Photovoltaic module

Abstract

The utility model provides a kind of photovoltaic module, comprising: front plate;Power generation layer is located in the side of front plate;Metal backboard is located in the side of power generation layer away from front plate, metal backboard is connected with front plate, the side of metal backboard close to power generation layer is provided with recess.The utility model provides a kind of photovoltaic module, by recess is set in the side surface of metal backboard and front plate connection, utilize recess to form the stress guide area and flexible hinge of prearranged on rigid metal backboard surface, so that the adhesive interface between encapsulating material and front plate and metal backboard can keep stable, reduce bubble production and the condition of interface completely separates, reduce the risk of water vapor and air intrusion, to significantly improve the long-term reliability of photovoltaic module structure, effectively delay component aging, avoid permanent damage to power generation performance.

Description

Technical Field

[0001] This utility model relates to the field of building-integrated photovoltaics (BIPV) technology, and more specifically, to a photovoltaic module. Background Technology

[0002] Currently, the core structure of widely used metal photovoltaic tiles is a laminated structure of "glass-cell-metal backsheet". While this structure possesses good structural strength and weather resistance, its heavy glass front results in a large overall weight, placing high demands on the load-bearing capacity of the building roof and limiting its widespread application in existing buildings, light steel structure buildings, or load-sensitive scenarios. To address the weight issue of traditional metal photovoltaic tiles, the industry is gradually exploring lightweight technology solutions. One feasible direction is to replace glass with polymer materials as the front panel. For example, high-performance polymer films such as polyethylene terephthalate (PET) can be combined with a metal backsheet to form a composite structure of "polymer front panel-cell-metal backsheet". This structure significantly reduces the product's weight and has promising application prospects. However, this structure has a fundamental technical flaw in practical applications, making it difficult to meet the requirements for long-term reliability and service life. Specifically, there is a significant difference in the linear coefficient of thermal expansion between the polymer front sheet (such as PET) and the metal back sheet. Under the periodic changes in outdoor ambient temperature, this difference causes inconsistent thermal expansion and contraction between the two layers, resulting in huge interlayer shear stress within the module. This long-term, alternating stress leads to two serious reliability problems: 1. Material interface delamination: Stress causes the bonding interface between the encapsulation material and the PET front sheet and metal back sheet to fail, producing bubbles or completely detaching, allowing moisture and air to easily penetrate, accelerating module aging and causing permanent damage to power generation performance. 2. Electrical connection failure: Accumulated stress is transferred to the internal cells and interconnecting solder strips, easily leading to fatigue fracture (detachment) of solder joints or microcracks in the cells, causing open circuits or increased resistance, resulting in module failure. Therefore, while this simple material replacement in related technologies achieves weight reduction, it sacrifices the long-term reliability and service life of the product.

[0003] Therefore, how to design a photovoltaic module that can fundamentally solve the delamination and desoldering problems caused by thermal mismatch while ensuring the advantages of lightweight design, and improve the durability and reliability of the product, has become an urgent problem to be solved. Utility Model Content

[0004] The present invention aims to at least solve the problems of low durability and reliability of photovoltaic modules caused by the huge interlaminar shear stress generated between the polymer front sheet and the metal back sheet.

[0005] Therefore, the first aspect of this utility model provides a photovoltaic module.

[0006] In view of this, the first aspect of the present invention provides a photovoltaic module, comprising: a front panel; a power generation layer located on one side of the front panel; and a metal back panel located on the side of the power generation layer away from the front panel, wherein the metal back panel is connected to the front panel, and a groove is provided on the side of the metal back panel near the power generation layer.

[0007] The photovoltaic module provided by this utility model includes a front panel, a power generation layer, and a metal backsheet. The power generation layer is disposed on one side of the front panel, and the metal backsheet is disposed on the side of the power generation layer away from the front panel and connected to the front panel. A groove is provided on the side of the metal backsheet near the power generation layer; that is, a groove is provided on the side of the metal backsheet connected to the front panel. The groove forms a local deformation area that can alleviate interlayer shear stress. It is understood that due to the significant difference in the linear thermal expansion coefficients between the front panel and the metal backsheet, under the periodic changes in outdoor ambient temperature, this difference will cause inconsistent thermal expansion and contraction between the two layers, thereby generating huge interlayer shear stress inside the module. Therefore, this application provides a groove on the side of the metal backsheet near the power generation layer, utilizing the groove to form a preset stress guiding area and a flexible hinge on the surface of the rigid metal backsheet. When internal stress is generated between the front panel and the metal backsheet due to thermal expansion and contraction, the groove can precisely guide and release the stress, causing it to concentrate at the groove and transform into controllable micro-deformation. This avoids the disorderly accumulation of stress in key parts such as cells, solder ribbons, and bonding interfaces, reducing the risk of interlayer separation. It also ensures that the bonding interface between the encapsulation material and the front panel and metal backsheet remains stable, reducing the generation of bubbles and the possibility of complete interface detachment. This also reduces the risk of moisture and air intrusion, thereby significantly improving the long-term reliability of the photovoltaic module structure, effectively delaying module aging, and preventing permanent damage to power generation performance.

[0008] Meanwhile, the groove design simplifies the manufacturing process, eliminating the need for complex processing steps, reducing production costs, and facilitating large-scale industrial production. Therefore, the photovoltaic modules provided in this application, while adapting to various environmental conditions, possess higher energy conversion efficiency, longer service life, and lower maintenance costs.

[0009] In some embodiments, the groove extends along the surface of the plate parallel to the connection between the metal back plate and the front plate.

[0010] In these embodiments, the grooves extend parallel to the surface where the metal backplate connects to the front plate, thus mitigating interlaminar shear stress across the entire connection surface. Since temperature changes cause expansion and contraction differences between the front plate and the metal backplate across the entire connection surface, the parallel-extending grooves can absorb stress over a larger area through their localized deformation. Compared to irregular or non-parallel-extending grooves, this provides a more comprehensive and uniform stress relief effect, further reducing the risk of material interface delamination and electrical connection failure.

[0011] In some embodiments, the depth of the groove is optionally less than the thickness of the metal backing plate along its thickness direction.

[0012] In these embodiments, the groove depth is less than the thickness of the metal backsheet, allowing the metal backsheet to maintain sufficient structural strength while alleviating interlayer shear stress through the grooves. As a crucial component of photovoltaic modules, the metal backsheet needs to withstand certain external forces, such as wind and snow pressure. A suitable groove depth design avoids weakening the strength of the metal backsheet due to excessive groove depth, ensuring that it will not deform or crack due to insufficient structural strength in complex outdoor environments. This guarantees the overall structural stability of the photovoltaic module and extends its service life.

[0013] In some embodiments, the number of grooves may be multiple, and the multiple grooves are evenly distributed on the side where the metal back plate connects to the front plate.

[0014] In these embodiments, multiple grooves are evenly distributed on the side where the metal backsheet connects to the front sheet, allowing the interlaminar shear stress caused by the difference in thermal expansion coefficients to be more evenly distributed across the entire connection surface. Compared to cases with fewer or unevenly distributed grooves, the evenly distributed grooves can alleviate stress in every area where stress concentration may occur, effectively preventing material interface delamination and electrical connection failure caused by excessive local stress, and further improving the structural stability and reliability of the photovoltaic module.

[0015] In some embodiments, the number of grooves may be multiple, and the multiple grooves may be distributed in an array.

[0016] In these embodiments, multiple grooves are arranged in an array, enabling more precise stress relief. Each groove can specifically disperse and alleviate interlaminar shear stress at its location. Due to the regularity of the array, stress can be uniformly and effectively managed in both the central and edge regions of the metal backsheet. This precise stress control can prevent localized material interface delamination caused by stress concentration. For example, at the intersection of the array, stress is effectively dispersed through the combined action of grooves in multiple directions, greatly reducing the risk of interface problems at this location, thereby comprehensively improving the reliability of the photovoltaic module structure.

[0017] In some embodiments, optionally, the minimum distance between the outer contour line of the groove projected in the thickness direction of the metal backing plate and the outer edge of the metal backing plate is greater than 0.

[0018] In these embodiments, the groove maintains a certain distance from the outer edge of the metal backsheet, which enhances the structural stability of the metal backsheet edge. During the installation and use of photovoltaic modules, the edge of the metal backsheet may be subjected to additional external forces, such as the fixing forces during installation and natural forces like wind and rain. If the groove is too close to the edge, it will weaken the edge strength, easily leading to edge deformation and cracking. Maintaining a certain distance ensures that the edge area has sufficient material to withstand these external forces, maintaining the overall structural stability of the metal backsheet, thereby improving the durability of the photovoltaic module in complex environments.

[0019] In some embodiments, the projection shape of the groove in the thickness direction of the metal backing plate may be strip-shaped, wavy, or grid-shaped.

[0020] In these embodiments, different projection shapes provide diverse ways to alleviate interlayer shear stress. Strip-shaped projection grooves exhibit significant stress dispersion along their extension direction, effectively addressing stresses primarily generated in a single direction. Wavy projection grooves, due to their unique shape, possess excellent stress absorption capabilities in multiple directions, better adapting to complex stress variations. Mesh-shaped projection grooves can disperse stress omnidirectionally across the entire metal backsheet plane, comprehensively ensuring the stability of material interfaces and electrical connections. This diverse range of stress relief methods enables photovoltaic modules to adapt to different outdoor environments and operating conditions, improving their reliability and durability.

[0021] In some embodiments, the cross-sectional shape of the groove may optionally be at least one of V-shape, U-shape, rectangle or arc.

[0022] In these embodiments, different groove cross-sectional shapes provide targeted mitigation methods for the characteristics of interlaminar shear stress. V-shaped cross-sections effectively disperse stress using a wedge-shaped structure. U-shaped cross-sections protect the connection interface through a larger accommodating space and vertical walls. Rectangular cross-sections enhance backsheet strength and disperse stress with a simple, regular structure. Arc-shaped cross-sections guide stress distribution evenly with a smooth curve. These grooves of different shapes can more effectively address interlaminar shear stress according to the specific stress conditions in actual application scenarios, reducing the possibility of material interface delamination and electrical connection failure, and improving the structural stability and reliability of photovoltaic modules.

[0023] In some embodiments, the front panel may optionally include: a first protective layer disposed on the side of the power generation layer away from the metal backplate; and a first adhesive film layer disposed on the side of the first protective layer close to the power generation layer.

[0024] In these embodiments, the multi-layered structure design tightly bonds each adhesive film layer to adjacent functional layers, forming a stable integrated structure between the front panel, the metal back panel, and the internal layers. In outdoor environments, this multi-layered composite structure maintains excellent stability even under drastic temperature changes, strong winds, sandstorms, and other harsh weather conditions, reducing the risk of module damage due to relative displacement or separation between materials and extending the lifespan of the photovoltaic modules.

[0025] Meanwhile, the first protective layer protects the power generation layer and other internal structures, ensuring that the power generation layer can operate in a stable environment. The excellent adhesion of the first encapsulant layer also helps improve the electrical insulation performance inside the module, reducing performance degradation caused by leakage and other problems, thus comprehensively improving the overall performance and reliability of the photovoltaic module and enabling it to better meet the needs of different application scenarios.

[0026] In some embodiments, the power generation layer may optionally include a plurality of solar cells, which are spaced apart along a first direction; the number of grooves may be a plurality, which are spaced apart along the first direction or spaced apart along a second direction; wherein the first direction is perpendicular to the second direction.

[0027] In these embodiments, the solar cells in the power generation layer are spaced apart along a first direction, while the grooves are spaced apart along the first direction or a second direction perpendicular to it. This design effectively matches the thermal stress distribution of the solar cells in different directions. Since the solar cells expand and contract differently in different directions, when the grooves are arranged along the first direction, they directly alleviate the stress caused by thermal expansion and contraction in the arrangement direction. When the grooves are arranged along the second direction, they can cope with stress changes in the solar cells perpendicular to the arrangement direction. Through this targeted stress relief, problems such as microcracks in the solar cells and solder joint detachment caused by stress are reduced, ensuring the stability of the electrical connection of the power generation layer and improving the power generation performance and reliability of the photovoltaic module.

[0028] In some embodiments, the metal backplate may optionally include at least one or a combination of the following: aluminum plate, aluminized zinc steel plate, and aluminum-magnesium-manganese plate.

[0029] These embodiments offer a variety of metal backsheet material options, allowing photovoltaic modules to be optimized for different application scenarios and performance requirements. For applications prioritizing lightweight design, aluminum sheets are ideal. For environments requiring high strength and good corrosion resistance, aluminized zinc steel sheets are more suitable. And for projects balancing aesthetics and performance, aluminum-magnesium-manganese sheets offer significant advantages. This diverse range of choices enhances the applicability of photovoltaic modules in various fields, expanding their market application scope.

[0030] In some embodiments, the thickness of the metal backing plate is optionally greater than or equal to 0.4 mm and less than or equal to 2.5 mm, and the depth of the groove is less than or equal to half the thickness of the metal backing plate.

[0031] In these embodiments, a clever balance is struck between the weight and strength of the metal backsheet by limiting its thickness range. A thinner thickness achieves lightweighting, meeting the requirements of load-sensitive scenarios and enabling the photovoltaic modules to be widely used in various types of buildings, including existing buildings and light steel structure buildings. Conversely, appropriately increasing the thickness provides sufficient strength when needed, ensuring the reliability of the photovoltaic modules in harsh environments, guaranteeing their normal power generation function, and extending their service life. This balance helps expand the application range of photovoltaic modules and improve their applicability in different scenarios. The depth of the groove is less than or equal to half the thickness of the metal backsheet, allowing the metal backsheet to alleviate interlaminar shear stress through the groove while still maintaining sufficient structural strength.

[0032] Additional aspects and advantages of this invention will become apparent in the following description or may be learned by practice of this invention. Attached Figure Description

[0033] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0034] Figure 1 A cross-sectional view of the metal backplate of a photovoltaic module according to an embodiment of the present invention is shown.

[0035] Figure 2 One of the structural schematic diagrams of the metal backplate of a photovoltaic module according to an embodiment of the present invention is shown;

[0036] Figure 3 This is a second schematic diagram showing the structure of the metal backplate of a photovoltaic module according to an embodiment of the present invention;

[0037] Figure 4 The third schematic diagram shows the structure of the metal backplate of a photovoltaic module according to an embodiment of the present invention;

[0038] Figure 5 The fourth schematic diagram shows the structure of the metal backplate of a photovoltaic module according to an embodiment of the present invention;

[0039] Figure 6 A schematic diagram of the structure of a photovoltaic module according to an embodiment of the present invention is shown.

[0040] Among them, 1 is a photovoltaic module; 11 is a front panel; 111 is a first protective layer; 112 is a first encapsulant layer; 12 is a power generation layer; 121 is a solar cell; 13 is a metal backplate; 14 is a groove; 15 is a second encapsulant layer; 16 is a second protective layer; and 17 is a third encapsulant layer. Detailed Implementation

[0041] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0042] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0043] The following reference Figures 1 to 6 This invention describes a photovoltaic module proposed according to some embodiments of the present invention.

[0044] According to an embodiment of the first aspect of the present invention, such as Figure 1 , Figure 2 , Figure 3 , Figure 4, Figure 5 and Figure 6 As shown, the first aspect of this utility model provides a photovoltaic module 1, including a front panel 11, a power generation layer 12, and a metal back panel 13. The power generation layer 12 is located on one side of the front panel 11. The metal back panel 13 is located on the side of the power generation layer 12 away from the front panel 11, and the metal back panel 13 is connected to the front panel 11. A groove 14 is provided on the side of the metal back panel 13 near the power generation layer 12.

[0045] The photovoltaic module 1 provided by this utility model includes a front panel 11, a power generation layer 12, and a metal backsheet 13. The power generation layer 12 is disposed on one side of the front panel, and the metal backsheet 13 is disposed on the side of the power generation layer 12 away from the front panel 11 and connected to the front panel 11. A groove 14 is provided on the side of the metal backsheet 13 near the power generation layer 12, that is, a groove 14 is provided on the side of the metal backsheet 13 connected to the front panel 11. The groove 14 forms a local deformation area that can alleviate interlayer shear stress. It is understood that due to the significant difference in the linear thermal expansion coefficient between the front panel 11 and the metal backsheet 13, under the periodic changes in outdoor ambient temperature, this difference will cause inconsistent thermal expansion and contraction of the two layers of materials, thereby generating huge interlayer shear stress inside the module. Therefore, this application provides a groove 14 on the side of the metal backsheet 13 near the power generation layer 12, and uses the groove 14 to form a preset stress guiding area and flexible hinge on the surface of the rigid metal backsheet 13. When internal stress is generated between the front panel 11 and the metal backplate 13 due to thermal expansion and contraction, the groove 14 can accurately guide and release the stress, causing it to concentrate at the groove 14 and be transformed into a controllable micro-deformation. This avoids the disorderly accumulation of stress in key parts such as the cell 121, solder ribbon, and bonding interface, reducing the risk of interlayer separation. It also ensures that the bonding interface between the encapsulation material and the front panel 11 and the metal backplate 13 remains stable, reducing the generation of bubbles and the complete detachment of the interface. This reduces the risk of moisture and air intrusion, thereby significantly improving the long-term reliability of the photovoltaic module 1 structure, effectively delaying module aging, and avoiding permanent damage to power generation performance.

[0046] Meanwhile, the design of the groove 14 simplifies the manufacturing process, eliminating the need for complex processing steps, reducing production costs, and facilitating large-scale industrial production. Therefore, the photovoltaic module 1 provided in this application, while adapting to various environmental conditions, possesses higher energy conversion efficiency, longer service life, and lower maintenance costs.

[0047] The groove 14 can be a regularly arranged square groove 14, a continuous wavy groove 14, or other types of groove 14. Taking the wavy groove 14 as an example, when the temperature changes, the front plate 11 and the metal back plate 13 expand and contract to different degrees due to their different coefficients of thermal expansion. The wavy groove 14 on the metal back plate 13 can absorb and disperse the stress caused by this difference in expansion and contraction to a certain extent. The metal back plate 13 material at the groove 14 can undergo local deformation relatively more easily, thereby alleviating the overall interlaminar shear stress.

[0048] In some embodiments, the groove 14 may extend along a plate surface parallel to the connection between the metal back plate 13 and the front plate 11.

[0049] In these embodiments, the groove 14 extends parallel to the plane where the metal backplate 13 connects to the front plate 11. This means that the groove 14 extends on the plane where the metal backplate 13 and the front plate 11 are attached. For example, when the metal backplate 13 is rectangular, the groove 14 may extend along the long or short side of the rectangle, or it may be distributed in a grid pattern across the entire connecting surface. The groove 14 extends parallel to the plane where the metal backplate 13 connects to the front plate 11, thus alleviating interlaminar shear stress across the entire connecting surface. Since temperature changes cause expansion and contraction differences between the front plate 11 and the metal backplate 13 across the entire connecting surface, the parallel-extending groove 14 can absorb stress over a larger area through its own local deformation. Compared to irregular or non-parallel-extending grooves 14, the stress relief effect is more comprehensive and uniform, further reducing the risk of material interface delamination and electrical connection failure.

[0050] In some embodiments, optionally, along the thickness direction of the metal backing plate 13 (e.g. Figure 1 (in the direction indicated by T), the depth of the groove 14 is less than the thickness of the metal back plate 13.

[0051] In these embodiments, the depth of the groove 14 along the thickness direction of the metal backsheet 13 is less than the thickness of the metal backsheet 13 itself. This indicates that the groove 14 will not penetrate the metal backsheet 13. For example, if the thickness of the metal backsheet 13 is 5 mm, the depth of the groove 14 may be designed to be 2 mm. The groove 14 depth being less than the thickness of the metal backsheet 13 allows the metal backsheet 13 to maintain sufficient structural strength while relieving interlayer shear stress through the groove 14. As an important component of the photovoltaic module 1, the metal backsheet 13 needs to withstand certain external forces, such as wind force and snow pressure. The appropriate groove 14 depth design avoids weakening the strength of the metal backsheet 13 due to excessive groove 14, ensuring that it will not deform or crack due to insufficient structural strength in complex outdoor environments, thus ensuring the overall structural stability of the photovoltaic module 1 and extending its service life.

[0052] In some embodiments, the number of grooves 14 may be multiple, and the multiple grooves 14 are evenly distributed on the side where the metal back plate 13 is connected to the front plate 11.

[0053] In these embodiments, a plurality of grooves 14 are provided on the side where the metal backplate 13 connects to the front plate 11, and these grooves 14 are evenly distributed. This means that the grooves 14 are arranged in a certain pattern on the side where the metal backplate 13 connects to the front plate 11 to achieve a uniform effect. For example, assuming the metal backplate 13 is rectangular, the plurality of grooves 14 can be arranged at equal intervals along the long and short sides, forming a grid-like distribution. The plurality of grooves 14 are evenly distributed on the side where the metal backplate 13 connects to the front plate 11, so that the interlaminar shear stress caused by the difference in the coefficient of thermal expansion can be more evenly distributed across the entire connection surface. Compared with the case where the number of grooves 14 is small or the distribution is uneven, the evenly distributed plurality of grooves 14 can play a mitigating role in every area where stress concentration may occur, effectively avoiding material interface delamination and electrical connection failure caused by excessive local stress, and further improving the structural stability and reliability of the photovoltaic module 1.

[0054] In some embodiments, the number of grooves 14 may be multiple, and the multiple grooves 14 may be distributed in an array.

[0055] In these embodiments, the grooves 14 on the side connecting the metal backplate 13 and the front plate 11 are arranged in an array. An array arrangement means that the grooves 14 are arranged in rows and columns in an orderly manner, similar to a matrix. For example, when the metal backplate 13 is rectangular, the grooves 14 are arranged neatly like squares on a chessboard on the plane connecting it to the front plate 11. This arrangement ensures that stress is effectively managed across the entire connection surface of the metal backplate 13. Compared to irregular distributions, this array arrangement can more accurately and systematically address the interlaminar shear stress caused by the difference in the linear thermal expansion coefficients between the front plate 11 and the metal backplate 13. The array arrangement of multiple grooves 14 makes stress relief more precise. Each groove 14 can specifically disperse and alleviate interlaminar shear stress at its location. Due to the regularity of the array, stress can be uniformly and effectively managed in both the central and edge areas of the metal backplate 13. This precise stress control can avoid local material interface delamination caused by stress concentration. For example, at the intersection of the array, the stress is effectively dispersed by the combined action of grooves 14 in multiple directions, which greatly reduces the risk of interface problems at this location, thereby comprehensively improving the reliability of the photovoltaic module 1 structure.

[0056] In some embodiments, optionally, the minimum distance between the outer contour line of the groove 14 projected in the thickness direction of the metal backing plate 13 and the outer edge of the metal backing plate 13 is greater than 0.

[0057] In these embodiments, the outer contour line projected by the groove 14 in the thickness direction of the metal backsheet 13 refers to the shape boundary of the groove 14 as viewed from a direction perpendicular to the metal backsheet 13. The minimum distance between this projected outer contour line and the outer edge of the metal backsheet 13 is greater than 0, meaning that the groove 14 is not set tightly against the edge of the metal backsheet 13. For example, if the metal backsheet 13 is rectangular, the projected outer contour line of the groove 14 is a certain distance from all four sides of the metal backsheet 13. This design avoids excessive weakening of the structural integrity of the edge of the metal backsheet 13 by the groove 14, while also ensuring that the groove 14 plays an effective role in alleviating interlayer shear stress. Maintaining a certain distance between the groove 14 and the outer edge of the metal backsheet 13 enhances the structural stability of the edge of the metal backsheet 13. During the installation and use of the photovoltaic module 1, the edge of the metal backsheet 13 may be subjected to additional external forces, such as the fixing force during installation, and natural forces such as wind and rain. If the groove 14 is too close to the edge, it will weaken the strength at the edge, easily leading to edge deformation and cracking. Maintaining a certain distance ensures that there is enough material in the edge area to withstand these external forces, maintain the stability of the overall structure of the metal backsheet 13, and thus improve the durability of the photovoltaic module 1 in complex environments.

[0058] In some embodiments, the projection shape of the groove 14 in the thickness direction of the metal backing plate 13 may be strip-shaped, wavy, or grid-shaped.

[0059] In these embodiments, when the projection of the groove 14 onto the thickness direction of the metal backplate 13 is strip-shaped, it is as if there is a long, thin line-shaped groove 14 projected onto the metal backplate 13. For example, the strip-shaped projection can be distributed along the length direction of the metal backplate 13, and the length of the strip-shaped projection can be determined according to the size of the metal backplate 13. For example, if the metal backplate 13 is 2 meters long, the length of the strip-shaped projection can be set to 1.8 meters. This strip-shaped groove 14 can effectively disperse the stress caused by the difference in thermal expansion between the front plate 11 and the metal backplate 13 in its extending direction.

[0060] When the projected shape is wavy, the groove 14 appears to have a wave-like undulating shape when viewed from a direction perpendicular to the metal backing plate 13. Compared to the strip-shaped groove 14, the unique undulating shape of the wavy groove 14 can absorb and disperse interlaminar shear stress in multiple directions, because the thermal expansion and contraction of different parts can be better coordinated under the wavy contour, reducing stress concentration.

[0061] The grid-shaped projection is formed by the projection of the horizontal and vertical grooves 14 to form a grid-like pattern. This grid-shaped groove 14 design can disperse stress in all directions on the entire plane of the metal back plate 13. No matter in which direction the stress is generated, it can be effectively relieved through the grid structure.

[0062] Different projection shapes offer diverse ways to alleviate interlayer shear stress. The strip-shaped projection groove 14 exhibits significant stress dispersion along its extension direction, effectively addressing stresses primarily generated in a single direction. The wavy projection groove 14, due to its unique shape, possesses excellent stress absorption capabilities in multiple directions, better adapting to complex stress variations. The grid-shaped projection groove 14 can disperse stress omnidirectionally across the entire plane of the metal backsheet 13, comprehensively ensuring the stability of material interfaces and electrical connections. This diverse range of stress relief methods enables the photovoltaic module 1 to adapt to different outdoor environments and operating conditions, enhancing its reliability and durability.

[0063] In some embodiments, the cross-sectional shape of the groove 14 may optionally be at least one of V-shape, U-shape, rectangle or arc.

[0064] In these embodiments, different groove 14 cross-sectional shapes provide targeted mitigation methods for the characteristics of interlaminar shear stress. V-shaped cross-sections effectively disperse stress using a wedge-shaped structure. U-shaped cross-sections protect the connection interface through a larger accommodating space and vertical walls. Rectangular cross-sections enhance the backsheet strength and disperse stress with a simple, regular structure. Arc-shaped cross-sections guide stress distribution evenly with a smooth curve. These grooves 14 of different shapes can more effectively cope with interlaminar shear stress according to the specific stress conditions in actual application scenarios, reducing the possibility of material interface delamination and electrical connection failure, and improving the structural stability and reliability of the photovoltaic module 1.

[0065] In some embodiments, the front panel 11 may optionally include: a first protective layer 111 disposed on the side of the power generation layer 12 away from the metal back panel 13; and a first adhesive film layer 112 disposed on the side of the first protective layer 111 close to the power generation layer 12.

[0066] In these embodiments, a first protective layer 111 is disposed on the side of the power generation layer 12 facing away from the metal backsheet 13. A first adhesive film layer 112 is disposed on the side of the first protective layer 111 close to the power generation layer 12, thereby enabling connection. Through the multi-layer structure design, each adhesive film layer tightly bonds adjacent functional layers, forming a stable integral structure between the front panel 11, the metal backsheet 13, and the internal layers. In outdoor environments, regardless of drastic temperature changes or harsh weather conditions such as strong winds and sandstorms, this multi-layer composite structure maintains good stability, reducing the risk of module damage caused by relative displacement or separation between materials, and extending the service life of the photovoltaic module.

[0067] In some embodiments, the photovoltaic module may optionally include: a second encapsulant layer 15 disposed on the side of the power generation layer 12 away from the first protective layer 111; a second protective layer 16 disposed on the side of the second encapsulant layer 15 away from the power generation layer 12; and a third encapsulant layer 17 disposed on the side of the second protective layer 16 away from the second encapsulant layer 15.

[0068] In these embodiments, the third encapsulant layer 17 is disposed on the side of the second protective layer 16 away from the second encapsulant layer 15, that is, the third encapsulant layer 17 is disposed on the side of the metal backsheet 13, serving to bond the metal backsheet 13 to the second protective layer 16. For example, the third encapsulant layer 17 can be made of ethylene-vinyl acetate (EVA) film, which has good adhesive properties and can firmly bond the metal backsheet 13 to the second protective layer 16, ensuring that the connection between the metal backsheet 13 and the second protective layer 16 remains stable in outdoor environments when facing temperature changes, humidity fluctuations, etc., preventing external factors such as moisture from penetrating the module. The second protective layer 16 is located on the side of the third encapsulant layer 17 away from the metal backsheet 13, providing initial protection for the photovoltaic module 1. It can have a certain degree of wear resistance and weather resistance, protecting the internal structure from external physical damage and environmental erosion. The second encapsulant layer 15 is disposed on the side of the second protective layer 16 opposite to the third encapsulant layer 17. Its function is similar to that of the third encapsulant layer 17, serving to bond the second protective layer 16 to the power generation layer 12. EVA encapsulant can also be used to ensure a tight bond between the power generation layer 12 and the second protective layer 16, guaranteeing the stability of the entire module structure. The power generation layer 12 is the core component of the photovoltaic module 1, typically composed of multiple solar cells 121, thereby achieving photoelectric conversion and providing power to external devices. The performance of the power generation layer 12 directly determines the power generation efficiency of the photovoltaic module 1. The first encapsulant layer 112 is located on the side of the power generation layer 12 opposite to the second encapsulant layer 15, serving to bond the power generation layer 12 to the first protective layer 111, maintaining the integrity of the module structure. EVA encapsulant can also be used to ensure a strong and reliable connection between the power generation layer 12 and the first protective layer 111. The first protective layer 111 is disposed on the side of the first encapsulant layer 112 opposite to the power generation layer 12, further enhancing the protection of the internal structure. It can be a PET (Polyethylene Terephthalate Film) film with high light transmittance and high weather resistance.

[0069] Meanwhile, the first protective layer 111 and the second protective layer 16 protect the power generation layer 12 and other internal structures from both sides, ensuring that the power generation layer 12 can operate in a stable environment. The good adhesion of each film layer also helps to improve the electrical insulation performance inside the module, reduce performance degradation caused by leakage and other problems, and comprehensively improve the overall performance and reliability of the photovoltaic module 1, enabling it to better meet the needs of different application scenarios.

[0070] In some embodiments, the power generation layer 12 may optionally include a plurality of battery cells 121, which are spaced apart along a first direction; the number of grooves 14 may be a plurality, which are spaced apart along the first direction or spaced apart along a second direction; wherein the first direction is perpendicular to the second direction.

[0071] In these embodiments, the power generation layer 12 is composed of multiple solar cells 121, which are spaced apart along a specific direction (defined as the first direction). For example, assuming the photovoltaic module 1 is rectangular, the first direction can be its long side direction. The solar cells 121 are arranged sequentially along the long side direction, and there is a preset interval between adjacent solar cells 121. This spacing arrangement ensures that each solar cell 121 can fully receive sunlight, avoids mutual shading, and improves power generation efficiency. The grooves 14 on the metal backplate 13 also have a specific arrangement. There are multiple grooves 14, which can be spaced apart along the same first direction as the arrangement of the solar cells 121, or spaced apart along a second direction perpendicular to the first direction. If the first direction is the long side direction of the photovoltaic module 1, then the second direction is the short side direction. Conversely, if the second direction is the long side direction of the photovoltaic module 1, then the first direction is the short side direction.

[0072] In the power generation layer 12, the solar cells 121 are arranged at intervals along a first direction, while the grooves 14 are arranged at intervals along the first direction or a second direction perpendicular to it. This design effectively matches the thermal stress distribution of the solar cells 121 in different directions. Since the thermal expansion and contraction of the solar cells 121 differ in different directions, when the grooves 14 are arranged along the first direction, they directly alleviate the stress generated by thermal expansion and contraction in the solar cells 121 along the arrangement direction. When the grooves 14 are arranged along the second direction, they can cope with stress changes in the solar cells 121 perpendicular to the arrangement direction. Through this targeted stress relief, problems such as microcracks in the solar cells 121 and solder joint detachment caused by stress are reduced, ensuring the stability of the electrical connections of the power generation layer 12 and improving the power generation performance and reliability of the photovoltaic module 1.

[0073] The first direction can be Figure 4 The direction indicated by A in the diagram, the second direction could be... Figure 4 The direction indicated by B in the middle. Figure 4 The middle battery cell 121 is not shown.

[0074] In some embodiments, the metal backplate 13 may optionally include at least one or a combination of the following: an aluminum plate, an aluminized zinc steel plate, and an aluminum-magnesium-manganese plate.

[0075] In these embodiments, aluminum plates, used as the metal backsheet material 13, are characterized by low density and light weight, effectively reducing the overall weight of the photovoltaic module 1 and making it more suitable for use in weight-sensitive building scenarios, such as light steel structure buildings or existing buildings with strict load-bearing limitations. Aluminum-zinc coated steel plates are steel plates coated with an aluminum-zinc alloy layer, combining the corrosion resistance of aluminum with the cathodic protection properties of zinc. This material has high strength and can provide reliable structural support for the photovoltaic module 1. Aluminum-magnesium-manganese plates are widely used due to their good flexibility, corrosion resistance, and aesthetics. They contain alloying elements such as magnesium and manganese, giving the material high strength and weather resistance. Providing a variety of metal backsheet material options 13 allows the photovoltaic module 1 to be optimized according to different application scenarios and performance requirements. For scenarios requiring lightweighting, aluminum plates are an ideal choice. For environments requiring high strength and good corrosion resistance, aluminum-zinc coated steel plates are more suitable. For projects that balance aesthetics and performance, aluminum-magnesium-manganese plates offer advantages. This diverse selection improves the applicability of the photovoltaic module 1 in different fields and expands its market application scope.

[0076] In some embodiments, the thickness of the metal backing plate 13 is optionally greater than or equal to 0.4 mm and less than or equal to 2.5 mm, and the depth of the groove 14 is less than or equal to half the thickness of the metal backing plate 13.

[0077] In these embodiments, by limiting the thickness range of the metal backsheet 13, the weight and strength of the metal backsheet 13 are cleverly balanced. A thinner thickness achieves lightweighting, meeting the needs of load-sensitive scenarios and enabling the photovoltaic module 1 to be widely used in various types of buildings, including existing buildings and light steel structure buildings. On the other hand, appropriately increasing the thickness provides sufficient strength when needed, ensuring the reliability of the photovoltaic module 1 in harsh environments, guaranteeing its normal power generation function, and extending its service life. This balance helps to expand the application range of the photovoltaic module 1 and improve its applicability in different scenarios. The depth of the groove 14 is less than or equal to half the thickness of the metal backsheet 13, allowing the metal backsheet 13 to alleviate interlaminar shear stress through the groove 14 while still maintaining sufficient structural strength.

[0078] In some embodiments, the thickness of the metal backplate 13 may be greater than or equal to 0.5 mm and less than or equal to 2 mm.

[0079] In some embodiments, the thickness of the metal backplate 13 is optionally 0.7 mm.

[0080] In some embodiments, the thickness of the metal backplate 13 is optionally 0.9 mm.

[0081] In some embodiments, the thickness of the metal backplate 13 is optionally 1 mm.

[0082] In some embodiments, the thickness of the metal backplate 13 is optionally 1.2 mm.

[0083] In some embodiments, the thickness of the metal backplate 13 is optionally 1.5 mm.

[0084] In some embodiments, the thickness of the metal backplate 13 is optionally 1.8 mm.

[0085] In some embodiments, the photovoltaic module 1 may optionally include photovoltaic tiles, photovoltaic panels, etc.

[0086] The first aspect of this utility model discloses a photovoltaic module, comprising an upper protective layer (first protective layer), a power generation core layer (power generation layer), a lower protective layer (second protective layer), and an integral rigid metal support plate (metal backsheet). The upper protective layer is composed of a high-transmittance, weather-resistant PET film. The power generation core layer includes solar cells and encapsulation materials covering them; preferably, the solar cells are small and arranged with certain gaps. The lower protective layer is composed of PET film. The integral rigid metal support plate serves as the main body for structural load-bearing, installation, and waterproofing; the integral rigid metal support plate is a complete, uncut, continuous planar plate, that is, the integral rigid metal support plate has grooves.

[0087] In some embodiments, the upper protective layer, the power generation core layer, the lower protective layer, and the metal support plate are optionally bonded together by a lamination process to form a power generation module.

[0088] In some embodiments, the extension direction of the groove may optionally be configured to be parallel to the arrangement direction of the battery cells or perpendicular to the arrangement direction of the battery cells.

[0089] In some embodiments, the grooves may be continuously extending strips or discontinuously distributed arrays (such as a collection of dots or short line segments).

[0090] In some embodiments, the metal backing plate is preferably made of aluminum plate, aluminized zinc steel plate, or aluminum-magnesium-manganese plate with a thickness of 0.5mm-2mm.

[0091] In some embodiments, the grooves may be processed by chemical etching or laser cutting.

[0092] These uncut grooves form pre-defined stress-guiding zones and flexible hinges on the surface of the rigid metal backsheet. When the PET composite layer and the metal backsheet generate internal stress due to thermal expansion and contraction, these grooves can precisely guide and release the stress, causing it to concentrate at the grooves and transform into controllable micro-deformation, thereby preventing the disorderly accumulation of stress in critical areas such as the battery cells, solder strips, and bonding interfaces.

[0093] The beneficial effects of this application are as follows:

[0094] Precise stress management: By designing the direction, spacing and depth of the grooves, thermal stress can be actively guided and consumed, transforming destructive interlaminar shear stress into localized flexible deformation that is harmless to the power generation module, thus systematically improving the product's thermal fatigue life.

[0095] Maintaining overall rigidity: Because the groove is "not cut through", the metal backing plate maintains its integrity and high strength as the main body for installation and load-bearing on a macroscopic level, without affecting its overall rigidity and mechanical performance on the roof.

[0096] High design flexibility: The choice of parallel or vertical direction and the combination of continuous or discontinuous forms enable the design to be customized for stress optimization for photovoltaic tiles of different sizes and cell arrangements, making it widely applicable.

[0097] In one specific embodiment, a 1.2mm thick aluminum-magnesium-manganese plate has parallel grooves, 0.3mm wide and 0.6mm deep, laser-cut on its surface with a groove spacing of 100mm, aligned with the principal stress direction of the photovoltaic tile. Actual measurements show that after undergoing 1000 cycles of thermal cycling from -40℃ to 85℃, this structure showed no cracks or deformation, demonstrating significant thermal stress release while maintaining the overall rigidity and installation stability of the metal backing plate, making it suitable for long-term operation in various roofing environments.

[0098] In this utility model, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0099] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. 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.

[0100] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A photovoltaic module, characterized in that, include: front panel; A power generation layer is located on one side of the front panel; A metal backplate is located on the side of the power generation layer away from the front plate. The metal backplate is connected to the front plate, and a groove is provided on the side of the metal backplate near the power generation layer.

2. The photovoltaic module according to claim 1, characterized in that, The groove extends along the surface of the plate parallel to the connection between the metal back plate and the front plate.

3. The photovoltaic module according to claim 1, characterized in that, Along the thickness direction of the metal backing plate, the depth of the groove is less than the thickness of the metal backing plate.

4. The photovoltaic module according to claim 1, characterized in that, The number of grooves is multiple, and the multiple grooves are evenly distributed on the side where the metal back plate connects to the front plate; and / or The number of grooves is multiple, and the multiple grooves are distributed in an array.

5. The photovoltaic module according to claim 1, characterized in that, The minimum distance between the outer contour line of the groove projected in the thickness direction of the metal back plate and the outer edge of the metal back plate is greater than 0.

6. The photovoltaic module according to claim 1, characterized in that, The projection shape of the groove in the thickness direction of the metal back plate is strip-shaped, wavy, or grid-shaped; or The cross-sectional shape of the groove is at least one of V-shape, U-shape, rectangle or arc.

7. The photovoltaic module according to any one of claims 1 to 6, characterized in that, The front panel includes: A first protective layer is disposed on the side of the power generation layer opposite to the metal backplate; The first adhesive film layer is disposed on the side of the first protective layer near the power generation layer.

8. The photovoltaic module according to any one of claims 1 to 6, characterized in that, The power generation layer includes multiple solar cells, which are arranged at intervals along a first direction. The number of grooves is multiple, and the multiple grooves are arranged at intervals along the first direction, or the multiple grooves are arranged at intervals along the second direction; Wherein, the first direction is perpendicular to the second direction.

9. The photovoltaic module according to any one of claims 1 to 6, characterized in that, The metal backplate includes at least one or a combination of the following: aluminum plate, aluminized zinc steel plate, and aluminum-magnesium-manganese plate.

10. The photovoltaic module according to any one of claims 1 to 6, characterized in that, The thickness of the metal back plate is greater than or equal to 0.4 mm and less than or equal to 2.5 mm, and the depth of the groove is less than or equal to half the thickness of the metal back plate.

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