Reflective film, photovoltaic laminate, photovoltaic module and photovoltaic device

Abstract

The utility model relates to the technical field of photovoltaic equipment, and provides a reflective film, a photovoltaic laminated piece, a photovoltaic assembly and a photovoltaic device, and the reflective film comprises a first bonding layer, a substrate layer, a structural layer, a reflective layer and a second bonding layer which are arranged in sequence; the first bonding layer is suitable for being bonded with a back plate of the photovoltaic module; and the second bonding layer is suitable for corresponding to the position of a gap region which is not covered by the battery piece in the photovoltaic module and is used for supplementing glue to the gap region. According to the arrangement, during lamination, the second bonding layer of the reflective film can be pointedly filled into the gap area, the problem that bubbles are generated during lamination due to insufficient glue amount in the gap area when a low-gram-weight glue film is adopted is effectively avoided, and meanwhile, the reflective film can enable light entering the gap area to be finally reflected to a battery piece, so that the irradiation amount is increased, and the reliability of the battery piece is improved. Compared with the prior art, the method can effectively solve the problem that different cost-reducing and efficiency-increasing means are difficult to combine and apply due to compatibility, thereby further realizing cost-reducing and efficiency-increasing.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of photovoltaic equipment, especially to a light reflection film, photovoltaic laminated piece, photovoltaic module and photovoltaic device. BACKGROUND

[0002] In recent years, with the growth of global demand for renewable energy and the increasing concern about environmental problems, photovoltaic technology, as an important part of renewable clean energy, has achieved rapid development. In order to reduce production cost, improve conversion efficiency, and thus achieve higher economic and social benefits, cost reduction and efficiency increase have become the consistent development main line of the photovoltaic industry.

[0003] At present, the commonly used cost reduction and efficiency increase means includes 0BB technology, light reflection film technology and low grammage adhesive film technology; among them, 0BB technology cancels the main grid line, reduces the shading area of the front of the cell piece, improves the light absorption rate, and reduces the use amount of silver and other precious metals; and the light reflection film technology is to reflect the light not absorbed by the front surface back to the cell surface, increase the secondary utilization of light, and thus improve the overall photoelectric conversion efficiency; the low grammage adhesive film technology reduces the cost by reducing the grammage of the front and back adhesive films.

[0004] However, when different cost reduction and efficiency increase means are combined and applied, there may be a problem of incompatibility between different technologies, for example, when 0BB photovoltaic module is matched with low grammage adhesive film, in order to ensure the amount of adhesive at the gap, the light reflection film cannot be pasted. Therefore, how to achieve further cost reduction and efficiency increase has become an important issue to be solved at present. UTILITY MODEL CONTENTS

[0005] The utility model provides a light reflection film, photovoltaic laminated piece, photovoltaic module and photovoltaic device to solve the problem that further cost reduction and efficiency increase cannot be achieved in the prior art, which can effectively solve the problem that different cost reduction and efficiency increase means cannot be combined and applied due to compatibility, thereby achieving further cost reduction and efficiency increase.

[0006] The utility model provides a light reflection film, which comprises:

[0007] A first adhesive layer, a substrate layer, a structure layer, a light reflection layer and a second adhesive layer are sequentially arranged;

[0008] The first adhesive layer is suitable for being bonded with the back plate of the photovoltaic module;

[0009] The second adhesive layer is suitable for corresponding to the gap area position not covered by the cell piece in the photovoltaic module, and is used to supplement the amount of adhesive to the gap area.

[0010] According to the light reflection film provided by the utility model, the grammage of the second adhesive layer is not less than 100g / m 2 .

[0011] The utility model also provides a photovoltaic laminated piece, including back plate, back adhesive film, cell layer, front adhesive film and front plate which are arranged in sequence;

[0012] It also includes the above-mentioned reflective film;The first adhesive layer of the reflective film is bonded with the back plate;The second adhesive layer of the reflective film corresponds to the gap area position of the cell layer which is not covered by the cell piece.

[0013] According to the photovoltaic laminated piece provided by the utility model, the cell layer includes a plurality of cell strings arranged in an array, and the cell string is a 0BB cell string.

[0014] According to the photovoltaic laminated piece provided by the utility model, the gap area includes a first gap area formed between cell pieces in the cell string;

[0015] The reflective film includes a sheet film strip, and the sheet film strip corresponds to the position of the first gap area.

[0016] According to the photovoltaic laminated piece provided by the utility model, the gap area includes a second gap area formed between different groups of cell strings;

[0017] The reflective film includes a string film strip, and the string film strip corresponds to the position of the second gap area.

[0018] According to the photovoltaic laminated piece provided by the utility model, the gap area includes a third gap area formed around the cell layer;

[0019] The reflective film includes a peripheral film strip, and the peripheral film strip corresponds to the position of the third gap area.

[0020] According to the photovoltaic laminated piece provided by the utility model, the grammage of the front adhesive film and the back adhesive film is not greater than 160g / m 2 .

[0021] The utility model also provides a photovoltaic assembly, including frame, junction box and above-mentioned photovoltaic laminated piece;

[0022] The photovoltaic laminated piece is packaged in the frame, and the junction box is electrically connected with the photovoltaic laminated piece.

[0023] The utility model also provides a photovoltaic device, including above-mentioned reflective film or above-mentioned photovoltaic laminated piece or above-mentioned photovoltaic assembly.

[0024] Beneficial effects:

[0025] The light reflection film, the photovoltaic laminated piece, the photovoltaic assembly and the photovoltaic device provided by the utility model can be used for effectively solving the problem that different cost-reducing and benefit-increasing means cannot be combined and applied due to compatibility, thereby further realizing cost reduction and benefit increase.

[0026] Two, the 0BB battery string can greatly reduce the use amount of silver paste on one hand, and can increase the effective light exposure area of the battery piece on the other hand, improve the power generation efficiency of the photovoltaic assembly, and the assembly link uses the welding strip to lead out the current, shortens the current transmission distance, and reduces the loss; when the laminated piece is manufactured, the first adhesive layer of the light reflection film is pre-adhered to the back plate, and then the back plate, the back adhesive film, the battery layer, the front adhesive film and the front plate are assembled together through a certain process, the second adhesive layer corresponds to the gap area of the battery layer which is not covered by the battery piece, so that the second adhesive layer can be filled into the gap area in a targeted manner when laminating, and the light reflection film can reflect the light incident to the gap area, increase the irradiance and improve the power. Compared with the related art, the perfect combination of 0BB technology, light reflection film technology and low weight adhesive film technology can be realized, thereby realizing further cost reduction and benefit increase. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the utility model, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0028] Fig. 1 It is the structure schematic view of the light reflection film provided by the utility model embodiment.

[0029] Fig. 2 It is the structure schematic view of the laminated piece provided by the utility model embodiment.

[0030] Fig. 3 It is the structure schematic view of the light reflection film and the back plate provided by the utility model embodiment.

[0031] Reference signs:

[0032] 10. Reflective film; 100. First adhesive layer; 101. Base layer; 102. Structural layer; 103. Reflective layer; 104. Second adhesive layer; 11. Sheet film strip; 12. String film strip; 13. Surrounding film strip; 20. Back panel; 21. Back adhesive film; 22. Battery layer; 23. Front adhesive film; 24. Front panel. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions 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, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0034] To better understand the reflective film, photovoltaic laminate, photovoltaic module and photovoltaic device provided in the embodiments of this utility model, we will first introduce their application background. In order to reduce production costs and improve conversion efficiency, thereby achieving higher economic and social benefits, cost reduction and efficiency improvement has become the consistent development theme of the photovoltaic industry.

[0035] Currently, commonly used cost reduction and efficiency improvement methods include OBB technology, reflective film technology, and low-weight film technology. Among them, OBB technology reduces the light-blocking area on the front of the cell by eliminating the main grid lines, thereby improving the light absorption rate and reducing the amount of precious metals such as silver used. Reflective film technology increases the secondary utilization of light by reflecting light that is not absorbed on the front back to the cell surface, thus improving the overall photoelectric conversion efficiency. Low-weight film technology reduces costs by reducing the weight of the film on both the front and back sides.

[0036] However, when trying to combine different cost reduction and efficiency improvement methods, incompatibility issues between different technologies may arise. For example, when OBB photovoltaic modules are paired with low-weight adhesive films, ensuring sufficient adhesive at the gaps may prevent the reflective film from being properly adhered.

[0037] Generally, photovoltaic modules typically consist of a laminate, which, from top to bottom, comprises front glass, front encapsulant film, cell strings, back encapsulant film, and back glass. When using OBB cell strings with low-weight encapsulant film technology, due to the gaps between the cells in the OBB cell string, and the inherent thickness of the cells and the encapsulant film itself, if a low-weight encapsulant film is desired, encapsulant film must be pre-applied to the back glass at the locations corresponding to the cell gaps to prevent air bubbles from forming during lamination due to insufficient adhesive at these gaps. Under these conditions, it is clearly impossible to install a reflective film. Conversely, if OBB technology is used with a reflective film, a low-weight encapsulant film cannot be combined.

[0038] Incompatibility between technologies makes it difficult to combine different cost reduction and efficiency improvement methods. Therefore, how to further reduce costs and improve efficiency has become an important issue that needs to be addressed.

[0039] To address the aforementioned issues, this utility model provides a reflective film, a photovoltaic laminate, a photovoltaic module, and a photovoltaic device, which can effectively solve the problem of incompatibility between different cost reduction and efficiency improvement methods, thereby achieving further cost reduction and efficiency improvement.

[0040] The following is combined Figs. 1-3 This invention describes the reflective film, photovoltaic laminate, photovoltaic module, and photovoltaic device.

[0041] Reference Figs. 1 to 3 A reflective film 10 includes a first adhesive layer 100, a base layer 101, a structural layer 102, a reflective layer 103, and a second adhesive layer 104 arranged sequentially. The first adhesive layer 100 is suitable for bonding with the backsheet 20 of a photovoltaic module. The second adhesive layer 104 is suitable for corresponding to the gap area in the photovoltaic module that is not covered by the solar cells, and is used to supplement the amount of adhesive to the gap area.

[0042] In practical applications, the various components of a photovoltaic module are assembled according to a specific process. The first adhesive layer 100 of the reflective film 10 is bonded to the backsheet 20 of the photovoltaic module, while the second adhesive layer 104 corresponds to the gap areas in the photovoltaic module not covered by the solar cells. During lamination, the second adhesive layer 104 can specifically fill the gap areas, effectively avoiding the problem of air bubbles caused by insufficient adhesive in the gap areas when using low-weight adhesive films. At the same time, the reflective film 10 is located in the gap areas not covered by the solar cells, enabling the light incident on the gap areas to be ultimately reflected onto the solar cells, thereby increasing the irradiance and improving the power. The reflective film 10 provided by this utility model can effectively solve the problem of the incompatibility between different cost reduction and efficiency improvement methods, thereby achieving further cost reduction and efficiency improvement.

[0043] In one embodiment of this utility model, the first adhesive layer 100 and the second adhesive layer 104 serve as an adhesive. The first adhesive layer 100 is used to adhere the reflective film 10 to the backsheet 20 of the photovoltaic module, and the second adhesive layer 104 is used to fill the gap areas in the battery module that are not covered by the battery cells to avoid air bubbles generated during lamination. The specific materials of the first adhesive layer 100 and the second adhesive layer 104 can be flexibly selected according to actual needs. For example, ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), or co-extruded POE film can be used. No specific limitations are made in this embodiment of the utility model.

[0044] In one embodiment of this invention, the base layer 101 primarily serves a supporting function. It can be made of polyester (PET), polyimide (PI), or other high-strength polymers to ensure sufficient mechanical strength and flexibility. The specific material and thickness of the base layer 101 can be flexibly selected and designed according to actual needs, and no specific limitations are imposed in this embodiment of the invention.

[0045] In one embodiment of this utility model, the structural layer 102 is also referred to as the prism layer, which typically includes multiple triangular prism-shaped microprism structures protruding from the base and arranged in parallel. These structures are mainly used to control the incident and reflection paths of light. Generally, the prism layer is made of UV-curable adhesive. The cured resin is transferred to the surface of the substrate layer by a prism structure roller and then cured by UV light. The UV-curable adhesive can be polyacrylate, polyurethane acrylate, or polyepoxy acrylate, etc., and can be flexibly selected according to actual needs. No specific limitation is made in this embodiment of the utility model. The specific structural form of the structural layer 102 can be referred to the prior art, and will not be described in detail in this embodiment of the utility model.

[0046] In one embodiment of this utility model, the reflective layer 103 is a film layer disposed on the structural layer 102. Specifically, the reflective layer 103 can be a metal layer or a metal oxide layer, such as a silver plating layer, an aluminum plating layer, a TiO2-containing white coating layer, etc. The specific formation method can be physical vapor deposition, chemical vapor deposition, electroplating, electroless plating, etc. The specific material and formation method of the reflective layer 103 can be selected according to actual needs, and no specific limitations are imposed in this embodiment of the utility model.

[0047] In one embodiment of this utility model, in order to ensure the amount of adhesive filling the gap area by the second adhesive layer 104, the basis weight of the second adhesive layer 104 is not less than 100 g / m². 2 .

[0048] The photovoltaic laminate provided by this utility model is described below. The photovoltaic laminate described below can be referred to in correspondence with the reflective film 10 described above.

[0049] Reference Fig. 2 and Fig. 3 A photovoltaic laminate includes a back sheet 20, a back adhesive film 21, a cell layer 22, a front adhesive film 23, and a front panel 24 arranged in sequence; it also includes a reflective film 10 provided in any of the above embodiments; wherein, the first adhesive layer 100 of the reflective film 10 is connected to the back sheet 20, and the second adhesive layer 104 corresponds to the position of the gap area in the cell layer 22 that is not covered by the cell.

[0050] In one embodiment of this invention, the battery layer 22 includes multiple battery strings arranged in an array, and the battery strings are OBB battery strings. OBB technology, also known as gridless technology, eliminates the traditional main grid lines, retaining only fine grid lines. This significantly reduces the amount of silver paste used and increases the effective light-receiving area of ​​the battery cells, improving the power generation efficiency of the photovoltaic module. In the module stage, solder ribbons are used to conduct current, shortening the current transmission distance and reducing losses. In the OBB battery string, a polymer film layer replaces the PAD points of the battery to fix the solder ribbons, and a low-temperature alloy coating is used to lower the welding temperature, allowing the solder ribbons to form an electrical connection with the fine grid lines of the battery cells during the lamination process.

[0051] In one embodiment of this invention, the basis weight of the front adhesive film 23 and the back adhesive film 21 is no greater than 160 g / m². 2 The gap areas not covered by the battery cells in the battery layer 22 are supplemented with adhesive through the second adhesive layer 104 of the reflective film 10.

[0052] Through the above technical solution, the use of OBB battery strings can significantly reduce the amount of silver paste used, while also increasing the effective light-receiving area of ​​the battery cells and improving the power generation efficiency of photovoltaic modules. The current is conducted via solder ribbons in the module assembly, shortening the current transmission distance and reducing losses. During the lamination process, the first adhesive layer 100 of the reflective film 10 is pre-bonded to the backsheet 20. Then, the backsheet 20, back adhesive film 21, battery layer 22, front adhesive film 23, and front panel 24 are assembled together through a specific process. The second adhesive layer 104 corresponds to the gap areas in the battery layer 22 that are not covered by the battery cells, allowing the second adhesive layer 104 to specifically fill these gap areas during lamination. Furthermore, the reflective film 10 can reflect light incident on these gap areas, increasing irradiance and improving power. Compared to related technologies, this solution achieves a perfect combination of OBB technology, reflective film 10 technology, and low-weight adhesive film technology, thereby further reducing costs and increasing efficiency.

[0053] Specifically, the front panel 24 and the back panel 20 are made of glass.

[0054] Specifically, the front adhesive film 23 and the back adhesive film 21 can be made of ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), or co-extruded POE film, etc.

[0055] In one embodiment of this invention, the gap region includes a first gap region formed between the battery cells in the battery string; the reflective film 10 includes film strips 11, which correspond to the position of the first gap region. In practical applications, the film strips 11 are attached between the battery cells, and the specific number of film strips 11 can be adaptively adjusted according to different patterns.

[0056] In one embodiment of this invention, the gap region further includes a second gap region formed between different groups of battery strings; the reflective film 10 includes a strip 12, which corresponds to the position of the second gap region. In practical applications, the strip 12 is attached between the battery strings, and the specific number of strips 12 can also be determined according to the design.

[0057] In one embodiment of this invention, the gap region further includes a third gap region formed around the battery layer 22; the reflective film 10 includes a perimeter film strip 13, the perimeter film strip 13 corresponding to the third gap region. In practical applications, the perimeter film strip 13 is attached to the periphery of the battery layer 22, covering the periphery of the battery layer 22.

[0058] It is understood that, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples.

[0059] On another front, this utility model also provides a photovoltaic module, including a frame, a junction box, and a photovoltaic laminate provided in any of the above embodiments; wherein the photovoltaic laminate is encapsulated in the frame, and the junction box is electrically connected to the photovoltaic laminate, for example, connected to the busbar of the photovoltaic laminate to achieve current output.

[0060] In another aspect, the present invention also provides a photovoltaic device, including the reflective film 10 provided in any of the above embodiments, the laminate provided in any of the above embodiments, or the photovoltaic module described above.

[0061] The reflective film, photovoltaic laminate, photovoltaic module, and photovoltaic device provided by this utility model embodiment allow the second adhesive layer 104 to be specifically filled into the gap area during lamination. This effectively avoids the problem of air bubbles being generated during lamination due to insufficient adhesive in the gap area when using low-weight adhesive film. At the same time, the reflective film 10 is located in the gap area not covered by the solar cell, which enables the light incident on the gap area to be ultimately reflected onto the solar cell, thereby increasing the irradiance and improving the power. This effectively solves the problem of the incompatibility between different cost reduction and efficiency improvement methods, thereby achieving further cost reduction and efficiency improvement.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A reflective film (10), characterized in that, include: The first adhesive layer (100), the base layer (101), the structural layer (102), the reflective layer (103), and the second adhesive layer (104) are sequentially arranged. The first adhesive layer (100) is suitable for bonding with the backsheet (20) of the photovoltaic module; The second adhesive layer (104) is adapted to correspond to the location of the gap area in the photovoltaic module that is not covered by the solar cells, and is used to supplement the amount of adhesive to the gap area.

2. The reflective film (10) according to claim 1, characterized in that, The basis weight of the second adhesive layer (104) is not less than 100 g / m². 2 .

3. A photovoltaic laminate, characterized in that, It includes a back panel (20), a back adhesive film (21), a battery layer (22), a front adhesive film (23), and a front panel (24) arranged in sequence; It also includes a reflective film (10) as described in claim 1 or 2; the first adhesive layer (100) of the reflective film (10) is bonded to the back plate (20); the second adhesive layer (104) of the reflective film (10) corresponds to the position of the gap area in the battery layer (22) that is not covered by the battery cells.

4. The photovoltaic laminate according to claim 3, characterized in that, The battery layer (22) includes multiple battery strings arranged in an array, and the battery strings are OBB battery strings.

5. The photovoltaic laminate according to claim 4, characterized in that, The gap region includes a first gap region formed between the battery cells in the battery string; The reflective film (10) includes a film strip (11) which corresponds to the position of the first gap region.

6. The photovoltaic laminate according to claim 4, characterized in that, The gap region includes a second gap region formed between different groups of the battery strings; The reflective film (10) includes a strip (12) that corresponds to the position of the second gap region.

7. The photovoltaic laminate according to claim 4, characterized in that, The gap region includes a third gap region formed around the battery layer (22); The reflective film (10) includes a four-sided film strip (13), which corresponds to the position of the third gap region.

8. The photovoltaic laminate according to claim 3, characterized in that, The basis weight of the front adhesive film (23) and the back adhesive film (21) is no greater than 160 g / m². 2 .

9. A photovoltaic module, characterized in that, Includes a frame, a junction box, and a photovoltaic laminate as described in any one of claims 3 to 8; The photovoltaic laminate is encapsulated in the frame, and the junction box is electrically connected to the photovoltaic laminate.

10. A photovoltaic device, characterized in that, It includes the reflective film (10) as described in any one of claims 1 to 2, the photovoltaic laminate as described in any one of claims 3 to 8, or the photovoltaic module as described in claim 9.

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