Gap adhesive film and photovoltaic module

Abstract

The embodiment of the present application provides a gap adhesive film and a photovoltaic module, the gap adhesive film is used for filling the gap around the cell in the photovoltaic module, the gap adhesive film comprises at least one supporting color layer and at least one adhesive layer, the melt index of the supporting color layer is less than or equal to 2 g / 10 min at a temperature of 150 DEG C, and the reflectivity of the supporting color layer in a wavelength range of 200-1800 nm is 30%-98%; the adhesive layer is attached to at least one side of the supporting color layer; the gap adhesive film is basically in a strip shape, the thickness of the gap adhesive film ranges from 0.1 mm to 0.5 mm, and the width of the gap adhesive film ranges from 1 mm to 30 mm. When the photovoltaic module is packaged, the gap adhesive film is arranged around the cell, can provide a supporting force, avoids appearance problems such as glue overflow and bubbles in the packaging process, can also avoid the problems of cell cracking or hidden cracking, meanwhile, the cost is low when the gap adhesive film and the application thereof are used, obvious power gain can be brought to the module, and the cost performance is high.

Description

Technical Field

[0001] This application relates to the field of photovoltaic encapsulation film technology, and in particular to a gap sealant film and a photovoltaic module. Background Technology

[0002] In the lamination process of photovoltaic modules, the encapsulating film is an essential component, and its flowability plays a crucial role in the encapsulation effect. Photovoltaic modules have a complex structure, composed of solar cells and various auxiliary materials. Therefore, the pressure experienced by the module during lamination is not uniform, with the highest tendency for encapsulating film flow at the gaps between the cells. Consequently, defects such as excess adhesive, bubbles, and wrinkles are mostly concentrated around the perimeter of the module and between the cells. Using high molecular weight or multi-branched EVA or POE masterbatch as the substrate for the encapsulating film, or employing complex additive systems and pre-crosslinking processes to restrict the flow of the encapsulating film, will significantly increase the overall complexity of the process and lead to a substantial increase in the cost of the encapsulating film. Utility Model Content

[0003] To address the aforementioned issues, this application provides a gap sealant film that can be used in conjunction with traditional encapsulation films to reduce undesirable appearance around photovoltaic modules and between cells, while also improving the utilization rate of sunlight through the gaps.

[0004] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0005] One aspect of this application provides a gap sealant film for filling the gaps around the cells in a photovoltaic module. The gap sealant film includes at least one supporting color layer and at least one adhesive layer. The supporting color layer has a melt index of less than or equal to 2 g / 10 min at 150°C and a reflectance of 30%-98% in the wavelength range of 200-1800 nm. The adhesive layer is adhered to at least one side of the supporting color layer. The thickness of the gap sealant film ranges from 0.1 mm to 0.5 mm, and the width of the gap sealant film ranges from 1 mm to 30 mm.

[0006] Furthermore, the supporting color layer is one of black, white, or a colored layer.

[0007] Furthermore, the supporting color layer is a composite film composed of one or more of the following: PE film, EVA cross-linked film, PET film, and PP film.

[0008] Furthermore, the adhesive layer is one of an EVA film, a POE film, or an EPE film.

[0009] Furthermore, the gap film includes at least two supporting color layers, which are arranged adjacent to each other.

[0010] Furthermore, the gap film consists of two stacked support color layers and an adhesive layer disposed on one side of the support color layers.

[0011] Furthermore, the gap film consists of a supporting color layer and two adhesive layers located on both sides of the supporting color layer.

[0012] Furthermore, the gap film consists of a support color layer and an adhesive layer stacked together.

[0013] Another aspect of this application embodiment provides a photovoltaic module, which includes a front substrate, a front encapsulant film, a cell string layer, a back encapsulant film, a back substrate, and the aforementioned gap encapsulant film stacked sequentially; the back substrate includes a cell region corresponding to the cell in the cell string layer and a gap region other than the cell region, the gap encapsulant film fills the gap region, and the adhesive layer of the gap encapsulant film is attached to the back substrate.

[0014] Furthermore, the gap region includes a first gap region corresponding to the gap between the cells in the battery string layer and a second gap region corresponding to the gap between the battery strings in the battery string layer and the gap between the battery string and the edge of the back substrate. The gap adhesive film includes a first gap adhesive film filling the first gap region and a second gap adhesive film filling the second gap region. The width of the first gap adhesive film ranges from 1 mm to 5 mm, and the width of the second gap adhesive film ranges from 5 mm to 30 mm.

[0015] This application provides a strip-shaped gap film with low flowability and high reflectivity. When photovoltaic modules are encapsulated, the gap film is placed around the cells to provide support and prevent appearance problems such as glue overflow and bubbles during the encapsulation process. It can also prevent cell cracking or microcracks. At the same time, the gap film and its application have low cost and provide significant power gain to the module, making it highly cost-effective. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the first type of gap film provided in the embodiments of this application;

[0017] Figure 2 This is a schematic diagram of the structure of the second type of gap film provided in the embodiments of this application;

[0018] Figure 3 This is a schematic diagram of the structure of the third type of gap film provided in the embodiments of this application;

[0019] Figure 4 This is a schematic diagram of a photovoltaic module provided in an embodiment of this application;

[0020] Figure 5 This is a regional distribution diagram of the back substrate in a photovoltaic module provided in an embodiment of this application;

[0021] Figure 6 This is a schematic diagram of the structure of the photovoltaic module after the back substrate and the gap film are combined in an embodiment of this application.

[0022] In the figure: gap film 100, support color layer 11, adhesive layer 12, photovoltaic module 200, front substrate 21, front film 22, cell string layer 23, back film 24, back substrate 25, cell area 251, gap area 252, first gap area 2521, second gap area 2522. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0024] This application provides a spacer film 100 for filling around the cells in a photovoltaic module 200. For example... Figure 1 As shown, the gap sealant 100 includes at least one supporting color layer 11 and at least one adhesive layer 12, with the adhesive layer 12 attached to at least one side of the supporting color layer 11. The supporting color layer 11 in the gap sealant 100 primarily serves to enhance reflection and provide support, while the adhesive layer 12 primarily serves to bond the gap sealant 100 to the back substrate 25 of the photovoltaic module 200 or other components within the photovoltaic module 200, ensuring reliable adhesion stability between the gap sealant 100 and the back substrate 25 or other components within the photovoltaic module 200.

[0025] The supporting color layer 11 can increase the reflectivity of light irradiated onto the gap film 100, thereby improving the overall power of the photovoltaic module 200. The supporting color layer 11 also has the characteristics of small deformation under high temperature and high pressure, which can provide better support during the encapsulation of the photovoltaic module 200, maintain stability during lamination, and avoid appearance problems caused by the low pressure bearing capacity of the film at the gap of the cells.

[0026] The melt flow index of the supporting color layer 11 at 150°C is less than or equal to 2 g / 10 min. Even under the high temperature and high pressure environment of the photovoltaic module 200 encapsulation process, the melt flow index of the supporting layer in the gap film 100 remains within a small range, and the supporting color layer 11 has low fluidity. During the photovoltaic module 200 encapsulation process, it can prevent appearance problems such as glue overflow and bubbles caused by excessive film fluidity at the gaps between cells and around the edges.

[0027] The reflectivity of the supporting color layer 11 is 30%-98% in the wavelength range of 200-1800nm. The supporting color layer 11 has a high light reflectivity, which can reflect the unused light in the photovoltaic module 200 back to the solar cells for photoelectric conversion again, thereby increasing the overall power of the photovoltaic module 200 and improving the overall light utilization rate of the photovoltaic module 200.

[0028] The gap sealant 100 is generally strip-shaped, with a thickness ranging from 0.1mm to 0.5mm and a width ranging from 1mm to 30mm. This strip-shaped gap sealant 100 better adapts to the gaps between solar cells and the space between the solar cells and the edges of the photovoltaic module 200, meeting the placement requirements of the gap sealant 100 in the appropriate positions. No additional cutting is required during use, reducing the difficulty of use and improving efficiency. The thickness and width of the gap sealant 100 within the aforementioned ranges give it wider adaptability, making it applicable to virtually all photovoltaic modules 200.

[0029] As an optional implementation, the support color layer in the gap film has a color. The color of the support color layer 11 is one of black, white, or a colored layer. Specifically, the color of the support color layer can be white, black, black / white, blue, red, brown, purple, green, or yellow. While meeting the light reflectance requirements of the support color layer 11, the color of the support color layer 11 can be selected according to actual needs. For example, black can be selected to make the photovoltaic module 200 more uniform in color with the roof or other structures it is installed on. White can also be selected to give the support color layer 11 higher light reflectance, while also making the color scheme of the photovoltaic module 200 more harmonious and aesthetically pleasing. A colored layer can also be selected to enrich the color of the photovoltaic module 200, and even to create corresponding colored patterns through design.

[0030] As an optional implementation, the supporting color layer 11 is a PE film layer. The PE film itself has relatively low fluidity, which can fill the space around the solar cell during the encapsulation process of the photovoltaic module 200, and at the same time maintain a stable state during the encapsulation process, without causing appearance defects such as glue overflow or bubbles.

[0031] As an optional implementation, the adhesive layer 12 is one of an EVA film, a POE film, or an EPE film. The adhesive layer 12 can be selected as a film with good adhesion performance. The adhesive layer 12 works in conjunction with the supporting color layer 11 to improve the bonding ability between the gap sealant film 100 and the back substrate 25 in the photovoltaic module 200, preventing the gap sealant film 100 from slipping during the photovoltaic module 200 encapsulation process, and also preventing the gap sealant film 100 from peeling or falling off during the use of the photovoltaic module 200.

[0032] As an optional implementation method, such as Figure 2 As shown, the gap film 100 includes at least two supporting color layers 11, which are arranged adjacent to each other. Multiple supporting color layers 11 can be provided in the gap film 100. Firstly, the interface between the supporting color layers 11 can be used to improve light reflectivity. Secondly, supporting color layers 11 with different properties can also achieve additional functions. For example, a white supporting color layer 11 that can improve light reflectivity and a black or colored supporting color layer 11 that meets appearance color requirements can simultaneously satisfy both light reflection and appearance requirements.

[0033] To further illustrate the structure of the gap film 100 in the embodiments of this application, three specific structures of the gap film 100 are provided as examples.

[0034] The first type of spacer film 100 Figure 1 As shown, the gap film 100 is composed of a supporting color layer 11 and an adhesive layer 12 stacked sequentially. The supporting color layer 11 serves to support and improve light reflectivity, while the adhesive layer 12 serves to firmly bond the supporting color layer 11 to the back substrate 25 of the photovoltaic module 200. Furthermore, the color of the supporting color layer 11 can be selected as white, black, or colored to meet corresponding usage or appearance requirements.

[0035] The second type of gap film 100 Figure 2 As shown, the gap film 100 is composed of two supporting color layers 11 and an adhesive layer 12. The two supporting color layers 11 are stacked, and the adhesive layer 12 is disposed on one side of the laminate formed by the two supporting color layers 11. The two supporting color layers 11 can be identical or different. Identical supporting color layers 11 can enhance light reflectivity through their interface. Different supporting color layers 11 can have a certain color difference; the inner supporting color layer 11 (the one closer to the adhesive layer 12) can be white, while the outer supporting color layer 11 (the one farther from the adhesive layer 12) can be black or colored. The inner supporting color layer 11 enhances the overall light reflectivity of the gap film 100, while the outer supporting color layer 11 provides a better visual effect. For example, when the outer supporting color layer 11 is black, the color of the gap film 100 can be more unified and coordinated with the color of the surrounding battery cells. If the outer support color layer 11 is colored, it can enrich the color of the photovoltaic module 200 and form a certain colored pattern on the photovoltaic module 200.

[0036] The third type of gap film 100 Figure 3As shown, the gap sealant 100 is composed of an adhesive layer 12, a supporting color layer 11, and another adhesive layer 12 stacked sequentially. Adhesive layers 12 are provided on both sides of the supporting color layer 11, allowing the gap sealant 100 to simultaneously adhere to both the front substrate 21 and the rear substrate 25, thus improving the adhesion stability of the gap sealant 100 in the photovoltaic module 200. Furthermore, the color of the supporting color layer 11 can be selected as white, black, or colored to meet corresponding usage or appearance requirements.

[0037] The three gap films 100 described above are merely illustrative examples of the gap films 100 in this application embodiment, and do not represent an exhaustive list of all possible gap film 100 structures. Based on the three specific gap film structures 100 described above in this application embodiment, gap films 100 with corresponding structures can be obtained within the scope of the technical solutions included in this application embodiment according to actual needs.

[0038] Another aspect of this application provides a photovoltaic module 200, such as... Figure 4 As shown, the photovoltaic module 200 includes a front substrate 21, a front encapsulant film 22, a cell string layer 23, a back encapsulant film 24, a back substrate 25, and the aforementioned gap encapsulant film 100, which are stacked sequentially; Figure 5 As shown, the back substrate 25 includes a battery region 251 corresponding to the battery cells in the battery string layer 23 and a gap region 252 other than the battery region. A gap adhesive film 100 fills the gap region 252, and the adhesive layer 12 of the gap adhesive film 100 is attached to the back substrate 25.

[0039] In the photovoltaic module 200, a gap film 100 is provided in the gap area 252 around the solar cell. This can solve the appearance defects such as glue overflow and bubbles caused by insufficient support in the gap area 252 around the solar cell during the encapsulation process of the photovoltaic module 200. At the same time, the gap film 100 can also play a supporting role during the encapsulation process of the photovoltaic module 200, preventing defects such as microcracks in the solar cell.

[0040] As an optional implementation method, such as Figure 5 and Figure 6 As shown, the gap region 252 includes a first gap region 2521 corresponding to the gap between the battery cells in the battery string layer 23. Figure 5 The narrower gap region) and the second gap region 2522 (corresponding to the gap between battery strings in the battery string layer 23 and the gap between the battery string and the edge of the back substrate 25) Figure 5The gap film 100 includes a first gap film 100 filling the first gap region 2521 and a second gap film 100 filling the second gap region 2522. The width of the first gap film 100 ranges from 1 mm to 5 mm, and the width of the second gap film 100 ranges from 5 mm to 30 mm. Gap films 100 of appropriate sizes are set for different specific regions within the gap region 252. Since the width of the first gap between battery cells within the same battery string is relatively small, using a first gap film 100 with a width range of 1 mm to 5 mm can meet the needs of most first gaps, while also avoiding the problem of battery cell compression caused by an excessively wide first gap film 100. The width of the second gap between the battery strings and between the battery strings and the edge of the back substrate 25 is relatively large. Using a second gap adhesive film 100 with a width range of 5mm to 30mm can meet the requirements of the largest second gap. At the same time, it can avoid the problem of squeezing the battery strings due to the excessive width of the second gap adhesive film 100 and the problem of the edge of the second gap adhesive film 100 exceeding the edge of the back substrate 25.

[0041] Finally, it should be noted that the above are only some preferred embodiments of this application and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A gap filler film for filling the gaps around solar cells in a photovoltaic module, characterized in that, The gap membrane includes: At least one supporting color layer, wherein the supporting color layer has a melt index of less than or equal to 2 g / 10 min at a temperature of 150°C and a reflectance of 30%-98% in the wavelength range of 200-1800 nm; and at least one adhesive layer, wherein the adhesive layer is adhered to at least one side of the supporting color layer. The thickness of the gap membrane ranges from 0.1 mm to 0.5 mm, and the width of the gap membrane ranges from 1 mm to 30 mm.

2. The gap film according to claim 1, characterized in that: The supporting color layer is one of black, white, or a colored layer.

3. The gap film according to claim 1, characterized in that: The supporting color layer is a composite material film composed of one or more of the following: PE film, EVA cross-linked film, PET film, and PP film.

4. The gap film according to claim 1, characterized in that: The adhesive layer is one of EVA film, POE film or EPE film.

5. The gap film according to claim 1, characterized in that: The gap film includes at least two supporting color layers, which are arranged adjacent to each other.

6. The gap film according to claim 1, characterized in that: The gap film consists of two stacked support color layers and an adhesive layer disposed on one side of the support color layers.

7. The gap film according to claim 1, characterized in that: The gap film consists of a supporting color layer and two adhesive layers located on both sides of the supporting color layer.

8. The gap film according to claim 1, characterized in that: The gap film consists of a support color layer and an adhesive layer stacked together.

9. A photovoltaic module, characterized in that: The photovoltaic module includes a front substrate, a front encapsulant film, a battery string layer, a rear encapsulant film, a rear substrate, and a gap encapsulant film as described in any one of claims 1 to 8, which are stacked in sequence. The back substrate includes a battery region corresponding to the battery cells in the battery string layer and a gap region other than the battery region. The gap adhesive film fills the gap region, and the adhesive layer of the gap adhesive film is attached to the back substrate.

10. The photovoltaic module according to claim 9, characterized in that: The gap region includes a first gap region corresponding to the gap between the battery cells in the battery string layer and a second gap region corresponding to the gap between the battery strings in the battery string layer and the gap between the battery string and the edge of the back substrate. The gap adhesive film includes a first gap adhesive film filling the first gap region and a second gap adhesive film filling the second gap region. The width of the first gap adhesive film ranges from 1 mm to 5 mm, and the width of the second gap adhesive film ranges from 5 mm to 30 mm.

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