Photovoltaic module

Abstract

The embodiment of the present application relates to the photovoltaic technical field, provide a kind of photovoltaic module, to improve the light utilization of the space that is not set cell piece is irradiated, to further improve the power of component. The photovoltaic module includes: multiple cell string groups arranged along a first preset direction;First bus unit, disposed between two adjacent cell string groups, the first bus unit includes multiple first bus bars arranged at intervals;Second bus unit, disposed along the first preset direction, located at the first position of the first side of cell string group, and located at the second side of cell string group at the end position;Second bus unit includes multiple second bus bars arranged at intervals;Multiple reflection structures, reflection structure is arranged on the surface of first bus bar and / or second bus bar.

Description

Technical Field

[0001] This application relates to the field of photovoltaic technology, and in particular to a photovoltaic module. Background Technology

[0002] In photovoltaic (PV) modules, the more light a solar cell receives, the more current and voltage it can generate, thus increasing the module's power output. Currently, besides the solar cells, there are other spaces within PV modules where no solar cells are installed. Light shining into these un-celled spaces cannot be effectively utilized by the cells, thus hindering further increases in module power. Utility Model Content

[0003] This application provides a photovoltaic module to improve the utilization rate of light illuminating a space without solar cells, thereby further increasing the module's power.

[0004] According to some embodiments of this application, one aspect of this application provides a photovoltaic module, including:

[0005] Multiple battery string groups are arranged along a first preset direction; the battery string group includes multiple battery strings arranged along a second preset direction; each battery string includes a first side and a second side arranged opposite to each other along the first preset direction; the first preset direction and the second preset direction intersect.

[0006] A first busbar unit is disposed between two adjacent battery string groups, and the first busbar unit includes a plurality of first busbars disposed at intervals;

[0007] The second busbar unit is disposed on the first side of the battery string group located at the first position and the second side of the battery string group located at the last position, arranged along the first preset direction; the second busbar unit includes a plurality of second busbars arranged at intervals;

[0008] Multiple reflective structures are disposed on the surface of the first busbar and / or the second busbar.

[0009] According to some embodiments of this application, the reflective structure can be separately disposed from the first busbar and / or the second busbar.

[0010] According to some embodiments of this application, the reflective structure includes an insulating layer, a support layer, and a reflective layer stacked sequentially. The insulating layer is in contact with and fixed to the first busbar and / or the second busbar, and the reflective layer is used to partially reflect light incident on the reflective layer to the adjacent battery string.

[0011] According to some embodiments of this application, the insulating layer is an insulating adhesive layer, which is bonded and fixed to the first busbar and / or the second busbar.

[0012] According to some embodiments of this application, the width of the reflective structure disposed on the surface of the second busbar is greater than or equal to the width of the second busbar.

[0013] According to some embodiments of this application, the reflective structure disposed on the surface of the second busbar extends toward the adjacent battery string from the side close to it.

[0014] According to some embodiments of this application, the reflective structure disposed on the surface of the second busbar covers a portion of the gap between the second busbar and the adjacent battery string, as well as a portion of the side of the second busbar near the adjacent battery string.

[0015] According to some embodiments of this application, the distance between the second busbar and the adjacent battery string is 2mm to 3mm; the distance between the reflective structure disposed on the surface of the second busbar and the side near the adjacent battery string is 0.2mm to 3mm.

[0016] According to some embodiments of this application, the reflective structure disposed on the surface of the second busbar is located away from the side of the adjacent battery string and does not extend beyond the edge of the second busbar.

[0017] According to some embodiments of this application, the width of the reflective structure disposed on the surface of the first busbar is greater than the width of the first busbar.

[0018] According to some embodiments of this application, the reflective structure disposed on the surface of the first busbar extends to the adjacent battery strings on both sides.

[0019] According to some embodiments of this application, the reflective structure disposed on the surface of the first busbar covers a portion of the gap between the first busbar and the battery strings on both adjacent sides, as well as a portion of the side of the first busbar near the battery strings on both adjacent sides.

[0020] According to some embodiments of this application, the distance between the first busbar and the adjacent battery string is 2mm to 3mm; the distance between the reflective structure disposed on the surface of the first busbar and the side close to the adjacent battery string is 0.2mm to 3mm.

[0021] According to some embodiments of this application, the support layer includes at least one protrusion arranged along the first preset direction, the longitudinal section of the protrusion being triangular in shape; the triangle includes a base, and a first side and a second side respectively connected to the base; the reflective layer is disposed on the surface of the protrusion facing away from the insulating layer.

[0022] According to some embodiments of this application, the included angle between the first side and the second side is 90 degrees to 120 degrees.

[0023] According to some embodiments of this application, in the reflective structure disposed on the surface of the second busbar, the first side is close to the adjacent battery string, the second side is away from the adjacent battery string, and the angle between the first side and the bottom side is 22 degrees to 32.5 degrees.

[0024] According to some embodiments of this application, in the reflective structure disposed on the surface of the second busbar, the first side is close to the adjacent battery string, the second side is away from the adjacent battery string, and the length of the first side is greater than or equal to the length of the second side.

[0025] According to some embodiments of this application, in the reflective structure disposed on the surface of the first busbar, the length of the first side and the length of the second side are the same.

[0026] According to some embodiments of this application, the height of the protrusion is 10µm to 30µm.

[0027] This application provides a photovoltaic module in which a reflective structure is provided on the surface of one side of the first busbar and / or the second busbar. When light shines on the reflective structure, part of the light is reflected by the reflective structure to the adjacent cell string, thereby improving the utilization rate of the light shining on the first busbar and / or the second busbar, and thus further improving the module power. Attached Figure Description

[0028] One or more embodiments are illustrated by way of example with corresponding pictures in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this application or in the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of a photovoltaic module's cell string assembly provided in an embodiment of this application;

[0030] Figure 2 A schematic diagram of a photovoltaic module provided in an embodiment of this application, comprising a battery string group, a first busbar unit, and a second busbar unit;

[0031] Figure 3A schematic diagram of a photovoltaic module provided in this application embodiment, comprising a battery string group, a first combiner unit, a second combiner unit, and a reflective structure;

[0032] Figure 4 for Figure 3 A schematic diagram of a cross-section along the C1C2 direction;

[0033] Figure 5 for Figure 3 Another cross-sectional diagram along the C1C2 direction;

[0034] Figure 6 for Figure 3 A schematic diagram of a cross-section along the G1G2 direction;

[0035] Figure 7 This is a schematic diagram of a support layer provided in an embodiment of this application;

[0036] Figure 8 This is a schematic diagram of another support layer structure provided in an embodiment of this application;

[0037] Figure 9 An optical path diagram provided for an embodiment of this application;

[0038] Figure 10 Another optical path diagram provided for embodiments of this application;

[0039] Figure 11 Another optical path diagram provided in the embodiments of this application;

[0040] Figure 12 This application provides yet another optical path diagram.

[0041] Figure 13 This is a schematic diagram of the structure of a photovoltaic module provided in an embodiment of this application. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0043] In the description of the embodiments of this application, "multiple" means two or more, "multi-layer" means two or more layers, and "multi-piece" means two or more pieces, unless otherwise explicitly defined.

[0044] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order, or primary and secondary relationship of the indicated technical features.

[0045] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after it have an "or" relationship.

[0046] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0047] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application 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 the embodiments of this application. For example, if the device or element in the illustration is inverted, then the element described as "below," "under," "below," or "bottom" of other elements or features will be oriented "above" or "top" of said other elements or features. Therefore, the term "below" may cover both above and below orientation depending on the context in which the term is used, which will be obvious to those skilled in the art. Materials may be oriented in other ways (e.g., rotated 90 degrees, inverted, flipped), and the spatial relative descriptive terms used herein may be interpreted accordingly.

[0048] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0049] In the description of the embodiments of this application, when a component "includes" another component, other components are not excluded unless otherwise stated, and other components may be further included. The formation or provision of a second component above or on a first component, or on the surface of a first component, or on one side of a first component, may include embodiments where the first and second components are in direct contact, and may also include embodiments where an additional component may be present between the first and second components, thereby preventing direct contact between the first and second components. For simplicity and clarity, various components may be drawn at different scales. In the drawings, some layers / components may be omitted for simplicity. Unless otherwise specified, the formation or provision of a second component on the surface of a first component refers to direct contact between the first and second components. The term "component" may refer to: layer, film, region, portion, structure, etc.

[0050] Currently, in photovoltaic modules, the areas where solar cells are not arranged include the spacing between cells within a cell string, the spacing between strings, the location of busbars, and the creepage distances around the perimeter. Related technologies apply films to the cell and string spacing locations to improve light reflectivity at these locations; however, the creepage distances and busbars around the perimeter are not fully utilized. Busbars consist of a copper base and a tin-lead alloy layer hot-dip plated around the outer ring of the copper base. In-depth research shows that tin-lead alloys primarily reflect light diffusely, with only about 5%–15% of the reflected light being utilized, resulting in poor light utilization.

[0051] Based on this, the embodiments of this application provide a photovoltaic module, with reference to... Figures 1 to 3As shown, it includes: multiple battery string groups 1 arranged along a first preset direction OA; battery string groups 1 including multiple battery strings 10 arranged along a second preset direction OB; battery strings 10 including a first side F1 and a second side F2 arranged opposite to each other along the first preset direction OA; the first preset direction OA and the second preset direction OB intersect; a first bus unit 3 disposed between two adjacent battery string groups 1, the first bus unit 3 including multiple first bus bars 31 arranged at intervals; a second bus unit 2 disposed along the first preset direction OA, on the first side F1 of the first battery string group 1 and the second side F2 of the last battery string group 1; the second bus unit 2 including multiple second bus bars 21 arranged at intervals; and multiple reflective structures 4 disposed on the surface of the first bus bars 31 and / or the second bus bars 21.

[0052] In this embodiment, the first preset direction can be the length direction of the photovoltaic module, and the second preset direction can be the width direction of the photovoltaic module; alternatively, the first preset direction can be the width direction of the photovoltaic module, and the second preset direction can be the length direction of the photovoltaic module. The specific direction can be determined based on the number and size of the battery string. The first and second busbar units are used to collect the current from the battery string. The specific structure of the battery string can be obtained from relevant technologies and will not be described in detail here.

[0053] In this embodiment, multiple battery string groups can be connected in series or in parallel; within each battery string group, multiple battery strings can be connected in series or in parallel; Reference Figure 1 As shown, each battery string 10 may include multiple electrically connected battery cells 101. Figure 1The illustration uses a battery string 10 comprising six battery cells 101 as an example. The specific number of battery cells can be determined according to actual requirements. The specific type of battery cell is not limited. For example, the battery cell includes, but is not limited to, one or any combination of PERC (Passivated Emitter Rear Cell), BC (Back Contact), TOPCon (Tunnel Oxide Passivated Contact), HIT / HJT (Heterojunction Technology), thin-film solar cells, or tandem solar cells. Thin-film solar cells include, but are not limited to, perovskite thin-film solar cells, copper indium selenide (CIGS) thin-film solar cells, gallium arsenide (GaAs) thin-film solar cells, or cadmium sulfide (CdS) thin-film solar cells. Tandem solar cells include, but are not limited to, perovskite cells stacked with crystalline silicon cells, perovskite cells stacked with perovskite cells, or perovskite cells stacked with thin-film cells. In some embodiments, the battery cell can be a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell, or a multi-component compound solar cell. Specifically, a multi-component compound solar cell can be a cadmium sulfide solar cell, a gallium arsenide solar cell, a CIGS solar cell, or a perovskite solar cell. The size of the solar cell is not limited; for example, the solar cell can be a complete solar cell, half a solar cell, or a quarter of a solar cell.

[0054] In this embodiment, the first busbar can be electrically connected to one or more battery cells, and the second busbar can be electrically connected to one or more battery cells. The battery cells have multiple solder strips, and the first and second busbars are connected to these solder strips to achieve current collection.

[0055] In this embodiment of the application, the reflective structure is disposed on the surface of the first busbar and / or the second busbar, including: the reflective structure being disposed on the surface of the first busbar can improve the utilization rate of light rays incident on the first busbar; or, the reflective structure being disposed on the surface of the second busbar can improve the utilization rate of light rays incident on the second busbar; or, the reflective structure being disposed on both the surface of the first busbar and the surface of the second busbar can improve the utilization rate of light rays incident on both the first and second busbars.

[0056] In this embodiment, a reflective structure is provided on the surface of one side of the first busbar and / or the second busbar. When light shines on the reflective structure, some of the light is reflected by the reflective structure onto the adjacent battery string, thereby improving the utilization rate of the light shining on the first busbar and / or the second busbar, and further improving the component power.

[0057] In some embodiments, to reduce manufacturing difficulty and cost, the reflective structure can be separated from the first busbar and / or the second busbar. The reflective structure is not integrally formed with the first busbar and / or the second busbar. If the reflective structure is disposed on the surface of the first busbar, the reflective structure and the first busbar can be separated, and the reflective structure and the first busbar can be fixed by bonding or other methods. If the reflective structure is disposed on the surface of the second busbar, the reflective structure and the second busbar can be separated, and the reflective structure and the second busbar can be fixed by bonding or other methods. If the reflective structure is disposed on both the surface of the first and second busbars (i.e., reflective structures are disposed on the surfaces of both the first and second busbars), then the reflective structure disposed on the surface of the first busbar can be separated from the first busbar, and the two can be fixed by bonding or other methods; the reflective structure disposed on the surface of the second busbar can also be separated from the second busbar, and the two can be fixed by bonding or other methods.

[0058] In some embodiments, reference Figure 4 As shown, the reflective structure 4 includes an insulating layer 41, a support layer 42 and a reflective layer 43 stacked sequentially. The insulating layer 41 is in contact with and fixed to the first busbar 31 and / or the second busbar 21. The reflective layer 43 is used to partially reflect the light entering the reflective layer 43 to the adjacent battery string 10.

[0059] To further reflect more light incident on the reflective layer onto adjacent battery strings, the reflective layer can be made of a metallic material with a reflectivity greater than 85%, such as an aluminum or silver reflective layer. For ease of fabrication, the support layer can be made of a polymer material; that is, it can be a polymer support layer. The metallic reflective layer can be fabricated on the polymer support layer using electroforming, vapor deposition, or dip-coating processes.

[0060] In some embodiments, the insulating layer is an insulating adhesive layer, which is bonded and fixed to the first busbar and / or the second busbar, thereby improving the fixing effect, preventing the reflective structure from falling off, and improving product reliability.

[0061] If the reflective structure is located on the surface of the second busbar, in some embodiments, considering the film application accuracy and the offset caused during the lamination process, refer to... Figure 4 As shown, the width W1 of the reflective structure 4 disposed on the surface of the second busbar 21 is greater than or equal to the width W2 of the second busbar 21. For example, the width of the reflective structure disposed on the surface of the second busbar can be 3mm to 6mm. In order to further improve the component power, the width of the reflective structure disposed on the surface of the second busbar can be selected to be greater than the width of the second busbar.

[0062] In some embodiments, in order to reflect more light while avoiding exposure of the second busbar due to the offset of the reflective structure during lamination, refer to Figure 5 As shown, the reflective structure 4, which is disposed on the surface of the second busbar 21, extends towards the adjacent battery string from the side closest to it.

[0063] To avoid obstructing adjacent battery strings and to prevent short circuits caused by punctures in the insulating layer of the reflective structure, the reflective structure on the surface of the second busbar, near the adjacent battery string, cannot extend to the surface of the adjacent battery string. Therefore, a gap exists between the reflective structure on the surface of the second busbar and the adjacent battery string. (Reference) Figure 5 As shown, the reflective structure 4 disposed on the surface of the second busbar 21 is located on the side near the adjacent battery string, with a spacing d between it and the adjacent battery string of 0.2mm to 3mm. The spacing D between the second busbar 21 and the adjacent battery string is 2mm to 3mm, where d is less than D. Considering the operability of the process, d is 1mm to 2mm. At this time, the reflective structure 4 disposed on the surface of the second busbar 21 covers part of the gap between the second busbar 21 and the adjacent battery string, as well as part of the side of the second busbar 21 near the adjacent battery string.

[0064] To avoid affecting the creepage distance of the components, refer to Figure 5 As shown, the reflective structure 4 disposed on the surface of the second busbar 21 is away from the side of the adjacent battery string and does not extend beyond the edge of the second busbar 21. That is, the reflective structure 4 disposed on the surface of the second busbar 21 is away from the side of the adjacent battery string and is at a certain distance y from the edge of the second busbar 21.

[0065] If the reflective structure is disposed on the surface of the first busbar, in some embodiments, considering the film application accuracy and the offset caused during the lamination process, the width of the reflective structure disposed on the surface of the first busbar is greater than the width of the first busbar. For example, the width of the reflective structure disposed on the surface of the first busbar can be 4mm to 8mm. The center of the width of the reflective structure disposed on the surface of the first busbar coincides with the center of the width of the first busbar.

[0066] In some embodiments, in order to reflect more light while avoiding exposure of the first busbar due to the offset of the reflective structure during lamination, refer to Figure 6 As shown, the reflective structure 4, which is disposed on the surface of the first busbar 31, extends to the adjacent battery strings on both sides.

[0067] To avoid obstructing adjacent battery strings and to prevent short circuits caused by punctures in the insulating layer of the reflective structure, the reflective structure on the surface of the first busbar is positioned close to the side of the battery string and does not extend to the surface of the corresponding battery string; the reflective structure on the surface of the first busbar is positioned close to the side of the battery string and has a gap between it and adjacent battery strings. (Reference) Figure 6 As shown, the reflective structure 4 disposed on the surface of the first busbar 31, near the battery string, has a spacing of d1 between it and the adjacent battery string, where d1 is 0.2mm to 3mm. The spacing between the first busbar 31 and the adjacent battery string is D1, where D1 is 2mm to 3mm. Since d1 is less than D1, considering process operability, d1 is 1mm to 2mm. In this case, the reflective structure 4 disposed on the surface of the first busbar 31 covers part of the gap between the first busbar 31 and the adjacent battery strings on both sides, as well as part of the side of the first busbar 31 near the adjacent battery strings on both sides.

[0068] In some embodiments, to further improve the reflection effect of the reflective structure, reference is made. Figure 7 and Figure 8 As shown, the support layer includes at least one protrusion 420 arranged along a first preset direction OA. The longitudinal section of the protrusion 420 is triangular. The triangle includes a base a, a first side c, and a second side b connected to the base a. A reflective layer is disposed on the surface of the protrusion facing away from the insulating layer.

[0069] In the reflective structure disposed on the surface of the second busbar, the first side is close to the adjacent battery string, and the second side is away from the adjacent battery string, as shown in the reference. Figure 7 As shown, the angle β between the first side c and the second side b is 90 degrees to 120 degrees, the angle α between the first side c and the bottom side a is 22 degrees to 32.5 degrees, and the length L1 of the first side c is greater than or equal to the length L2 of the second side b. Considering that the distance between the second busbar and the adjacent solar cell is 2 mm, and the height h of the protrusion is 10 μm to 30 μm, this allows more light to be reflected onto the solar cell.

[0070] In the reflective structure set on the surface of the first busbar, reference Figure 8 As shown, the angle between the first side c and the second side b is 90 degrees to 120 degrees, and the length L1 of the first side c and the length L2 of the second side b are the same. Considering that the distance between the first busbar and the adjacent solar cell is 2 mm, and the height h of the protrusion is 10 μm to 30 μm, this allows more light to be reflected onto the solar cell.

[0071] It should be noted that since battery cells are provided on both sides of the first busbar, the reflective structure on the surface of the first busbar can reflect light from both sides of the protrusion. Therefore, the shape of the longitudinal section of the protrusion can be an isosceles triangle.

[0072] The following explains the principle behind the protrusion in the reflective structure located on the surface of the second busbar.

[0073] refer to Figure 9 As shown, along the first preset direction OA, a battery cell 101 is disposed on one side of the second busbar 21, and no battery cell is disposed on the other side, which is the edge of the assembly. When external light a1 is incident perpendicularly through the cover plate 5 onto the reflective layer 43 on the surface s1 of the protrusion of the reflective structure 4 near the battery cell, the reflective layer 43 on the surface s1 of the protrusion of the reflective structure 4 near the battery cell can reflect this part of the light to the adjacent battery cell 101. However, when external light b1 is incident perpendicularly through the cover plate 5 onto the reflective layer 43 on the surface s2 of the protrusion of the reflective structure 4 away from the battery cell, the reflective layer 43 on the surface s2 of the protrusion of the reflective structure 4 away from the battery cell will reflect this part of the light to the side of the second busbar 21 away from the battery cell 101, that is, this part of the light is not effectively utilized. To improve the utilization rate of light in this part, the longitudinal section of the protrusion is triangular in shape. The triangle includes a base and a first side and a second side connected to the base. The first side is close to the adjacent battery string, and the second side is away from the adjacent battery string. The included angle β between the first side and the second side is 90 degrees to 120 degrees, and the included angle α between the first side and the base is 22 degrees to 32.5 degrees. The length L1 of the first side is greater than or equal to the length L2 of the second side.

[0074] Here, we take an example where the angle β between the first and second sides is 115 degrees.

[0075] refer to Figure 10 As shown, the longitudinal section of the protrusion 420 is an isosceles triangle, with an angle α of 32.5 degrees between the first side and the base a. The first side includes a first segment c1 and a second segment c2. Light rays hitting the first segment c1 of the left protrusion 420 are reflected and not blocked by the right protrusion 420; light rays hitting the second segment c2 of the left protrusion are reflected and blocked by the right protrusion 420, preventing them from entering the adjacent solar cell. The first segment c1 accounts for 80% of the length of the first side. The higher this proportion, the lower the proportion of obstruction and the higher the light utilization rate.

[0076] refer to Figure 11 As shown, the longitudinal section of the protrusion 420 is a non-isosceles triangle, with the length of the first side L1 greater than the length of the second side L2. When the angle α between the first side and the base a is less than 32.5 degrees, the first segment c1 accounts for 90% of the length of the first side. That is, by increasing the length of the first side while decreasing the angle α between the first side and the base, the proportion of the first segment's length to the first side in the protrusion can be increased. Additionally, refer to... Figure 12As shown, an encapsulating film is also provided between the cover plate 5 and the battery string. Light reflected by the reflective layer on the protrusion 420 will be transmitted to the cover plate 5 via the encapsulating film. Some of the light will then be reflected by the cover plate 5 to the battery cells, and some will be refracted by the cover plate 5 to the outside. The refractive index of the cover plate to air is 1.51. Based on the law of refraction, the critical angle for total internal reflection is calculated. The calculation shows that when the angle α between the first side and the bottom side is greater than 22 degrees, the light reflected by the reflective layer on the protrusion 420 will undergo total internal reflection on the cover plate, meaning it will all be reflected to the battery cells and will not be refracted to the outside.

[0077] In some embodiments, reference Figure 13 As shown, the photovoltaic module may also include an encapsulating film 6 and a cover plate 5. The encapsulating film 6 is used to cover the battery string group 1, the first busbar 31 and the second busbar 21, and the cover plate 5 is used to cover the side of the encapsulating film 6 away from the battery string group 1, the first busbar 31 and the second busbar 21.

[0078] In some embodiments, the encapsulating film includes a first encapsulating layer and a second encapsulating layer. The first encapsulating layer covers one of the front or back sides of the battery string, and the second encapsulating layer covers the other of the front or back sides of the battery string. Specifically, at least one of the first or second encapsulating layer can be an organic encapsulating film such as polyvinyl butyral (PVB) film, ethylene-vinyl acetate copolymer (EVA) film, polyvinyl octene elastomer (POE) film, or polyethylene terephthalate (PET) film. Alternatively, at least one of the first or second encapsulating layer can also be an EP film, an EPE film, or a PVP film. Here, EP film refers to a co-extruded film composed of stacked EVA film and POE film; EPE film refers to a co-extruded film formed by sequentially stacking EVA film, POE film, and EVA film; and PVP film refers to a co-extruded film formed by stacking POE film, EVA film, and POE film. Co-extruded films can be prepared by sequentially extruding one or more raw materials onto another pre-made film during the film processing, or by bonding different types of pre-made films together.

[0079] In some cases, there is a boundary between the first encapsulation layer and the second encapsulation layer before lamination. After lamination, the photovoltaic module no longer has the concept of a first encapsulation layer and a second encapsulation layer, that is, the first encapsulation layer and the second encapsulation layer have formed an integral encapsulation film.

[0080] In some embodiments, the cover plate can be a glass cover plate, a plastic cover plate, or other cover plate with light-transmitting function. Specifically, the surface of the cover plate facing the encapsulating film can be an uneven surface or a textured surface containing multiple raised structures, thereby increasing the utilization rate of incident light. The cover plate includes a first cover plate and a second cover plate, the first cover plate being opposite to the first encapsulation layer, and the second cover plate being opposite to the second encapsulation layer.

[0081] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of this application. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this application.

Claims

1. A photovoltaic module, characterized in that, include: Multiple battery string groups are arranged along a first preset direction; the battery string group includes multiple battery strings arranged along a second preset direction; each battery string includes a first side and a second side arranged opposite to each other along the first preset direction; the first preset direction and the second preset direction intersect. A first busbar unit is disposed between two adjacent battery string groups, and the first busbar unit includes a plurality of first busbars disposed at intervals; The second busbar unit is disposed on the first side of the battery string group located at the first position and the second side of the battery string group located at the last position, arranged along the first preset direction; the second busbar unit includes a plurality of second busbars arranged at intervals; Multiple reflective structures are disposed on the surface of the first busbar and / or the second busbar.

2. The photovoltaic module according to claim 1, characterized in that, The reflective structure can be detached from the first busbar and / or the second busbar.

3. The photovoltaic module according to claim 2, characterized in that, The reflective structure includes an insulating layer, a support layer, and a reflective layer stacked sequentially. The insulating layer is fixed in contact with the first busbar and / or the second busbar. The reflective layer is used to partially reflect light entering the reflective layer to the adjacent battery string.

4. The photovoltaic module according to claim 3, characterized in that, The insulating layer is an insulating adhesive layer, which is bonded and fixed to the first busbar and / or the second busbar.

5. The photovoltaic module according to claim 1, characterized in that, The width of the reflective structure disposed on the surface of the second busbar is greater than or equal to the width of the second busbar.

6. The photovoltaic module according to claim 1, characterized in that, The reflective structure disposed on the surface of the second busbar extends toward the adjacent battery string from the side close to it.

7. The photovoltaic module according to claim 6, characterized in that, The reflective structure disposed on the surface of the second busbar covers a portion of the gap between the second busbar and the adjacent battery string, as well as a portion of the side of the second busbar near the adjacent battery string.

8. The photovoltaic module according to claim 7, characterized in that, The distance between the second busbar and the adjacent battery string is 2mm~3mm; the distance between the reflective structure disposed on the surface of the second busbar and the side close to the adjacent battery string is 0.2mm~3mm.

9. The photovoltaic module according to claim 6, characterized in that, The reflective structure disposed on the surface of the second busbar is located away from the side of the adjacent battery string and does not extend beyond the edge of the second busbar.

10. The photovoltaic module according to claim 1, characterized in that, The width of the reflective structure disposed on the surface of the first busbar is greater than the width of the first busbar.

11. The photovoltaic module according to claim 1, characterized in that, The reflective structure disposed on the surface of the first busbar extends to the adjacent battery strings on both sides.

12. The photovoltaic module according to claim 11, characterized in that, The reflective structure disposed on the surface of the first busbar covers a portion of the gap between the first busbar and the battery strings on both adjacent sides, as well as a portion of the side of the first busbar near the battery strings on both adjacent sides.

13. The photovoltaic module according to claim 12, characterized in that, The distance between the first busbar and the adjacent battery string is 2mm to 3mm; the distance between the reflective structure disposed on the surface of the first busbar and the side close to the adjacent battery string is 0.2mm to 3mm.

14. The photovoltaic module according to claim 3, characterized in that, The support layer includes at least one protrusion arranged along the first preset direction, and the longitudinal section of the protrusion is triangular in shape; the triangle includes a base, and a first side and a second side respectively connected to the base.

15. The photovoltaic module according to claim 14, characterized in that, The angle between the first side and the second side is 90 degrees to 120 degrees.

16. The photovoltaic module according to claim 15, characterized in that, In the reflective structure disposed on the surface of the second busbar, the first side is close to the adjacent battery string, the second side is away from the adjacent battery string, and the angle between the first side and the bottom side is 22 degrees to 32.5 degrees.

17. The photovoltaic module according to claim 15, characterized in that, In the reflective structure disposed on the surface of the second busbar, the first side is close to the adjacent battery string, the second side is away from the adjacent battery string, and the length of the first side is greater than or equal to the length of the second side.

18. The photovoltaic module according to claim 15, characterized in that, In the reflective structure disposed on the surface of the first busbar, the length of the first side and the length of the second side are the same.

19. The photovoltaic module according to claim 14, characterized in that, The height of the protrusion is 10um to 30um.

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