard are improved, so that the displacement and movement of the conductive layer are limited to a great extent, the current collection effect is improved, and the reliability and stability of the photovoltaic module are improved. And the continuous tearing success rate of the waste wires can be increased, the waste removing efficiency is improved, waste removing residues such as burrs are reduced, and the short circuit risk is reduced.

Description

Technical Field

[0001] This application belongs to the field of photovoltaic technology, specifically relating to a photovoltaic module and a conductive backsheet. Background Technology

[0002] Back-contact solar cells, due to their structure without grid lines on the light-facing side, can make full use of sunlight, resulting in higher efficiency.

[0003] However, individual back-contact solar cells have poor mechanical strength, are easily affected by the environment, and have very low output voltage, current, and power. Therefore, multiple back-contact solar cells are usually encapsulated into photovoltaic modules for use.

[0004] However, in existing photovoltaic modules that include a conductive layer, the bonding force between the conductive layer and the adjacent structure is weak. During the long-term service of the photovoltaic module, the conductive layer is prone to displacement or movement, which affects current collection and conduction, and also affects the reliability and stability of the photovoltaic module. Summary of the Invention

[0005] This application aims to provide a photovoltaic module and a conductive backsheet, which at least solves one of the problems in existing photovoltaic modules containing conductive layers, namely, the tendency for the conductive layer to shift or move.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows: In a first aspect, embodiments of this application propose a photovoltaic module, comprising: A battery string array, an insulating layer, a conductive layer, and a backplate are stacked in sequence; the battery string array includes: a plurality of battery strings arranged in an array; the battery strings include a plurality of back contact battery cells; the back contact battery cells include: a plurality of current collector grid lines extending along a first direction; The conductive layer has insulating gaps that divide the conductive layer into multiple conductive sheets. Each insulating gap includes a plurality of main body portions extending generally along a second direction and connecting portions connecting adjacent main body portions. The first direction is different from the second direction. The surface of the conductive layer is provided with a plurality of textured structures extending along the second direction; the angle α between the extension direction of the main body and the second direction is less than or equal to 20°.

[0007] First, compared to the flat surface of the conductive layer in existing photovoltaic modules, the textured structure of the conductive layer surface in this application has a larger surface area, which can increase the contact area between the conductive layer and the insulating layer, and between the conductive layer and the backsheet. It can also increase the contact area of ​​the conductors in the through holes of the conductive layer and the insulating layer, thereby improving the bonding force between the conductive layer and the insulating layer, the bonding force or pull-out force of the conductors in the through holes of the conductive layer and the insulating layer, and the bonding force between the conductive layer and the backsheet. This greatly restricts the displacement and movement of the conductive layer, improves the current collection effect, and enhances the reliability and stability of the photovoltaic module.

[0008] Secondly, the insulation gap is formed by removing waste from corresponding positions of the conductive layer. The insulation gap is the location of the waste removal channel. Compared to other positions on the conductive layer surface, the textured structure has a certain roughness, which may lead to a low success rate of continuous waste removal during the formation of the insulation gap, affecting the waste removal efficiency. At the same time, waste removal residue and burrs are likely to remain at the textured structure location, potentially causing short circuit risks. For example, in the process of laser waste removal, the laser energy received by the textured structure with a certain roughness is different from that of the parts outside the textured structure, resulting in a low success rate of continuous tearing off waste wire and waste removal residue at the textured structure location. Therefore, in this application, the angle α between the extension direction of the main body of the insulation gap and the second extension direction of the textured structure is less than or equal to 20°, indicating that the angle between the two is small and they are roughly parallel. The number of textured structures passing through the main body of the insulation gap is relatively small, or in other words, the number of textured structures passing through the main waste removal channel is relatively small, which can improve the success rate of continuous tearing off waste wire, improve the waste removal efficiency, and reduce waste removal residue such as burrs, thus reducing the risk of short circuits.

[0009] Third, the textured structure, due to its certain roughness, can also increase the light trapping effect, increase the optical path of light in the back contact cell, and further improve the efficiency of photovoltaic modules.

[0010] In some embodiments, the shape of the texture structure includes straight lines.

[0011] In some embodiments, the number of texture structures intersecting with one of the first main body portions is a first number, and the number of texture structures intersecting with one of the first connecting portions is a second number, the second number being greater than the first number; the first main body portion is connected to the first connecting portion, and both are adjacent to the same conductive sheet.

[0012] In some embodiments, the ratio of the second quantity to the first quantity is less than or equal to 4.

[0013] In some embodiments, the number of texture structures intersecting with one of the main body portions is less than or equal to 100.

[0014] In some embodiments, the connecting portion is arc-shaped, and the central angle b corresponding to the connecting portion is less than or equal to 180°.

[0015] In some embodiments, the first connecting portion is arc-shaped, and the diameter of the first connecting portion is smaller than the length of the first main body portion in the extending direction of the first main body portion.

[0016] In some embodiments, the back contact cell further includes: an interconnection portion electrically connected to the current collector grid line, the interconnection portion being continuously or discontinuously disposed along a third direction, the third direction being different from the first direction; at least one of the interconnection portions projecting onto the conductive layer covering at least a portion of the texture structure; and / or, At least a portion of the insulating layer corresponding to the conductive sheet has through holes, and a conductor is disposed in the through holes. The projection of at least one of the conductors on the conductive layer covers at least a portion of the texture structure.

[0017] In some embodiments, the number of texture structures covered by the projection of one interconnect portion onto the conductive layer is greater than or equal to 1; and / or, The number of texture structures covered by the projection of one of the conductors on the conductive layer is greater than or equal to 1.

[0018] In some embodiments, the extension direction of the main body located between adjacent battery strings is a fourth direction, and the angle between the second direction and the fourth direction is less than or equal to 10°.

[0019] In some embodiments, in the thickness direction of the photovoltaic module, the ratio of the depth of the texture structure to the thickness of the conductive layer is less than or equal to 25%.

[0020] In some embodiments, the ratio of the width d1 of the texture structure to the width d2 of the conductive sheet is less than or equal to 2%, the direction of the width d1 of the texture structure is perpendicular to the second direction, the direction of the width d2 of the conductive sheet is perpendicular to the third direction, and the third direction is different from the first direction.

[0021] In some embodiments, the ratio of the width d1 of the texture structure to the width d3 of the insulation gap is less than or equal to 50%, the direction of the width d1 of the texture structure is perpendicular to the second direction, and the direction of the width d3 of the insulation gap is perpendicular to the extension direction of the insulation gap.

[0022] In some embodiments, the ratio of the spacing d4 between adjacent texture structures to the width d2 of the conductive sheet is less than or equal to 20%, the direction of the spacing d4 between adjacent texture structures is perpendicular to the second direction, the direction of the width d2 of the conductive sheet is perpendicular to a third direction, and the third direction is different from the first direction.

[0023] In some embodiments, the ratio of the spacing d4 between adjacent texture structures to the width d3 of the insulation gap is less than or equal to 80%, the direction of the spacing between adjacent texture structures is perpendicular to the second direction, and the direction of the width d3 of the insulation gap is perpendicular to the extension direction of the insulation gap.

[0024] In some embodiments, the width d3 of the insulating gap is n times the spacing d4 between adjacent texture structures, where n is an integer greater than or equal to 1.

[0025] In some embodiments, the width d1 of the texture structure is 0.1 μm to 100 μm in a direction perpendicular to the second direction.

[0026] In some embodiments, the length d5 ​​of the texture structure along the second direction is 1 mm to 250 mm.

[0027] In some embodiments, the depth of the texture structure in the thickness direction of the photovoltaic module is 0.1 μm to 5 μm.

[0028] In some embodiments, the spacing d4 between adjacent texture structures is 0.1 μm to 1000 μm in a direction perpendicular to the second direction.

[0029] In some embodiments, the width d1 of the texture structure is 10 μm to 50 μm in a direction perpendicular to the second direction; and / or, In the thickness direction of the photovoltaic module, the depth of the textured structure is 1 μm to 5 μm; and / or, In a direction perpendicular to the second direction, the spacing d4 between adjacent texture structures is 100 to 800 μm.

[0030] In some embodiments, the conductive layer includes a substrate layer and an electrical connection layer covering the substrate layer on the side near the back contact cell; the surface of the conductive layer near the back contact cell is a first surface. The substrate layer is exposed in at least a partial area of ​​the first surface; the at least partial area includes: at least one gap between adjacent back-contact cells within the battery string, and / or, at least one gap between adjacent battery strings in the battery string array.

[0031] In some embodiments, on the first surface, in the region corresponding to one of the back contact cells, the length of the exposed substrate layer along the second direction is less than or equal to 5% of the length of the back contact cell along a third direction; the third direction is different from the first direction.

[0032] In some embodiments, on the first surface, in the region corresponding to one of the back contact cells, the number of exposed substrate layers is less than or equal to 10.

[0033] In some embodiments, on the first surface, the exposed substrate layer is linearly distributed, and the angle between the extension direction of the exposed substrate layer and the second direction is less than or equal to 5°; and / or, The angle between the extension direction of the exposed substrate layer and the extension direction of the main body is less than or equal to 20°.

[0034] In some embodiments, on the first surface, the exposed substrate layer and the texture structure at least partially overlap, and the depth of the texture structure at the overlapping location is greater than or equal to 0.5 μm.

[0035] In some embodiments, the back contact cell further includes: an interconnection portion electrically connected to the current collector grid line, the interconnection portion being continuously or discontinuously arranged along a third direction, the third direction being different from the first direction; at least one of the interconnection portions projecting onto the first surface avoids the exposed substrate layer.

[0036] In some embodiments, the substrate layer surface has a textured structure, wherein, per unit area: the number of textured structures on the substrate layer surface is greater than or equal to the number of textured structures on the conductive layer surface; and / or, The shape of the texture structure on the surface of the substrate layer is similar to the shape of the texture structure on the first surface; and / or, The size of the texture structure on the surface of the substrate layer is greater than or equal to the size of the texture structure on the first surface.

[0037] Secondly, embodiments of this application propose a conductive backplate, comprising: an insulating layer, a conductive layer, and a backplate stacked sequentially; An insulating gap is formed on the conductive layer to divide the conductive layer into multiple conductive sheets. The insulating gap includes a plurality of main body portions extending generally along the second direction and a connecting portion connecting adjacent main body portions. The surface of the conductive layer is provided with a plurality of textured structures extending along the second direction; the angle α between the extension direction of the main body and the second direction is less than or equal to 20°.

[0038] In some embodiments, the width d1 of the texture structure is 0.1 μm to 100 μm in a direction perpendicular to the extension direction of the texture structure; and / or, Along the second direction, the length d5 ​​of the texture structure is from 1 mm to 250 mm; and / or, In the thickness direction of the conductive backplate, the depth of the textured structure is 0.1 μm to 5 μm; and / or, In a direction perpendicular to the extension direction of the texture structure, the spacing d4 between adjacent texture structures is 0.1 μm to 1000 μm.

[0039] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0040] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 and Figure 2 Several partial three-dimensional or stacked schematic diagrams of the photovoltaic module of this application are shown; Figure 3 and Figure 4 A schematic diagram of the electrode structure of the back contact battery cell of this application is shown; Figure 5 A photograph of the conductive layer before the insulating gap was installed is shown; Figure 6 A schematic diagram of the interaction between the conductive layer and the insulating layer of this application is shown; Figure 7 A schematic diagram of the surface of the conductive layer of this application is shown; Figure 8 A partial schematic diagram of the main body surface of the conductive layer of this application is shown; Figure 9 A partial SEM image of the conductive layer before the insulating gap is installed is shown; Figure 10 A partial TEM image of the conductive layer before the insulating gap is installed is shown; Figure 11 A partial cross-sectional schematic diagram of the conductive layer of this application is shown; Figure 12 The graph shows the yield of the conductive layer of this application as a function of the included angle α.

[0041] Figure label: 1-Conductive backplate, 11-Insulating layer, 111-Through hole, 12-Conductive layer, 121-Conductive sheet, 122-Insulating gap, 1221-Main body, 1222-Connecting part, 123-Textured structure, 124-Base layer, 13-Film layer, 14-Backplate, 2-Back contact cell, 21-First current collector line, 22-Second current collector line, 23-Interconnection part, 231-First electrode disk, 232-Second electrode disk, 233-End line, 234-First main grid, 235-Second main grid, 3-Front encapsulation film, 4-Glass, 5-Conductor, 6-Insulating component. Detailed Implementation

[0042] 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.

[0043] 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.

[0044] 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.

[0045] This application provides a photovoltaic module, with reference to... Figure 1 and Figure 2Along the thickness direction Z of the photovoltaic module, the photovoltaic module includes: a battery string array, an insulating layer 11, a conductive layer 12, and a backsheet 14 stacked sequentially. The conductive layer 12 is formed of a conductive material, such as an electroplated metal conductive film of gold, silver, copper, or aluminum, or a metal foil, etc., without specific limitations. The backsheet 14 provides support for the other structures of the photovoltaic module, and its specific material is not limited; for example, it can be glass. It should be noted that, referring to... Figure 1 and Figure 2 The insulating layer 11 here can be approximately the same size as the conductive layer 12 and the backplate 14, and the insulating layer 11, conductive layer 12 and backplate 14 are stacked sequentially to form the conductive backplate 1. Alternatively, the insulating layer 11 can be smaller, and the insulating layer 11 can be approximately the same size as at least two back contact solar cells 2, with at least two back contact solar cells 2 corresponding to one insulating layer 11, and the backplate 14 corresponding to two or more insulating layers 11, all of which are within the protection scope of this application.

[0046] For details, please refer to [reference needed]. Figure 2 The photovoltaic module may further include a front encapsulating film 3 and glass 4, sequentially stacked on the light-facing side of the cell string array. The light-facing side of the photovoltaic module can refer to the side of the photovoltaic module closest to glass 4. The front encapsulating film 2 and insulating layer 11 can be made of materials such as ethylene-vinyl acetate copolymer (EVA), and the materials of the front encapsulating film 2, film layer 13, and insulating layer 11 can be the same or different; there is no limitation on their specific materials. For example, the insulating layer 11 can be a PO (polypropylene oxide)\PE (polyethylene)\PF (phenolic resin)\PET (polyethylene terephthalate) laminated structure. During normal operation of the photovoltaic module, glass 4 is located on the side that mainly receives sunlight.

[0047] The battery string array includes: a plurality of back-contact solar cells 2. The number of back-contact solar cells 2 is not limited in either the photovoltaic module or the battery string. (Refer to...) Figure 3 and Figure 4The back contact cell 2 includes a plurality of current collector grid lines extending along a first direction L1. These current collector grid lines include a first current collector grid line 21 and a second current collector grid line 22. One of the first current collector grid line 21 and the second current collector grid line 22 can be a P-type current collector grid line, and the other can be an N-type current collector grid line. The current collector grid lines are used to collect current or charge carriers in the back contact cell. Current collector grid lines with different polarities can be alternately and spaced along a third direction L4. This spacing helps avoid short circuits. The alternation means that along the third direction L4, an N-type current collector grid line can be followed by a P-type current collector grid line, and then another N-type current collector grid line. The first direction L1 differs from the third direction L4, and the angle between them is not limited; for example, they can be perpendicular or nearly perpendicular. The back contact cell can be a whole cell, or it can be a half cell, a three-part cell, a four-part cell, etc., without specific limitations.

[0048] Reference Figures 6 to 7 An insulating gap 122 is formed on the conductive layer 12 to divide the conductive layer 12 into multiple conductive sheets 121. This insulating gap 122 is typically a waste removal channel left after removing waste from the complete conductive layer. At least a portion of the conductive sheet 121 here is electrically connected to the current collector grid lines of the back-contacting solar cell. The insulating gap 122 includes a plurality of main body portions 1221 extending generally along a second direction L2 and connecting portions 1222 connecting adjacent main body portions 1221; the first direction L1 is different from the second direction L2, and the included angle between them is not limited. For example, the included angle between them is 90° or close to 90°. In a photovoltaic module, refer to... Figure 2 The insulating layer 11 typically has through holes 111 at at least a portion of the location corresponding to the conductive sheet of the conductive layer 12. A conductor 5 is typically provided in the through hole 111. The electrode structure of the conductive sheet 121 and the back contact battery cell are electrically connected through the conductor 5 within the through hole 111. The conductor 5 can be conductive adhesive, solder paste, etc., or it can contain metallic components such as silver, copper, lead, bismuth, zinc, and nickel. The specific composition of the conductor 5 is not specifically limited.

[0049] It should be noted that the main body 1221 of the insulating gap 122 refers to the portion that occupies the main body size. The main body 1221 is generally linear, or the main body 1221 generally contains linear portions. The extending direction L3 of the main body 1221 can refer to the extending direction of the linear portions. A plurality of main body portions 1221 extending generally along the second direction L2 refer to: (refer to...) Figure 6 The extension direction of each main body portion 1221 on the conductive layer 12 can be parallel to the second direction L2, or refer to... Figure 7The extension direction L3 of each main body portion 1221 on the conductive layer 12 can have a small angle with the second direction L2, such as an angle less than or equal to 20°. The connecting portion 1222 of the insulating gap 122 mainly refers to the part with a corner or a curved part. Since adjacent main body portions 1221 are arranged in parallel or have a certain angle, a connecting portion 1222 is needed to connect two adjacent main body portions 1221.

[0050] It should be noted that, Figure 7 In this configuration, a connecting part 1222 typically connects two adjacent main body parts 1221. Figure 7 L3 in the diagram only shows the extension direction of the main body 1221 on the left side of the connecting part 1222. Figure 7 In the middle, the extension direction of the main body 1221 on the left side of the connecting part 1222 is different from the extension direction of the main body 1221 on the right side of the connecting part 1222.

[0051] Reference Figures 5 to 10 The surface of the conductive layer 12 is provided with a plurality of textured structures 123 extending along the second direction L2, and the textured structures 123 have a certain roughness. Compared with the flat surface of the conductive layer in existing photovoltaic modules, the textured structures 123 on the surface of the conductive layer 12 of this application have a larger surface area, which can increase the contact area between the conductive layer 12 and the insulating layer 11, and between the conductive layer 12 and the backsheet 14. It can also increase the contact area between the conductive layer 12 and the conductors 5 in the through holes 111 of the insulating layer 11, thereby improving the bonding force between the conductive layer 12 and the insulating layer 11, the bonding force or pull-out force between the conductive layer 12 and the conductors 5 in the through holes 111 of the insulating layer 11, and the bonding force between the conductive layer 12 and the backsheet 14. This greatly restricts the displacement and movement of the conductive layer 12, improves the current collection effect, and at the same time improves the reliability and stability of the photovoltaic module. In addition, the texture structure 123 has a certain degree of roughness, which can reflect more light into the back contact cell, thereby increasing the optical path of light in the back contact cell and further improving the efficiency of the photovoltaic module.

[0052] It should be noted that in this application, SEM refers to Scanning Electron Microscopy, and TEM refers to Transmission Electron Microscopy. The surface of the conductive layer 12 can be the surface that guides the conductive layer 12 towards the insulating layer 11. The textured structure 123 on the surface of the conductive layer 12 near the insulating layer 11 can enhance the bonding force between the conductive layer 12 and the insulating layer 11, restrict the displacement and movement of the conductive layer 12, and simultaneously enhance the bonding force or pull-out force between the conductive layer 12 and the conductor 5 within the through-hole 111 of the insulating layer 11. And / or, the surface of the conductive layer 12 can be the surface that guides the conductive layer 12 towards the backplate 14. The textured structure 123 on the surface of the conductive layer 12 near the backplate 14 can enhance the bonding force between the conductive layer 12 and the backplate 14, and restrict the displacement and movement of the conductive layer 12.

[0053] Reference Figures 6 to 7 The angle α between the extension direction L3 of the main body 1221 and the second extension direction L2 of the texture structure 123 is less than or equal to 20°. Specifically, the insulating gap 122 is formed by removing waste from the corresponding position of the conductive layer 12. The insulating gap 122 is the location of the waste removal channel. Compared with other positions on the surface of the conductive layer 12, the texture structure 123 has a certain roughness. During the formation of the insulating gap 122, there may be a problem of low success rate of continuous waste removal, which may affect the waste removal efficiency. At the same time, waste removal residue is likely to exist at the location of the texture structure 123, and burrs may also be left, which may cause short circuit risk. For example, in the process of laser waste removal, the laser energy received by the texture structure 123, which has a certain roughness, is different from that received by the part outside the texture structure 123. This may result in a low success rate of continuous tearing of waste wire and waste residue at the texture structure 123. Therefore, in this application, the angle α between the extension direction L3 of the main body 1221, which occupies the main part of the insulation gap 122, and the second extension direction L2 of the texture structure is less than or equal to 20°, indicating that the angle between the two is small and they are roughly parallel. The number of texture structures 123 passing through the main body 1221 of the insulation gap 122 is relatively small, or in other words, the number of texture structures 123 passing through the main waste removal channel is relatively small. This can improve the success rate of continuous tearing of waste wire, improve the waste removal efficiency, and reduce waste residue such as burrs, thereby reducing the risk of short circuit.

[0054] For example, the angle α between the extending direction L3 of the main body 1221 and the second extending direction L2 of the texture structure 123 can be 20°, 18°, 15°, 12°, 10°, 8°, 7°, 6°, 5°, 4.5°, 4°, 3.6°, 3°, 2°, 1°, or 0.5°. Alternatively, the extending direction of the main body 1221 can be parallel to the second extending direction L2 of the texture structure 123.

[0055] It should be noted that the included angle between any two directions or two structures mentioned in this application refers to the acute angle or right angle after they intersect or extend to intersect, and generally does not refer to the obtuse angle after they intersect or extend to intersect.

[0056] It should be noted that in all the statistical processes concerning the number of texture structures 123 mentioned in this application, texture structures 123 can only be included in the statistics if their depth is greater than or equal to 0.1 μm.

[0057] In this application, when the texture structure 123 is curved, the extension direction of the texture structure 123 refers to the general trend of the texture structure, which can be determined using methods for determining the extension direction of curves in related technologies. Alternatively, within a unit length (e.g., 1 μm, 1 mm) of the curved texture structure 123, or any length of the curved texture structure, the midpoint of the line connecting its highest and lowest points can be taken as one endpoint. Then, within another unit length (e.g., 1 μm, 1 mm) of the curved texture structure 123, or any other length of the curved texture structure 123, the midpoint of the line connecting its highest and lowest points can be taken as another endpoint. The line connecting the two endpoints can be considered the extension direction of the curved texture structure 123. It should be noted that the unit length and the other unit length can be adjacent on the texture structure, or the interval between them can be within the protection scope of this application. Similarly, the arbitrary length and the other arbitrary length can be adjacent on the texture structure, or the interval between them can be within the protection scope of this application.

[0058] In this application, when the projections of two polarity collector grid lines on the surface of the insulating layer are located within a through hole 111, the collector grid line of one polarity can be electrically connected to the conductive sheet 121 of the conductive layer 12 through the conductor 5 located within the through hole 111, and the collector grid line of the other polarity can be provided with an insulating member 6 to prevent short circuits.

[0059] In some embodiments, refer to Figures 5 to 10The shape of the texture structure 123 includes straight lines. First, the main body 1221 of the insulation gap 122 is usually straight. When the angle between the extension direction L3 of the main body 1221 and the second extension direction L2 of the texture structure 123 is small or approximately parallel, the probability of the straight texture structure 123 intersecting with the main body 1221 is smaller. The number of texture structures 123 passing through the main body 1221 of the insulation gap 122 is relatively smaller, or in other words, the number of texture structures 123 passing through the main waste removal channel is relatively smaller. This can further improve the success rate of continuous waste filament tearing, improve waste removal efficiency, and further reduce waste removal residues such as burrs, reducing the risk of short circuits. Second, the processing technology of the straight texture structure 123 is simpler, which can improve production efficiency.

[0060] It should be noted that, in order to clearly show the texture structure, during the illustration process, Figure 7 It's possible that some texture structures were removed; it can be assumed that... Figure 8 It is real. Figure 7 An enlarged schematic diagram of a portion of a main body 1221. In some embodiments, refer to... Figures 7 to 8 The number of texture structures 123 intersecting with the first main body portion of one conductive sheet 121 among several main body portions 1221 is a first number, and the number of texture structures 123 intersecting with the first connecting portion of one of several connecting portions 1222 is a second number, the second number being greater than the first number; the first main body portion is connected to the first connecting portion, and both are adjacent to the same conductive sheet 121. Specifically, Figures 6 to 7 In the example where the main body part labeled 1221 is the first main body part, the connecting part 1222 that is connected to the first main body part and is labeled is the first connecting part corresponding to the first main body part. The waste removal path or channel at the connecting part 1222 is relatively short, while the waste removal path or channel at the main body is relatively long. The longer the waste removal path or channel, the lower the success rate of continuous tearing and the higher the probability of waste residue. Furthermore, the more texture structures 123 intersect with it, the more easily the waste removal channel or insulation gap is affected by the texture structure and deviates from the design position, resulting in the ineffective connection of the current collector grid lines of the conductive sheet and the back contact cell, or short circuit problems. Therefore, in this application, for the main body with a long waste removal path or channel, the first number of intersecting texture structures 123 is designed to be relatively small, and the number of texture structures through which the main waste removal channel passes is relatively small. This can improve the success rate of continuous tearing of waste wire, improve waste removal efficiency, reduce waste residue such as burrs, reduce the risk of short circuit, improve the accuracy of conductive sheet position setting, ensure the effective connection of conductive sheet and back contact cell current collector grid lines, improve current collection effect, and further reduce the risk of short circuit.

[0061] In some embodiments, the second number of texture structures intersecting the first connecting portion is greater than the first number of texture structures intersecting the first main body portion, and the ratio of the second number to the first number is less than or equal to 4. Specifically, the connecting parts usually have arcs or corners. Therefore, the success rate of continuous waste removal may be affected at the positions with arcs or corners, and the probability of waste residue may be slightly higher. In this application, since the extension direction L2 of the texture structure 123 is roughly parallel to the extension direction L3 of the main body 1221, the first number of texture structures 123 intersecting with the main body 1221 is relatively small. By controlling the ratio of the second number to the first number within the above range, the number of texture structures 123 intersecting with the first connecting part is also small, or the number of texture structures 123 intersecting with the connecting part 1222 is also small, or the second number of texture structures 123 intersecting with the connecting part 1222 is not too large. This can improve the success rate of continuous tearing of the connecting part 1222 with corners or arcs, and also reduce the waste residue of the connecting part 1222 with corners or arcs. As a result, the edge of the conductive sheet is flatter after tearing, the edge of the conductive sheet has fewer burrs, and the risk of leakage or short circuit is lower.

[0062] For example, the ratio of the second quantity to the first quantity can be 4, 3.7, 3.5, 3.1, 3, 2.8, 2.5, 2.1, 1.9, 1.5, 1.2, or 1.1.

[0063] In some embodiments, refer to Figure 6 and Figure 7Based on the fact that the second number of texture structures intersecting with the first connecting portion is greater than the first number of texture structures intersecting with the first main body portion, the shape of the connecting portion 1222 is arc-shaped, and the diameter D1 corresponding to the connecting portion 1222 is smaller than the length D2 of the main body portion 1221 in the extending direction. Specifically, if the diameter D1 corresponding to the connecting portion 1222 is smaller, the length of the waste wire removal path or waste removal channel at the connecting portion 1222 is smaller, while the length of the waste removal path or waste removal channel at the main body portion or the length D2 of the main body portion is longer. The longer the length of the waste removal path or waste removal channel or the length D2 of the main body portion, the lower the success rate of continuous tearing may be, and the higher the probability of waste residue may be. Furthermore, if there are more texture structures 123 intersecting with it, the waste removal channel or insulation gap is more easily affected by the texture structure and deviates from the design position, resulting in the current collection of the conductive sheet and the back contact cell. The grid lines cannot be effectively connected or short circuits may occur. Therefore, in this application, for the main body with a long waste removal path or waste removal channel, the first number of intersecting texture structures 123 is designed to be relatively small. The number of texture structures passing through the main waste removal channel is relatively small, which can improve the success rate of continuous tearing of waste wires, improve waste removal efficiency, and reduce waste removal residues such as burrs, thereby reducing the risk of short circuits. At the same time, it improves the accuracy of the conductive sheet's position setting, ensures the effective connection of the current collection grid lines of the conductive sheet and the back contact cell, improves the current collection effect, and further reduces the risk of short circuits.

[0064] It should be noted that the direction of the length D2 of the main body 1221 is parallel to the extension direction of the main body 1221. The diameter D1 corresponding to the connecting part 1222 refers to the chord length corresponding to the connecting part 1222 when the shape of the connecting part 1222 is arc-shaped and the central angle b corresponding to the connecting part 1222 is 180°; or, when the central angle b corresponding to the connecting part 1222 is not 180°, the chord length corresponding to a portion of the connecting part 1222 or the extended connecting part. For example, Figure 6 In the diagram, the central angle b corresponding to the connecting part 1222 is 180°, and the chord length corresponding to the connecting part 1222 is the diameter D1 corresponding to the connecting part 1222.

[0065] In some embodiments, the number of texture structures 123 intersecting with a main body portion 1221 is less than or equal to 100. Specifically, an excessive number of texture structures 123 intersecting with a main body portion 1221 will reduce the success rate of continuous tearing of the connection portion and will also result in more burrs on the edge of the conductive sheet, leading to a greater risk of leakage or short circuit. At the same time, an excessive number of texture structures 123 intersecting with a main body portion 1221 will also reduce light reflection, thereby reducing the secondary absorption of light by the back contact cell. Therefore, in this application, the number of texture structures 123 intersecting with a main body portion 1221 is less than or equal to 100, which not only has a better effect on improving the bonding force between the conductive layer 12 and the insulating layer 11, the bonding force or pull-out force of the conductor 5 in the through hole 111 of the conductive layer 12 and the insulating layer 11, and the bonding force between the conductive layer 12 and the back plate 14, but also takes into account the success rate of continuous tearing of the connection portion, as well as the risk of leakage or short circuit and light trapping. Furthermore, the number of textured structures 123 intersecting with a main body 1221 is greater than or equal to 15, which further enhances the bonding force between the conductive layer 12 and the insulating layer 11, the bonding force or pull-out force of the conductors 5 in the through holes 111 of the conductive layer 12 and the insulating layer 11, and the bonding force between the conductive layer 12 and the back sheet 14, thereby further improving the current collection effect and the reliability and stability of the photovoltaic module.

[0066] For example, the number of texture structures 123 intersecting with a main body 1221 can be: 100, 90, 80, 70, 60, 50, 40, 30, 20, 18, 15, 10, 8, 5, 1.

[0067] In some embodiments, refer to Figures 6 to 7 The connecting part 1222 is arc-shaped, and the central angle b corresponding to the connecting part 1222 is less than or equal to 180°. The smaller the central angle b corresponding to the connecting part 1222, the smaller the size of the connecting part 1222, or the shorter the arc length corresponding to the connecting part 1222. As a result, with a certain density of texture structure 123, the connecting part 1222 passes through fewer texture structures 123, further improving the success rate of continuous waste removal and further reducing the risk of leakage or short circuit.

[0068] For example, the connecting part 1222 is arc-shaped, and the central angle b corresponding to the connecting part 1222 can be 180°, 178°, 175°, 172°, 171°, 170°, or 165°.

[0069] It should be noted that the connecting part 1222 is arc-shaped. In determining the central angle b corresponding to the connecting part 1222, the following two methods can be used. One method is to take any two points A and B on the outline of the connecting part 1222, draw tangents to the arc through A and B respectively, and then draw perpendicular lines to the two tangents through A and B respectively. The intersection of the two perpendicular lines is the center O of the arc or circle. Another method is to take three points A, B, and C on the outline of the connecting part 1222, connect AC and BC, and draw the perpendicular bisectors of the two chords AC and BC respectively. The intersection point O is the center of the arc or circle. The methods for determining the center of the central angle b corresponding to the connecting part 1222 include, but are not limited to, the two examples above.

[0070] In some embodiments, refer to Figure 3 and Figure 4 The back contact cell also includes an interconnection section 23 electrically connected to the current collector grid lines, the interconnection section 23 being continuously or discontinuously arranged along a third direction L4. For example, Figure 3 In the middle, the interconnection section 23 is intermittently set along the third direction L4, and can be a back contact cell with few or even no main busbars. Figure 4 In the interconnect portion 23, the main grid is continuously arranged along a third direction L4, and it can be a back contact cell with a main grid. The third direction L4 is different from the first direction L1, and the included angle between the two can be referred to the aforementioned related descriptions. To avoid repetition, it will not be repeated here. The projection of at least one interconnect portion 23 onto the conductive layer 12 covers at least part of the texture structure 123. Specifically, in a back contact cell containing interconnect portions 23, the conductor 5 is usually provided on the surface of the interconnect portion 23 facing away from the inside of the cell. The conductor 5 protrudes from the through hole 111 to electrically connect the interconnect portion 23 of the back contact cell and the conductive sheet of the conductive layer 12. The projection of the interconnect 23 onto the conductive layer 12 covers at least a portion of the texture structure 123, and the projection of the conductor 5 onto the conductive layer 12 covers at least a portion of the texture structure 123. Since the texture structure 123 has a relatively large surface area, the contact area between the conductor 5 and the conductive layer 12 is increased, thereby increasing the adhesion or bonding force, or pull-out force, between the conductor 5 and the conductive layer 12. This further enhances the adhesion or bonding force between the back contact cell and the conductive layer, making the electrical connection between the back contact cell and the conductive layer more robust and reliable. This not only improves the current collection effect but also enhances the reliability and lifespan of the photovoltaic module.

[0071] It should be noted that, referring to Figure 3 The interconnect unit 23 may include an end line 233 located at the end of the back contact cell along a third direction L4, a first electrode disk 231 electrically connected to the first current collector line 21, and a second electrode disk 232 electrically connected to the second current collector line 22. (See reference...) Figure 4The interconnect portion 23 may include a first main gate 234 and a second main gate 235 extending along a third direction L4, as well as a first electrode disk 231 and a second electrode disk 232. The first main gate 234 and the first electrode disk 231 are both electrically connected to the first collector grid line 21, and the second main gate 235 and the second electrode disk 232 are both electrically connected to the second collector grid line 22. The electrode disk may be a pad point, etc. The reference in this application to at least one interconnect portion 23 projecting onto the conductive layer 12 and covering at least a portion of the texture structure 123 means that at least one of the following structures—the end line 233, the first electrode disk 231, the second electrode disk 232, the first main gate 234, and the second main gate 235—projecting onto the conductive layer 12 and covering at least a portion of the texture structure 123, are all within the scope of protection of this application. In some possible examples, the interconnect portion specifically refers to an electrode structure that is at least partially electrically connected to the conductor 5, or an electrode structure whose projection is at least partially located within the through-hole 111 of the insulating layer 11. For example, in some examples, the projection of the end line 233 may not be located within the through hole 111 of the insulating layer 11, in which case the end line may not be counted within the scope of the interconnection portion 23. In some examples, at least a portion of the projection of the end line 233 is located within the through hole 111 of the insulating layer 11, in which case the end line may be counted within the scope of the interconnection portion 23.

[0072] Unless otherwise specified, all projections mentioned in this application refer to orthographic projections. For example, the projection of the interconnect portion 23 onto the conductive layer 12 could refer to the projection of the interconnect portion 23 onto the conductive layer 12 when illuminated by light rays parallel to the thickness direction Z of the photovoltaic module. The determination of projections for other structures is similar, and will not be elaborated further to avoid repetition.

[0073] In some embodiments, if the number of texture structures 123 covered by the projection of an interconnect 23 on the conductive layer 12 is greater than or equal to 1, then the number of texture structures 123 covered by the projection of an interconnect 23 on the conductive layer 12 is relatively large, which further increases the contact area between the conductor 5 and the conductive layer 12, further improves the adhesion, bonding, or pull-out force between the conductor 5 and the conductive layer 12, and thus improves the adhesion, bonding, or pull-out force between the back contact cell and the conductive layer. The electrical connection between the back contact cell and the conductive layer is more robust and reliable, which can not only improve the current collection effect, but also improve the reliability and lifespan of the photovoltaic module. Furthermore, the number of texture structures 123 covered by the projection of an interconnect 23 on the conductive layer 12 is less than or equal to 20. Specifically, if the number of texture structures 123 covered by the projection of a conductor 5 on the conductive layer 12 is too large, it indicates that the texture structure is too dense, which will reduce the success rate of continuous tearing of the connection part, and will also result in more burrs on the edge of the conductive sheet, increasing the risk of leakage or short circuit. At the same time, an excessive number of texture structures 123 covered by the projection of the interconnect 23 on the conductive layer 12 will also reduce light reflection, thereby reducing the secondary light reflection of the back contact cell. Therefore, in this application, the number of texture structures 123 covered by the projection of the interconnect 23 on the conductive layer 12 is less than or equal to 20. This not only improves the adhesion, bonding, or pull-out force between the conductor 5 and the conductive layer 12, but also improves the adhesion, bonding, or pull-out force between the back contact cell and the conductive layer. The electrical connection between the back contact cell and the conductive layer is more robust and reliable. This not only improves the current collection effect, but also improves the reliability and lifespan of the photovoltaic module. Furthermore, it takes into account the success rate of continuous tearing of the connection part, as well as the risk of leakage or short circuit and light trapping.

[0074] For example, the number of texture structures 123 covered by the projection of an interconnect 23 onto the conductive layer 12 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20.

[0075] Reference Figure 2 At least a portion of the insulating layer 11, corresponding to the conductive sheet of the conductive layer 12, has through holes 111, and a conductor 5 is disposed in the through holes 111. In some embodiments, the projection of at least one conductor 5 onto the conductive layer 12 covers at least a portion of the texture structure 123, which also increases the contact area between the conductor 5 and the conductive layer 12, further improving the adhesion, bonding, or pull-out force between the conductor 5 and the conductive layer 12, thereby improving the adhesion, bonding, or pull-out force between the back contact cell and the conductive layer. The electrical connection between the back contact cell and the conductive layer is more robust and reliable, which can not only improve the current collection effect, but also improve the reliability and lifespan of the photovoltaic module.

[0076] In some embodiments, if the number of texture structures 123 covered by the projection of a conductor 5 on the conductive layer 12 is greater than or equal to 1, the contact area between the conductor 5 and the conductive layer 12 is further increased, thereby enhancing the adhesion, bonding, or pull-out force between the conductor 5 and the conductive layer 12. This, in turn, improves the adhesion, bonding, or pull-out force between the back contact cell and the conductive layer, resulting in a more robust and reliable electrical connection between the back contact cell and the conductive layer. This not only improves the current collection effect but also enhances the reliability and lifespan of the photovoltaic module. Furthermore, if the number of texture structures 123 covered by the projection of a conductor 5 on the conductive layer 12 is less than or equal to 20, specifically, an excessively large number of texture structures 123 indicates an overly dense texture structure, which reduces the success rate of continuous tearing of the connection and leads to more burrs on the edges of the conductive sheet, increasing the risk of leakage or short circuit. Additionally, an excessively large number of texture structures 123 covered by the projection of the interconnect 23 on the conductive layer 12 also reduces light reflection, thereby reducing the back contact cell's ability to reflect light. Therefore, in this application, the number of texture structures 123 covered by the projection of the conductor 5 on the conductive layer 12 is less than or equal to 20. This not only improves the adhesion, bonding, or pull-out force between the conductor 5 and the conductive layer 12, but also improves the adhesion, bonding, or pull-out force between the back contact cell and the conductive layer. The electrical connection between the back contact cell and the conductive layer is more robust and reliable, which can improve the current collection effect, as well as the reliability and lifespan of the photovoltaic module. It also takes into account the success rate of continuous tear-off of the connection part, as well as the risk of leakage or short circuit and light trapping.

[0077] For example, the number of texture structures 123 covered by the projection of a conductor 5 on the conductive layer 12 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20.

[0078] In some embodiments, the extension direction of the main body 1221 located between adjacent battery strings is a fourth direction, and the angle between the extension direction of the textured structure and the fourth direction is less than or equal to 10°. Specifically, the main body 1221 located between adjacent battery strings serves to support two battery strings. The risk of short circuits or leakage caused by residual waste in the conductive layer at this location is greater. Therefore, the angle between the extension direction of the main body 1221 at this location and the extension direction of the textured structure 123, or the second direction L2, is smaller and more parallel. This further improves the success rate of continuous waste removal and further reduces the waste residue at the connection portion 1221 at this location, thereby further reducing the risk of leakage or short circuit and improving the reliability of the photovoltaic module.

[0079] For example, the extension direction of the main body 1221 located between adjacent battery strings is the fourth direction, and the angle between the extension direction of the texture structure and the fourth direction can be 10°, 9°, 8°, 7°, 6°, 5°, 4°, 3°, 2°, 1°, or 0.3°. Alternatively, the extension direction of the main body 1221 located between adjacent battery strings is the fourth direction, and the extension direction of the texture structure, i.e., the second direction L2, is parallel to the fourth direction.

[0080] It should be noted that, in this application, the main body portion 1221 located between adjacent cell strings can refer to a main body portion positioned closer to the center of the adjacent cell strings. For photovoltaic modules with string spacing, the main body portion 1221 located between adjacent cell strings can refer to a main body portion positioned closer to the center of the string spacing between adjacent cell strings, etc. This application does not specifically limit this. For example, the main body portion 1221 located between adjacent cell strings can refer to a main body portion located within the string spacing between adjacent cell strings, or a main body portion close to the string spacing, etc.

[0081] Figure 11 This is a partial cross-sectional schematic diagram of the conductive layer. In some embodiments, reference is made to... Figure 11 In the thickness direction Z of the photovoltaic module, the ratio of the depth H1 of the texture structure 123 to the thickness H2 of the conductive layer 12 is less than or equal to 25%. Specifically, the ratio of the depth H1 of the texture structure 123 to the thickness H2 of the conductive layer 12 exceeds 25%, indicating that the difference between the depth of the texture structure and the thickness of the conductive layer is too large. During the laser removal process, the laser energy required for the texture structure 123 differs too much from the laser energy required for other locations on the conductive layer 12. To achieve the same removal rate, it may be necessary to change the laser power, otherwise it may easily lead to over-ablation or incomplete removal, resulting in a complex process. If the same laser is used for removal, it may easily lead to over-removal, causing ablation of the conductive layer, or incomplete removal, causing leakage or short circuit risks. Therefore, in this application, the ratio of the depth of the texture structure 123 to the thickness of the conductive layer 12 is less than or equal to 25%, indicating that the difference between the depth of the texture structure 123 and the thickness of the conductive layer is not too large. When the same laser is used for removal, not only is thorough removal guaranteed, but also excessive ablation is avoided. Moreover, the removal process only requires the use of the same laser, making the process simpler.

[0082] For example, the ratio of the depth of the texture structure 123 to the thickness of the conductive layer 12 can be 25%, 23%, 20%, 18%, 15%, 12%, 10%, 8%, 5%, 2.5%, 2%, or 1.5%.

[0083] It should be noted that the thickness of the conductive layer 12 can be the thickness of the entire conductive layer at the location of the texture structure 123, or the thickness at other locations outside the texture structure 123, without any specific limitation.

[0084] In some embodiments, refer to Figure 11 The texture structure 123 is a groove structure. In this case, the thickness H1 of the texture structure 123 is: along the thickness direction Z of the photovoltaic module or conductive layer 12, from the surface of the conductive layer 12 with the texture structure 123 ( Figure 11 The depth of the texture structure 123 is the dimension from the upper surface of the conductive layer to the bottom of the groove structure.

[0085] It should be noted that a textured structure that protrudes from the conductive layer is also within the scope of protection of this application. In the case where the textured structure is a protruding structure protruding from the conductive layer, the thickness of the textured structure is: along the thickness direction of the photovoltaic module or the conductive layer, from the surface of the conductive layer with the textured structure to the dimension of the protruding structure away from the surface of the conductive layer with the textured structure.

[0086] In some embodiments, refer to Figure 11 The thickness H2 of the conductive layer 12 can be from 20μm to 60μm. On the one hand, the success rate of continuous tearing of the conductive layer 12 within the above range is higher, and the conductivity is better, without wasting materials.

[0087] In some embodiments, refer to Figures 3 to 4 , Figures 6 to 7 The ratio of the width d1 of the texture structure 123 to the width d2 of the conductive sheet 121 is less than or equal to 2%. Specifically, if this ratio is greater than 2%, it indicates that the texture structure 123 is too wide. Due to the presence of a wider texture structure 123, it may be necessary to change the laser power to achieve the same waste removal rate. Otherwise, it may easily lead to over-ablation or incomplete waste removal, resulting in a complex process. If the same laser is used for waste removal, it may easily lead to over-ablation, causing ablation of the conductive layer, or incomplete waste removal, causing leakage or short circuit risks. Therefore, in this application, the ratio of the width of the texture structure 123 to the width of the conductive sheet 121 of the conductive layer 12 is less than or equal to 2%, indicating that the width of the texture structure 123 is not too large. When the same laser is used for waste removal, not only is thorough waste removal guaranteed, but also transitional ablation is avoided. Moreover, the waste removal process only requires the use of the same laser, making the process simpler.

[0088] For example, the ratio of the width d1 of the texture structure 123 to the width d2 of the conductive sheet 121 can be 2%, 1.8%, 1.5%, 1.1%, 1%, 9.8‰, 5‰, 2‰, 1‰, 0.8‰, 0.5‰, 0.3‰, 0.1‰, 0.067‰, or 0.05‰.

[0089] It should be noted that the direction of the width d1 of the texture structure 123 is perpendicular to the second direction L2, and the direction of the width d2 of the conductive sheet 121 is perpendicular to the third direction L4. The third direction L4 is different from the first direction L1, and the included angle between them can be referred to the aforementioned relevant descriptions. To avoid repetition, it will not be repeated here. The width of the conductive sheet 121 can refer to the width corresponding to the midpoint of the conductive sheet in the third direction. In some embodiments, the width d2 of the conductive sheet 121 can be 5mm to 15mm. The width d2 of the conductive sheet 121 is more suitable, as it not only provides a good electrical connection with the current collector grid lines of the back contact battery cell, but also avoids being too wide to cause a short circuit. When the width of the texture structure 123 is different at different positions, it can be the arithmetic mean of the widths at two or more positions. In this application, when a certain dimension of other structures is different at different positions, it can also be the arithmetic mean of that dimension at two or more positions. To avoid repetition, it will not be repeated here.

[0090] In some embodiments, refer to Figures 6 to 7 The ratio of the width d1 of the texture structure 123 to the width d3 of the insulation gap 122 is less than or equal to 50%. The direction of the width d1 of the texture structure 123 is perpendicular to the extension direction of the texture structure, and the direction of the width d3 of the insulation gap 122 is perpendicular to the extension direction of the insulation gap. Specifically, if this ratio is greater than 50%, it indicates that the texture structure 123 is too wide. Due to the presence of a wider texture structure 123, it may be necessary to change the laser power to achieve the same waste removal rate. Otherwise, it may easily lead to over-ablation or incomplete waste removal, resulting in a complex process. If the same laser is used for waste removal, it may easily lead to over-ablation, causing ablation of the conductive layer, or incomplete waste removal, causing leakage or short circuit risks. Therefore, in this application, the ratio of the width d1 of the texture structure 123 to the width d3 of the insulation gap 122 is less than or equal to 50%, indicating that the width of the texture structure 123 is not too large. When the same laser is used for waste removal, not only is thorough waste removal guaranteed, but also transitional ablation is avoided. Moreover, the waste removal process only requires the use of the same laser, making the process simpler.

[0091] For example, the ratio of the width d1 of the texture structure 123 to the width d3 of the insulation gap 122 can be 50%, 40%, 30%, 20%, 10%, 8%, 5%, 3%, 1%, 0.5%, 0.1%, 0.05%, 0.01%, or 0.002%.

[0092] It should be noted that when the width of the insulation gap 122 varies at different locations, it can be the arithmetic mean of the widths at two or more locations. Similarly, in this application, when a certain dimension of other structures varies at different locations, it can also be the arithmetic mean of that dimension at two or more locations; to avoid repetition, this will not be elaborated further. The width d3 of the insulation gap 122 in the main body 1221 is perpendicular to the extension direction of the straight line segment within the main body 1221. When the connecting part is arc-shaped, the width d3 of the insulation gap 122 in the connecting part 1222 is perpendicular to the tangent direction of the connecting part 1222.

[0093] In some embodiments, the width d3 of the insulation gap 122 can be from 0.2 mm to 5 mm. When the width d3 of the insulation gap 122 is within the above range, not only is the success rate of continuous waste removal high, but material waste is also avoided.

[0094] In some embodiments, refer to Figure 3 , Figure 4 , Figures 6 to 7 The ratio of the spacing d4 between adjacent texture structures 123 to the width d2 of conductive sheet 121 is less than or equal to 20%. The direction of the spacing d4 between adjacent texture structures 123 is perpendicular to the extension direction of texture structure 123. The direction of the width d2 of conductive sheet is perpendicular to the third direction L4. The third direction L4 is different from the first direction L1. The included angle between the two is as described above. If the ratio of the spacing d4 between adjacent texture structures 123 to the width d2 of conductive sheet 121 is too small, it indicates that the texture structure 123 is too dense. An overly dense texture structure 123 may have adverse effects on the success rate of continuous waste removal and leakage risk. If the ratio is too large, it indicates that the texture structure is too sparse. Too sparse a texture structure will not effectively limit the conductive layer or promote the bonding force and pull-out force between the conductive layer and the surrounding structure. If the ratio of the spacing d4 between adjacent texture structures 123 to the width d2 of conductive sheet 121 is within the above range, it will balance the success rate of continuous waste removal, leakage risk, and bonding force and pull-out force, resulting in a higher success rate of continuous waste removal, a lower leakage risk in photovoltaic modules, better limiting effect on conductive layer 12, and better current collection effect.

[0095] For example, the ratio of the spacing d4 between adjacent texture structures 123 to the width d2 of conductive sheet 121 can be 20%, 15%, 10%, 8%, 5%, 3%, 1%, 0.5%, 0.1%, 9.8‰, 5‰, 2‰, 1‰, 0.8‰, 0.5‰, 0.3‰, 0.1‰, 0.067‰, or 0.05‰.

[0096] In some embodiments, refer to Figure 3 , Figure 4 , Figures 6 to 7The ratio of the spacing d4 between adjacent texture structures 123 to the width d3 of the insulation gap 122 is 80%, and the direction of the spacing d4 between adjacent texture structures 123 is perpendicular to the extension direction of the texture structure 123. If the ratio of the spacing d4 between adjacent texture structures 123 to the width d3 of the insulation gap 122 is too small, it indicates that the texture structure 123 is too dense. An overly dense texture structure 123 may have adverse effects on the continuous waste removal success rate and leakage risk. If the ratio is too large, it indicates that the texture structure is too sparse. Too sparse a texture structure will not effectively limit the conductive layer or promote the bonding force or pull-out force between the conductive layer and the surrounding structure. The ratio of the spacing d4 between adjacent texture structures 123 to the width d3 of the insulation gap 122 is within the above range, which balances the continuous waste removal success rate, leakage risk, and bonding force or pull-out force improvement. This results in a higher continuous waste removal success rate, a lower leakage risk in the photovoltaic module, better limiting effect on the conductive layer 12, and better current collection effect.

[0097] For example, the ratio of the spacing d4 between adjacent texture structures 123 to the width d3 of the insulation gap 122 can be 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, 8%, 5%, 3%, 1%, 0.5%, 0.1%, 0.05%, 0.01%, or 0.001%.

[0098] In some embodiments, the width d3 of the insulating gap 122 is n times the spacing d4 between adjacent texture structures 123, where n is an integer greater than or equal to 1. Specifically, the texture structure can be a groove structure or a similar groove structure. When d3 is n times d4, the outline of the insulating gap 122 can be exactly within the texture structure. Since the groove can reduce the difficulty of waste removal and improve the success rate of continuous waste removal, it can reduce burrs on the edge of the conductive sheet, further reducing the risk of short circuits or leakage. For example, n here can be 1, 2, 3, 4, or 5.

[0099] In some embodiments, refer to Figure 7In the direction perpendicular to the extension direction of the texture structure 123, the width d1 of the texture structure 123 is 0.1 μm to 100 μm. If the width d1 of the texture structure 123 is too small, the confinement of the conductive layer or the improvement of the bonding force or pull-out force between the conductive layer and the surrounding structure will be poor. If the width d1 of the texture structure 123 is too large, it may have adverse effects on the continuous waste removal success rate and leakage risk. Therefore, in this application, the width d1 of the texture structure 123 is within the above range, which takes into account the continuous waste removal success rate, leakage risk, and bonding force or pull-out force improvement, resulting in a high continuous waste removal success rate, low leakage risk in photovoltaic modules, good confinement effect on the conductive layer 12, and good current collection effect. Furthermore, in the direction perpendicular to the extension direction of the texture structure 123, the width d1 of the texture structure 123 is 10 μm to 50 μm to further improve the continuous waste removal success rate, leakage risk, and bonding force or pull-out force, and further reduce leakage risk.

[0100] For example, the width d1 of the texture structure 123 can be 0.1μm, 0.5μm, 1μm, 2μm, 5μm, 8μm, 10μm, 12μm, 15μm, 20μm, 50μm, 80μm, or 100μm.

[0101] In some embodiments, refer to Figure 7 Along the extension direction of the texture structure 123 (i.e., the second reverse L2), the length d5 ​​of the texture structure 123 is from 1 mm to 250 mm. Specifically, if the length d5 ​​of the texture structure 123 is too small, the limiting effect on the conductive layer, or the promotion of the bonding force or pull-out force between the conductive layer and the surrounding structure, will be poor. If the length d5 ​​of the texture structure 123 is too large, it may have adverse effects on the continuous waste removal success rate and leakage risk. Therefore, in this application, the length d5 ​​of the texture structure 123 is within the above range, which takes into account the continuous waste removal success rate, leakage risk, and bonding force or pull-out force improvement, resulting in a higher continuous waste removal success rate, a lower leakage risk in the photovoltaic module, a better limiting effect on the conductive layer 12, and a better current collection effect.

[0102] For example, the length d5 ​​of texture structure 123 is 1mm, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 80mm, 100mm, 120mm, 150mm, 170mm, 190mm, 200mm, 220mm, 250mm.

[0103] In some embodiments, refer to Figure 11In the thickness direction Z of the photovoltaic module, the depth H1 of the texture structure is 0.1μm to 5μm, and the depth of the texture structure 123 exceeds 5μm. This indicates that the difference between the depth of the texture structure and the thickness of the conductive layer is too large. During the laser removal process, the laser energy required for the texture structure 123 is too different from the laser energy required for other positions of the conductive layer 12. In order to achieve the same removal rate, it may be necessary to change the laser power, etc. Otherwise, it may easily lead to over-ablation or incomplete removal, resulting in a complex process. If the same laser is used for removal, it may easily lead to over-removal, causing ablation of the conductive layer, or incomplete removal, causing leakage risk or short circuit risk. The texture structure 123 has a depth of less than 0.1 μm, indicating a shallow depth. This results in a poor effect on the confinement, adhesion, or pull-out force of the conductive layer. Therefore, in this application, the depth of the texture structure 123 is within the aforementioned range. When using the same laser for waste removal, not only is thorough waste removal ensured, but transitional ablation is also avoided. Moreover, the waste removal process only requires the same laser, making the process simpler. At the same time, the effect of improving the confinement, adhesion, or pull-out force of the conductive layer is also taken into account. Furthermore, the depth H1 of the texture structure can be from 1 μm to 5 μm, further improving the confinement of the conductive layer and enhancing the adhesion or pull-out force.

[0104] For example, the depth of the texture structure can be 0.1μm, 0.3μm, 0.5μm, 0.9μm, 1μm, 1.2μm, 1.5μm, 2μm, 2.1μm, 2.5μm, 2.8μm, 3μm, 3.3μm, 3.5μm, 4μm, 4.5μm, or 5μm.

[0105] It should be noted that in the process of determining or counting the number of texture structures in this application, if the conductive layer surface extends along the second direction and at least one of the length, width, and depth in the one-dimensional dimension is within the corresponding numerical range mentioned above, it is considered a texture structure of this application; otherwise, it is not considered a texture structure of this application.

[0106] In some embodiments, the spacing d4 between adjacent texture structures is 0.1 μm to 1000 μm in the direction perpendicular to the extension direction of the texture structure 123. If the spacing d4 between adjacent texture structures 123 is less than 0.1 μm, it indicates that the texture structure 123 is too dense, which may have adverse effects on the continuous waste removal success rate and leakage risk. If the spacing d4 between adjacent texture structures 123 is greater than 1000 μm, it indicates that the texture structure is too sparse. Too sparse a texture structure is not conducive to the confinement of the conductive layer or the promotion of the bonding force or pull-out force between the conductive layer and the surrounding structure. When the ratio of the spacing d4 between adjacent texture structures 123 to the width d3 of the insulation gap 122 is within the above range, it takes into account the continuous waste removal success rate, leakage risk, and the improvement of bonding force or pull-out force, resulting in a higher continuous waste removal success rate, a lower leakage risk in the photovoltaic module, a better confinement effect on the conductive layer 12, a better current collection effect, and better stability and reliability of the photovoltaic module.

[0107] Furthermore, the spacing d4 between adjacent texture structures 123 can be 100 to 800 μm, or, further, the spacing d4 between adjacent texture structures 123 can be 300 to 600 μm to further improve the bonding force or pull-out force between the conductive layer and the surrounding structure, while taking into account the success rate of continuous waste removal and a lower risk of leakage or short circuit.

[0108] For example, the distance d4 between adjacent texture structures 123 may be 0.1 μm, 5 μm, 10 μm, 20 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 320 μm, 350 μm, 37 0μm, 380μm, 400μm, 420μm, 450μm, 480μm, 500μm, 510μm, 550μm, 580μm, 600μm, 620μm, 650μm, 700μm, 750μm, 800μm.

[0109] In some embodiments, refer to Figure 9 and Figure 10 The conductive layer 12 includes a substrate layer 124 and an electrical connection layer covering the substrate layer 124 near the back contact cell. The surface of the conductive layer 12 near the back contact cell is a first surface; for example, Figure 9The diagram shown is a schematic representation of the first surface. At least a partial area of ​​this first surface has the substrate layer 124 exposed. This partial area includes at least one gap between adjacent back-contact cells within a cell string, and / or at least one gap between adjacent cell strings in the cell string array. Specifically, the gaps and gaps are offset from the back-contact cells. The substrate layer 124 exposed at these locations typically has better reflectivity than the electrical connection layer. The exposed substrate layer 124 at these locations can act as a reflective strip, reflecting light incident on the gaps and gaps back to the back-contact cells, increasing light utilization and further improving the efficiency of the photovoltaic module. Additionally, the exposed substrate layer 124 can increase the bonding force between the conductive layer and its adjacent structures, such as the insulating layer, further enhancing the containment effect on the conductive layer.

[0110] It should be noted that the electrical connection effect between the electrical connection layer and the conductor 5 is generally better than that between the substrate layer 124 and the conductor 5. By setting the electrical connection layer on the side of the substrate layer 124 close to the back contact cell, the current collection effect can be further improved. The specific materials of the electrical connection layer and the substrate layer 124 are not limited.

[0111] Figure 10 In the spectrum, the location of spectrum 16 mainly refers to the local area on the surface of the conductive layer, or the surface of the electrical connection layer, that is away from the substrate layer 124. Figure 10 In the diagram, the location of spectrum 15 mainly refers to a local area on the surface of the substrate layer 124. For example, EDS (energy dispersive spectroscopy) analysis of the corresponding location in spectrum 15 shows that the main material of the substrate layer 124 can be aluminum, and EDS analysis of the corresponding location in spectrum 16 shows that the main material of the electrical connection layer can be copper. After the substrate layer 124 is exposed, aluminum oxide may form. Alumina typically has a higher reflectivity in the visible light range than copper. Since silicon-based solar cells generally absorb visible light, the exposed substrate layer at locations such as inter-chip and inter-chip gaps can be used as reflective strips to further increase light utilization.

[0112] In some embodiments, refer to Figure 3 , Figure 4 and Figure 9On the first surface, in the region corresponding to a back contact cell, the length d6 of the exposed substrate layer 124 along the extension direction of the texture structure 123, i.e., the second direction L2, is less than or equal to 5% of the length of the back contact cell along the third direction L4. The third direction L4 is different from the first direction L1. For information on the third direction L4 and the first direction L1, please refer to the aforementioned relevant records. To avoid repetition, it will not be repeated here. Specifically, the electrical connection between the exposed substrate layer 124 and the conductor 5 is poor, and the bonding or pull-out force between the exposed substrate layer 124 and the conductor 5 is also poor. In particular, in the area corresponding to the back contact cell, the size of the exposed substrate layer 124 is too large, which will affect the electrical connection and bonding or pull-out force. Therefore, in this application, by controlling that the length d6 of the exposed substrate layer 124 along the extension direction of the texture structure 123, i.e., the second direction L2, in the area corresponding to the back contact cell is less than or equal to 5%, the ratio of the length of the back contact cell along the third direction L4 is reduced to less than or equal to 5%. This is equivalent to reducing the probability or size of the exposed substrate layer 124 being electrically connected to the conductor 5 in the area corresponding to the back contact cell, thereby improving the electrical connection and bonding or pull-out force, improving the current collection effect, and improving the reliability and stability of the photovoltaic module.

[0113] For example, on the first surface, in the region corresponding to a back contact cell, the length of the exposed substrate layer 124 along the extension direction of the texture structure 123, i.e., the second direction L2, can be 5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.5%, 0.1% of the length of the back contact cell along the third direction L4.

[0114] In some embodiments, refer to Figure 3 , Figure 4 and Figure 9 On the first surface, in the region corresponding to a back contact cell, the number of exposed locations of the substrate layer 124 is less than or equal to 10. Specifically, the electrical connection between the exposed substrate layer 124 and the conductor 5 is poor, and the bonding or pull-out force between the exposed substrate layer 124 and the conductor 5 is also poor. In particular, in the region corresponding to the back contact cell, the size of the exposed substrate layer 124 is too large, which affects the electrical connection effect and the bonding or pull-out force. Therefore, in this application, by controlling the number of exposed locations of the substrate layer 124 in the region corresponding to a back contact cell to be within the above-mentioned range, it is equivalent to reducing the probability and size of the exposed substrate layer 124 being electrically connected to the conductor 5 in the region corresponding to the back contact cell, thereby improving the electrical connection effect and the bonding or pull-out force, and improving the current collection effect.

[0115] For example, on the first surface, in the region corresponding to a back contact cell, the number of exposed locations of the substrate layer 124 can be 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1.

[0116] In some embodiments, refer to Figure 3 , Figure 4 and Figure 9 On the first surface, the exposed substrate layer 124 is linearly distributed. The shape of the exposed substrate layer 124 is relatively regular, making it easy to form. The extension direction of the exposed substrate layer is the aforementioned linear extension direction, and the angle between the extension direction of the exposed substrate layer and the extension direction of the texture structure, or the second direction L2, is less than or equal to 5°. Specifically, the exposed substrate layer is not covered by an electrical connection layer. Therefore, the location of the exposed substrate layer is equivalent to reducing the thickness of the conductive layer, reducing the difficulty of laser waste removal. Thus, its extension direction is roughly parallel to the extension direction of the main body of the insulating gap, reducing waste wire residue, reducing the risk of short circuits or leakage, and improving the success rate of continuous waste removal.

[0117] For example, the angle between the extension direction of the exposed substrate layer 124 and the extension direction of the texture structure, or the second direction L2, can be 5°, 4.5°, 4.1°, 4°, 3.7°, 3.5°, 3.2°, 3°, 2.8°, 2.5°, 2°, 1.6°, 1.5°, 1°, 0.8°, or 0.5°. As another example, the extension direction of the exposed substrate layer 124 can be parallel to the extension direction of the texture structure, or the second direction L2.

[0118] It should be noted that, in Figure 9 In this case, the extension direction of the exposed substrate layer 124 can be parallel to the direction of length d6.

[0119] In some embodiments, the angle between the extending direction of the exposed substrate layer 124 and the extending direction of the main body is less than or equal to 20°. Specifically, the exposed substrate layer is not covered by an electrical connection layer. Therefore, the location of the exposed substrate layer is equivalent to reducing the thickness of the conductive layer, reducing the difficulty of laser waste removal. Thus, its extending direction is approximately parallel to the extending direction of the main body of the insulating gap, reducing waste wire residue, reducing the risk of short circuits or leakage, and improving the success rate of continuous waste removal.

[0120] For example, the angle between the extension direction of the exposed substrate layer 124 and the extension direction L3 of the main body can be 20°, 18°, 15°, 10°, 8°, 6°, 5°, 5°, 4.5°, 4.1°, 4°, 3.7°, 3.5°, 3.2°, 3°, 2.8°, 2.5°, 2°, 1.6°, 1.5°, 1°, 0.8°, or 0.5°. As another example, the extension direction of the exposed substrate layer 124 can be parallel to the extension direction L3 of the main body.

[0121] In some embodiments, on the first surface, the exposed substrate layer 124 and the texture structure 123 at least partially overlap, and the depth of the texture structure 123 at the overlapping location is greater than or equal to 0.5 μm. Specifically, if the depth of the texture structure is greater than or equal to 0.5 μm, the laser energy required for the texture structure 123 differs significantly from the laser energy required for other locations on the conductive layer 12. To achieve the same removal rate, it may be necessary to change the laser power, otherwise it may easily lead to over-ablation or incomplete removal, resulting in a complex process. If the same laser is used for removal, it may easily lead to over-removal, causing ablation of the conductive layer, or incomplete removal, causing leakage or short circuit risks. Therefore, in this application, for locations where the depth of the texture structure is greater than or equal to 0.5 μm, by overlapping the exposed substrate layer 124 with the texture structure at that location, the depth of the texture structure is appropriately reduced. Thus, when the same laser is used for removal, not only is thorough removal guaranteed, but also transitional ablation is avoided. Moreover, the removal process only requires the same laser, making the process simpler. It should be noted that the texture structure 123 here can be a protrusion structure protruding from the conductive layer and adjacent to it, etc.

[0122] In some embodiments, refer to Figure 3 and Figure 4 The back contact cell also includes an interconnect portion 23 electrically connected to the current collector grid lines. The interconnect portion 23 is continuously or intermittently arranged along a third direction L4, which is different from the first direction. For details regarding the interconnect portion 23, please refer to the aforementioned descriptions; to avoid repetition, they will not be repeated here. At least one interconnect portion 23's projection on the first surface avoids the exposed substrate layer 124. Specifically, as mentioned earlier, the electrical connection between the exposed substrate layer 124 and the conductor 5 is poor, and the bonding or pull-out force between the exposed substrate layer 124 and the conductor 5 is also poor. Therefore, in this application, by controlling the projection of the interconnect portion 23 on the first surface to avoid the exposed substrate layer 124, the probability and size of the exposed substrate layer 124 electrically connecting to the conductor 5 in the corresponding area of ​​the back contact cell are reduced, thereby improving the electrical connection effect and bonding or pull-out force, and improving the current collection effect.

[0123] It should be noted that the projection of at least one interconnect portion 23 on the first surface mentioned in this application that avoids the exposed substrate layer 124 can refer to at least one of the following structures: end line 233, first electrode disk 231, second electrode disk 232, first main gate 234 and second main gate 235. The projection of at least one of these structures on the first surface of the conductive layer 12 avoids the exposed substrate layer, and all of these are within the protection scope of this application.

[0124] In some embodiments, refer to Figure 9 and Figure 10 The substrate layer 124 has a textured structure on its surface. Within a unit area, the number of textured structures on the surface of the substrate layer 124 is greater than or equal to the number of textured structures on the surface of the conductive layer. Therefore, by utilizing the textured structure of the substrate layer 124 and taking advantage of certain conformal properties of the process, a conductive layer with a textured surface can be easily fabricated. The unit area here can be 1×1μm, 10×10μm, 10×5μm, 100×100μm, 1000×1000μm, etc., and this application does not limit this.

[0125] It should be noted that although the process of forming an electrical connection layer on the substrate layer has a certain degree of conformability, some of the textured structures on the surface of the substrate layer 124 may be flattened during the formation of the electrical connection layer. Therefore, the number of textured structures on the surface of the substrate layer 124 is greater than or equal to the number of textured structures on the surface of the conductive layer. This results in a conductive layer with a textured surface, which conforms to common conformability characteristics and is a simple process. For example, electroplating or other processes can be used to form the aforementioned electrical connection layer on the surface of a substrate layer with a textured structure.

[0126] Similarly, in the process of counting the number of texture structures on the surface of substrate layer 124, texture structure 123 can only be counted if the depth of the texture structure on the surface of substrate layer 124 is greater than or equal to 0.1μm.

[0127] In some embodiments, the shape of the texture structure on the surface of the substrate layer 124 is similar to the shape of the texture structure on the first surface of the aforementioned conductive layer near the back contact cell, thus conforming to common process conformity characteristics. The aforementioned electrical connection layer can be easily prepared mainly through process conformity characteristics, and the process is simple.

[0128] In some embodiments, the size of the texture structure on the surface of the substrate layer 124 is greater than or equal to the size of the texture structure on the first surface of the aforementioned conductive layer near the back contact cell, thereby conforming to common process conformity characteristics. The aforementioned electrical connection layer can be easily prepared mainly through process conformity characteristics, and the process is simple.

[0129] It should be noted that the difference between the size of the texture structure on the surface of the substrate layer 124 and the size of the texture structure on the first surface of the conductive layer near the back contact cell is based on the conformability of different processes, and is based on the appropriate preparation of the conductive layer surface with the aforementioned size requirements.

[0130] This application also provides a conductive backplate, as shown in the reference. Figure 2 The conductive backsheet 1 includes an insulating layer 11, a conductive layer 12, and a backsheet 14 stacked sequentially. Insulating gaps 122 are formed on the conductive layer 12, dividing it into multiple conductive sheets 121. Each insulating gap 122 includes several main portions 1221 extending generally along a second direction L2 and connecting portions 1222 connecting adjacent main portions 1221. The surface of the conductive layer 12 is provided with several textured structures 123 extending along the second direction L2. The angle α between the extending direction L3 of the main portions 1221 and the second direction L2 is less than or equal to 20°. This conductive backsheet has the same or similar beneficial effects as the aforementioned photovoltaic module; to avoid repetition, it will not be described further here.

[0131] It should be noted that the aforementioned content regarding the conductive layer in photovoltaic modules also applies to the conductive layer in the conductive backsheet. To avoid repetition, it will not be repeated here.

[0132] In this application, each embodiment can be implemented independently, or in combination without contradiction, and all are within the protection scope of this application.

[0133] The following specific examples will further explain this application.

[0134] Example 1 Reference Figure 7 The conductive layer has insulating gaps that divide it into multiple conductive sheets. Each insulating gap includes several main portions extending generally along a second direction and connecting portions connecting adjacent main portions. The surface of the conductive layer has a textured structure extending along the second direction. The extension direction of the main portions is parallel to the extension direction of the textured structure or the second direction, i.e., the average value of the aforementioned included angle α is 0°.

[0135] Yield testing was conducted on 1000 conductive layers from 1000 photovoltaic modules, and the yield result was approximately 99%. Here, yield refers to the ratio of the number of photovoltaic modules with a short-circuit probability of 0 within three months of continuous operation of the module, where the interconnect portion at the through-hole of the conductive sheet completely covers the insulating layer, to the number of modules with a short circuit probability of 0. This yield can reflect, to some extent, the success rate of continuous waste removal and the amount of residual burrs during the formation of the insulation gap. Specifically, a higher yield indicates more precise waste removal positions or insulation gap positions, resulting in a higher success rate of continuous waste removal and fewer residual burrs during the insulation gap formation process. The orthographic projection here refers to the projection of the interconnect portion at the through-hole of the insulating layer onto the first surface of the conductive layer near the back contact cell when illuminated by light parallel to the thickness direction of the photovoltaic module. The determination methods for projections or orthographic projections mentioned elsewhere in this application are similar and will not be repeated here to avoid repetition.

[0136] Example 2 The angle α between the extension direction of the main body and the extension direction of the texture structure or the second direction is 10°. Under the same conditions as in Example 1, the yield of 1000 conductive layers in 1000 photovoltaic modules was tested, and the yield result was approximately 98.5%.

[0137] The rest of Example 2 is the same as Example 1, and will not be repeated here to avoid repetition.

[0138] Example 3 The angle α between the extension direction of the main body and the extension direction of the texture structure or the second direction is 20°. Under the same conditions as in Example 1, the yield of 1000 conductive layers in 1000 photovoltaic modules was tested, and the yield result was approximately 98%.

[0139] The rest of Example 3 is the same as Example 1, and will not be repeated here to avoid repetition.

[0140] Comparative Example 1 The angle α between the extension direction of the main body and the extension direction of the texture structure or the second direction is 30°. Under the same conditions as in Example 1, the yield of 1000 conductive layers in 1000 photovoltaic modules was tested, and the yield result was approximately 94%.

[0141] The rest of Comparative Example 1 is the same as Example 1, and will not be repeated here to avoid repetition.

[0142] Comparative Example 2 The angle α between the extension direction of the main body and the extension direction of the texture structure or the second direction is 45°. Under the same conditions as in Example 1, the yield of 1000 conductive layers in 1000 photovoltaic modules was tested, and the yield result was approximately 90%.

[0143] The rest of Comparative Example 2 is the same as Example 1, and will not be repeated here to avoid repetition.

[0144] Comparative Example 3 The angle α between the extension direction of the main body and the extension direction of the texture structure or the second direction is 60°. Under the same conditions as in Example 1, the yield of 1000 conductive layers in 1000 photovoltaic modules was tested, and the yield result was approximately 80%.

[0145] The rest of Comparative Example 3 is the same as Example 1, and will not be repeated here to avoid repetition.

[0146] Comparative Example 4 The angle α between the extension direction of the main body and the extension direction of the texture structure or the second direction is 90°. Under the same conditions as in Example 1, the yield of 1000 conductive layers in 1000 photovoltaic modules was tested, and the yield result was approximately 80%.

[0147] The rest of Comparative Example 4 is the same as Example 1, and will not be repeated here to avoid repetition.

[0148] Based on the correspondence between the included angle α and the yield of the conductive layer obtained from Examples 1 to 3 and Comparative Examples 1 to 4, a curve showing the correspondence between the yield of the conductive layer and the included angle α is plotted. Figure 12 As shown. Figure 12 The horizontal axis represents the included angle α, in degrees, and the vertical axis represents the yield rate, in 100%. Refer to Examples 1 to 3, Comparative Examples 1 to 4, and... Figure 12 It can be concluded that as the included angle α increases, the yield of the conductive layer generally decreases. When the included angle α is less than or equal to 20°, the yield of the conductive layer is relatively high, meeting practical application requirements. When the included angle α is greater than 20°, the yield of the conductive layer decreases rapidly. Furthermore, when the included angle α is greater than or equal to 60°, the yield of the conductive layer remains roughly unchanged, while when the included angle α is greater than 20°, the conductive layer struggles to meet practical application requirements. Therefore, in this application, the included angle α is set to be less than or equal to 20°, resulting in a higher yield of the conductive layer that meets practical application requirements.

[0149] 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.

[0150] 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.

[0151] 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 photovoltaic module, characterized in that, include: A battery string array, an insulating layer, a conductive layer, and a backplate are stacked in sequence. The battery string array includes: a plurality of battery strings arranged in an array; the battery string includes a plurality of back contact battery cells; the back contact battery cells include: a plurality of current collector grid lines extending along a first direction; The conductive layer has insulating gaps that divide the conductive layer into multiple conductive sheets. Each insulating gap includes a plurality of main body portions extending generally along a second direction and connecting portions connecting adjacent main body portions. The first direction is different from the second direction. The surface of the conductive layer is provided with a plurality of textured structures extending along the second direction; the angle α between the extension direction of the main body and the second direction is less than or equal to 20°.

2. The photovoltaic module according to claim 1, characterized in that, The shape of the texture structure includes straight lines.

3. The photovoltaic module according to claim 1, characterized in that, The number of texture structures intersecting with one of the first main body portions is a first number, and the number of texture structures intersecting with one of the first connecting portions is a second number, the second number being greater than the first number; the first main body portion is connected to the first connecting portion, and both are adjacent to the same conductive sheet.

4. The photovoltaic module according to claim 3, characterized in that, The ratio of the second quantity to the first quantity is less than or equal to 4.

5. The photovoltaic module according to claim 1, characterized in that, The number of texture structures intersecting with one of the main body portions is less than or equal to 100.

6. The photovoltaic module according to claim 1, characterized in that, The connecting part is arc-shaped, and the central angle b corresponding to the connecting part is less than 180°.

7. The photovoltaic module according to claim 3, characterized in that, The connecting part is arc-shaped, and the diameter of the connecting part is smaller than the length of the main body in the extending direction of the main body.

8. The photovoltaic module according to claim 1, characterized in that, The back contact solar cell further includes: an interconnect portion electrically connected to the current collector grid line, the interconnect portion being continuously or discontinuously arranged along a third direction, the third direction being different from the first direction; at least one of the interconnect portions projecting onto the conductive layer covering at least a portion of the texture structure; and / or At least a portion of the insulating layer corresponding to the conductive sheet has through holes, and a conductor is disposed in the through holes. The projection of at least one of the conductors on the conductive layer covers at least a portion of the texture structure.

9. The photovoltaic module according to claim 8, characterized in that, The number of texture structures covered by the projection of one of the interconnects onto the conductive layer is greater than or equal to 1; and / or, The number of texture structures covered by the projection of one of the conductors on the conductive layer is greater than or equal to 1.

10. The photovoltaic module according to claim 1, characterized in that, The extension direction of the main body located between adjacent battery strings is a fourth direction, and the angle between the second direction and the fourth direction is less than or equal to 10°.

11. The photovoltaic module according to claim 1, characterized in that, In the thickness direction of the photovoltaic module, the ratio of the depth of the texture structure to the thickness of the conductive layer is less than or equal to 25%.

12. The photovoltaic module according to claim 1, characterized in that, The ratio of the width d1 of the texture structure to the width d2 of the conductive sheet is less than or equal to 2%. The direction of the width d1 of the texture structure is perpendicular to the second direction, and the direction of the width d2 of the conductive sheet is perpendicular to the third direction, which is different from the first direction.

13. The photovoltaic module according to claim 1, characterized in that, The ratio of the width d1 of the texture structure to the width d3 of the insulation gap is less than or equal to 50%. The direction of the width d1 of the texture structure is perpendicular to the second direction, and the direction of the width d3 of the insulation gap is perpendicular to the extension direction of the insulation gap.

14. The photovoltaic module according to claim 1, characterized in that, The ratio of the spacing d4 between adjacent texture structures to the width d2 of the conductive sheet is less than or equal to 20%. The direction of the spacing d4 between adjacent texture structures is perpendicular to the second direction. The direction of the width d2 of the conductive sheet is perpendicular to a third direction, which is different from the first direction.

15. The photovoltaic module according to claim 1, characterized in that, The ratio of the spacing d4 between adjacent texture structures to the width d3 of the insulation gap is less than or equal to 80%, the direction of the spacing between adjacent texture structures is perpendicular to the second direction, and the direction of the width d3 of the insulation gap is perpendicular to the extension direction of the insulation gap.

16. The photovoltaic module according to claim 1, characterized in that, The width d3 of the insulating gap is n times the spacing d4 between adjacent texture structures, where n is an integer greater than or equal to 1.

17. The photovoltaic module according to claim 1, characterized in that, In a direction perpendicular to the second direction, the width d1 of the texture structure is from 0.1 μm to 100 μm; and / or, Along the second direction, the length d5 ​​of the texture structure is from 1 mm to 250 mm; and / or, In the thickness direction of the photovoltaic module, the depth of the textured structure is 0.1 μm to 5 μm; and / or, In a direction perpendicular to the second direction, the spacing d4 between adjacent texture structures is 0.1 μm to 1000 μm.

18. The photovoltaic module according to claim 1, characterized in that, In a direction perpendicular to the second direction, the width d1 of the texture structure is 10 μm to 50 μm; and / or, In the thickness direction of the photovoltaic module, the depth of the textured structure is 1 μm to 5 μm; and / or, In a direction perpendicular to the second direction, the spacing d4 between adjacent texture structures is 100 μm to 800 μm.

19. The photovoltaic module according to claim 1, characterized in that, The conductive layer includes a substrate layer and an electrical connection layer covering the substrate layer on the side near the back contact cell. The surface of the conductive layer near the back contact cell is the first surface; The substrate layer is exposed in at least a partial area of ​​the first surface; the at least partial area includes: at least one gap between adjacent back-contact cells within the battery string, and / or, at least one gap between adjacent battery strings in the battery string array.

20. The photovoltaic module according to claim 19, characterized in that, On the first surface, in the region corresponding to one of the back contact cells, the length of the exposed substrate layer along the second direction is less than or equal to 5% of the length of the back contact cell along a third direction; the third direction is different from the first direction.

21. The photovoltaic module according to claim 19, characterized in that, On the first surface, in the region corresponding to one of the back contact cells, the number of exposed substrate layers is less than or equal to 10.

22. The photovoltaic module according to claim 19, characterized in that, On the first surface, the exposed substrate layer is linearly distributed, and the angle between the extension direction of the exposed substrate layer and the second direction is less than or equal to 5°; and / or, The angle between the extension direction of the exposed substrate layer and the extension direction of the main body is less than or equal to 20°.

23. The photovoltaic module according to claim 19, characterized in that, On the first surface, the exposed substrate layer and the texture structure at least partially overlap, and the depth of the texture structure at the overlapping location is greater than or equal to 0.5 μm.

24. The photovoltaic module according to claim 19, characterized in that, The back contact cell further includes: an interconnection portion electrically connected to the current collector grid line, the interconnection portion being continuously or discontinuously arranged along a third direction, the third direction being different from the first direction; at least one of the interconnection portions projecting onto the first surface avoids the exposed substrate layer.

25. The photovoltaic module according to claim 19, characterized in that, The substrate layer surface has a textured structure, and within a unit area: the number of textured structures on the substrate layer surface is greater than or equal to the number of textured structures on the conductive layer surface; and / or, The shape of the texture structure on the surface of the substrate layer is similar to the shape of the texture structure on the first surface; and / or, The size of the texture structure on the surface of the substrate layer is greater than or equal to the size of the texture structure on the first surface.

26. A conductive backplate, characterized in that, Includes: an insulating layer, a conductive layer, and a backing plate stacked sequentially; An insulating gap is formed on the conductive layer to divide the conductive layer into multiple conductive sheets. The insulating gap includes a plurality of main body portions extending generally along the second direction and a connecting portion connecting adjacent main body portions. The surface of the conductive layer is provided with a plurality of textured structures extending along the second direction; the angle α between the extension direction of the main body and the second direction is less than or equal to 20°.

27. The conductive backplate according to claim 26, characterized in that, In a direction perpendicular to the second direction, the width d1 of the texture structure is from 0.1 μm to 100 μm; and / or, Along the second direction, the length d5 ​​of the texture structure is from 1 mm to 250 mm; and / or, In the thickness direction of the conductive backplate, the depth of the textured structure is 0.1 μm to 5 μm; and / or, In a direction perpendicular to the second direction, the spacing d4 between adjacent texture structures is 0.1 μm to 1000 μm.

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