Panel for photovoltaic module and photovoltaic module

Abstract

The utility model provides a photovoltaic assembly panel and a photovoltaic assembly, and belongs to the technical field of photovoltaic assemblies, a weight reduction cavity is arranged in the panel, and the weight reduction cavity penetrates through two opposite side surfaces of the panel. According to the utility model, the weight reduction cavity is arranged in the panel to reduce the weight of the panel, so that the self weight of the photovoltaic module can be reduced, the problem that the photovoltaic module is bent downwards due to the heavy weight of the panel is avoided, and the power reduction of the module due to the bending of the photovoltaic module can be further avoided; and the problem that the service life is shortened due to hidden crack defects caused by bending is solved. The weight reduction cavity is arranged in the panel, so that the panel has bending resistance, and the bending resistance of the photovoltaic module is enhanced; the weight reduction cavity is formed in the panel, refraction can be generated when sunlight irradiates, the light absorption capacity of the assembly is improved, and therefore the power of the assembly is improved; and the weight reduction cavity is arranged in the panel, so that the transportation cost and the installation difficulty of the photovoltaic module can be reduced.

Description

Technical Field

[0001] This utility model belongs to the field of photovoltaic module technology, specifically relating to a photovoltaic module panel and a photovoltaic module. Background Technology

[0002] In photovoltaic (PV) modules, the panel glass used is typically low-iron ultra-white tempered glass with a textured or smooth finish, usually 2mm or 4mm thick. Tempered glass, a crucial component of PV modules, not only protects the cells but also provides essential light transmittance to withstand the challenges of diurnal temperature variations and harsh weather. This glass must possess high light transmittance, typically exceeding 91%, and its spectral response wavelength should cover the range of 320–1100nm, while maintaining high reflectivity for infrared light exceeding 1200nm. Furthermore, this glass undergoes an ultra-white tempering process; low-iron ultra-white means that the iron content is low, typically less than or equal to 150ppm, thus enhancing light transmittance. Viewed from the edge, this glass exhibits a flawless white appearance, contrasting sharply with ordinary greenish glass, ensuring its quality and performance. In addition, textured glass undergoes anti-reflective treatment on its surface using physical and chemical methods, creating a velvety structure that increases the amount of light incident.

[0003] Therefore, tempered glass used as photovoltaic module panels must not only have excellent light transmittance and hardness, but also be able to withstand day-night temperature differences and harsh weather conditions to protect the solar cells.

[0004] However, as the size of photovoltaic modules continues to increase, the weight and size of the glass used also continue to increase. 80% of the weight of a photovoltaic module is concentrated on the glass, which causes the photovoltaic module to bend downwards due to gravity. This has a great impact on the transportation, installation and service life of photovoltaic modules. Utility Model Content

[0005] This utility model provides a photovoltaic panel and a photovoltaic module, which aims to reduce the weight of the panel, prevent the photovoltaic module from bending downward due to gravity, reduce the impact on transportation, installation and service life, and improve the light transmittance and photoelectric conversion efficiency of the photovoltaic module.

[0006] Firstly, to achieve the above objectives, the technical solution adopted by this utility model is: to provide a panel for photovoltaic modules, wherein a weight-reducing cavity is provided inside the panel, and the weight-reducing cavity extends through the two opposite sides of the panel.

[0007] In conjunction with the first aspect, in one feasible manner, a plurality of weight-reducing cavities are provided at intervals along the length of the panel, the weight-reducing cavities being parallel to the long side of the panel and penetrating the side surfaces where the two short sides of the panel are located.

[0008] In conjunction with the first aspect, in one feasible manner, the weight reduction cavity is disposed between two adjacent battery strings inside, and the width of the weight reduction cavity is not greater than the distance between the two adjacent battery strings.

[0009] In conjunction with the first aspect, in one feasible manner, the cross-sectional profile of the weight-reducing cavity is triangular.

[0010] In conjunction with the first aspect, in one feasible manner, the triangle is an equilateral triangle.

[0011] In conjunction with the first aspect, in one feasible manner, the vertex of the triangle is close to the light-receiving surface of the panel exposed to the atmosphere, the base of the triangle is parallel to the light-receiving surface of the panel, and close to the inner side of the panel facing away from the light-receiving surface.

[0012] In conjunction with the first aspect, in one feasible manner, the distance from the vertex of the triangle to the light-receiving surface is greater than the distance from the base of the triangle to the inner surface.

[0013] In conjunction with the first aspect, in one feasible manner, the panel is tempered glass.

[0014] In conjunction with the first aspect, in one feasible manner, the side of the panel is provided with an adhesive strip to seal the weight-reduction cavity.

[0015] Secondly, this utility model embodiment also provides a photovoltaic module, including the aforementioned photovoltaic module panel.

[0016] Compared with the prior art, the photovoltaic panel and photovoltaic module provided by this utility model have the following advantages: By setting a weight-reducing cavity inside the panel, the weight of the panel is reduced, which not only reduces the weight of the photovoltaic module itself and avoids the problem of the photovoltaic module bending downward due to the heavy panel, but also avoids the problem of reduced module power caused by bending and shortened service life due to microcrack defects caused by bending; the weight-reducing cavity inside the panel makes the panel form a box beam-like structure, which has bending resistance and enhances the bending resistance of the photovoltaic module; the weight-reducing cavity inside the panel can also generate refraction when sunlight shines on it, improving the light absorption capacity of the module and thus increasing the module power; by setting a weight-reducing cavity inside the panel, the weight of the photovoltaic module is reduced, which also reduces the transportation cost and installation difficulty of the photovoltaic module. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a photovoltaic module panel provided in an embodiment of the present invention;

[0018] Figure 2A side view of the photovoltaic module panel provided in an embodiment of this utility model;

[0019] Figure 3 This is a schematic diagram of the structure of a photovoltaic module provided in an embodiment of the present utility model;

[0020] Explanation of reference numerals in the attached figures:

[0021] 1. Panel; 2. Weight reduction cavity; 3. Light-transmitting surface; 4. Battery cells; 5. Back panel. Detailed Implementation

[0022] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0023] Currently, in the face of increasingly larger photovoltaic modules, the existing method to avoid bending due to increased gravity is to add a crossbeam in the middle of the module. This method not only wastes manpower and financial resources and is too costly, but also affects the normal use of the module.

[0024] Please refer to the following: Figure 1 and Figure 2 The photovoltaic module panel provided by this utility model will now be described. The photovoltaic module panel has a weight-reducing cavity 2 provided in the panel 1, and the weight-reducing cavity 2 passes through the two opposite sides of the panel 1.

[0025] Compared with the prior art, the photovoltaic panel 1 and photovoltaic module provided by this utility model have the following advantages: By setting a weight-reducing cavity 2 inside the panel 1, the weight of the panel 1 is reduced, which not only reduces the weight of the photovoltaic module itself and avoids the problem of the photovoltaic module bending downward due to the heavy weight of the panel 1, but also avoids the reduction in module power caused by bending and the shortening of service life due to microcrack defects caused by bending; by setting a weight-reducing cavity 2 inside the panel 1, the panel 1 forms a box beam-like structure with bending resistance, which enhances the bending resistance of the photovoltaic module; by setting a weight-reducing cavity 2 inside the panel 1, it can also generate refraction when sunlight shines on it, improving the light absorption capacity of the module, thereby improving the module power; by setting a weight-reducing cavity 2 inside the panel 1, the weight of the photovoltaic module is reduced, and the transportation cost and installation difficulty are also reduced due to the reduction in the weight of the panel 1.

[0026] In practical applications, the photovoltaic module panel 1 with the weight-reduction cavity 2 exhibits numerous advantages. For example, in the construction of large-scale photovoltaic power plants, the reduced weight of panel 1 reduces wear and tear on transport vehicles during transportation, while increasing the number of panels 1 that can be transported in a single trip, significantly improving transportation efficiency. During installation, the lighter panel 1 is easier to handle, reducing the investment of manpower and resources, and lowering safety risks during installation. Therefore, the presence of the weight-reduction cavity 2 also helps reduce the overall weight of panel 1, making the entire device lighter and easier to transport, install, and operate without compromising the structural strength of panel 1.

[0027] For small-scale distributed photovoltaic (PV) power generation systems, such as residential rooftop PV, the advantages of this panel type 1 are equally evident. Its lower weight puts less stress on the roof, allowing for the installation of PV modules on a wider range of roof structures, thus broadening its application scope. Furthermore, its enhanced light absorption capacity allows for increased power generation efficiency within limited space, providing more clean energy for homes.

[0028] In future development, with the continuous advancement of photovoltaic technology, the structure of the weight-reducing cavity 2 in this photovoltaic module panel 1 is expected to be further optimized. For example, through more precise calculations and design, the shape and distribution of the weight-reducing cavity 2 can be adjusted to maximize its bending resistance and light absorption capacity while reducing weight. Simultaneously, the combined use with other novel photovoltaic materials can be explored, such as employing special reflective materials within the weight-reducing cavity 2 to further enhance light refraction and absorption, thereby driving photovoltaic modules to achieve higher levels of performance and cost-effectiveness.

[0029] The presence of the weight-reducing cavity 2 helps to reduce the overall weight of the panel 1, which is crucial in some applications with strict weight requirements, such as certain equipment components in the aerospace field.

[0030] In some embodiments, see Figure 1 and Figure 2 As shown, multiple weight-reducing cavities 2 are spaced apart along the length of panel 1. The weight-reducing cavities 2 are parallel to the long side of panel 1 and extend through the sides where the two short sides of panel 1 are located. Because panel 1 experiences the most significant bending along its long side, the weight-reducing cavities 2 are designed between the two short sides to improve the bending resistance of panel 1 along its long side. This is because the center of panel 1 experiences the greatest stress when bending along its long side, and a larger weight-reducing cavity 2 can better adapt to the stress distribution at this location, thereby further improving the overall bending resistance of panel 1 along its long side.

[0031] In some embodiments, see Figure 1 and Figure 2As shown, the weight-reducing cavity 2 is located between two adjacent battery strings, and the width of the weight-reducing cavity 2 is no greater than the distance between the two adjacent battery strings. The perforation structure must be designed in the middle of the gap between the battery strings, and the length of the triangle must not be greater than the width of the gap between the battery strings, usually around 1 mm. This improves the module's anti-bowing ability without obstructing the battery strings, thus making full use of the internal space.

[0032] Meanwhile, the shape and size of the weight-reducing cavity 2 have also been carefully designed. In some embodiments, the cross-sectional profile of the weight-reducing cavity 2 is triangular, and this shape has been proven to have the strongest resistance to bending.

[0033] The cross-section of the weight-reducing cavity 2 can also be circular, trapezoidal, rectangular, or other shapes. In this application, the weight-reducing cavity 2 is a through hole disposed in the panel 1 and parallel to the long side of the panel 1. The weight-reducing cavity 2 can also be a closed cavity distributed in the panel 1. Moreover, the size or width of the weight-reducing cavity 2 does not necessarily have to be uniform. For example, the weight-reducing cavity 2 near the center of the panel 1 is relatively larger.

[0034] In some embodiments, see Figure 2 As shown, the triangle is an equilateral triangle. It has been verified that this equilateral triangle shape has the strongest bending resistance and can also refract sunlight, improving the light absorption capacity of the module and thus increasing the module power. Figure 2 In the triangle, 'a' represents the path of the sunlight rays that refract after hitting the triangle.

[0035] In some embodiments, see Figure 2 As shown, the vertex of the triangle is close to the light-receiving surface 3 of panel 1 exposed to the atmosphere, and the base of the triangle is parallel to the light-receiving surface 3 of panel 1 and close to the inner side of panel 1 facing away from the light-receiving surface 3. This not only reduces the weight of the module itself and enhances its bending resistance, but also refracts sunlight when it shines on it, improving the module's light absorption capacity and thus increasing the module's power.

[0036] In some embodiments, see Figure 2As shown, the distance from the vertex of the triangle to the light-receiving surface 3 is greater than the distance from the base of the triangle to the inner side. Since the thickness of panel 1 is generally around 3.5mm, which is relatively thin, the light-receiving surface 3 of panel 1, being exposed after the weight-reducing cavity 2 is installed inside, is directly subjected to the forces of wind, rain, snow, and other uncontrollable heavy objects. If the distance from the vertex of the weight-reducing cavity 2 to the light-receiving surface 3 is too small, there is a risk of the weight-reducing cavity 2 being punctured, affecting the power and lifespan of the photovoltaic module. Therefore, in actual manufacturing, the distance from the vertex of the triangle to the light-receiving surface 3 is 0.2mm or more, while the base of the triangle, relying on the internal solar cells 4 and encapsulation layer, is not affected by external forces and can be smaller, for example, 0.1-0.15mm. This method maintains the overall structural strength and bending resistance.

[0037] In some embodiments, panel 1 is tempered glass. Tempering is a key step in improving the strength of the glass. The glass is heated to approximately 700°C in a horizontal tempering furnace, and then rapidly and uniformly cooled with cold air, causing compressive stress to form on the surface and tensile stress to form inside, thereby significantly improving the glass's bending and impact resistance. After this treatment, the strength of the glass can be increased to 4 to 5 times that of ordinary glass, providing long-term protection for photovoltaic cells.

[0038] In some embodiments, a sealing strip (not shown in the figure) is provided on the side of the panel 1 to seal the weight reduction cavity 2, so as to prevent external impurities and dust from entering the weight reduction cavity 2.

[0039] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0040] Based on the same inventive concept, this application also provides a photovoltaic module, see [link to relevant documentation]. Figure 3 As shown, the structure includes a panel 1, a front encapsulation layer, a battery cell 4, a back encapsulation layer, and a backplate 5, which are stacked in sequence. After lamination, an aluminum alloy frame is added, and a junction box is installed on the backplate 5.

[0041] Verification has shown that using this type of panel can reduce the overall weight of photovoltaic modules by 5%; increase the overall module power by 1 watt; significantly improve the bending problem of the modules; and greatly improve quality issues such as microcracks.

[0042] The encapsulation material used in this application can be ethylene-vinyl acetate (EVA) or polyolefin elastomer (POE). The function of the encapsulation layer is to bond the glass, solar cells, and backsheet, isolate moisture and oxygen, and prevent battery corrosion. Among them, POE has better weather resistance and is suitable for double-glass modules or harsh environments.

[0043] EVA, as a hot melt adhesive, plays a crucial role in photovoltaic modules. It is primarily responsible for firmly bonding tempered glass to the photovoltaic cells, enhancing not only the structural stability of the module but also ensuring excellent light transmittance. EVA film contains a cross-linking agent, enabling a cross-linking reaction at a curing temperature of 150°C, forming a stable adhesive layer through extrusion molding. Its thickness typically ranges from 2 to 8 millimeters, with commonly used thicknesses being 46 millimeters and 5 millimeters.

[0044] In solar cell modules, EVA film not only serves as an adhesive and sealant but is also crucial to the quality and lifespan of the solar cells. Therefore, EVA film used for module encapsulation must meet a series of stringent performance indicators, including curing conditions, light transmittance, degree of crosslinking, peel strength, temperature resistance, and resistance to ultraviolet light and heat aging.

[0045] As the core of solar photovoltaic modules, photovoltaic cells' primary function is to convert sunlight into electricity. In the market, mainstream photovoltaic cells include crystalline silicon solar cells and thin-film solar cells. Crystalline silicon cells, despite their relatively low equipment cost, are favored due to their high photoelectric conversion efficiency and suitability for outdoor sunlight power generation. Thin-film solar cells, while having higher equipment costs, also hold a place in the market due to their low power consumption, low cost, and excellent performance in low-light environments.

[0046] Backsheets play multiple roles in photovoltaic modules, including sealing, insulation, and waterproofing. To ensure the longevity of photovoltaic modules, backsheet materials such as TPT and TPE must possess excellent aging resistance. It is thanks to the protection of the backsheet that photovoltaic modules can better resist the ravages of aging and corrosion.

[0047] The frame is typically made of anodized aluminum alloy. Aluminum alloy frames play a crucial role in photovoltaic modules, serving not only to protect the power generation system of the solar panels but also to provide both sealing and support. Their superior strength and corrosion resistance enable photovoltaic modules to effectively withstand the damage of the external environment, thus ensuring their longevity and durability.

[0048] The main functions of the mounting frame for solar modules are fourfold. First, it protects the edges of the laminated module glass from damage caused by external factors. Second, combined with silicone edging, the frame further enhances the module's sealing performance, ensuring it is waterproof and dustproof. Third, the frame significantly improves the overall mechanical strength of the solar module, making it more stable and durable. Finally, it simplifies the transportation and installation process of the solar modules, enabling efficient and convenient installation, whether as individual units or in a photovoltaic array. During installation, holes are typically drilled at appropriate locations on the frame, and bolts are used to secure it to the corresponding holes on the solar module bracket, or a special clamping block is used to press it onto the module frame for fixation.

[0049] Junction boxes are designed to protect the entire power generation system. Through their sealing and waterproofing features, junction boxes ensure the safety of the leads from the photovoltaic modules, thereby guaranteeing the stability of the system during operation. The core component within the junction box—the diode—must be selected based on the characteristics of the solar cells within the module to ensure optimal protection.

[0050] In the production of battery modules, multiple factors must be considered when selecting junction boxes to ensure module performance and efficiency. These include basic parameters such as junction box dimensions, power handling capacity, operating current, and operating voltage, as well as the junction box's contact resistance and heat dissipation performance. Furthermore, the forward voltage drop, junction temperature, and thermal resistance of the bypass diodes within the junction box are also important factors that cannot be ignored during the selection process.

[0051] Silicone, a commonly used sealing material, is widely used to bond solar panels to solar frames, as well as at the junction of modules and junction boxes.

[0052] In the manufacturing of battery modules, two types of silicone sealant are typically used. The first is a neutral, single-component silicone sealant, specifically designed for bonding and sealing the modules to aluminum profile frames and junction boxes. This adhesive exhibits excellent room-temperature neutral curing properties, rapid curing, and allows for module surface cleaning within 3 hours, ensuring production efficiency. Simultaneously, its good sealing properties and adhesion to various materials enable the modules to possess excellent resistance to mechanical vibration and external impacts.

[0053] Another option is a two-component silicone thermally conductive adhesive, specifically designed for junction box potting. This silicone incorporates advanced silicone synthesis technology, offering not only room temperature curing but also maintaining rubber elasticity over a wide temperature range (−60~200℃), exhibiting excellent electrical and thermal conductivity. Furthermore, its waterproof, moisture-proof, chemical-resistant, yellowing-resistant, and weather-resistant properties allow it to adhere well to most plastics, rubbers, nylons, and other materials, ensuring the long-term stability and durability of the junction box.

[0054] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A panel for photovoltaic modules, characterized in that, A weight-reducing cavity (2) is provided inside the panel (1), and the weight-reducing cavity (2) passes through the two opposite sides of the panel (1); The weight reduction cavity (2) is disposed between two adjacent battery strings inside, and the width of the weight reduction cavity (2) is not greater than the distance between the two adjacent battery strings.

2. The photovoltaic module panel as described in claim 1, characterized in that, Multiple weight-reducing cavities (2) are provided at intervals along the length of the panel (1). The weight-reducing cavities (2) are parallel to the long side of the panel (1) and penetrate the two short sides of the panel (1).

3. The photovoltaic module panel as described in claim 1, characterized in that, The cross-sectional profile of the weight-reducing cavity (2) is triangular.

4. The photovoltaic module panel as described in claim 3, characterized in that, The triangle is an equilateral triangle.

5. The photovoltaic module panel as described in claim 3, characterized in that, The vertex of the triangle is close to the light-receiving surface (3) of the panel (1) exposed to the atmosphere, and the base of the triangle is parallel to the light-receiving surface (3) of the panel (1) and close to the inner side of the panel (1) facing away from the light-receiving surface (3).

6. The photovoltaic module panel as described in claim 5, characterized in that, The distance from the vertex of the triangle to the light-collecting surface (3) is greater than the distance from the base of the triangle to the inner surface.

7. The photovoltaic module panel as described in claim 1, characterized in that, The panel (1) is made of tempered glass.

8. The photovoltaic module panel as described in claim 1, characterized in that, The side of the panel (1) is provided with a sealing strip for sealing the weight reduction cavity (2).

9. A photovoltaic module, characterized in that, Including the photovoltaic module panel as described in any one of claims 1-8.

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