Black conductive gap film and photovoltaic module

Abstract

This utility model relates to the field of photovoltaic technology, and more particularly to a black conductive gap film and a photovoltaic module. The black conductive gap film includes a substrate layer, an adhesive layer, a black material layer, and a conductive reflective layer. The black material layer and the conductive reflective layer are respectively disposed on opposite sides of the substrate layer. The adhesive layer is disposed on the side of the black material layer facing away from the substrate layer, and is used to bond to the gap between two adjacent solar cells. The conductive reflective layer is used to contact and electrically conduct with the solder strips of the same polarity in the cell string, and also to reflect light onto the solar cells. This black conductive gap film not only blocks the solder strips at the gaps between solar cells, but also reduces current mismatch in the cell string, thereby improving the electrical performance of the photovoltaic module.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic technology, and in particular to a black conductive gap film and a photovoltaic module. Background Technology

[0002] Currently, photovoltaic (PV) technology, as a core component of clean energy, is continuously evolving towards higher efficiency, higher reliability, and diversified applications. Back-contact (BC) PV modules, by arranging both positive and negative electrodes on the back of the cell, eliminate shading losses from the front-side metal grid lines, significantly improving photoelectric conversion efficiency and becoming an important development direction in the PV field. Among them, all-black BC PV modules, through the use of black backsheets, special coatings, and other materials or processes, achieve a black appearance on the back and even the entire module. This not only maintains the high-efficiency power generation characteristics of BC technology but also meets the aesthetic design requirements of building-integrated photovoltaics (BIPV), showing broad application prospects in PV building curtain walls, roof integration, and other scenarios.

[0003] In existing all-black BC photovoltaic modules, the function of the black film strip is limited to blocking the silver solder strip. In all-black BC photovoltaic modules, the current between cells can only be transmitted through a single path of the solder strip. When there are problems such as poor contact or uneven resistance of the solder strip, it is easy to cause current mismatch in the cell string, resulting in a decrease in the overall electrical performance of the photovoltaic module.

[0004] Therefore, there is an urgent need to design a black conductive gap film and photovoltaic module to solve the above technical problems. Utility Model Content

[0005] The purpose of this invention is to propose a black conductive gap film and a photovoltaic module, which can not only shield the solder strips at the gaps between the cells, but also reduce the phenomenon of current mismatch in the cell string and improve the electrical performance of the photovoltaic module.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] On the one hand, this utility model provides a black conductive gap film, comprising:

[0008] A base layer, wherein a black material layer and a conductive reflective layer are respectively disposed on opposite sides of the base layer;

[0009] An adhesive layer is disposed on the side of the black material layer opposite to the substrate layer, and the adhesive layer is used to bond to the gap between two adjacent battery cells.

[0010] The conductive reflective layer is used to contact and electrically conduct with the solder strips of the same polarity in the battery string, and the conductive reflective layer is used to reflect light onto the battery cell.

[0011] As an alternative technical solution for a black conductive gap film, the black conductive gap film further includes a resin layer, one side of which is bonded to the substrate layer, and the conductive reflective layer is formed on the side of the resin layer opposite to the substrate layer.

[0012] As an alternative technical solution for a black conductive gap film, the conductive reflective layer is a metal layer.

[0013] As an optional technical solution for a black conductive gap film, the conductive reflective layer is one of an aluminum-plated reflective layer, a silver-plated reflective layer, a copper-plated reflective layer, or an indium tin oxide reflective layer.

[0014] As an alternative technical solution for a black conductive gap film, the adhesive layer is an EVA layer, the black material layer is a carbon black layer, and the base layer is a PET layer.

[0015] On the other hand, this utility model provides a photovoltaic module, which includes a plurality of solar cells, a first solder strip, a second solder strip, and a black conductive gap film as described in any of the above optional technical solutions; the plurality of solar cells are arranged in a preset pattern, the black conductive gap film is disposed at the gap between two adjacent solar cells, one of the first solder strip and the second solder strip is disposed on the solar cell and in contact with the black conductive gap film, and the other of the first solder strip and the second solder strip is disposed on the solar cell and maintains a preset distance L from the black conductive gap film, wherein the first solder strip and the second solder strip have different polarities.

[0016] As an optional technical solution for photovoltaic modules, three adjacent solar cells are defined as solar cell A, solar cell B, and solar cell C; two adjacent black conductive gap films are defined as black conductive gap film a and black conductive gap film b.

[0017] The black conductive gap film a is disposed at the gap between the battery cell A and the battery cell B, and the black conductive gap film b is disposed at the gap between the battery cell B and the battery cell C; the first solder strip is disposed on the battery cell A and the battery cell B, the first solder strip is in contact with the black conductive gap film a and is electrically conductive, and the end of the first solder strip is kept at a preset distance L from the black conductive gap film b; the second solder strip is disposed on the battery cell B and the battery cell C, the second solder strip is in contact with the black conductive gap film b and is electrically conductive, and the end of the second solder strip is kept at a preset distance L from the black conductive gap film a.

[0018] As an optional technical solution for photovoltaic modules, both the first solder strip and the second solder strip are configured in multiples, with the multiple first solder strips arranged at equal intervals along a first direction, the multiple second solder strips arranged at equal intervals along the first direction, and the first solder strip and the second solder strip are alternately arranged along the first direction.

[0019] As an optional technical solution for photovoltaic modules, the preset distance L is set between 2mm and 8mm.

[0020] As an optional technical solution for photovoltaic modules, the photovoltaic module includes a front encapsulant film, a back encapsulant film, a front glass, and a black backsheet. The first solder ribbon, the second solder ribbon, the black conductive gap film, and a plurality of solar cells form a cell string. The front encapsulant film is applied to the front side of the cell string, the front glass is disposed on the front encapsulant film, the back encapsulant film is applied to the back side of the cell string, and the black backsheet is disposed on the back encapsulant film.

[0021] The beneficial effects of this utility model include at least the following:

[0022] This invention provides a black conductive gap film disposed at the gap between two adjacent solar cells. The black conductive gap film includes a substrate layer, an adhesive layer, a black material layer, and a conductive reflective layer. The black material layer and the conductive reflective layer are respectively disposed on opposite sides of the substrate layer. The adhesive layer is disposed on the side of the black material layer facing away from the substrate layer and is used to bond to the gap between two adjacent solar cells. The conductive reflective layer is used to contact and electrically conduct with the solder strips of the same polarity in the solar cell string, and also to reflect light onto the solar cells.

[0023] As described above, a black material layer and a conductive reflective layer are respectively disposed on both sides of the base layer of the black conductive gap film, and the adhesive layer is located outside the black material layer for bonding with the gap between the solar cells. This design allows the black conductive gap film to both shield the solder ribbons between the cells and provide conductive and reflective functions. The conductive reflective layer allows it to contact and conduct electricity with solder ribbons of the same polarity, increasing the current transmission path (rather than relying solely on the solder ribbons). When there is poor contact or uneven resistance in the solder ribbons, the conductive reflective layer can shunt the current, reducing series mismatch in the solar cell strings and improving the electrical performance of the photovoltaic module. Furthermore, the conductive reflective layer reflects scattered light from the gaps between the cells back to the solar cells, improving light utilization, increasing power generation, and enhancing the photoelectric conversion efficiency of the photovoltaic module. In addition, the black material layer shields the solder ribbons between the solar cells, ensuring the all-black appearance of the photovoltaic module and meeting the aesthetic requirements of BIPPV.

[0024] This utility model also provides a photovoltaic module that can not only shield the solder strips at the gaps between the cells, but also reduce the phenomenon of current mismatch in the cell string and improve the electrical performance of the photovoltaic module. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this utility model and these drawings without creative effort.

[0026] Figure 1 This is a cross-sectional view of the black conductive gap film provided in an embodiment of this utility model;

[0027] Figure 2 This is a top view of the battery string provided in an embodiment of the present utility model;

[0028] Figure 3 This is a cross-sectional view of the battery string provided in an embodiment of this utility model;

[0029] Figure 4 This is a cross-sectional view of the photovoltaic module provided in this embodiment of the present invention.

[0030] Figure Labels

[0031] 10. Base layer; 20. Black material layer; 30. Conductive reflective layer; 40. Adhesive layer; 50. Resin layer; 60. Black conductive gap film a; 70. Black conductive gap film b;

[0032] 100, First welding strip; 200, Second welding strip; 300, Cell A; 400, Cell B; 500, Cell C; 600, Front adhesive film; 700, Back adhesive film; 800, Front glass; 900, Black backplate; 1000, Battery string. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0035] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0036] In the description of this utility model, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0037] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" 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. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0038] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0039] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown 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 utility model, and should not be construed as limiting this utility model.

[0040] This embodiment provides a black conductive gap film and a photovoltaic module, which can not only shield the solder strips at the gaps between the cells, but also reduce the phenomenon of current mismatch in the cell string and improve the electrical performance of the photovoltaic module.

[0041] like Figures 1-4 As shown, the black conductive gap film is disposed at the gap between two adjacent solar cells. The black conductive gap film mainly includes a substrate layer 10, an adhesive layer 40, a black material layer 20, and a conductive reflective layer 30. The black material layer 20 and the conductive reflective layer 30 are respectively disposed on opposite sides of the substrate layer 10. The adhesive layer 40 is disposed on the side of the black material layer 20 facing away from the substrate layer 10, and is used to bond to the gap between two adjacent solar cells. The conductive reflective layer 30 is used to contact and electrically conduct with the solder strips of the same polarity in the battery string 1000, and also reflects light onto the solar cells.

[0042] Based on the above design, in this embodiment, a black material layer 20 and a conductive reflective layer 30 are respectively disposed on both sides of the base layer 10 of the black conductive gap film, and the adhesive layer 40 is located outside the black material layer 20 for bonding with the gap between the solar cells. This design allows the black conductive gap film to both shield the solder ribbons between the cells and provide conductive and reflective functions. The conductive reflective layer 30 can, on the one hand, contact and conduct electricity with solder ribbons of the same polarity, increasing the current transmission path (instead of relying solely on the solder ribbons). When there is poor contact or uneven resistance of the solder ribbons, the current can be diverted through the conductive reflective layer 30, reducing the series mismatch phenomenon of the 1000 cell strings and improving the electrical performance of the photovoltaic module. On the other hand, the conductive reflective layer 30 has a reflective function, which can reflect the scattered light at the gap between the cells back to the solar cells, improving light utilization, increasing power generation, and improving the photoelectric conversion efficiency of the photovoltaic module.

[0043] In addition, the black material layer 20 can cover the solder strips between the cells, ensuring the all-black appearance of the photovoltaic module and meeting the aesthetic requirements of BIPV.

[0044] like Figure 1 As shown, in this embodiment, the black conductive gap film further includes a resin layer 50, one side of which is bonded to the substrate layer 10, and a conductive reflective layer 30 is formed on the side of the resin layer 50 facing away from the substrate layer 10.

[0045] After adding the resin layer 50, the conductive reflective layer 30 is formed on the surface of the resin layer 50, which improves the bonding force and stability between the conductive reflective layer 30 and the substrate layer 10, ensures that the conductive reflective layer 30 is not easily detached or damaged during use, and extends the service life of the black conductive gap film.

[0046] For example, the resin layer 50 is made of acrylic resin with a thickness of 10μm-30μm. After being coated on the surface of the substrate layer 10, the adhesion to the substrate layer 10 is enhanced by drying and curing, providing a smooth substrate for the conductive reflective layer 30.

[0047] In some alternative embodiments, the conductive reflective layer 30 is a metal layer. For example, the conductive reflective layer 30 is one of an aluminum-plated reflective layer, a silver-plated reflective layer, a copper-plated reflective layer, or an indium tin oxide reflective layer.

[0048] For example, the conductive reflective layer 30 in this embodiment is an aluminum-plated reflective layer, prepared by magnetron sputtering, with a thickness set at 150nm-250nm. Aluminum's high reflectivity and low cost make it a cost-effective choice. Simultaneously, the aluminum layer possesses certain corrosion resistance, adapting to the long-term outdoor use environment of photovoltaic modules, providing a stable path for current transmission, and reducing current mismatch. Of course, operators can flexibly select conductive reflective layers 30 of different materials according to the actual needs and application scenarios of the photovoltaic modules; these will not be elaborated upon here.

[0049] In some optional embodiments, the adhesive layer 40 is an EVA layer. EVA material has good adhesion and light transmittance, ensuring that the black conductive gap film is firmly bonded to the gaps between the solar cells, while not affecting light transmission to the solar cells, thus guaranteeing the optical performance of the photovoltaic module. The black material layer 20 is a carbon black layer. Carbon black provides excellent light-shielding performance, effectively blocking the silver solder ribbon, meeting the all-black appearance design requirements of the photovoltaic module. Furthermore, carbon black has high stability and is not easily faded, ensuring the consistency and aesthetics of the photovoltaic module's appearance during long-term use. The base layer 10 is a PET layer. PET material has good mechanical properties, chemical stability, and dimensional stability, providing a solid foundation for the black conductive gap film and ensuring its structural integrity during the production and use of the photovoltaic module.

[0050] For example, in this embodiment, the adhesive layer 40 can be set to 100μm-200μm, the black material layer 20 can be set to 20μm-40μm, the base layer 10 can be set to 100μm-300μm, and the resin layer 50 can be set to 10μm-30μm.

[0051] The fabrication process of the black conductive gap film in this embodiment is as follows:

[0052] Preparation of substrate layer 10: PET film is selected as substrate layer 10, with a thickness generally between 50-150μm to ensure good mechanical strength and flexibility. The PET film is cleaned to remove surface dust, oil, and other impurities to ensure the adhesion of subsequent coatings.

[0053] Preparation of Black Material Layer 20: Carbon black or black oxide is mixed with polyurethane or acrylic resin, and an appropriate amount of antioxidant is added to form a uniform coating. The black coating is uniformly applied to one side of a PET film using a spray or roller coating process, controlling the coating thickness to be 10μm-50μm. The PET film coated with the black coating is placed in a drying oven and dried at 80-120℃ for 10-30 minutes to cure the black material layer 20, forming a dense and uniform coating.

[0054] Resin layer 50 coating: Prepare an acrylic resin solution or slurry, ensuring good flowability and coating performance. Using a spray or roller coating process, uniformly coat the acrylic resin onto the other side of the PET film (the side opposite to the black material layer 20), controlling the coating thickness to 10μm-30μm. Dry the acrylic resin-coated PET film at 60-100℃ for 5-15 minutes to cure the resin layer 50, forming a smooth and even surface.

[0055] Preparation of conductive reflective layer 30: A high-reflectivity metal material, such as aluminum, silver, or copper, is selected. A metal layer is deposited on the surface of the acrylic resin layer 50 using magnetron sputtering or evaporation to form the conductive reflective layer 30, with a thickness controlled between 50 nm and 500 nm. The conductive reflective layer 30 is ensured to be uniform and continuous, without obvious pinholes or defects.

[0056] Preparation of adhesive layer 40: Ethylene-vinyl acetate copolymer (EVA) is mixed with a crosslinking agent to form a uniform adhesive solution. The EVA adhesive solution is uniformly coated on the side of the black material layer 20 facing away from the PET film, ensuring uniform coating without bubbles or voids. The black material layer 20 coated with EVA adhesive solution is heat-cured at 80-120℃ for 10-30 minutes to form adhesive layer 40, with a thickness of 50μm-200μm.

[0057] like Figures 2-4 As shown, this embodiment also provides a photovoltaic module, which mainly includes multiple solar cells, a first solder ribbon 100, a second solder ribbon 200, and the aforementioned black conductive gap film; the multiple solar cells are arranged according to a preset pattern, the black conductive gap film is disposed at the gap between two adjacent solar cells, one of the first solder ribbon 100 and the second solder ribbon 200 is disposed on the solar cell and in contact with the black conductive gap film, and the other of the first solder ribbon 100 and the second solder ribbon 200 is disposed on the solar cell and maintains a preset distance L from the black conductive gap film, and the first solder ribbon 100 and the second solder ribbon 200 have different polarities.

[0058] By connecting the same polarity solder strips (such as the first solder strip 100) to the black conductive gap film, the current transmission path is increased. When the resistance of a certain section of the first solder strip 100 is too high or the contact is poor, the current can be shunted through the black conductive gap film, reducing series mismatch. Meanwhile, the opposite polarity solder strips (such as the second solder strip 200) maintain a preset distance L from the black conductive gap film to prevent short circuits caused by solder strips of different polarities conducting through the black conductive gap film, ensuring the safety of the photovoltaic module. Furthermore, the black conductive gap film covers the silver first solder strip 100 and silver second solder strip 200 at the inter-cell gaps of the solar cells, giving the front of the photovoltaic module an all-black appearance, meeting the requirements of BIPV (Building Integrated Photovoltaics).

[0059] It should be noted that the battery cell in this embodiment is a BC battery cell, with both its positive and negative electrodes arranged on the back of the battery, and no grid lines on the front of the battery.

[0060] In some alternative embodiments, the inter-cell gap can be set to 2mm-4mm. Both the first solder strip 100 and the second solder strip 200 are tin-plated copper solder strips. By controlling the cutting length of the first solder strip 100 and the second solder strip 200, the preset distance L between the end of the opposite polarity solder strip and the black conductive gap film is ensured to be between 2mm and 8mm.

[0061] Specifically, such as Figures 2-3 As shown, three adjacent solar cells are defined as solar cell A300, solar cell B400, and solar cell C500; two adjacent black conductive gap films are defined as black conductive gap film a60 and black conductive gap film b70.

[0062] A black conductive gap film a60 is disposed at the gap between solar cells A300 and B400, and a black conductive gap film b70 is disposed at the gap between solar cells B400 and C500. A first solder ribbon 100 is disposed on solar cells A300 and B400, and the first solder ribbon 100 is in contact with and electrically connected to the black conductive gap film a60. The end of the first solder ribbon 100 is kept at a preset distance L from the black conductive gap film b70. A second solder ribbon 200 is disposed on solar cells B400 and C500, and the second solder ribbon 200 is in contact with and electrically connected to the black conductive gap film b70. The end of the second solder ribbon 200 is kept at a preset distance L from the black conductive gap film a60.

[0063] By limiting the contact between the same polarity solder ribbons and the black conductive gap film at the inter-cell gap of the corresponding solar cell, for example, the first solder ribbon 100 only contacts the black conductive gap film a60 and the second solder ribbon 200 only contacts the black conductive gap film b70, short circuits in the photovoltaic module are avoided. The end of the first solder ribbon 100 maintains a preset distance L from the black conductive gap film b70, and the end of the second solder ribbon 200 maintains a preset distance L from the black conductive gap film a60, further preventing indirect conduction between different black conductive gap films through the solder ribbons, ensuring inter-string electrical isolation, and reducing the risk of short circuits.

[0064] like Figures 2-3 As shown, multiple first solder strips 100 and multiple second solder strips 200 are provided. The multiple first solder strips 100 are arranged at equal intervals along a first direction, and the multiple second solder strips 200 are arranged at equal intervals along the first direction, with the first solder strips 100 and the second solder strips 200 alternating along the first direction. The first direction is... Figure 2 The Y-axis direction is the same as the length direction of the solar cell.

[0065] Multiple first solder strips 100 and multiple second solder strips 200 are arranged at equal intervals along the same direction, increasing the current collection points and making the current generated by the battery cell more uniformly collected. The first solder strips 100 and the second solder strips 200 are alternately arranged along the first direction, which can match the layout of the positive and negative grid lines on the back of the battery cell, ensuring effective contact between the solder strips of the same polarity and the black conductive gap film, and maximizing the current shunting effect;

[0066] For example, multiple first solder strips 100 are arranged at equal intervals of 8mm in the same direction, and multiple second solder strips 200 are arranged at equal intervals of 8mm in the same direction, which can reduce local resistance differences, reduce the risk of hot spots, and improve the reliability of photovoltaic modules.

[0067] like Figure 4 As shown, the photovoltaic module also includes a front encapsulant film 600, a back encapsulant film 700, a front glass 800, and a black backsheet 900. A first solder ribbon 100, a second solder ribbon 200, a black conductive gap film, and multiple solar cells form a cell string 1000. The cell string 1000 extends along a second direction perpendicular to the first direction. The second direction is... Figure 2 The X-axis direction is shown. The front adhesive film 600 is applied to the front of the battery string 1000, the front glass 800 is placed on the front adhesive film 600, the back adhesive film 700 is applied to the back of the battery string 1000, and the black back plate 900 is placed on the back adhesive film 700.

[0068] The front encapsulant film 600 and the front glass 800 protect the cell strings 1000 from environmental factors, improving the module's weather resistance and mechanical strength. The back encapsulant film 700 and the black backsheet 900 not only provide physical protection, but also work together with the black conductive gap film to achieve an all-black appearance of the module, enhancing the overall aesthetics of the photovoltaic module to meet the aesthetic requirements of BIPV.

[0069] The front glass 800 ensures efficient transmission of incident light to the solar cells, while the conductive reflective layer 30 of the black conductive gap film reflects scattered light back to the solar cells, improving the light absorption efficiency of the solar cells. The black back sheet 900 further blocks light leakage, ensuring that there is no light scattering loss on the back of the photovoltaic module, thereby improving the photoelectric conversion efficiency of the photovoltaic module.

[0070] The front adhesive film 600 is made of EVA or POE material with a thickness of 300μm-500μm, ensuring good adhesion to the front glass 800 and the battery string 1000, while providing excellent optical performance and weather resistance, allowing light to be efficiently transmitted to the battery cells and protecting the battery string 1000 from moisture and ultraviolet radiation.

[0071] The back film 700 is made of PVDF or EVA material with a thickness of 200μm-400μm. It is tightly bonded to the back of the black backplate 900 and the battery string 1000, providing good insulation and weather resistance, protecting the back electrodes of the battery string 1000 and preventing moisture intrusion and electrode corrosion.

[0072] The front glass of the 800 uses 3.2mm thick low-iron tempered glass with a light transmittance of over 95%. The surface is coated to further enhance the light transmittance, while also possessing good mechanical strength and weather resistance, and can withstand environmental tests such as wind pressure, snow pressure and hail impact.

[0073] The Black Backplate 900 uses a composite backplate with a fluorine-containing film, which has high resistance to ultraviolet aging.

[0074] It is understandable that anti-reflective coatings (such as multilayer films of silicon nitride and silicon oxide) are typically fabricated on the front side (light-receiving side) of solar cells. Besides reducing light reflection to improve light absorption efficiency, all-black photovoltaic modules adjust the thickness and refractive index of the anti-reflective coating to reduce the reflectivity of the anti-reflective coating to extremely low levels (typically <5%), while also slightly absorbing specific wavelengths of light to give the front a deep black hue (rather than the blue or dark blue of traditional solar cells). Since the back side of the photovoltaic module in this embodiment is covered and shielded by a black backsheet 900, the back electrodes of the solar cells and the grid lines on the back of the cell surface do not require additional blackening processes.

[0075] The manufacturing process of the photovoltaic module (black BC photovoltaic module) in this embodiment is as follows:

[0076] Cell arrangement: Arrange the BC cells on the string welding machine welding platform according to the designed cell spacing (2mm-8mm) to ensure accurate positioning.

[0077] Cutting and pasting of black conductive gap film: The cutting machine cuts the black conductive gap film to the required length (matching the gap between cells) according to the width of the cell; the suction cup transfers the cut black conductive gap film to the gap between two adjacent cells, and the welding platform heats (90℃-150℃) to make the adhesive layer of the black conductive gap film adhere and fix to the back of the cell.

[0078] Battery string 1000 fabrication: First and second solder ribbons 100 and 200, cut to size, are laid onto the electrodes of the battery string 1000, ensuring that solder ribbons of the same polarity are in contact with the conductive reflective layer 30 of the black conductive gap film; solder ribbons of different polarities must maintain a preset distance L of 2mm-8mm from the black conductive gap film to avoid short-circuit risks. Electrical connections of the battery string 1000 are completed using interconnection technologies such as high-temperature welding (150-200℃), film coating, and adhesive dispensing, forming a continuous current path.

[0079] Photovoltaic module stacking: A front film 600 is laid on the front glass 800; the cell strings 1000 are arranged on the front film 600 according to the design pattern, and the busbars are welded using a stacking welding machine. Then, a back film 700 and a black back sheet 900 are laid in sequence to cover the back of the cell strings 1000, ensuring that the gaps between the cell strings 1000 are blocked by the black back sheet 900.

[0080] Lamination process: The stacked photovoltaic modules are placed in a laminator and laminated for 15-20 minutes at 135℃-150℃ and 0.1MPa-0.2MPa pressure to ensure that the materials of each layer are tightly bonded, and finally a black BC photovoltaic module is formed.

[0081] Obviously, the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Many other equivalent embodiments may be included without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

[0082] Note that in the description of this specification, the references to terms such as "some embodiments," "other embodiments," 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 utility model. 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.

Claims

1. A black conductive gap film characterized in that, include: A base layer (10) is provided with a black material layer (20) and a conductive reflective layer (30) on opposite sides of the base layer (10); An adhesive layer (40) is disposed on the side of the black material layer (20) away from the base layer (10), and the adhesive layer (40) is used to bond to the gap between two adjacent battery cells. The conductive reflective layer (30) is used to contact and electrically conduct with the solder strips of the same polarity in the battery string (1000), and the conductive reflective layer (30) is used to reflect light onto the battery cell.

2. The black conductive gap film according to claim 1, characterized in that, The black conductive gap film also includes a resin layer (50), one side of which is bonded to the substrate layer (10), and the conductive reflective layer (30) is formed on the side of the resin layer (50) away from the substrate layer (10).

3. The black conductive gap film according to claim 1, characterized in that, The conductive reflective layer (30) is a metal layer.

4. The black conductive gap film according to claim 3, characterized in that, The conductive reflective layer (30) is one of the following: aluminum-plated reflective layer, silver-plated reflective layer, copper-plated reflective layer, and indium tin oxide reflective layer.

5. The black conductive gap film according to claim 1, characterized in that, The adhesive layer (40) is an EVA layer, the black material layer (20) is a carbon black layer, and the base layer (10) is a PET layer.

6. A photovoltaic module, characterized in that, The photovoltaic module includes multiple solar cells, a first solder strip (100), a second solder strip (200), and a black conductive gap film according to any one of claims 1-5; the multiple solar cells are arranged in a preset pattern, the black conductive gap film is disposed at the gap between two adjacent solar cells, one of the first solder strip (100) and the second solder strip (200) is disposed on the solar cell and in contact with the black conductive gap film, the other of the first solder strip (100) and the second solder strip (200) is disposed on the solar cell and maintains a preset distance L from the black conductive gap film, and the first solder strip (100) and the second solder strip (200) have different polarities.

7. The photovoltaic module according to claim 6, characterized in that, The three adjacent battery cells are defined as battery cell A (300), battery cell B (400) and battery cell C (500); the two adjacent black conductive gap films are defined as black conductive gap film a (60) and black conductive gap film b (70); The black conductive gap film a (60) is disposed at the gap between the battery cell A (300) and the battery cell B (400), and the black conductive gap film b (70) is disposed at the gap between the battery cell B (400) and the battery cell C (500); the first solder ribbon (100) is disposed on the battery cell A (300) and the battery cell B (400), the first solder ribbon (100) is in contact with the black conductive gap film a (60) and electrically connected, and the end of the first solder ribbon (100) is kept at a preset distance L from the black conductive gap film b (70); the second solder ribbon (200) is disposed on the battery cell B (400) and the battery cell C (500), the second solder ribbon (200) is in contact with the black conductive gap film b (70) and electrically connected, and the end of the second solder ribbon (200) is kept at a preset distance L from the black conductive gap film a (60).

8. The photovoltaic module according to claim 7, characterized in that, The first solder strip (100) and the second solder strip (200) are both provided in multiples. The multiple first solder strips (100) are arranged at equal intervals along the first direction, and the multiple second solder strips (200) are arranged at equal intervals along the first direction. The first solder strips (100) and the second solder strips (200) are alternately arranged along the first direction.

9. The photovoltaic module according to claim 7, characterized in that, The preset distance L is set between 2mm and 8mm.

10. The photovoltaic module according to any one of claims 6-9, characterized in that, The photovoltaic module includes a front encapsulant film (600), a back encapsulant film (700), a front glass (800), and a black backsheet (900). The first solder ribbon (100), the second solder ribbon (200), the black conductive gap film, and a plurality of the solar cells form a cell string (1000). The front encapsulant film (600) is applied to the front side of the cell string (1000), the front glass (800) is disposed on the front encapsulant film (600), the back encapsulant film (700) is applied to the back side of the cell string (1000), and the black backsheet (900) is disposed on the back encapsulant film (700).

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