Photovoltaic module

Abstract

A photovoltaic module, comprising reflective films each provided with: a first insulating region extending from a first end to a second end of a photovoltaic module in a first direction; and a second insulating region extending from a third end to a fourth end of the photovoltaic module in a second direction. In this way, the first insulating region insulates and isolates two rows of battery cells in the second direction, so that even if the reflective film is in short circuit with the adjacent battery cells, a short circuit between the adjacent cells in the second direction can be avoided due to the existence of the first insulating region. In addition, the second insulating region insulates and isolates the battery strings in the first direction, so that a short circuit between the battery strings at two ends of the photovoltaic module in the first direction can be avoided. According to the photovoltaic module, the risk of short circuit between the battery cells can be reduced, and the output power of the photovoltaic module is improved.

Description

Photovoltaic panels

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to Chinese patent application number 202311449647.8, filed on November 2, 2023, and entitled “Photovoltaic Module”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to the field of photovoltaic technology, and in particular to photovoltaic modules. Background Art

[0004] Photovoltaic modules, also known as solar panels or photovoltaic cells, are the core components of photovoltaic power generation systems that convert sunlight radiation into direct current (DC) electricity.

[0005] In a related technology, bifacial photovoltaic modules consist of double-sided glass and multiple rows of solar cell strings nestled between them. The backside of the module can also receive scattered and reflected light from the environment to generate electricity, resulting in higher overall power generation efficiency. In particular, bifacial double-glass modules, with their backside encapsulated in glass, are resistant to long-term outdoor degradation, exhibit strong corrosion resistance, and are resistant to salt spray and wind and sand. These superior performance makes them the preferred module solution for a growing number of ground-based power plants.

[0006] Summary of the Invention

[0007] In view of the above shortcomings of the related art, the purpose of the present disclosure is to provide a photovoltaic module to solve the technical problem of low output power of the photovoltaic module in the related art.

[0008] A first aspect of the present disclosure provides a photovoltaic assembly, comprising:

[0009] Double-sided glass;

[0010] At least two columns of battery strings are disposed between the double-sided glass and arranged along a first direction, each of the battery strings comprising a plurality of battery cells arranged along a second direction, the first direction being perpendicular to the second direction;

[0011] A reflective film is provided between two adjacent rows of cells along the second direction;

[0012] The reflective film is provided with:

[0013] a first insulating region extending from a first end to a second end of the photovoltaic assembly along the first direction;

[0014] A second insulating region extends from the third end to the fourth end of the photovoltaic assembly along the second direction.

[0015] In some embodiments, the reflective film is provided with the second insulating region between every two adjacent columns of solar cells along the first direction.

[0016] In some embodiments, in the battery string, two adjacent battery cells along the second direction are connected by a welding ribbon; the second insulating region is specifically provided between two inner welding ribbons of two adjacent columns of battery strings.

[0017] In some embodiments, in the battery string, two adjacent battery cells along the second direction are connected by a welding ribbon; and among the multiple second insulating regions distributed along the first direction, the distance between two adjacent second insulating regions is less than or equal to the distance between the two inner welding ribbons of two adjacent columns of battery strings along the first direction.

[0018] In some embodiments, the second insulating region is provided at least at one location between two inner welding ribbons of the two outermost columns of battery strings along the first direction.

[0019] In some embodiments, the second insulating regions are respectively provided at the positions of two inner welding strips of the two outermost columns of battery strings along the first direction.

[0020] In some embodiments, the reflective film includes an adhesive layer, a support body and a reflective layer connected in sequence along the second direction, and the adhesive layer is connected to the back glass; the first insulating area and the second insulating area are formed in the reflective film in a cut-off area at least located in the reflective layer.

[0021] In some embodiments, the depth of the cut-off region is greater than or equal to the thickness of the light reflecting layer.

[0022] In some embodiments, the depth of the cut-off region is less than or equal to the sum of the thicknesses of the support body and the light reflecting layer.

[0023] In some embodiments, the reflective film is provided with at least two first insulating regions arranged along the second direction.

[0024] As described above, in the disclosed embodiments, a photovoltaic module is provided in which the first insulating region insulates and separates two rows of cells along the second direction. This prevents short circuits between adjacent cells along the second direction due to the presence of the first insulating region. Furthermore, the second insulating region insulates and separates the cell strings along the first direction, preventing short circuits between the cell strings at both ends of the photovoltaic module along the first direction. Therefore, the photovoltaic module of this embodiment can reduce the risk of short circuits between cells and increase the output power of the photovoltaic module. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG1 is a cross-sectional view of a photovoltaic module provided by an embodiment of the present disclosure.

[0026] FIG2 is a back view of a photovoltaic module provided by an embodiment of the present disclosure.

[0027] FIG3 is one of the top views of a reflective film in a photovoltaic module provided by an embodiment of the present disclosure.

[0028] FIG4 is one of the cross-sectional views of a reflective film in a photovoltaic module provided by an embodiment of the present disclosure.

[0029] FIG5 is a second top view of a reflective film in a photovoltaic module provided by an embodiment of the present disclosure.

[0030] FIG6 is one of partial rear views of a photovoltaic module provided by an embodiment of the present disclosure.

[0031] FIG7 is a second partial rear view of a photovoltaic module provided by an embodiment of the present disclosure.

[0032] FIG8 is a third partial rear view of a photovoltaic module provided by an embodiment of the present disclosure.

[0033] FIG9 is a fourth partial rear view of a photovoltaic module provided by an embodiment of the present disclosure.

[0034] FIG10 is a second cross-sectional view of a reflective film in a photovoltaic module provided by an embodiment of the present disclosure.

[0035] 11-12 are cross-sectional views of the reflective film shown in FIG. 10 during the production stage.

[0036] FIG13 is a third cross-sectional view of a reflective film in a photovoltaic module provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0037] The following describes the embodiments of the present disclosure using specific examples. Those skilled in the art can easily understand the other advantages and benefits of the present disclosure from the information disclosed herein. The present disclosure can also be implemented or applied to systems using different specific embodiments. The details of the present disclosure can also be modified or altered based on different viewpoints and application systems without departing from the spirit of the present disclosure. It should be noted that the embodiments and features of the embodiments in the present disclosure can be combined with each other unless they conflict.

[0038] The following is a detailed description of the embodiments of the present disclosure with reference to the accompanying drawings so that those skilled in the art can easily implement the present disclosure. The present disclosure can be embodied in many different forms and is not limited to the embodiments described herein.

[0039] In the present disclosure, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and integrate different embodiments or examples described in the present disclosure, as well as features of different embodiments or examples, unless otherwise contradictory.

[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the context of this disclosure, "plurality" means two or more, unless otherwise specifically defined.

[0041] Although not defined differently, all terms used herein, including technical and scientific terms, have the same meanings as those generally understood by those skilled in the art to which this disclosure belongs. Terms defined in commonly used dictionaries are additionally interpreted as having meanings consistent with relevant technical literature and the current message. Unless otherwise defined, they should not be overly interpreted as ideal or highly formalized meanings.

[0042] In related technologies, if the back of a bifacial photovoltaic module uses fully transparent materials (glass or transparent backplane), light will directly pass through the cells and strings, thereby reducing the optical utilization of the front side and resulting in a reduction in the power of the front module.

[0043] In related technology, a reflective film is applied to the back glass at locations corresponding to the string and cell spacing. When light passes through the gaps between cells and between strings and reaches the reflective film, it is reflected at a specific angle onto the front glass, where it is reflected back onto the cell surface, thereby increasing the output power of the front panel. To increase the reflectivity of light, the reflective surface of this reflective film is typically sputtered with a continuous reflective layer.

[0044] However, the reflective layer has certain conductive properties. When different solar cells use a reflective film, the adhesive film between the reflective film and the solar cells and / or welding ribbons becomes thinner after lamination in some areas, or the welding ribbons pierce the adhesive film, resulting in insufficient insulation between the reflective layer on the reflective film and the solar cells and / or welding ribbons, causing electron tunneling or overlapping short circuit anomalies, thereby reducing the power output of the photovoltaic module.

[0045] In view of the reasons for the problems existing in the related art, the embodiments of the present disclosure propose an improved photovoltaic module. By forming an insulating area in the reflective film, the problem of overlap between the reflective layer on the reflective film and the solar cells and / or welding strips is reduced, thereby achieving the purpose of improving the output power of the photovoltaic module.

[0046] Specifically, an embodiment of the present disclosure provides a photovoltaic assembly, as shown in Figures 1 and 2, comprising:

[0047] Double-sided glass, including front glass 1 and back glass 2;

[0048] At least two columns of battery strings 3 (as shown in FIG2 ) are disposed between the front glass 1 and the back glass 2 and arranged along a first direction AA′. Each battery string 3 includes a plurality of battery cells 30 arranged along a second direction BB′. The first direction AA′ is perpendicular to the second direction BB′.

[0049] The reflective film 4 is disposed between two adjacent rows of solar cells 30 along the second direction BB′.

[0050] As shown in FIG3 , the reflective film 4 is provided with:

[0051] a first insulating region 41 extending from a first end to a second end of the photovoltaic module along the first direction AA′;

[0052] A second insulating region 42 extends from the third end to the fourth end of the photovoltaic module along the second direction BB′.

[0053] In the disclosed embodiment, the first insulating region 41 insulates and separates the two rows of cells 30 along the second direction BB' (i.e., the longitudinal direction in FIG. 3 ). Thus, even if a short circuit occurs between the reflective film 4 and adjacent cells 30, the presence of the first insulating region 41 prevents short circuits between adjacent cells 30 along the second direction BB'. Furthermore, the second insulating region 42 insulates and separates the cell strings 3 along the first direction AA' (i.e., the transverse direction in FIG. 4 ), preventing short circuits between the cell strings 3 at both ends of the photovoltaic module along the first direction AA'. Therefore, the photovoltaic module of this embodiment can reduce the risk of short circuits between cells and increase the output power of the photovoltaic module.

[0054] Specifically, as shown in Figure 4 , the reflective sheeting 4 generally has a three-layer structure, comprising an adhesive layer 43, a support 44, and a reflective layer 45, which are sequentially connected along the second direction BB'. The adhesive layer 43 is typically made of a hot melt adhesive such as ethylene vinyl acetate copolymer (EVA) or polyolefin elastomer (POE), and serves to bond the sheeting to the back glass 2 (see Figure 1 ). The support 44 is typically made of a structurally strong material such as polyethylene terephthalate (PET), and the reflective layer 45 is prefabricated on the support 44.

[0055] As shown in Figure 1 , the reflective film 4 is interposed between the back glass 2 and the back adhesive film 5 , with the reflective surface of the reflective film 4 (reflective layer 45 shown in Figure 4 ) facing the cell 30. The reflective film 4 is insulated from the soldering ribbon 6 and / or the cell 30 by the back adhesive film 5 . Specifically, both ends of the reflective film 4 along the second direction BB' overlap with the cell 30 .

[0056] As shown in Figure 2, a whole strip of reflective film 4 is affixed to the back glass 2 (as shown in Figure 1). This strip of reflective film 4 extends through several cell strings, such as cell strings 3a, 3b, 3c, and 3d in Figure 2. In one scenario, along the first direction AA', the cell strings 3a and 3d on the outside of the photovoltaic module are subjected to greater pressure during the lamination process, which can easily cause the adhesive film to be squeezed out, resulting in a reduction in the insulation thickness between the reflective film 4 and the soldering ribbon 6 and / or the cell sheets. Furthermore, during the soldering process, the soldering ribbon 6 may contain protrusions such as tin beads, which can pierce the adhesive film and degrade insulation performance. If insulation degradation occurs simultaneously on different cell strings 3, such as when the soldering ribbon 6 of both cell strings 3a and 3d makes electrical contact with the reflective layer 45 (as shown in Figure 3), forming two contact points L1 and L2, the reflective film 4 prevents an electrical loop from forming between the two contact points L1 and L2 due to the second insulating region 42 (as shown in Figure 3), thus preventing short circuit anomalies and reducing the output power of the photovoltaic module.

[0057] In another case, for two adjacent cells in the same cell string 3, such as the first and second cells in cell string 30c, at position I1, the reflective film 4 is easily short-circuited with the soldering ribbon 6 below it, and the reflective film 4 at position I2 may be short-circuited with the cell below it due to insufficient insulation thickness. At this time, the presence of the first insulating region 41 (as shown in FIG. 3 ) can prevent the positive and negative electrodes of these two cells from short-circuiting.

[0058] In the embodiment of the present disclosure, as shown in FIG. 3 , the first insulating region 41 is continuous along the first direction AA′.

[0059] In another embodiment, as shown in FIG5 , the reflective film 4 ′ is provided with two first insulating regions 41 ′ arranged along the second direction BB′, which can further reduce the risk of short circuits. In other embodiments, the reflective film can also be provided with three or more first insulating regions along the second direction, which is not limited here.

[0060] In the disclosed embodiment, as shown in FIG6 , the reflective film 60 is provided with a second insulating region 62 between each two adjacent columns of battery strings 6 along the first direction AA′. This ensures effective insulation between each battery cell 61. The distance between two adjacent second insulating regions 62 is equal to the sum of the length of the battery cell 61 along the first direction AA′ and the distance between two adjacent battery cells 61.

[0061] In the disclosed embodiment, two adjacent cells 61 along the second direction BB' are connected via a soldering ribbon 63. The second insulating region 62 is specifically disposed between the two inner soldering ribbons 63 of two adjacent columns of cell strings 6. When applying the reflective film 60, the second insulating region 62 on the reflective film 60 is identified using a camera, laser, or other means, and the center of the second insulating region 62 is positioned between the two inner soldering ribbons 63 of the two cell cells 61.

[0062] In another embodiment of the present disclosure, as shown in Figure 7, two adjacent cells 70 along the second direction BB' are connected by a soldering ribbon 71. Multiple second insulating regions 72 are distributed along the first direction AA', and the distance between two adjacent second insulating regions 72 is less than or equal to the distance between the inner two soldering ribbons 71 of two adjacent columns of cell strings 7 along the first direction AA'. In this case, when placing the reflective film 73, it is not necessary to identify the second insulating regions 72 on the reflective film 73. Random placement can ensure that a second insulating region 72 exists between the inner two soldering ribbons 71 of two adjacent cells 70.

[0063] In one embodiment of the present disclosure, as shown in FIG8 , a second insulating region 81 is provided at least one location along the first direction AA′ between two inner soldering ribbons 80 of the two outermost columns of battery strings 8. Specifically, the second insulating region 81 is provided at a mid-length of the reflective film 82 along the first direction AA′.

[0064] In another embodiment of the present disclosure, as shown in FIG9 , a second insulating region 92 is provided at the inner two solder ribbons 91 of the two outermost columns of battery strings 90 along the first direction AA'. In this case, when placing the reflective film 93, there is no need to identify the second insulating region 92 on the reflective film 93. Random placement can ensure that a second insulating region 92 exists between the inner two solder ribbons 91 of the two outermost battery cells 94.

[0065] In these two embodiments, since a second insulating region is provided between the two inner welding ribbons of the two outermost rows of cell strings, even if the two outermost rows of cell strings are squeezed due to stress concentration, no conductive loop is formed with the reflective film.

[0066] As shown in FIG10 , the first insulating region 101 and the second insulating region 102 are formed in the cut-off region of at least the reflective layer 103 of the reflective film 100. In this case, the depth h1 of the first insulating region 101 and the second insulating region 102 is equal to the thickness of the reflective layer 103. This is because the reflective layer 103 in the reflective film 100 functions as a conductor, and therefore, the insulating cut-off region can be formed by only etching through the thickness of the reflective layer 103.

[0067] In the embodiment of the present disclosure, the first insulating region 101 and / or the second insulating region 102 can be formed when coating the reflective layer 103. Specifically, as shown in FIG11 , a mask 105 is first formed on the support 104;

[0068] As shown in FIG12 , a reflective layer 103 is coated, and the reflective layer 103 covers the support 104 and the mask 105 ;

[0069] Afterwards, the mask is removed to form the structure shown in FIG. 10 .

[0070] In another embodiment, the cut-off area corresponding to the first insulating area and / or the second insulating area can also be removed after the reflective layer is coated. In this case, the reflective layer on the surface can be removed by laser cutting, physical cutting, etc.

[0071] As shown in FIG. 13 , the depth h2 of the cut-off region formed by the first insulating region 111 and / or the second insulating region 112 is greater than the thickness of the light reflecting layer 113 .

[0072] Therefore, the depth of the cut-off region formed by the first insulating region and / or the second insulating region is greater than or equal to the thickness of the light reflecting layer.

[0073] As shown in FIG13 , the depth h2 of the cut-off region formed by the first insulating region 111 and / or the second insulating region 112 is less than or equal to the thickness h3 of the reflective film 110. This is because the reflective film 110 will need to withstand a certain winding force later on, so the entire reflective film 110 is not cut through at this time to provide the required winding force.

[0074] The above embodiments are merely illustrative of the principles and effects of this disclosure and are not intended to limit this disclosure. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this disclosure. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical concepts disclosed herein shall be covered by the claims of this disclosure.

Claims

1. A photovoltaic module, characterized in that: include: Double-sided glass; At least two columns of battery strings are disposed between the double-sided glass and arranged along a first direction, each of the battery strings comprises a plurality of battery cells arranged along a second direction, and the first direction is perpendicular to the second direction; A reflective film is arranged between two adjacent rows of cells along the second direction; The reflective film is provided with: a first insulating region extending from a first end to a second end of the photovoltaic assembly along the first direction; A second insulating region extends from the third end to the fourth end of the photovoltaic component along the second direction.

2. The photovoltaic module according to claim 1, characterized in that: The reflective film is provided with the second insulating region between every two adjacent columns of battery cells along the first direction.

3. The photovoltaic module according to claim 2, characterized in that: In the battery string, two battery cells adjacent to each other along the second direction are connected by a welding strip; the second insulating area is specifically arranged between two inner welding strips of two adjacent columns of battery strings.

4. The photovoltaic module according to claim 1, characterized in that: In the battery string, two adjacent battery cells along the second direction are connected by a welding strip; among the multiple second insulating regions distributed along the first direction, the distance between two adjacent second insulating regions is less than or equal to the distance between the two inner welding strips of two adjacent columns of battery strings along the first direction.

5. The photovoltaic module according to claim 1, characterized in that: The second insulating area is provided at at least one position between two inner welding strips of the two outermost columns of battery strings along the first direction.

6. The photovoltaic module according to claim 5, characterized in that: The second insulating areas are respectively arranged at the positions of the two inner welding strips of the two outermost columns of battery strings along the first direction.

7. The photovoltaic module according to claim 1, characterized in that: The reflective film comprises an adhesive layer, a support body and a reflective layer connected in sequence along the second direction, the adhesive layer is connected to the back glass; the first insulating area and the second insulating area are formed in the reflective film in a cut-off area at least located in the reflective layer.

8. The photovoltaic module according to claim 7, characterized in that: The depth of the cut-off area is greater than or equal to the thickness of the light reflecting layer.

9. The photovoltaic module according to claim 8, characterized in that: The depth of the cut-off area is less than or equal to the thickness of the reflective film.

10. The photovoltaic module according to claim 1, characterized in that: The reflective film is provided with at least two first insulating regions arranged along the second direction.

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