Lightweight flexible solar module

Abstract

The utility model discloses a light flexible solar energy assembly, which comprises a back plate, a back packaging layer, a battery layer, a front packaging layer and a transparent front plate which are laminated and packaged in sequence from bottom to top, the packaging layers are used for packaging the back plate, the battery layer and the transparent front plate into a whole, the battery layer comprises a battery array, framework strips and frame glue, the battery array is composed of a plurality of battery pieces, and the framework strips are connected with the frame glue. Conductive adhesive is used between the battery pieces to form a circuit, the two framework strips are located on the outer sides of the two long edges of the battery array respectively, the frame adhesive is used for fixing the framework strips and sealing the outer edge of the battery array, and the framework strips and the frame adhesive can be repeatedly curled. The mechanical strength and the reliability of the light flexible solar assembly are improved, the service life of the assembly is prolonged, the problems of excessive deformation of the solar cell assembly and subfissure of the cell pieces in the production, carrying, installation and use processes can be effectively reduced, the water vapor barrier property is improved in the outdoor use process, and the power attenuation is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of photovoltaic solar cells, and in particular relates to a lightweight flexible solar energy component. Background Art

[0002] Lightweight flexible solar panels are composed of solar cells, front baffles, adhesive films, back panels, junction boxes, and lead wires. They can be repeatedly curled or bent in other forms without causing obvious physical, electrical performance damage or visual damage. They have significant characteristics such as "light", "thin", "flexible", and "bendable". They can be used in distributed power station scenes and special scenes such as industrial and commercial color steel tile roofs, flat roofs, and residential tile houses. However, most flexible components use polymer transparent materials instead of traditional tempered glass, which has poor mechanical strength and is prone to excessive bending during production, transportation, installation, and use. The cells inside the components are subject to internal stress, which will cause hidden cracks and damage, and permanently reduce the output power. In particular, flexible components are fixed by back silicone or foam glue. During installation, you must press the components to obtain a higher installation strength. If the pressing force is not properly grasped, the installation will be unstable or the cells will be damaged. The installation is difficult and the construction requirements are high. In addition, because the flexible component material is too soft and lacks support, it is easy for the components to be excessively bent and stressed without being noticed during production, transportation, installation, and other uses. It is also easy to deform during long-term use. For example, when applied to color steel tiles or tile roofs, it needs to be laid horizontally, that is, the long side of the lightweight flexible solar module is perpendicular to the tile ridge of the color steel tile or tile roof, and the color steel tile or tile roof is uneven. Therefore, only the part of the lightweight flexible solar module that is attached to the tile ridge (i.e., the convex edge) has support, and most of it is suspended in the groove between two adjacent tile ridges without support, and its own support force is poor. Over time, it will deform in the lateral area of ​​the module, that is, the module suspended between the tile ridges is concave. After the module is deformed, it is easy to accumulate dust, and it is difficult to get regular and effective washing and maintenance on the roof, which will cause hot spot effects, and even cause hidden cracks in the battery due to internal stress. Compared with traditional solar photovoltaic modules, flexible solar modules have poor water resistance. During outdoor use, water vapor easily penetrates into the module from the edge, and the water resistance rate shows a downward trend year by year. The water vapor that penetrates from the side of the module will gradually increase over time and cause irreversible performance degradation to the battery, thereby causing a decrease in module efficiency. In general, the reliability risks of flexible components further limit the promotion and application of this component.

[0003] In order to solve the problem of low mechanical strength of the components, the existing technology adopts ultra-thin photovoltaic glass, high-strength composite materials or adds an impact-resistant layer to the front plate layer to enhance the mechanical strength, weather resistance and flexibility of the structure and improve the ability of the components to resist hidden cracks. However, these solutions have problems such as high cost, complex structure and process, which further limit the promotion and application of flexible components. Flexible components are limited by the choice of packaging materials. Water vapor can easily penetrate the front plate, the side of the component and the film to contact the battery cell. The water resistance rate decreases year by year during long-term use in outdoor environments. In order to solve the problem of poor water resistance of the components, solutions such as improving the polymer front plate material and adding a water-blocking film layer structure can be adopted. However, these solutions are difficult to solve the problem of water vapor penetrating from the side of the component, and the overall water resistance rate of the flexible component still needs to be improved. Some studies have set a mesh high-strength skeleton in the battery layer and embedded a powdered water-absorbing material at multiple sites on the surface of the skeleton to improve the mechanical strength and weather resistance of the component, alleviate the problem of water vapor penetration of the component, and increase the service life of the component. However, the current important development trend of flexible modules is flexible shingled modules. The mesh skeleton is not only not suitable for the close arrangement of cells inside the shingled module (the cells of the shingled module overlap each other front and back, leaving no gaps between the cells), but also increases the weight of the lightweight flexible module. In addition, the powdered water-absorbing material is easy to fly to the surface of the cell due to the electrostatic effect during lamination, and the water-absorbing material itself is unstable under the long-term action of water vapor, oxygen and ultraviolet rays, which affects the water absorption effect and even decomposes other substances, causing damage to the module. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a lightweight flexible solar panel with a simple structure and which can effectively improve the supporting strength under the premise of being lightweight and flexible.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] A lightweight flexible solar panel comprises a backplane, a rear encapsulation layer, a battery layer, a front encapsulation layer and a transparent front panel which are laminated and encapsulated in sequence from bottom to top. The front encapsulation layer and the rear encapsulation layer are used to encapsulate the transparent front panel, the battery layer and the backplane into a whole. The battery layer comprises a battery array, a skeleton bar and a frame glue. The battery array is composed of a plurality of battery cells. A circuit is formed between the battery cells through conductive glue. Two skeleton bars are respectively located outside the two long sides of the battery array. The frame glue is used to fix the skeleton bars and seal the outer edge of the battery array. Both the skeleton bars and the frame glue can be repeatedly curled.

[0007] In the above-mentioned lightweight flexible solar energy component, preferably, the R angle at which the skeleton bar can be bent is greater than the minimum bending angle at which the performance of the lightweight flexible solar energy component does not suffer a loss.

[0008] In the above-mentioned lightweight flexible solar energy module, preferably, the skeleton bar is a PVB skeleton bar, a PVC skeleton bar, a carbon fiber skeleton bar, a nylon skeleton bar or an ABS skeleton bar.

[0009] In the above-mentioned lightweight flexible solar energy module, preferably, the cross section of the skeleton bar is circular, and both ends of the skeleton bar are smoothly chamfered.

[0010] In the above-mentioned lightweight flexible solar panel, preferably, the frame glue is a butyl rubber adhesive.

[0011] In the above-mentioned lightweight flexible solar panel, preferably, the frame glue is butyl rubber frame sealant, polyisobutylene-modified butyl rubber frame sealant or polyisobutylene-modified butyl rubber frame sealant with integrated desiccant, and the desiccant is silica gel particles or molecular sieves.

[0012] In the above-mentioned lightweight flexible solar energy module, preferably, the battery array comprises a plurality of parallel battery strings, and the battery string is formed by a plurality of battery cells connected in series.

[0013] In the above-mentioned lightweight flexible solar module, preferably, the battery string is a shingled structure, which is composed of a number of battery cells overlapped in sequence front to back, and the overlapping parts of the battery cells are adhered with conductive glue to form a series circuit, and a plurality of the battery strings are arranged side by side, and the ends of adjacent battery strings are connected in parallel through conductive bus bars.

[0014] In the above-mentioned lightweight flexible solar panel, preferably, the conductive adhesive comprises a polymer matrix and conductive particles, the conductive particles are silver ions, and the polymer matrix is ​​an organic silicon polymer, an acrylate polymer, an epoxy polymer or an organic fluorine polymer.

[0015] Compared with the prior art, the advantages of the utility model are:

[0016] The lightweight flexible solar panel of the utility model uses conductive glue to form a circuit between the cells. Since the conductive glue has a certain elasticity, compared with the traditional welding strip, it can not only reduce the stress on the cell itself when the component is deformed, reduce the risk of hidden cracks, but also arrange the cells tightly, reduce internal resistance, and improve the conversion efficiency of the photovoltaic module; at the same time, a skeleton bar that can be repeatedly curled is arranged on the lateral outer side of the battery array, which can enhance the mechanical strength of the solar cell module and meet the needs of tightly arranging the cells inside the flexible solar cell module. The mesh skeleton in the prior art is not conducive to the tight arrangement of the internal batteries, and in comparison, the two lateral skeleton bars are more in line with the requirements of lightweight flexible solar panels. Usually, when installed, the width direction of the flexible solar panel overlaps with the ridge of the color steel tile or the aluminum square tube, and there is no need to set a supporting skeleton in the width direction, which is more conducive to controlling the overall weight of the component. In addition, frame glue is used to seal the edge area of ​​the battery layer. The frame glue is applied to the edge area of ​​the battery layer around the frame and the edge area of ​​the battery layer not covered by the frame. First, the high viscosity of the frame glue is used to fix the position of the frame strip to avoid the internal stress caused by squeezing the internal battery cells and causing internal cracks in the internal battery cells; second, the high sealing and water-blocking properties of the frame sealant are used to prevent water vapor from penetrating into the component from the edge position, thereby avoiding a decrease in component efficiency. The utility model uses frame glue to seal the edge of the battery layer to avoid the problems of difficult fixation and unstable properties of powdered water-absorbing materials used in the prior art. Through the above design, the mechanical strength and reliability of the lightweight and flexible solar module of the utility model are improved, thereby increasing the service life of the module, and can effectively reduce the problems of excessive deformation of solar cell modules and hidden cracks in the battery cells during production, transportation, installation, and use. During outdoor use, the water vapor barrier is improved and power attenuation is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of a lightweight flexible solar module according to a specific embodiment of the utility model.

[0018] Figure 2 It is a schematic diagram of the structure of the battery layer in a specific embodiment of the utility model.

[0019] Figure 3 It is a schematic structural diagram of a shingled assembly in a specific embodiment of the utility model.

[0020] Legend:

[0021] 1. Backplane; 2. Rear packaging layer; 3. Battery layer; 31. Battery array; 311. Battery cell; 312. Conductive glue; 32. Skeleton strip; 33. Frame glue; 4. Front packaging layer; 5. Transparent front plate. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with the accompanying drawings and specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0023] like Figure 1 As shown, this embodiment provides a lightweight flexible solar panel, including a back sheet 1, a rear encapsulation layer 2, a battery layer 3, a front encapsulation layer 4 and a transparent front sheet 5 which are laminated and encapsulated in sequence from bottom to top, and the rear encapsulation layer 2 and the front encapsulation layer 4 are used to encapsulate the back sheet 1, the battery layer 3 and the transparent front sheet 5 into a whole, as shown in FIG. Figure 2 As shown, the battery layer 3 includes a battery array 31, a skeleton bar 32 and a frame glue 33. The battery array 31 is composed of a number of battery cells 311 (such as crystalline silicon battery cells). Conductive glue 312 is used between the battery cells 311 to form a circuit. The two skeleton bars 32 are respectively located on the outside of the two long sides of the battery array 31. The frame glue 33 is used to fix the skeleton bars 32 and seal the outer edge of the battery array 31. The skeleton bars 32 and the frame glue 33 can be repeatedly curled.

[0024] The lightweight flexible solar module of this embodiment uses conductive glue 312 between the cells 311 to form a circuit. Since the conductive glue 312 has a certain elasticity, compared with the traditional welding strip, it can not only reduce the stress on the cell 311 itself when the module is deformed, reduce the risk of hidden cracks, but also arrange the cell 311 tightly, reduce internal resistance, and improve the conversion efficiency of the photovoltaic module; at the same time, a frame bar 32 that can be repeatedly curled is arranged on the outside of the cell array 31 in the horizontal direction (length direction), which can enhance the mechanical strength of the solar cell module and meet the needs of tightly arranging the cells inside the flexible solar cell module, such as the shingled module. The mesh frame in the prior art is not conducive to the tight arrangement of the internal cells, and in comparison, the two horizontal frame bars 32 are more in line with the requirements of lightweight flexible solar modules. Usually, when installed, the width direction of the flexible solar module overlaps with the ridge of the color steel tile or the aluminum square tube, and no support frame is required, which is also conducive to controlling the overall weight of the module. In addition, the edge area of ​​the battery layer 3 is sealed with a frame glue 33, and the frame glue 33 is applied to the edge area of ​​the battery layer 3 around the skeleton and the edge area of ​​the battery layer 3 not covered by the skeleton. First, the high viscosity of the frame glue 33 is used to fix the position of the skeleton strip 32 to avoid the internal stress caused by squeezing the internal battery cell 311 and causing the internal battery cell 311 to crack; second, the high sealing and water-blocking properties of the frame sealant are used to prevent water vapor from penetrating into the component from the edge position to avoid the decrease in component efficiency. The use of frame glue 33 to seal the edge of the battery layer 3 in this embodiment can avoid the problems of powdered water-absorbing materials being difficult to fix and unstable in properties in the prior art. The mechanical strength and reliability of the lightweight flexible solar module of this embodiment are improved, thereby increasing the service life of the module, and can effectively reduce the excessive deformation of the solar cell module and the problem of hidden cracks in the battery cell 311 during production, transportation, installation, and use. The water vapor barrier is improved during outdoor use and the power attenuation is reduced.

[0025] In this embodiment, the R angle at which the skeleton bar 32 can be bent is greater than the minimum bending angle at which the performance of the lightweight flexible solar module does not suffer a loss. A skeleton with a certain mechanical strength is placed in parallel in the transverse (i.e., lengthwise) outer area of ​​the battery array 31, which can not only ensure the soft property of the flexible solar module that can be repeatedly curled, but also enhance the mechanical strength of the module, so that the actual bendable R angle of the module is greater than the minimum bending angle at which the performance of the module does not suffer a loss, thereby avoiding the problem of hidden cracks in the battery cell 311 during the production, transportation, installation, and use of the module, and reducing the hot spot effect caused by the concave deformation problem after long-term use.

[0026] In this embodiment, the frame bar 32 is a PVB frame bar, a PVC frame bar, a carbon fiber frame bar, a nylon frame bar or an ABS frame bar. The frame bars of this type of material are moderately soft and hard, have good support and can be repeatedly curled, and are light in texture, meeting the requirements of lightweight flexible solar panels.

[0027] In this embodiment, the cross section of the skeleton strip 32 is circular, and both ends of the skeleton strip 32 are rounded and chamfered. Using a cylindrical skeleton and rounding both ends can make the skeleton evenly stressed during the lamination process and avoid the generation of bubbles.

[0028] In this embodiment, a lightweight flexible solar panel with a length, width and height of 2278 mm×1134 mm×2.5 mm is taken as an example. The preferred length of the skeleton bar 32 is 2200 mm to 2250 mm, the width is 25 mm to 50 mm, and the thickness is 2.5 mm.

[0029] In this embodiment, the frame glue 33 is a butyl rubber adhesive, specifically a polyisobutylene (PIB) modified frame sealant. This type of frame sealant has high viscosity and water resistance, and has a certain flexibility, which can enable the lightweight flexible solar panel to maintain a soft property that can be repeatedly curled.

[0030] In this embodiment, the frame glue 33 is a frame sealant with an integrated desiccant, specifically made of Quanex Edge Sealant product, this border sealant is a polyisobutylene butyl rubber adhesive containing a desiccant and can be co-extruded when used.

[0031] like Figure 3As shown, in this embodiment, the battery array 31 includes a plurality of parallel battery strings, each battery string is formed by a plurality of battery cells 311 connected in series, and further preferably, the battery string is a shingled structure, which is formed by a plurality of battery cells 311 overlapped in sequence, and the overlapped portions of the battery cells 311 are bonded with conductive glue 312 to form a series circuit, and a plurality of battery strings are arranged side by side, and the current directions of each battery column are the same, and the ends of adjacent battery strings are connected in parallel through conductive bus bars to form a parallel circuit. Specifically, the electrodes on the front and back sides of the battery cells 311 are flexibly connected by conductive glue 312 (that is, the electrode on the front side of the previous battery cell 311 is connected to the electrode on the back side of the next battery cell 311), and a plurality of battery cells 311 overlapped in front and back form a battery string of shingled structure, and a plurality of battery strings are embedded side by side between the skeleton bars 32, and finally the edge of the battery layer 3 is sealed by the frame glue 33. The type of battery cell 311 can preferably be crystalline silicon battery such as TOPCon, HJT or XBC, with preferred length and width dimensions of 183.5mm×45.5mm and thickness of 0.09mm~0.13mm. The battery cells 311 are combined in series to form a battery string, and the battery strings are connected in parallel through conductive bus bars to form a circuit.

[0032] This embodiment uses conductive glue 312 to flexibly connect the battery cells 311, which can reduce the stress generated when the component is deformed and improve the anti-hidden crack performance; the shingled structure is used with no battery cell spacing, which can increase the power density by about 2% compared with conventional components, effectively improving the power generation efficiency and power; the unique full-parallel circuit connection can reduce current loss and improve resistance to hot spot effects.

[0033] In this embodiment, the conductive adhesive 312 includes a polymer matrix and conductive particles. The conductive particles are silver ions, and the polymer matrix is ​​an organic silicon polymer, an acrylate polymer, an epoxy polymer, or an organic fluorine polymer.

[0034] Although the present invention has been disclosed as a preferred embodiment, it is not intended to limit the present invention. Any technician familiar with the art can use the above disclosed technical content to make many possible changes and modifications to the technical solution of the present invention without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention should fall within the scope of protection of the technical solution of the present invention.

Claims

1. A lightweight flexible solar panel, characterized in that: The invention comprises a back plate (1), a rear encapsulation layer (2), a battery layer (3), a front encapsulation layer (4) and a transparent front plate (5) which are laminated and encapsulated in sequence from bottom to top. The rear encapsulation layer (2) and the front encapsulation layer are used to encapsulate the back plate (1), the battery layer (3) and the transparent front plate (5) into a whole. The battery layer (3) comprises a battery array (31), a skeleton bar (32) and a frame glue (33). The battery array (31) is composed of a plurality of battery cells (311). The battery cells (311) form a circuit through the conductive glue (312). The two skeleton bars (32) are respectively located outside the two long sides of the battery array (31). The frame glue (33) is used to fix the skeleton bars (32) and seal the outer edge of the battery array (31). Both the skeleton bars (32) and the frame glue (33) can be repeatedly curled.

2. The lightweight flexible solar module according to claim 1, characterized in that: The R angle at which the skeleton bar (32) can be bent is greater than the minimum bending angle at which the performance of the lightweight flexible solar module does not suffer any loss.

3. The lightweight flexible solar module according to claim 2, characterized in that: The frame strip (32) is a PVB frame strip, a PVC frame strip, a carbon fiber frame strip, a nylon frame strip or an ABS frame strip.

4. The lightweight flexible solar module according to claim 1, characterized in that: The cross section of the frame bar (32) is circular, and both ends of the frame bar (32) are smoothly chamfered.

5. The lightweight flexible solar module according to claim 1, characterized in that: The frame glue (33) is a butyl rubber adhesive.

6. The lightweight flexible solar module according to claim 5, characterized in that: The frame glue (33) is butyl rubber frame sealant, polyisobutylene-modified butyl rubber frame sealant, or polyisobutylene-modified butyl rubber frame sealant with integrated desiccant.

7. The lightweight flexible solar module according to any one of claims 1 to 6, characterized in that: The battery array (31) comprises a plurality of parallel-connected battery strings, wherein the battery string is formed by connecting a plurality of battery sheets (311) in series.

8. The lightweight flexible solar module according to claim 7, characterized in that: The battery string is a shingled structure, which is formed by overlapping a plurality of battery sheets (311) in sequence, wherein the overlapping portions of the battery sheets (311) are adhered with conductive glue (312) to form a series circuit, and a plurality of battery strings are arranged side by side, and the ends of adjacent battery strings are connected in parallel via conductive bus bars.

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