Photovoltaic assembly

Abstract

A photovoltaic assembly, comprising: a back panel (100) and a front panel (200), which are arranged opposite each other; battery strings (300), which are arranged between the back panel (100) and the front panel (200); bus-bars (400), which are electrically connected to the battery strings (300); and waterproof structures (600), which are sandwiched between the back panel (100) and the front panel (200), wherein a lead hole (K) is provided in the back panel (100), each bus-bar (400) is provided with a lead-out end (401), and the lead-out end (401) is threaded through the lead hole (K) by means of a waterproof structure (600); and the orthographic projection of the lead hole (K) on a reference plane is located within an outer contour of the orthographic projections of the waterproof structures (600) on the reference plane, the reference plane being a plane parallel to the plane where the lead hole (K) is located.

Description

Photovoltaic panels

[0001] Related applications

[0002] This application claims priority to Chinese patent application number 202310755421.4, filed on June 26, 2023, entitled “Photovoltaic Module,” the entire text of which is hereby incorporated by reference. Technical Field

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

[0004] In related art, the back panel of a photovoltaic module is equipped with lead holes for the busbars that connect the battery strings. The busbars pass through the lead holes and then connect to the junction box. However, moisture can easily enter the photovoltaic module through the lead holes, causing moisture corrosion to the battery strings, thereby affecting the output power of the photovoltaic module and even posing a safety hazard.

[0005] Summary of the Invention

[0006] According to various embodiments of the present application, a photovoltaic module is provided.

[0007] An embodiment of the present application provides a photovoltaic assembly, including:

[0008] A back panel and a front panel arranged opposite to each other;

[0009] Battery string, located between the back plate and the front plate;

[0010] a bus bar electrically connected to the battery string; and

[0011] The waterproof structure is sandwiched between the back plate and the front plate; the back plate is provided with a lead hole, and the bus bar has a lead end, which passes through the waterproof structure and out of the lead hole;

[0012] The orthographic projection of the lead hole on the reference surface is located within the outer contour of the orthographic projection of the waterproof structure on the reference surface, and the reference surface is a plane parallel to the plane where the lead hole is located.

[0013] In one embodiment, the inner contour of the orthographic projection of the waterproof structure on the reference surface is outside the orthographic projection of the lead hole on the reference surface; or

[0014] The inner contour of the orthographic projection of the waterproof structure on the reference surface coincides with the outer contour of the orthographic projection of the lead-in hole on the reference surface; or

[0015] At least a portion of an inner contour of an orthographic projection of the waterproof structure on the reference surface is located within the orthographic projection of the lead hole on the reference surface.

[0016] In one embodiment, the inner contour of the orthographic projection of the waterproof structure on the reference surface is a regular shape; or

[0017] The inner contour of the orthographic projection of the waterproof structure on the reference surface is an irregular shape.

[0018] In one embodiment, the busbar has a bent portion located upstream of the lead-out end along the lead-out direction;

[0019] Wherein, along the lead-out direction, the bent portion is located between the waterproof structure and the lead-in hole; or

[0020] The bent portion is located within the waterproof structure.

[0021] In one embodiment, the orthographic projection of the lead hole on the reference surface is located on the orthographic projection of the waterproof structure on the reference surface.

[0022] In one embodiment, the waterproof structure has an exposed surface exposed to the lead-in hole;

[0023] The lead-out terminal is passed through the exposed surface.

[0024] In one embodiment, the outer contour of the orthographic projection of the waterproof structure on the reference surface is a regular shape; or

[0025] The outer contour of the orthographic projection of the waterproof structure on the reference surface is an irregular shape.

[0026] In one embodiment, the waterproof structure is made of rubber, rubber mixture, silicone, silicone mixture, silicone rubber, resin or mixed materials, and the mixed materials include at least one of rubber, rubber mixture, silicone, silicone mixture, silicone rubber and resin.

[0027] In one embodiment, the back plate is a glass plate, a metal composite plate, a composite polymer plate containing a metal film layer, or a composite polymer plate containing an inorganic non-metallic film layer.

[0028] In one embodiment, the photovoltaic module further includes an encapsulation film;

[0029] The battery string is encapsulated in an encapsulation film, and the encapsulation film is bonded between the back plate and the front plate.

[0030] The details of one or more embodiments of the present application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the disclosed drawings without any creative work.

[0032] FIG1 is a schematic structural diagram of a photovoltaic module in an embodiment of the related art.

[0033] FIG2 is a schematic diagram of a partially enlarged cross-sectional structure of the photovoltaic module shown in FIG1 along the AA direction.

[0034] FIG3 is a schematic top view of the partially enlarged cross-sectional structure shown in FIG2 .

[0035] FIG4 is a schematic cross-sectional view of a photovoltaic module according to another embodiment of the related art.

[0036] FIG5 is a schematic diagram of the structure of a photovoltaic module in some embodiments of the present application.

[0037] FIG6 is a schematic diagram of a partially enlarged structure of the photovoltaic module shown in FIG5 .

[0038] FIG7 is a schematic diagram of a partially enlarged cross-sectional structure taken along line BB in one embodiment of the photovoltaic module shown in FIG5 .

[0039] FIG8 is a schematic top view of the partially enlarged cross-sectional structure shown in FIG7 .

[0040] FIG9 is a schematic diagram of a partially enlarged cross-sectional structure taken along line BB in another embodiment of the photovoltaic assembly shown in FIG5 .

[0041] FIG10 is a schematic top view of the partially enlarged cross-sectional structure shown in FIG9 .

[0042] FIG11 is a schematic diagram of a partially enlarged cross-sectional structure taken along line BB in another embodiment of the photovoltaic assembly shown in FIG5 .

[0043] FIG12 is a schematic top view of the partially enlarged cross-sectional structure shown in FIG11 .

[0044] FIG13 is a schematic diagram of a partially enlarged cross-sectional structure taken along line BB in another embodiment of the photovoltaic module shown in FIG5 .

[0045] FIG14 is a schematic top view of the partially enlarged cross-sectional structure shown in FIG13 .

[0046] FIG15 is a schematic diagram of a partially enlarged structure of the photovoltaic assembly shown in FIG5 in one embodiment.

[0047] FIG16 is a schematic diagram of a partially enlarged structure of the photovoltaic assembly shown in FIG5 in another embodiment.

[0048] FIG17 is a schematic diagram of a partially enlarged structure of the photovoltaic assembly shown in FIG5 in yet another embodiment.

[0049] FIG18 is a schematic diagram of a partially enlarged structure of the photovoltaic assembly shown in FIG5 in yet another embodiment.

[0050] Explanation of the accompanying drawings: Back panel 10, lead hole k; Front panel 20; Battery string 30; Bus bar 40, Lead end 41; Encapsulation film 50; Waterproof structure 60; Back panel 100, Lead hole K; Front panel 200; Battery string 300; Bus bar 400, Lead end 401, Bend portion 402; Encapsulation film 500, First film layer 510, Second film layer 520; Waterproof structure 600, Exposed surface m, Dimension d; Interconnection bar L; First direction F1, Second direction F2. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0052] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0053] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0054] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. It is worth noting that in the following description and the attached claims, "electrical connection" between one feature and another feature not only includes one feature being in direct contact with another feature to form an electric energy transmission or current transmission channel, but also includes an intermediate feature between one feature and another feature, and the one feature, the other feature and the intermediate feature between them form an electric energy transmission channel or a current transmission channel to achieve electric energy transmission or transmission. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0055] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0056] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0057] With the development of the photovoltaic module industry, various high-efficiency cells have emerged, such as HJT (Hereto-junction with Intrinsic Thin-layer) cells, TopCon (Tunnel Oxide Passivating Contacts) cells, perovskite cells, and tandem cells. While high-efficiency cells offer higher photoelectric conversion efficiencies, their electrical and optical structures are more sensitive to environmental factors. To prevent moisture from penetrating into the interior of photovoltaic modules, higher requirements are placed on the water-resistant properties of the module's packaging structure.

[0058] Figure 1 shows a schematic structural diagram of a photovoltaic module in an embodiment of the related technology; Figure 2 shows a schematic diagram of a partially enlarged sectional structure in the AA direction of the photovoltaic module shown in Figure 1; Figure 3 shows a schematic top view of the partially enlarged sectional structure shown in Figure 2; for ease of explanation, only the content related to the embodiment of the related technology is shown.

[0059] Referring to Figures 1 to 3, an embodiment of the related art provides a photovoltaic module, which includes a backsheet 10, a frontsheet 20, a cell string 30, a busbar 40, and an encapsulating film 50. The backsheet 10 and the frontsheet 20 are arranged relative to each other, and the cell string 30 is disposed between the backsheet 10 and the frontsheet 20. For example, the cell string 30 is encapsulated within the encapsulating film 50, which is bonded between the backsheet 10 and the frontsheet 20. As shown in Figures 2 and 3, a lead hole k is provided on the backsheet 10. The busbar 40 is electrically connected to the cell string 30, and the lead end 41 of the busbar 40 extends through the lead hole k and is connected to a junction box (not shown). As shown in Figure 2, if moisture is present outside the lead hole k, the moisture will enter the interior of the photovoltaic module through the lead hole k, causing moisture erosion on the cell string 30, thereby affecting the output power of the photovoltaic module and even posing a safety hazard.

[0060] With reference to Figure 2 , since the lead hole k is formed along the first direction F1, moisture will generally enter the interior of the photovoltaic module through the lead hole k along the first direction F1. As shown in Figure 4 , which shows a cross-sectional view of a photovoltaic module according to another embodiment of the related art, since the photovoltaic module is relatively thin along the first direction F1, the inventors of the present application have attempted to install a waterproof structure 60 on the outside of the photovoltaic module. The waterproof structure 60 is arranged to cover the lead hole k along the first direction F1. This prevents moisture from entering the interior of the photovoltaic module along the first direction F1, thereby improving the waterproofing capability of the lead hole k.

[0061] However, the inventors of this application have discovered that if the waterproof structure 60 is positioned outside the photovoltaic module—that is, outside the backsheet 10 near the lead hole k—when the photovoltaic module is subjected to external stress, the waterproof structure 60 positioned outside the photovoltaic module may become detached, displaced, or even fall off the backsheet 10, causing failure of the waterproof structure 60. For example, after the photovoltaic module is laminated, the photovoltaic module is exposed to temperatures exceeding 140°C, and the adhesion on the outer surface of the backsheet 10 is very low. During subsequent manufacturing processes, the vibration of the assembly line and the external stress caused by subsequent cleaning, handling, and flipping can cause the waterproof structure 60 to fail as described above. For another example, since the lead ends 41 of the busbar 40 extend through the lead hole k, they are free ends and are subject to external stress. This stress can then be transferred to the waterproof structure 60, causing delamination between the busbar 40 and the waterproof structure 60, creating a channel for water vapor to penetrate, further weakening the waterproofing effect. If, in order to improve the stability of the waterproof structure 60 provided on the outside of the photovoltaic module, a fixing structure is added, the structure of the photovoltaic module exterior becomes more complicated, which will also affect the subsequent installation process of the photovoltaic module. In addition, even if a fixing structure is provided, the fixing structure still faces the risk of external stress, and the reliability and layout of the fixing structure need to be further considered, which makes it difficult to achieve the desired waterproof effect.

[0062] After in-depth research, the inventors of this application discovered that photovoltaic modules are typically pressed together tightly by equipment such as solar photovoltaic laminators, applying a certain amount of pressure. This creates a certain amount of interlayer pressure between the modules. To address the aforementioned issues of waterproofing failure caused by external stress and the complex nature of related waterproofing structures, the inventors of this application attempted to increase the reliability of the waterproofing structure by placing it within the modules. This could mitigate the risk of water vapor entering the modules through the lead holes, reduce its impact on the modules' output power, and improve safety.

[0063] Figure 5 shows a schematic structural diagram of a photovoltaic module in some embodiments of the present application; Figure 6 shows a partially enlarged structural schematic diagram of the photovoltaic module shown in Figure 5; Figure 7 shows a partially enlarged cross-sectional structural schematic diagram of the lower BB direction of an embodiment of the photovoltaic module shown in Figure 5; Figure 8 shows a top view schematic diagram of the partially enlarged cross-sectional structure shown in Figure 7; for ease of explanation, only the content related to the embodiments of the present application is shown.

[0064] In some embodiments, referring to FIG. 5 to FIG. 7 , the photovoltaic module provided in the embodiments of the present application includes a backsheet 100 , a frontsheet 200 , a cell string 300 , a busbar 400 , a packaging film 500 and a waterproof structure 600 .

[0065] The backsheet 100 and the frontsheet 200 are arranged relative to each other. That is, in the first direction F1 shown in Figure 7, the backsheet 100 and the frontsheet 200 are arranged relative to each other. The first direction F1 is the thickness direction of the photovoltaic module. The frontsheet 200 refers to the panel facing the sunlight when the photovoltaic module is operating normally. Correspondingly, the backsheet 100 refers to the panel facing away from the sunlight when the photovoltaic module is operating normally. The frontsheet 200 can be a glass panel, and the backsheet 100 can be a glass panel, a metal composite panel, a composite polymer panel containing a metal film layer, a composite polymer panel containing an inorganic non-metallic film layer, or a polymer panel, etc. Among them, the glass panel is a plate-shaped component made of glass. The metal composite panel is a plate-shaped component made of a metal composite material formed of different metals. For example, the metal composite panel can be an aluminum-containing composite panel. The composite polymer panel containing a metal film layer is a plate-shaped component containing a metal film layer. The composite polymer panel containing an inorganic non-metallic film layer is a plate-shaped component containing an inorganic non-metallic film layer. The polymer sheet can be a polyethylene terephthalate sheet (PET sheet), a composite sheet of polyethylene terephthalate, a fluorine-containing material sheet, or a composite sheet of fluorine-containing materials. If the backsheet includes a metal film layer or an inorganic non-metallic film layer, the innermost and outermost layers of the backsheet can be polymer film layers, and the middle layer can be a metal film layer or an inorganic non-metallic film layer. The polymer film layer can provide insulation, while the metal film layer or the inorganic non-metallic film layer can further enhance the water vapor barrier capability.

[0066] It is understood that when the backsheet 100 is a glass sheet, a metal composite sheet, a composite polymer sheet containing a metal film layer, or a composite polymer sheet containing an inorganic non-metallic film layer, the backsheet 100 has even better water vapor barrier properties. For example, the frontsheet 200 and backsheet 100 can be glass sheets, and the photovoltaic module can be a double-glass module, which can further improve the water vapor barrier properties of the backsheet 100.

[0067] As shown in FIG7 and FIG8 , a lead hole K is provided on the back plate 100 , and the lead hole K is used to provide a channel for related circuits to extend out of the photovoltaic module.

[0068] The battery string 300 is disposed between the backplane 100 and the frontplane 200. The battery string 300 includes multiple battery cells. For example, the battery cells in the battery string 300 can be connected by electrically connecting the front electrode of one battery cell to the back electrode of an adjacent battery cell via an interconnection bar L. The interconnection bar L enables connection between battery cells in the same battery string 300. The specific connection structure of the battery string 300 can be configured based on actual usage, and this embodiment of the present application does not impose any specific limitations on this.

[0069] The busbar 400 is electrically connected to the cell strings 300. For example, the connection between adjacent cell strings 300 is achieved by connecting the busbar 400 to the tail ends of the interconnection bars L provided on the cell cells at the beginning and end of the cell strings 300. Taking Figures 5 and 6 as examples, busbars 400 are provided at both the ends and the middle of the photovoltaic module. In this embodiment of the present application, the busbar 400 located in the middle of the photovoltaic module has a lead-out terminal 401.

[0070] The encapsulation film 500 is a component used to encapsulate the battery string 300. The encapsulation film 500 can provide mechanical buffering protection for the battery string 300 and is used to provide support between the waterproof structure 600 and the backplane 100 and front panel 200. The encapsulation film 500 can be an ethylene vinyl acetate copolymer film (EVA film), a polyvinyl butyral film (PVB film), a thermoplastic polyurethane film (TPU film), a polydimethylsiloxane film (PDMS film), a polyolefin elastomer film (POE film), an ionomer ethylene copolymer film, etc. The encapsulation film 500 can include a first film layer 510 and a second film layer 520. The battery string 300 is encapsulated between the first film layer 510 and the second film layer 520. The first film layer 510 is bonded to the backplane 100, and the second film layer 520 is bonded to the front panel 200. The material of the encapsulation film 500 can be selected according to actual usage, and this embodiment of the application does not impose specific limitations on this.

[0071] The waterproof structure 600 is a component with a certain water-blocking ability. The waterproof structure 600 is sandwiched between the back plate 100 and the front plate 200. That is, by relatively arranging the front plate 200 and the back plate 100, the waterproof structure 600 can be sandwiched between the back plate 100 and the front plate 200. The lead end 401 of the bus bar 400 passes through the lead hole K via the waterproof structure 600. That is, the lead end 401 of the bus bar 400 will first pass through the waterproof structure 600 before passing through the lead hole K. It can be understood that the lead hole K corresponds to the lead end 401 of the bus bar 400. For example, as shown in Figure 6, in the embodiment of the present application, it is illustrated that the bus bar 400 located in the middle of the photovoltaic module has a lead end 401. Accordingly, the lead hole K can be provided in the middle of the photovoltaic module.

[0072] The orthographic projection of the lead hole K on the reference surface lies within the outer contour of the orthographic projection of the waterproof structure 600 on the reference surface. The reference surface is a plane parallel to the plane where the lead hole K lies. In other words, the lead hole K can be roughly considered to be surrounded by the waterproof structure 600. As long as the orthographic projection of the lead hole K on the reference surface lies within the outer contour of the orthographic projection of the waterproof structure 600 on the reference surface, this embodiment of the application does not impose any specific restrictions on the structure of the waterproof structure 600 or the lead hole K.

[0073] Therefore, when the waterproof structure 600 is provided inside the photovoltaic module, after the photovoltaic module is laminated, the bonding force between the waterproof structure 600 and the back plate 100 and the front plate 200 is further tightened due to the adhesive force of the encapsulating film 500, which can improve the aforementioned situation of waterproof failure caused by interface detachment. At the same time, compared with the method of setting up an additional fixing structure, the overall structure is also simpler. In addition, after the photovoltaic module is laminated, the bus bar 400 located inside can be further fixed with the help of the waterproof structure 600, thereby improving the aforementioned situation of delamination between the lead end 401 of the bus bar 400 and the waterproof structure 600. When the lead hole K mentioned above is surrounded by the waterproof structure 600, when water vapor enters the interior of the photovoltaic module through the lead hole K, it will be blocked by the waterproof structure 600, thereby improving the situation of water vapor entering the interior of the photovoltaic module through the lead hole K.

[0074] The effectiveness of the waterproof structure 600 will be described below in conjunction with the above structure illustrated in the embodiment of the present application and related comparative examples.

[0075] Taking the photovoltaic module illustrated in FIG7 as an example, the waterproof structure 600 in FIG7 is set to fill the lead hole K to form the waterproof structure 600 shown in FIG12 and FIG13 as shown later, and the structure illustrated in FIG13 is used as an example of the present application (recorded as Group 1), the photovoltaic module illustrated in FIG2 is used as the first comparative example (recorded as Group 2), and the photovoltaic module illustrated in FIG13 does not include the bus bar 400 as the second comparative example (recorded as Group 3). In Groups 1 and 3, the first film layer 510 and the second film layer 520 are both made of EVA film. In Group 2, the encapsulating film 50 also includes two layers of film (i.e., a front film and a back film, not shown in the figure), and the encapsulating film 50 is made of POE film. In Groups 1 and 3, with reference to FIG7, the dimension d of the waterproof structure in the second direction F2 perpendicular to the first direction F1 is set to about 6 mm. Cobalt oxide test paper is set in the lead hole areas corresponding to Groups 1 to 3 and the edges of the battery strings, and the waterproof effectiveness is compared by the color of the cobalt oxide test paper.

[0076] The photovoltaic modules in Groups 1, 2, and 3 were boiled in water at 100°C for 96 hours. In Groups 1 and 3, the cobalt oxide test paper in the lead hole K area showed no discoloration, and even the cobalt oxide test paper at the edge of the cell string did not change color. In Group 2, moisture infiltrating through lead hole K caused the cobalt oxide test paper to change color, extending to approximately 15 mm from the cell edge.

[0077] It should be noted that, it is known that at an ambient temperature of 38°C, the water permeability of the EVA membrane is approximately 30 g / (m2 ·24h), the water permeability of POE membrane is about 4g / (m 2 ·24h). That is, the waterproof performance of EVA film is weaker than that of POE film.

[0078] In the above experimental results, even though the waterproof performance of the encapsulating film 500 in Groups 1 and 3 was weaker than that of Group 2, the waterproof structures 600 in Groups 1 and 3 were still able to effectively block water vapor penetration. Furthermore, the difference between Groups 1 and 3 lies in the presence or absence of the busbar 400. That is, Group 1 presents the structure provided by an embodiment of the present application, with the busbar 400 passing through the waterproof structure 600 and reaching the outside of the lead-out hole K. Group 3, based on the structure of Group 1, does not have the busbar 400 passing through the waterproof structure 600 and reaching the outside of the lead-out hole K. However, the waterproof structures 600 in Groups 1 and 3 are located in the same position. This further demonstrates that the path for water vapor to penetrate the battery string 300 through the lead-out hole K is primarily through the backsheet 100 and the contact surface between the waterproof structure 600 and the backsheet 100, and that the path through which the busbar 400 passes through the waterproof structure 600 is not the primary path for water vapor penetration. In other words, by providing the waterproof structure 600 within the photovoltaic module and allowing the busbar 400 to pass through it, the embodiment of the present application does not increase the water vapor penetration path, and thus does not weaken the waterproof effect. Of course, to further improve the waterproof effect, the water vapor penetration distance along the interface between the busbar 400 surface and the waterproof structure 600 can be increased by increasing the surface roughness of the busbar 400 or adding some microstructures.

[0079] Based on the above experimental results, the inventors of the present application further discovered that placing the waterproof structure 600 inside the photovoltaic module can increase the water vapor penetration distance compared to placing the waterproof structure 600 outside the photovoltaic module, thereby making the water-blocking ability of the waterproof structure 600 in the embodiment of the present application more superior.

[0080] In conjunction with the aforementioned discussion, if the waterproof structure 600 is located outside the photovoltaic module and provides waterproofing for the photovoltaic module in the first direction F1, it would be difficult to increase the dimension of the waterproof structure 600 in the first direction F1 due to the limited space and the thickness of the backsheet 100. For example, if the thickness of the backsheet 100 is 1.6 mm or 2 mm, if the waterproof structure 600 is located near the lead hole K, the maximum dimension of the waterproof structure 600 is the thickness of the backsheet 100 (1.6 mm or 2 mm). However, in the embodiment of the present application, using Figure 7 as an example, the waterproof structure 600 not only blocks water in the first direction F1 but also in the second direction F2. Compared to the method of placing the waterproof structure 600 outside the photovoltaic module, this provides an additional water-blocking path. Because the internal space of the photovoltaic module near the lead hole K can be utilized, the dimension d of the waterproof structure 600 in the second direction F2 can be increased (for example, dimension d can be greater than 6 mm, which is greater than the thickness of the backsheet 100 mentioned above).

[0081] Although not wishing to be bound by theory, the inventors of this application have continued to conduct in-depth research and found that there is the following relationship between the water vapor flow time t0 of the waterproof structure 600 set at the lead hole K and the water vapor flow time t1 of the waterproof structure 600 set inside the photovoltaic module: t1 = (d1 / d0)2t = 9t0. Where d0 is the thickness of the back sheet 100, and d1 is the dimension d of the waterproof structure 600. In other words, the water vapor flow time t0 of the waterproof structure 600 set at the lead hole K is less than the water vapor flow time t1 of the waterproof structure 600 set inside the photovoltaic module. When the thickness of the back sheet 100 is 2 mm and the dimension d is 6 mm, t1 = (6 / 2) 2 t0=9t0. Therefore, the arrangement of the waterproof structure 600 provided in the embodiment of the present application can prolong the water vapor flow time, making the water vapor penetration distance longer, and obviously having a more excellent water blocking ability.

[0082] Therefore, the waterproof structure 600 disposed inside the photovoltaic module not only reduces the risk of failure due to external stress caused by its placement outside the photovoltaic module, but also utilizes the laminate pressure of the photovoltaic module to rigidly constrain the waterproof structure 600, thereby further strengthening the connection between the waterproof structure 600 and the backsheet 100 and frontsheet 200. Furthermore, compared to the arrangement where the waterproof structure 600 is disposed outside the photovoltaic module, an additional and longer water-blocking path is created.

[0083] Therefore, the arrangement of the waterproof structure 600 in the embodiment of the present application not only improves the waterproof ability at the lead hole K, but also improves the reliability of the waterproof structure 600, thereby reducing the impact on the output power of the photovoltaic module and improving safety performance.

[0084] In some embodiments, the orthographic projection of waterproof structure 600 onto the reference surface has an inner contour. That is, waterproof structure 600 can be considered a hollow structure with an inner diameter. Waterproof structure 600 can be a regular structure, such as a body of revolution. It can also be an irregular structure, such as a radiating structure. The choice of waterproof structure can be based on the internal structural layout of the photovoltaic module and is not specifically limited in this embodiment of the present application.

[0085] Specifically, in some embodiments, the inner contour of the orthographic projection of the waterproof structure 600 on the reference surface is located outside the orthographic projection of the lead hole K on the reference surface. That is, as shown in Figures 7 and 8 , when looking down at the lead hole K of the back plate 100 , the waterproof structure 600 is not visible in the lead hole K, and the minimum inner diameter of the waterproof structure 600 is greater than the maximum hole diameter of the lead hole K.

[0086] Figure 9 shows a schematic diagram of a partially enlarged cross-sectional structure taken along the BB direction in another embodiment of the photovoltaic assembly shown in Figure 5; Figure 10 shows a schematic top view of the partially enlarged cross-sectional structure shown in Figure 9; for ease of explanation, only the content related to the embodiment of the present application is shown.

[0087] In other embodiments, the inner contour of the orthographic projection of the waterproof structure 600 on the reference surface coincides with the outer contour of the orthographic projection of the lead hole K on the reference surface. That is, as shown in FIG9 and FIG10 , when looking down at the lead hole K of the back plate 100 , the waterproof structure 600 is not visible from the lead hole K, and the contour of the hollow portion of the waterproof structure 600 coincides with the contour of the lead hole K.

[0088] Figure 11 shows a schematic diagram of a partially enlarged cross-sectional structure in the BB direction of another embodiment of the photovoltaic assembly shown in Figure 5; Figure 12 shows a schematic top view of the partially enlarged cross-sectional structure shown in Figure 11; for ease of explanation, only the content related to the embodiment of the present application is shown.

[0089] In some further embodiments, at least a portion of the inner contour of the orthographic projection of the waterproof structure 600 on the reference surface is located within the orthographic projection of the lead hole K on the reference surface. That is, when looking down at the lead hole K of the back plate 100, the waterproof structure 600 is partially exposed in the lead hole K. The inner contour of the orthographic projection of the waterproof structure 600 on the reference surface can be completely located within the orthographic projection of the lead hole K on the reference surface, or it can be partially located within the orthographic projection of the lead hole K on the reference surface and the other portion located within the orthographic projection of the lead hole K on the reference surface. Taking Figures 11 and 12 as examples, it is illustrated that the inner contour of the orthographic projection of the waterproof structure 600 on the reference surface can be completely located within the orthographic projection of the lead hole K on the reference surface, that is, when looking down at the lead hole K of the back plate 100, the hollow portion of the waterproof structure 600 is completely exposed in the lead hole K.

[0090] Therefore, the required waterproof structure 600 can be flexibly set according to the implementation methods in some of the above embodiments.

[0091] In some embodiments, the busbar 400 has a bent portion 402 located upstream of the lead-out end 401 of the busbar 400 along the lead-out direction. In this direction, the bent portion 402 is located between the waterproof structure 600 and the lead-out hole K. Alternatively, the bent portion 402 is located within the waterproof structure 600. The lead-out direction refers to the direction in which the busbar 400 extends toward the lead-out end 401. Figures 7, 8, 9, and 10 illustrate a case where the bent portion 402 is located between the waterproof structure 600 and the lead-out hole K along the lead-out direction. Figures 11 and 12 illustrate a case where the bent portion 402 is located within the waterproof structure 600. It will be appreciated that when the bent portion 402 is located within the waterproof structure 600, the internal location of the busbar 400 provides greater stability. This configuration can be tailored to the specific application and is not specifically limited in this embodiment of the present application.

[0092] Figure 13 shows a schematic diagram of a partially enlarged cross-sectional structure taken along the BB direction in another embodiment of the photovoltaic assembly shown in Figure 5; Figure 14 shows a schematic top view of the partially enlarged cross-sectional structure shown in Figure 13; for ease of explanation, only the content related to the embodiments of the present application is shown.

[0093] In some embodiments, referring to Figures 13 and 14 , the orthographic projection of the lead hole K on the reference surface lies on the orthographic projection of the waterproof structure 600 on the reference surface. That is, the orthographic projection of the waterproof structure 600 on the reference surface can have an outer contour but no inner contour, or alternatively, the orthographic projection of the waterproof structure 600 on the reference surface can have an inner contour, with the outer contour of the orthographic projection of the lead hole K on the reference surface and the inner contour of the orthographic projection of the waterproof structure 600 on the reference surface being independent and non-overlapping. Figures 13 and 14 illustrate a scenario where the orthographic projection of the waterproof structure 600 on the reference surface has an outer contour but no inner contour. In other words, the lead hole K is filled and sealed by the waterproof structure 600. When water vapor attempts to enter the photovoltaic module, it is first blocked by the waterproof structure 600 at the lead hole K. This further enhances the water-blocking capability of the waterproof structure 600.

[0094] Of course, based on the waterproof structure 600 shown in FIG7 , a sealing portion can be filled in the hollow portion of the waterproof structure 600 to form the situation shown in FIG13 . The sealing portion can extend from the inside of the photovoltaic module to the inside of the lead hole K. The material of the sealing portion can be the same as or different from that of the waterproof structure 600, as long as it has water-blocking capabilities. It can be set according to the specific usage situation, and the embodiment of the present application does not impose specific restrictions on this. Accordingly, the lead end 401 of the busbar 400 can pass through the waterproof structure 600, the sealing portion, and the lead hole K in sequence and pass through the backplane 100.

[0095] In some embodiments, referring again to Figures 13 and 14 , the waterproof structure 600 has an exposed surface m exposed to the lead hole K, and the lead end 401 of the busbar 400 extends through the exposed surface m. In other words, the portion of the busbar 400 located within the photovoltaic module near the lead hole K is secured within the waterproof structure 600. This further enhances the stability of the busbar 400.

[0096] In some embodiments, the outer contour of the orthographic projection of the waterproof structure 600 on the reference surface is a regular shape. The regular shape can be a circle, triangle, rectangle, ellipse, trapezoid, or the like. Alternatively, the outer contour of the orthographic projection of the waterproof structure 600 on the reference surface is an irregular shape. The irregular shape can be various shapes formed by enclosing straight lines or curves. The shape of the lead hole K can be regular or irregular. In some embodiments, when the orthographic projection of the waterproof structure 600 on the reference surface has an inner contour, the inner contour of the orthographic projection of the waterproof structure 600 on the reference surface is a regular shape. Alternatively, the inner contour of the orthographic projection of the waterproof structure 600 on the reference surface is an irregular shape. Regular shapes and irregular shapes can also refer to the relevant descriptions in some of the aforementioned embodiments and will not be repeated here.

[0097] Figure 16 shows a schematic diagram of a partially enlarged structure of the photovoltaic assembly shown in Figure 5 in another embodiment; Figure 17 shows a schematic diagram of a partially enlarged structure of the photovoltaic assembly shown in Figure 5 in yet another embodiment; Figure 18 shows a schematic diagram of a partially enlarged structure of the photovoltaic assembly shown in Figure 5 in yet another embodiment; for ease of explanation, only the content related to the embodiments of the present application is shown.

[0098] For example, in the waterproof structure 600 and the wire hole K shown in Figures 7 to 15 , the outer and inner contours of the orthographic projection of the waterproof structure 600 on the reference surface are circular, and the shape of the wire hole K is also circular. In the waterproof structure 600 and the wire hole K shown in Figure 16 , the outer and inner contours of the orthographic projection of the waterproof structure 600 on the reference surface are rectangular, and the shape of the wire hole K is also rectangular. In the waterproof structure 600 and the wire hole K shown in Figure 17 , the outer and inner contours of the orthographic projection of the waterproof structure 600 on the reference surface, and the shape of the wire hole K, are rectangular with chamfered corners. In the waterproof structure 600 and the wire hole K shown in Figure 18 , only the waterproof structure 600 and the wire hole K are shown; the waterproof structure 600 is radiating, and the wire hole K is circular.

[0099] In some embodiments, the waterproof structure 600 is made of rubber, rubber mixture, silicone, silicone mixture, silicone rubber, resin or mixed materials, and the mixed materials include at least one of rubber, rubber mixture, silicone, silicone mixture, silicone rubber and resin.

[0100] It should be noted that the rubber mixture is a mixture with rubber as the main material. As needed, the rubber mixture may contain various additives, fillers, etc., and the silicone mixture can also be understood with reference to the definition of rubber mixture, which will not be repeated here. The mixed material may be doped with at least one of mixed rubber, rubber mixture, silicone, silicone mixture, silicone rubber, and resin. Of course, in other embodiments, the waterproof structure 600 may also be made of hybrid materials, and the hybrid material can achieve the required waterproof level, and the embodiment of the present application does not impose specific restrictions on this. It can be understood that the above-mentioned materials are all existing materials, and the embodiment of the present application does not protect the components of the waterproof structure 600. The above-mentioned structure only utilizes the characteristics of existing materials to achieve a waterproof effect. Those skilled in the art can flexibly choose from existing materials based on the inventive concept of the embodiment of the present application.

[0101] In this way, according to different usage requirements, different materials can be flexibly selected to manufacture the waterproof structure 600 to achieve corresponding waterproof needs.

[0102] In some implementations, the waterproof structure 600 may be in the form of an adhesive tape, an adhesive strip, or a sealant, which may be selected based on specific usage, and is not specifically limited in this embodiment of the present application.

[0103] It should be noted that the photovoltaic assembly in the embodiment of the present application may also include components such as a frame and a junction box, and relevant settings can be made according to specific usage conditions, which will not be described in detail here.

[0104] In summary, the embodiments of the present application sandwich the waterproof structure 600 between the backsheet 100 and the frontsheet 200, allowing the lead ends 401 of the busbar 400 to extend through the lead holes K via the waterproof structure 600, thereby reducing the risk of water vapor entering the interior of the photovoltaic module through the lead holes K. Furthermore, placing the waterproof structure 600 inside the photovoltaic module not only reduces the risk of failure of the waterproof structure 600 due to being located outside the photovoltaic module and being susceptible to external stress, but also utilizes the lamination pressure of the photovoltaic module to rigidly constrain the waterproof structure 600, thereby further tightening the connection between the waterproof structure 600 and the backsheet 100 and frontsheet 200. Furthermore, based on the implementation of the waterproof structure 600 illustrated in some of the above embodiments, the arrangement of the waterproof structure 600 can be flexibly selected to suit the application. This not only significantly improves the water vapor barrier properties of the module at the lead holes K, but also improves the reliability of the waterproof structure 600, thereby reducing the impact on the output power of the photovoltaic module, improving the stability of the photovoltaic module during outdoor use, and enhancing safety performance.

[0105] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A photovoltaic module, comprising: A back plate (100) and a front plate (200) arranged opposite to each other; A battery string (300) is arranged between the back plate (100) and the front plate (200); A bus bar (400) electrically connected to the battery string (300); and A waterproof structure (600) is sandwiched between the back plate (100) and the front plate (200); a lead hole (K) is provided on the back plate (100); the bus bar (400) has a lead end (401), and the lead end (401) passes through the waterproof structure (600) and out of the lead hole (K); The orthographic projection of the lead hole (K) on the reference plane is located within the outer contour of the orthographic projection of the waterproof structure (600) on the reference plane, and the reference plane is a plane parallel to the plane where the lead hole (K) is located.

2. The photovoltaic module according to claim 1, wherein: The inner contour of the orthographic projection of the waterproof structure (600) on the reference surface is located outside the orthographic projection of the lead hole (K) on the reference surface.

3. The photovoltaic module according to claim 1, wherein: The inner contour of the orthographic projection of the waterproof structure (600) on the reference surface coincides with the outer contour of the orthographic projection of the lead hole (K) on the reference surface.

4. The photovoltaic module according to claim 1, wherein: At least part of the inner contour of the orthographic projection of the waterproof structure (600) on the reference surface is located within the orthographic projection of the lead hole (K) on the reference surface.

5. The photovoltaic module according to any one of claims 2 to 4, wherein: The inner contour of the orthographic projection of the waterproof structure (600) on the reference surface is a regular shape.

6. The photovoltaic module according to any one of claims 2 to 4, wherein: The inner contour of the orthographic projection of the waterproof structure (600) on the reference surface is an irregular shape.

7. The photovoltaic module according to any one of claims 2 to 4, wherein: The bus bar (400) has a bent portion (402) located upstream of the lead-out end (401) along the lead-out direction; Along the lead-out direction, the bent portion (402) is located between the waterproof structure (600) and the lead-in hole (K).

8. The photovoltaic module according to any one of claims 2 to 4, wherein: The bus bar (400) has a bent portion (402) located upstream of the lead-out end (401) along the lead-out direction; The bent portion (402) is located inside the waterproof structure (600).

9. The photovoltaic module according to claim 1, wherein: The orthographic projection of the lead hole (K) on the reference plane is located on the orthographic projection of the waterproof structure (600) on the reference plane.

10. The photovoltaic module according to claim 9, wherein: The waterproof structure (600) has an exposed surface (m) exposed to the lead hole (K); The lead-out end (401) extends out of the exposed surface (m).

11. The photovoltaic module according to any one of claims 1 to 10, wherein: The outer contour of the orthographic projection of the waterproof structure (600) on the reference surface is a regular shape.

12. The photovoltaic module according to any one of claims 1 to 10, wherein: The outer contour of the orthographic projection of the waterproof structure (600) on the reference surface is an irregular shape.

13. The photovoltaic module according to any one of claims 1 to 10, wherein: The waterproof structure (600) is made of rubber, rubber mixture, silicone, silicone mixture, silicone rubber, resin or mixed material, and the mixed material includes at least one of rubber, rubber mixture, silicone, silicone mixture, silicone rubber and resin.

14. The photovoltaic module according to any one of claims 1 to 10, wherein: The back plate (100) is a glass plate, a metal composite plate, a composite polymer plate containing a metal film layer, or a composite polymer plate containing an inorganic non-metallic film layer.

15. The photovoltaic module according to any one of claims 1 to 10, wherein: The photovoltaic module also includes a packaging film (500); The battery string (300) is encapsulated in the encapsulation adhesive film (500), and the encapsulation adhesive film (500) is bonded between the back plate (100) and the front plate (200).

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