Photovoltaic module and application

Abstract

The application provides a photovoltaic module and application, and relates to the technical field of photovoltaic. Specifically, the photovoltaic module comprises a front plate layer, a first encapsulation adhesive film layer, a cell string layer, a second encapsulation adhesive film layer, a heat dissipation back plate layer and a sealing frame. The first encapsulation adhesive film layer and the second encapsulation adhesive film layer comprise boron nitride fillers. The cell string layer comprises a plurality of cell pieces, and a heat-conducting silica gel strip is arranged between any adjacent cell pieces, and the heat-conducting silica gel strip is connected with the heat dissipation back plate layer. The heat dissipation back plate layer comprises a base layer, an aluminum foil net heat-conducting layer and a waterproof layer which are connected in sequence. The sealing frame comprises a sealing groove and a heat-conducting groove, and the heat-conducting groove is connected with the aluminum foil net heat-conducting layer. The photovoltaic module has the beneficial effects of significantly improved heat dissipation efficiency, reduced risk of hidden cracks, improved sealing performance, prolonged service life and the like, and can meet the requirements of high performance and high durability.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, and more specifically, to a photovoltaic module and its application. Background Technology

[0002] The mainstream technology in photovoltaic module encapsulation currently involves stacking a front panel (such as tempered glass), an encapsulating film (such as ethylene-vinyl acetate copolymer EVA), a core layer of battery strings, an optional encapsulating film, and a backsheet (such as TPT / KPK). This is then laminated under specific temperature and pressure using a laminator, and finally, an aluminum alloy frame and junction box are installed. In this process, the battery strings are connected in series with solder ribbons, and a certain gap is left between the cells. The encapsulating film melts and fills the gaps between the cells during lamination, achieving adhesion between the layers. Based on this mainstream encapsulation process, to address the problem of reduced power generation efficiency due to heat accumulation inside the photovoltaic module during long-term outdoor operation, existing technologies typically employ two solutions: one is to optimize the cell grid design to reduce series resistance; the other is to add heat dissipation patterns to the backsheet surface. However, these heat dissipation measures are all passive, requiring heat to be conducted to the outside through multiple layers of media such as the encapsulating film and backsheet, resulting in a long heat conduction path and low efficiency.

[0003] On the other hand, there is a significant difference in the coefficient of thermal expansion between the cell strings and the encapsulating film inside the module. When the ambient temperature or the module's operating temperature changes periodically, the expansion and contraction of the two are inconsistent. Furthermore, since the encapsulating film is tightly bonded to the cell strings after lamination, this difference in deformation will create mutual constraints at the interface, resulting in concentrated mechanical stress in structurally weak areas such as the edges of the cells. When this repeated stress exceeds the fracture strength of the cell strings themselves, it will cause microcracks invisible to the naked eye to form in the cells, thereby damaging the structural integrity of the cells, blocking the current transmission path, and causing irreversible accelerated degradation of the photovoltaic module's output power.

[0004] Furthermore, photovoltaic module encapsulation solutions also involve bonding and sealing structures, typically using silicone as the mainstream material. However, during long-term outdoor service, silicone is subjected to multiple environmental stresses, including ultraviolet radiation, high and low temperature cycling, and moisture erosion. Its molecular structure gradually undergoes cross-linking chain breakage, hardening, or cracking, i.e., aging. Once the silicone sealing layer cracks or debonds, it's equivalent to destroying the module's original airtight barrier, allowing moisture from the external environment to seep into the module through the gaps. This infiltrated moisture can electrochemically corrode the grid lines or solder strips on the surface of the cell string, leading to decreased conductivity or even open circuits. It can also corrode the electrode structure inside the cell string, ultimately causing a significant drop in module power and, in severe cases, even safety issues such as insulation failure.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] The primary objective of this invention is to provide a photovoltaic module that addresses the technical problems of existing photovoltaic modules, such as insufficient heat dissipation performance, mechanical structural defects caused by insufficient thermal expansion coefficient, and poor long-term performance of silicone sealing.

[0007] A second objective of this invention is to provide a photovoltaic device.

[0008] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: A photovoltaic module includes a front panel layer, a first encapsulating film layer, a cell string layer, a second encapsulating film layer, and a heat dissipation backsheet layer stacked in sequence, and also includes a sealing frame encapsulating the edge of the photovoltaic module; The photovoltaic module satisfies the following characteristics (a) to (d): (a) The first encapsulating film layer and the second encapsulating film layer include boron nitride filler; (b) The battery string layer includes a plurality of battery cells, and a thermally conductive silicone strip is provided between any adjacent battery cells, and the thermally conductive silicone strip is connected to the heat dissipation backplate layer; (c) The heat dissipation backplate layer comprises a base layer, an aluminum foil thermal conductive layer and a waterproof layer connected in sequence; (d) The sealing frame includes a sealing groove and a heat-conducting groove, and the heat-conducting groove is connected to the aluminum foil mesh heat-conducting layer.

[0009] In one embodiment, the first encapsulating film layer and the second encapsulating film layer further include a POE film substrate, wherein the boron nitride filler is uniformly dispersed in the POE film substrate.

[0010] In one embodiment, the mass ratio of the boron nitride filler to the first encapsulating film layer is 8% to 12%, and / or the mass ratio of the boron nitride filler to the second encapsulating film layer is 8% to 12%.

[0011] In one embodiment, the thicknesses of the first encapsulating film layer and the second encapsulating film layer are independently selected from 0.45 mm to 0.55 mm.

[0012] In one embodiment, the spacing between any two adjacent battery cells is 4.2 mm to 5.5 mm.

[0013] In one embodiment, the thermal conductivity of the thermally conductive silicone strip is ≥1.5 W / (m²). K).

[0014] In one embodiment, the thermal conductivity of the first encapsulating film layer and the second encapsulating film layer is 0.28 W / (m²). K)~0.4W / (m K).

[0015] In one embodiment, the aluminum foil mesh thermal conductive layer has a mesh size of 150-250 mesh.

[0016] In one embodiment, the thickness of the aluminum foil thermal conductive layer is 0.08 mm to 0.2 mm.

[0017] In one embodiment, the sealing frame further includes an aluminum alloy outer frame, and the sealing groove and the heat-conducting groove are sequentially fitted inside the aluminum alloy outer frame.

[0018] In one embodiment, the sealing groove includes a butyl rubber layer and a silicone rubber layer stacked sequentially, and the heat-conducting groove is made of copper or a copper alloy.

[0019] In one embodiment, the method for manufacturing the photovoltaic module includes: sequentially laying materials of the front panel layer, the first encapsulating film layer, the cell string layer, the second encapsulating film layer and the heat dissipation backsheet layer, and then laminating them; The lamination temperature is 120℃~150℃, the external pressure is 0.8MPa~1.0MPa, and the holding time is 20min~45min.

[0020] A photovoltaic device includes the aforementioned photovoltaic module.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention effectively solves the problem of low heat dissipation efficiency in existing photovoltaic modules. It designs an active heat dissipation structure where various heat dissipation components work together to effectively shorten the heat conduction path, quickly dissipating the heat generated by the solar cells. This improves the power generation efficiency of the photovoltaic module in high-temperature environments and slows down the aging of the encapsulation materials. Simultaneously, this invention also alleviates the problem of thermal stress concentration between the solar cells and the encapsulation film, reducing the risk of microcracks in the solar cells and improving the structural stability and lifespan of the module. Furthermore, this invention optimizes the frame sealing structure of the photovoltaic module, enhancing waterproof sealing, preventing moisture intrusion, and improving the weather resistance of the photovoltaic module.

[0022] The photovoltaic module encapsulation method of the present invention can be adapted to existing photovoltaic module production lines. Only the encapsulant material and layout tooling need to be adjusted, without the need for large-scale equipment modification, and it has industrialization and promotion value. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 A structural schematic diagram of the photovoltaic module of the present invention is provided. Detailed Implementation

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0026] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In addition, the terms "first," "S1," "(a)," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] Existing photovoltaic modules have the following three main defects in terms of encapsulation: (1) Low heat dissipation efficiency: The heat dissipation of existing modules relies on the heat conduction of the medium. The heat generated by the working cells cannot be quickly dissipated, and the photoelectric conversion efficiency of the cells decreases at high temperatures. For example, the efficiency of monocrystalline silicon cells decreases by about 0.4% for every 1°C increase in temperature. Long-term high temperature will also accelerate the aging and yellowing of the encapsulant film, shortening the service life of the modules.

[0028] (2) Structural stress concentration: The difference in thermal expansion coefficient between the battery string and the film is large. During temperature cycling, stress concentration is likely to occur at the edge of the battery cell, which increases the risk of microcracks in the battery cell and exacerbates the power decay of the module after microcracks.

[0029] (3) Insufficient waterproof sealing: The existing frame and the main body of the module rely on silicone for sealing. Silicone is prone to aging and cracking due to long-term exposure to ultraviolet rays and high and low temperature cycles, which leads to water vapor intrusion into the module and causes problems such as cell corrosion and solder ribbon oxidation.

[0030] A first aspect of the present invention is to provide a photovoltaic module, comprising a front panel layer, a first encapsulating film layer, a cell string layer, a second encapsulating film layer and a heat dissipation backplate layer stacked sequentially, and further comprising a sealing frame encapsulating the edge of the photovoltaic module.

[0031] It is understood that the functional elements / components described above in this invention all conform to the corresponding basic functions in the art. Specifically, the front panel layer is located on the outermost layer of the module, directly facing sunlight, and mainly serves to transmit light, resist weathering, provide mechanical protection, and self-clean. It needs to have high light transmittance to maximize the sunlight entering the battery layer, while also possessing excellent impact resistance, UV aging resistance, and low water vapor transmittance to protect the internal batteries from external environmental damage. The first and second encapsulating film layers are used to connect different layers and, to a certain extent, serve as optical coupling, electrical insulation, stress buffering, and electrical insulation, filling gaps to prevent air bubbles and water vapor intrusion. Simultaneously, through their good light transmittance and refractive index matching, they improve light utilization. The battery string layer is the core power generation unit, composed of multiple photovoltaic cells connected in series or parallel via interconnecting strips. It is responsible for converting solar energy into DC power and is a key component determining the reliability and electrical performance of the module. The heat dissipation backsheet layer is located on the outermost back of the module and mainly serves as mechanical support, electrical insulation, moisture protection, heat dissipation, and weather protection. It needs to have good thermal conductivity to aid heat dissipation and high reflectivity to reflect light passing through the cell gaps back to the cells, improving module efficiency. The sealing frame encloses the photovoltaic module, primarily serving as structural support, mechanical protection, waterproof sealing, and installation fixation. It also enhances the overall rigidity of the photovoltaic module and its resistance to wind pressure and snow loads, preventing delamination of the laminate edges or moisture intrusion from the sides. Furthermore, it provides mounting points for connection to the support system, ensuring the structural integrity and safety of the module during long-term outdoor use.

[0032] In a preferred embodiment, the front panel layer comprises ultra-clear tempered glass; in some embodiments, the thickness of the front panel layer includes 3.0mm to 4.0mm, including but not limited to any one or any two of 3.1, 3.2, 3.4, 3.5, 3.6, 3.8, 3.9, and 4.0 (mm); in some embodiments, an anti-reflective coating is deposited on the surface of the ultra-clear tempered glass to further improve light utilization.

[0033] Meanwhile, the photovoltaic module satisfies the following characteristics (a) to (d), which will be described in detail below.

[0034] (a) The first encapsulating film layer and the second encapsulating film layer include boron nitride filler.

[0035] In a preferred embodiment, the first encapsulating film layer and the second encapsulating film layer further include a POE film substrate, and the boron nitride filler is uniformly dispersed in the POE film substrate. In some embodiments, the thermal conductivity of the POE film substrate is 0.12 W / (m²). K)~0.22W / (m K), those skilled in the art can select any commercially available conventional or unconventional POE substrate based on this performance parameter. In this invention, no restrictions are placed on the specific synthetic monomers, components, or synthesis processes of the POE film substrate. In some embodiments, the thermal conductivity of the first encapsulating film layer and the second encapsulating film layer is 0.28 W / (m²). K)~0.4W / (m K), that is, based on the boron nitride filler, the thermal conductivity of the adhesive film layer can be effectively improved.

[0036] In a preferred embodiment, the boron nitride filler is present in a mass ratio of 8% to 12% of the first encapsulating film layer, and / or the boron nitride filler is present in a mass ratio of 8% to 12% of the second encapsulating film layer. In some more preferred embodiments, the boron nitride filler is present in 10% of both the first and second encapsulating film layers. At this point, the thermal conductivity and flexibility of the film are optimally balanced, satisfying both thermal conductivity requirements and compatibility with existing lamination processes, while preventing film embrittlement and delamination.

[0037] In a preferred embodiment, the boron nitride filler is in sheet form. Sheet-shaped boron nitride has a larger specific surface area and better thermal conductivity continuity, enabling the formation of continuous thermal channels in the POE film substrate, significantly improving the thermal conductivity of the film. In some more preferred embodiments, the boron nitride filler has the following dimensions: sheet diameter 5μm~20μm, thickness 0.5μm~2μm, and uniform particle size distribution (D50 is 8μm~12μm). This size ensures that the boron nitride filler is uniformly dispersed in the POE film substrate, without agglomeration or affecting the film's light transmittance and adhesion, while also fully utilizing its thermal conductivity, consistent with the film's thermal conductivity of 0.28W / (m²). K)~0.4W / (m The parameters of K) match.

[0038] In a preferred embodiment, the thickness of the first encapsulating film layer and the second encapsulating film layer is 0.45mm to 0.55mm, including but not limited to any one or any two of the following values: 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.52, 0.53, 0.54, and 0.55 (mm).

[0039] (b) The battery string layer includes a plurality of battery cells, and a thermally conductive silicone strip is provided between any adjacent battery cells, and the thermally conductive silicone strip is connected to the heat dissipation backplate layer.

[0040] In a preferred embodiment, the spacing between any two adjacent battery cells is 4.2mm to 5.5mm, including but not limited to any one or any two of the following values: 4.2, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, and 5.5 (mm).

[0041] In a preferred embodiment, the thermal conductivity of the thermally conductive silicone strip is ≥1.5 W / (m²). K); It is understood that those skilled in the art can use any conventional or unconventional silicone resin or silicone rubber products that meet the above thermal conductivity effect as the thermally conductive silicone strip of the present invention, or can cut or process conventional thermally conductive silicone sheets, thermally conductive pads, etc. to obtain the strip-shaped thermally conductive silicone strip.

[0042] In one preferred embodiment, the thermally conductive silicone strip is in direct contact with the battery cell. This contact arrangement further shortens the heat conduction path from the battery cell to the silicone strip, improving heat dissipation efficiency. Simultaneously, the silicone strip itself has a certain degree of flexibility, which can buffer thermal stress between the battery cell and the heat sink backplate, further reducing the risk of microcracks in the battery cell, and preventing wear or damage to the surface of the battery cell. In another preferred embodiment, the distance between the thermally conductive silicone strip and the battery cell is 0.01mm to 0.8mm. In this case, no contact is required between the thermally conductive silicone strip and the battery cell, avoiding stress or wear caused by contact between the silicone strip and the battery cell. The above two embodiments have different performance emphases, and those skilled in the art can adapt or adjust the performance selection accordingly.

[0043] (c) The heat dissipation backplate layer includes a base layer, an aluminum foil thermal conductive layer and a waterproof layer connected in sequence.

[0044] In a preferred embodiment, the total thickness of the heat dissipation backplate layer is 0.3mm to 0.6mm. This thickness ensures both the mechanical strength and flexibility of the heat dissipation backplate, while also taking into account the requirements for thermal conductivity and lightweight design.

[0045] In a preferred embodiment, the thickness of the base layer is 0.15mm to 0.3mm, including but not limited to any one or any two of 0.15, 0.2, 0.25, and 0.3 (mm); the thickness of the waterproof layer is 0.08mm to 0.15mm, including but not limited to any one or any two of 0.08, 0.1, 0.12, and 0.15 (mm). The combination of the thicknesses of the base layer and the waterproof layer can provide a stable mounting carrier for the aluminum foil mesh heat-conducting layer while ensuring protective performance.

[0046] In a preferred embodiment, the aluminum foil thermal conductive layer is embedded between the base layer and the waterproof layer, and the aluminum foil thermal conductive layer extends to the outer edge of the photovoltaic module, and the aluminum foil thermal conductive layer is connected to the thermal conductive groove of the sealing frame.

[0047] In a preferred embodiment, the base layer is made of PET, and the waterproof layer is made of PVDF.

[0048] In one preferred embodiment, the aluminum foil mesh in the thermal conductive layer is made of pure aluminum or aluminum alloy; in some embodiments, the aluminum foil mesh is made of aluminum alloys of grades such as 1060, 1100, and 8011.

[0049] In a preferred embodiment, the aluminum foil mesh in the thermally conductive layer has a mesh size of 150-250 mesh, more preferably 200 mesh; in some embodiments, the thickness of the thermally conductive layer is 0.08 mm to 0.2 mm, including but not limited to any one or any two of 0.08, 0.1, 0.12, 0.14, 0.15, 0.16, 0.18, and 0.2 (mm). It is understood that the specifications of the above-mentioned aluminum foil mesh layer ensure thermal conductivity without affecting the flexibility of the backplate.

[0050] (d) The sealing frame includes a sealing groove and a heat-conducting groove, and the heat-conducting groove is connected to the aluminum foil mesh heat-conducting layer.

[0051] In a preferred embodiment, the sealing frame further includes an aluminum alloy outer frame, with the sealing groove and the heat-conducting groove sequentially fitted inside the aluminum alloy outer frame. In some embodiments, a plurality of heat sinks are provided on the outer side of the aluminum alloy outer frame. The heat sinks may adopt shapes such as heat dissipation fins or heat dissipation scales, or adopt geometric structures such as sheet-like, columnar, needle-like, or wavy shapes, extending outward from the substrate surface to enhance the outward heat conduction effect of the sealing frame.

[0052] In a preferred embodiment, the sealing groove includes a butyl rubber layer and a silicone rubber layer stacked sequentially, wherein the silicone rubber layer is located close to the heat-conducting groove side. In some embodiments, for the sealing groove, the thickness of the butyl rubber layer is 0.3mm to 0.5mm, including but not limited to any one or any two of 0.3, 0.4, and 0.5 (mm); the thickness of the silicone rubber layer is 0.2mm to 0.4mm, including but not limited to any one or any two of 0.2, 0.3, and 0.4 (mm). This thickness combination ensures both the waterproof and moisture-proof performance of the double-layer seal and is compatible with the frame fitting process, avoiding excessive sealant overflow or insufficient sealing.

[0053] In one preferred embodiment, the heat-conducting groove is made of copper or a copper alloy; in some embodiments, the thermal conductivity of the heat-conducting groove is ≥380 W / (m²). K); It is understood that the grooved copper alloy strip utilizes its high thermal conductivity to form an efficient local heat conduction channel; at the same time, the heat transmitted by the aluminum foil mesh thermal conductive layer is quickly and efficiently conducted to the outside of the sealing frame, reducing heat accumulation in the edge area and avoiding reliability risks such as accelerated aging of the encapsulation film and hot spots on the battery cell caused by local overheating.

[0054] like Figure 1 The diagram shows a structural schematic of a photovoltaic module obtained by combining the above-described preferred embodiments.

[0055] In a preferred embodiment, the method for preparing the photovoltaic module includes: sequentially laying the materials of the front panel layer, the first encapsulating film layer, the cell string layer, the second encapsulating film layer and the heat dissipation backsheet layer, and then laminating them; the lamination temperature is 120℃~150℃, the external pressure is 0.8MPa~1.0MPa, and the pressure holding time is 20min~45min. In some optional embodiments, the characteristic parameters of the lamination include: temperature including but not limited to any one or any two of 120, 125, 130, 135, 140, 145, 150 (°C); external pressure including but not limited to any one or any two of 0.8, 0.82, 0.85, 0.88, 0.9, 0.92, 0.95, 0.98, 1.0 (MPa); and holding time including but not limited to any one or any two of 20, 25, 30, 35, 40, 45 (min).

[0056] A second aspect of the present invention is to provide a photovoltaic device; it is understood that, provided that the photovoltaic module as described in the first aspect is included, any type of photovoltaic device may be an embodiment of this aspect; in some embodiments, the photovoltaic device may include other photovoltaic modules not described in the first aspect; the photovoltaic device includes, but is not limited to, large-scale ground power plants, distributed generation systems, or integrated applications of photovoltaics with specific application scenarios.

[0057] Example S1: Front panel pretreatment; the ultra-clear tempered glass (3.2mm) is cleaned, dried, and coated with an anti-reflective film.

[0058] S2: Film preparation; Boron nitride filler was mixed into the POE film raw material at a mass ratio of 10%, and extruded into a modified POE film with a thickness of 0.5 mm (thermal conductivity increased to 0.3 W / (m)). K).

[0059] S3: Battery string arrangement; Connect the battery cells in series with solder strips, set the spacing between any two adjacent battery cells to 6mm, and place a circular cross-section thermal conductive silicone strip (5mm in diameter) in the middle of this spacing. The axis of the thermal conductive silicone strip is parallel to the edge of the battery cell, and a 0.5mm gap is reserved between the two sides of the thermal conductive silicone strip and the edges of the two adjacent battery cells to ensure that the silicone strip does not contact the edge of the battery cell.

[0060] S4: Heatsink backplate assembly; complete the assembly following these steps: S4-1: Select a PET base layer with a thickness of 0.2mm, clean and dry its surface to remove surface oil and impurities; S4-2: Lay a 0.1mm thick, 200-mesh 1060 grade aluminum foil mesh (aluminum foil mesh heat-conducting layer) flat on the PET base surface, and use a hot-pressing bonding method (hot-pressing temperature 120℃, pressure 0.3MPa, holding pressure for 10min) to fix the aluminum foil mesh on the PET base, ensuring that the aluminum foil mesh is flat, wrinkle-free, and does not detach, and that the edge of the aluminum foil mesh extends 5mm beyond the edge of the PET base for subsequent connection with the heat-conducting groove of the sealing frame; S4-3: Select a 0.1mm thick PVDF waterproof layer and apply it evenly to the surface of the aluminum foil mesh using a coating process. After coating, place it in a drying oven and dry it at 80℃ for 20 minutes to ensure that the PVDF waterproof layer is tightly bonded to the aluminum foil mesh and PET base layer, ultimately forming a heat dissipation backplate with a total thickness of 0.4mm (0.2mm PET base layer + 0.1mm aluminum foil mesh + 0.1mm PVDF waterproof layer). After assembly, check that the surface of the backplate is free of damage and bubbles.

[0061] S5: Layer assembly; sequentially lay the front plate layer obtained in S1, the adhesive film obtained in S2, the battery string layer after layout in S3, the adhesive film obtained in S2, and the heat dissipation backplate layer obtained in S4 on the laminator pad, ensuring that each layer is aligned.

[0062] S6: Lamination and Encapsulation; Set the laminator parameters: heat to 140℃, pressure 0.9MPa, hold for 30 minutes, and allow to cool naturally to room temperature after lamination.

[0063] S7: Frame Assembly; An aluminum alloy sealed frame pre-equipped with external heat dissipation fins (specifications: length matches the frame, width 15mm, thickness 2mm, quantity 4 fins per meter of frame, evenly spaced). The sealing groove of the frame is first filled with butyl rubber (0.4mm thick), then silicone strips (0.3mm thick) are applied. A copper heat-conducting strip (rectangular cross-section, 8mm width, 3mm thickness, material T2 copper, thermal conductivity ≥380W / (m²)) is placed in the heat-conducting groove. K); then the S6 laminated component body is embedded into the assembled frame, ensuring that the copper heat-conducting strip and the aluminum foil mesh extending from the heat dissipation backplate are in close contact. The frame is pressed using a pressing device (pressure 1.2MPa), and the sealant is cured (curing temperature 80℃, curing time 30min) to complete the frame assembly.

[0064] S8: Post-processing; install junction boxes, test component electrical and sealing performance, and complete the finished product.

[0065] The photovoltaic modules prepared in the above embodiments were tested, and the following performance results were obtained: (i) Significantly improved heat dissipation efficiency: The embodiment uses an active heat dissipation path of "thermal conductive silicone strip, heat dissipation backplate aluminum foil mesh, frame thermal conductive strip, and heat dissipation fins" so that the heat of the solar cells can be directly discharged to the outside during operation. According to the test, at an ambient temperature of 35°C, the solar cell operating temperature of the embodiment is 9±1°C lower than that of the traditional module, and the average power generation efficiency is improved by 4±1%.

[0066] (ii) Reduced risk of microcracks: The coefficient of thermal expansion of the modified POE film is closer to that of the solar cell, wherein the coefficient of thermal expansion of the modified POE film (containing 10% boron nitride filler by mass) is controlled at 80×10⁻⁶. -6 / ℃~100×10 -6 The coefficient of thermal expansion of the solar cell (conventional crystalline silicon solar cell) is 2.8 × 10⁻⁶ °C. -6 / ℃~3.2×10 -6 / ℃, the difference in thermal expansion coefficients between the two is significantly reduced, and the spacing between the cells is increased and filled with flexible thermally conductive silicone strips, which alleviates stress concentration during temperature cycling and reduces the rate of microcracks by more than 60%.

[0067] (III) Improved sealing performance: The double-layer sealing structure (butyl rubber and silicone) of the sealing frame replaces the traditional single silicone seal, and the waterproof rating of the frame is improved to IP68. After the damp heat test (85℃ / 85%RH, 1000h), the power attenuation of the module is ≤2%, which is far better than the 5% of the traditional module.

[0068] (iv) Extended service life: With the combined effects of improved heat dissipation and stress relief, the design service life of the components is extended from 25 years to 30 years, and the power attenuation rate during long-term operation is reduced.

[0069] Although the present invention has been illustrated and described with specific embodiments, it should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; those skilled in the art should understand that modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein, without departing from the spirit and scope of the present invention; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention; therefore, this means that all such substitutions and modifications that fall within the scope of the present invention are included in the appended claims.

Claims

1. A photovoltaic module, characterized in that, It includes a front panel layer, a first encapsulating film layer, a battery string layer, a second encapsulating film layer, and a heat dissipation backplate layer stacked in sequence, and also includes a sealing frame encapsulating the edge of the photovoltaic module; The photovoltaic module satisfies the following characteristics (a) to (d): (a) The first encapsulating film layer and the second encapsulating film layer include boron nitride filler; (b) The battery string layer includes a plurality of battery cells, and a thermally conductive silicone strip is provided between any adjacent battery cells, and the thermally conductive silicone strip is connected to the heat dissipation backplate layer; (c) The heat dissipation backplate layer comprises a base layer, an aluminum foil thermal conductive layer and a waterproof layer connected in sequence; (d) The sealing frame includes a sealing groove and a heat-conducting groove, and the heat-conducting groove is connected to the aluminum foil mesh heat-conducting layer.

2. The photovoltaic module according to claim 1, characterized in that, The first encapsulation film layer and the second encapsulation film layer further include a POE film substrate, wherein the boron nitride filler is uniformly dispersed in the POE film substrate.

3. The photovoltaic module according to claim 1, characterized in that, The mass ratio of the boron nitride filler to the first encapsulating film layer is 8% to 12%, and / or the mass ratio of the boron nitride filler to the second encapsulating film layer is 8% to 12%.

4. The photovoltaic module according to claim 1, characterized in that, The thicknesses of the first encapsulating film layer and the second encapsulating film layer are independently selected from 0.45mm to 0.55mm.

5. The photovoltaic module according to claim 1, characterized in that, The spacing between any two adjacent solar cells is 4.2mm to 5.5mm.

6. The photovoltaic module according to claim 1, characterized in that, The thermal conductivity of the thermally conductive silicone strip is ≥1.5W / (m). K); And / or, the thermal conductivity of the first encapsulating film layer and the second encapsulating film layer is 0.28 W / (m²). K)~0.4W / (m K).

7. The photovoltaic module according to claim 1, characterized in that, In the aluminum foil thermal conductive layer, the aperture of the aluminum foil mesh is 150 mesh to 250 mesh; And / or, the thickness of the aluminum foil thermal conductive layer is 0.08mm~0.2mm.

8. The photovoltaic module according to claim 1, characterized in that, The sealing frame also includes an aluminum alloy outer frame, and the sealing groove and the heat-conducting groove are sequentially fitted into the inner side of the aluminum alloy outer frame; And / or, the sealing groove includes a butyl rubber layer and a silicone rubber layer stacked sequentially, and the heat-conducting groove is made of copper or a copper alloy.

9. The photovoltaic module according to claim 1, characterized in that, The method for manufacturing the photovoltaic module includes: sequentially laying the materials of the front panel layer, the first encapsulating film layer, the cell string layer, the second encapsulating film layer and the heat dissipation backsheet layer, and then laminating them; The lamination temperature is 120℃~150℃, the external pressure is 0.8MPa~1.0MPa, and the holding time is 20min~45min.

10. A photovoltaic device, characterized in that, Including the photovoltaic module as described in any one of claims 1 to 9.

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