A photovoltaic module and method of manufacture

Abstract

The application discloses a photovoltaic module and a preparation method thereof. The photovoltaic module comprises a laminated unit and a frame wrapping edges of the laminated unit. The laminated unit comprises a laminated unit body and an insulation structure. The laminated unit body comprises a front plate, a first encapsulation adhesive film layer, a cell array, a second encapsulation adhesive film layer and a back plate which are sequentially stacked. The insulation structure is arranged at each side edge of the laminated unit body and comprises an insulation main body segment and a first insulation extension segment which are located between the first encapsulation adhesive film layer and the second encapsulation adhesive film layer. A part of the first insulation extension segment extends to the inside of the laminated unit body and extends to a first target position covering the front surface of the cell array and a second target position covering the back surface of the cell array, respectively. One end of the insulation main body segment is connected with the first insulation extension segment, and the other end of the insulation main body segment extends to the edge of the laminated unit body outside the laminated unit body. In the application, the insulation structure is arranged at each side edge of the laminated unit body, so that the insulation performance is improved, and the creepage distance is prolonged.

Description

Technical Field

[0001] This application belongs to the field of solar cell technology, and in particular relates to a photovoltaic module and its preparation method. Background Technology

[0002] In photovoltaic module assembly, to prevent short circuits caused by direct contact between the frame and the cell array, a gap area of ​​a specific width is usually designed between the cell array and the frame; this area is called the creepage zone. The length of the creepage distance directly affects the insulation performance of the photovoltaic module and its overall lifespan.

[0003] However, due to the limitations of the overall size design and installation space of photovoltaic modules, the width of the creepage zone cannot be increased indefinitely. Therefore, the existing technology uses the following two methods to design the creepage distance: Method 1 involves sealing the edges of double-glass modules with butyl sealant. This method improves the insulation safety requirements of the photovoltaic module's encapsulation structure without reducing the cell area, thereby increasing the cell packing density and ultimately increasing the photovoltaic module's photoelectric conversion efficiency. However, this method requires precise control over the butyl sealant formulation, as it is prone to puncturing each other with the sealant film, damaging the insulation structure and leading to failure. Furthermore, butyl sealant has poor adhesion to the backsheet, making it unsuitable for single-glass modules, and the cost is high.

[0004] Method 2 involves wrapping the photovoltaic modules with insulating tape, effectively extending the creepage distance to the sides and front and back edges of the laminate. However, this method relies on rapid mechanical hot pressing to bond the tape, which can easily create air pockets and lead to insulation failure.

[0005] Therefore, there is an urgent need to provide a photovoltaic module and its manufacturing method to solve the problems mentioned above. Summary of the Invention

[0006] The purpose of this application is to provide a photovoltaic module and its manufacturing method, which can improve insulation performance, extend creepage distance, and thereby increase cell packing density, thus increasing the conversion efficiency of the photovoltaic module.

[0007] This application provides a photovoltaic module, including a laminated unit and a frame surrounding the edge of the laminated unit. The laminated unit includes: a laminated body comprising a front panel, a first encapsulating film layer, a cell array, a second encapsulating film layer, and a back panel stacked sequentially; and an insulating structure disposed on each side of the laminated body and including an insulating main segment and a first insulating extension segment located between the first encapsulating film layer and the second encapsulating film layer. A portion of the first insulating extension segment extends inward into the laminated body and extends to a first target position covering the front side and a second target position covering the back side of the cell array, respectively. One end of the insulating main segment is connected to the first insulating extension segment, and the other end extends outward into the laminated body and to the edge of the laminated body.

[0008] A preferred embodiment is that the first insulating extension segment includes a first top insulating strip, a first bottom insulating strip, and a first connecting insulating strip; the first top insulating strip extends parallel to the surface of the cell array and is located on the back side of the cell array; the first bottom insulating strip extends parallel to the surface of the cell array and is located on the front side of the cell array; the first connecting insulating strip is located outside the edge of the cell array and connects the first top insulating strip and the first bottom insulating strip respectively, wherein the insulating body segment is connected to the first connecting insulating strip.

[0009] A preferred embodiment is that the shape of the first insulating extension includes any one of C-shape, U-shape, and V-shape, and the opening faces the cell array to wrap around the edge of the cell array.

[0010] A preferred embodiment is that the insulation structure further includes: a second insulation extension, which is located outside the edge of each side of the laminate body and wraps around a portion of each side of the laminate body, one end of the second insulation extension is connected to the end of the insulation body segment away from the first insulation extension, and the other end extends toward the front of the laminate body and bends to cover a third target position on the front of the laminate body, or the other end extends toward the back of the laminate body and bends to cover a fourth target position on the back of the laminate body.

[0011] A preferred embodiment is that the second insulating extension includes a second bottom insulating strip and a second connecting insulating strip; the second bottom insulating strip extends parallel to the surface of the laminate body and is located on the front side of the laminate body; the second connecting insulating strip is located on the outer side of the edge of the laminate body, with one end connected to the second bottom insulating strip and the other end connected to the insulating main body segment; or, the second insulating extension includes a second top insulating strip and a second connecting insulating strip; the second top insulating strip extends parallel to the surface of the laminate body and is located on the back side of the laminate body; the second connecting insulating strip is located on the outer side of the edge of the laminate body, with one end connected to the second top insulating strip and the other end connected to the insulating main body segment.

[0012] A preferred embodiment is that the perimeter of the back plate in the laminate body is smaller than that of the front plate, and the projection of the back plate in the thickness direction of the laminate body falls within the range of the front plate, so as to form a stepped side on the outer side of the edge of the laminate body; the inner side of the second connecting insulating strip is fitted with the inner recessed surface of the stepped side, and the outer side is flush with the outer protruding surface of the stepped side.

[0013] A preferred embodiment further includes: a second insulating extension segment located outside the edge of each side of the laminate body and covering the entire area of ​​each side of the laminate body; a portion between the two ends of the second insulating extension segment connects to the insulating body segment; one end of the second insulating extension segment extends toward the front of the laminate body and bends to cover a third target position on the front of the laminate body; and the other end of the second insulating extension segment extends toward the back of the laminate body and bends to cover a fourth target position on the back of the laminate body.

[0014] A preferred embodiment is that the second insulating extension section includes a second top insulating strip, a second bottom insulating strip, and a second connecting insulating strip; the second top insulating strip extends parallel to the surface of the laminate body and is located on the back side of the laminate body; the second bottom insulating strip extends parallel to the surface of the laminate body and is located on the front side of the laminate body; the second connecting insulating strip is located on the outer side of the edge of the laminate body, and its two ends are respectively connected to the second top insulating strip and the second bottom insulating strip, and a portion between the two ends is connected to the insulating main body section.

[0015] A preferred embodiment is that the shape of the second insulating extension includes any one of C-shape, U-shape, and V-shape, and the opening faces the laminate body to wrap around the edge of the laminate body.

[0016] A preferred embodiment is that the insulating main segment, the first insulating extension segment, and the second insulating extension segment all include a substrate layer and an adhesive layer; preferably, the substrate layer is made of at least one of olefin polymers, polyurethane, glass fiber composites, polyimide, polyetherimide, or fluorinated polymers, wherein the olefin polymer is selected from polyolefin homopolymers and / or polyolefin copolymers; preferably, the adhesive layer is made of at least one of polyacrylic acid, polyurethane, epoxy resin, ethylene-vinyl acetate copolymer, polyolefin elastomer, butyl rubber, or polyethersulfone.

[0017] A preferred embodiment is that the thickness of the substrate layer is 80–330 μm; the relative temperature index (RTI) of the substrate layer is ≥90℃, the breakdown voltage is ≥8KV, and the tracking index (CTI) is ≥175V.

[0018] This application also provides a method for preparing the photovoltaic module, comprising the following steps: S1: Lay the front panel and the first encapsulating film layer in sequence; S2: Lay the portion of the first insulating extension section on the first encapsulating film layer that needs to extend to the first target position on the front of the battery cell array; S3: Arrange the battery strings and weld them together to form a battery cell array; S4: Lay the remaining portion of the first insulating extension on the cell array, which extends at least to the second target position on the back of the cell array and connects with the portion laid in step S2; S5: An insulating main body segment is laid on the first encapsulating film layer, with one end connected to the first insulating extension segment and the other end extending to the edge of the first encapsulating film layer. S6: Lay a second encapsulating film layer above the battery cell array, and lay a backing plate above the second encapsulating film layer; S7: The laminated structure is laminated to obtain the laminate body, wherein the insulating main body segment and the first insulating extension segment are located inside the edge of each side of the laminate body and between the first encapsulating film layer and the second encapsulating film layer. The photovoltaic module is obtained after the frame is installed.

[0019] A preferred embodiment includes, after S6 and before S7, the following: A second insulating extension is provided on the outer edge of each edge of the front panel, the first encapsulating film layer, the battery cell array, the second encapsulating film layer, and the back panel. One end of the second insulating extension is connected to the end of the insulating main body segment away from the first insulating extension, and the other end extends toward the front of the front panel and bends to cover a third target position on the front of the front panel, or the other end extends toward the back of the back panel and bends to cover a fourth target position on the back of the back panel; or a portion between the two ends of the second insulating extension is connected to the insulating main body segment, one end of the two ends extends toward the front of the front panel and bends to cover a third target position on the front of the front panel, and the other end of the two ends extends toward the back of the back panel and bends to cover a fourth target position on the back of the back panel.

[0020] Beneficial effects: This application adds an insulating structure to each side of the laminate body. The insulating main segment of this insulating structure is located between the first and second encapsulating film layers at the edge of the laminate body, i.e., at the edge of the cell array. This insulating main segment is considered to provide solid insulation for wrapping the edge of the cell array. A portion of the first insulating extension segment of this insulating structure extends into the laminate body and covers a first target position on the front and a second target position on the back of the cell array, thereby wrapping the edge of the cell array. This first insulating extension segment is considered to extend the creepage distance. The combined design of the insulating main segment and the first insulating extension segment effectively enhances the insulation performance of the photovoltaic module, improves its high-voltage resistance, and thus increases its power output. Furthermore, since the first insulating extension segment is used to extend the creepage distance, the distance between the cell array and the edge of the photovoltaic module glass can be reduced. The freed-up space can be used to increase the cell spacing or cell size, thereby making fuller use of the photovoltaic module area and improving its utilization efficiency. This insulation structure eliminates the need for insulating tape and butyl rubber, thus avoiding the risk of insulation failure due to poor adhesion of insulating tape at the edges of photovoltaic modules, which can cause air bubbles. It also avoids the risk of delamination failure due to poor adhesion between butyl rubber sealant and the backsheet. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the insulation structure setting area in Embodiment 1 of this application; Figure 2 This is a schematic cross-section of the insulating structure disposed inside the side edge of the laminate body in Embodiment 1 of this application. Figure 1 ; Figure 3 This is a partially enlarged schematic diagram of the first insulating extension of the insulating structure wrapping around the edge of the battery cell array in Embodiment 1 of this application; Figure 4This is a schematic cross-section of the insulating structure disposed inside the side edge of the laminate body in Embodiment 1 of this application. Figure 2 ; Figure 5 This is a schematic diagram of creepage distance in the prior art; Figure 6 This is a schematic diagram showing the creepage distance of the insulation structure disposed inside the side edge of the laminate body in Embodiment 1 of this application; Figure 7 This is a schematic diagram of the layer structure of the insulation structure in Embodiment 1 of this application; Figure 8 This is a schematic cross-section of the insulating structure portion located outside the side edge of the laminate body and in a localized area of ​​the wrapped side in Embodiment 2 of this application. Figure 1 ; Figure 9 This is a schematic cross-section of the insulating structure portion located outside the side edge of the laminate body and in a localized area of ​​the wrapped side in Embodiment 2 of this application. Figure 2 ; Figure 10 This is a partially enlarged schematic diagram of the second insulating extension of the insulating structure in Embodiment 2 of this application, bent to the front side of the laminate body; Figure 11 This is a partially enlarged schematic diagram of the second insulating extension of the insulating structure in Embodiment 2 of this application, bent to the back of the laminate body; Figure 12 This is a schematic diagram showing the creepage distance of the insulating structure portion located outside the side edge of the laminate body and in a local area of ​​the wrapped side in Embodiment 2 of this application; Figure 13 This is a cross-sectional schematic diagram of the laminate body in Embodiment 3 of this application; Figure 14 This is a cross-sectional schematic diagram of the insulating structure portion disposed outside the side edge of the laminate body and in a local area of ​​the wrapped side in Embodiment 3 of this application; Figure 15 This is a cross-sectional schematic diagram of the insulating structure portion disposed outside the side edge of the laminate body and covering the entire side area in Embodiment 4 of this application; Figure 16 This is a schematic diagram showing the creepage distance of the insulating structure portion located outside the side edge of the laminate body and in the entire area of ​​the wrapped side in Embodiment 4 of this application.

[0022] Figure Labels 10. Laminated body; 11. Front panel; 12. First encapsulating film layer; 13. Cell array; 131. Edge cell; 132. Conductor; 14. Second encapsulating film layer; 15. Back panel; 20. Insulating structure; 21. Insulating main section; 22. First insulating extension section; 221. First top insulating strip; 222. First bottom insulating strip; 223. First connecting insulating strip; 23. Second insulating extension section; 231. Second top insulating strip; 232. Second bottom insulating strip; 233. Second connecting insulating strip; 30. Substrate layer; 40. Adhesive layer; 50. Stepped side; 51. Inward recessed surface; 52. Outward extended surface. Detailed Implementation

[0023] The technical solutions of this application are further illustrated below through specific embodiments. These specific embodiments do not represent a limitation on the scope of protection of this application. Any non-essential modifications and adjustments made by others based on the concept of this application still fall within the scope of protection of this application.

[0024] As described in the background section, currently, both methods of sealing double-glass modules with butyl rubber or wrapping photovoltaic modules with insulating tape can effectively extend the creepage distance, but both carry the risk of insulation failure.

[0025] In view of this, this application provides a photovoltaic module that, by adding an insulating structure to the edge of each side of the laminate body, extends the creepage distance and avoids the risk of insulation failure caused by poor adhesion of insulating tape at the edge of the photovoltaic module, resulting in air bubbles; on the other hand, it avoids the risk of delamination failure caused by poor adhesion between butyl sealant and backsheet.

[0026] Example 1 The following is a detailed description of a photovoltaic module provided in Embodiment 1: Please refer to... Figure 1 and Figure 2As shown, the photovoltaic module includes a laminated unit and a frame surrounding the edges of the laminated unit. The laminated unit includes a laminated body 10 and an insulating structure 20. The laminated body 10 includes a front panel 11, a first encapsulating film layer 12, a cell array 13, a second encapsulating film layer 14, and a back panel 15, stacked sequentially from bottom to top. The front panel 11 and the back panel 15 constitute encapsulation glass, and the first encapsulating film layer 12 and the second encapsulating film layer 14 constitute encapsulation film. After lamination, the cell array 13, the encapsulation film, and the encapsulation glass are firmly compressed to form a laminated body 10 with an integral structure. The cell array 13 is thus encapsulated by the encapsulation glass and the encapsulation film, enabling the cell array 13 to resist external environmental interference and improving its stability. It should be noted that the cell array 13 generally includes multiple cell strings and busbars. This application does not limit the type of cell string. For example, the cell string includes any of the following: multi-segment cell strings, half-cell cell strings, and full-cell cell strings. Multiple battery strings are connected in series and / or in parallel via busbars, and multiple battery cells are connected between battery strings via solder strips. The edge battery cell 131 refers to the battery cell located at the edge of the battery cell array 13. For ease of explanation, the term edge battery cell 131 will be used in the following description.

[0027] Please refer to Figure 2 and Figure 3 As shown, the laminate body 10 has a square structure, such as a rectangle. The laminate body 10 includes four sides. The insulating structure 20 is disposed on the four sides of the laminate body 10, and may be located inside the edge of each side, or partially inside the edge of each side and partially outside the edge of each side. This embodiment uses one side of the laminate body 10 as an example for illustration. The insulating structure 20 includes an insulating main body segment 21 and a first insulating extension segment 22 located between the first encapsulating film layer 12 and the second encapsulating film layer 14. The insulating main body segment 21 and the first insulating extension segment 22 are located inside the edges of the four sides of the laminate body 10. A portion of the first insulating extension segment 22 extends into the interior of the laminate body 10 and extends to a first target position on the front side and a second target position on the back side of the battery cell array 13, respectively, so that the first insulating extension segment 22 wraps around the edge of the battery cell array 13. One end of the insulating main body segment 21 is connected to the first insulating extension segment 22, and the other end extends outward from the laminate body 10 and extends to the edge of the laminate body 10. It should be noted that when the laminate body 10 is framed, the edge of the laminate body 10 is attached to the inner wall of the frame. The direction from the center to the edge of the laminate body 10 is outward, and the direction from the edge to the center is inward.

[0028] In this embodiment, an insulating structure 20 is provided on each side edge of the laminate body 10. At least a portion of the insulating structure 20 is located inside the edge of the laminate body 10. Generally, the area of ​​the front plate 11, the first encapsulation film layer 12, the second encapsulation film layer 14, and the back plate 15 of the laminate body 10 is larger than that of the cell array 13. There is a gap between the edge of the cell array 13 and the edge of the laminate body 10. The insulating main body segment 21 of the insulating structure 20 is located between the outer edge of the edge cell 131 and the edge of the laminate body 10. The first insulating extension segment 22 provides wrapping solid insulation to the edge of the edge cell 131. Specifically, the two ends of the first insulating extension segment 22 of the insulating structure 20 extend inward toward the laminate body 10 and extend to cover the first target position on the front side and the second target position on the back side of the edge cell 131. The portion of the first insulating extension segment 22 covering the edge cell 131 can be regarded as extending the creepage distance of the edge cell 131 from the edge of the laminate body 10. Therefore, the insulation structure 20 completely covers the edge of the edge cell 131, increasing the distance (i.e., creepage distance) between the edge of the edge cell 131 and the edge of the laminate body 10. This increased creepage distance is equal to the width and thickness of the first insulating extension 22 located on the front or back of the edge cell 131. The combined design of the insulating body segment 21 and the first insulating extension 22 effectively enhances the insulation performance of the photovoltaic module. Simultaneously, due to the increased creepage distance in this application, the distance between the edge cell 131 and the edge of the laminate body 10 can be reduced compared to existing technologies. This frees up space to increase the cell spacing or cell size, thereby making fuller use of the photovoltaic module's area and improving its utilization efficiency. The width of the first insulating extension 22 refers to the dimension projected onto the thickness direction of the laminate body 10 from the inside out or from the outside in.

[0029] Please continue to refer to Figure 2 and Figure 3As shown, in one embodiment, the first insulating extension 22 includes a first top insulating strip 221, a first bottom insulating strip 222, and a first connecting insulating strip 223. The first top insulating strip 221 extends parallel to the surface of the edge battery cell 131 and is located on the back side of the edge battery cell 131. The inner end of the first top insulating strip 221 extends toward the interior of the laminate body 10 to a second target position covering the back side of the edge battery cell 131, and the outer end extends to the edge of the edge battery cell 131. The first bottom insulating strip 222 extends parallel to the surface of the edge battery cell 131 and is located on the front side of the edge battery cell 131. The inner end of the first bottom insulating strip 222 extends toward the interior of the laminate body 10 to a first target position covering the front side of the edge battery cell 131, and the outer end extends to the edge of the edge battery cell 131. The first connecting insulating strip 223 is located outside the outer edge of the edge battery cell 131. Specifically, it extends along the thickness direction of the edge battery cell 131 and its upper and lower ends are respectively connected to the outer ends of the first top insulating strip 221 and the first bottom insulating strip 222, wherein the insulating main body segment 21 is connected to the first connecting insulating strip 223. Thus, the first top insulating strip 221, the first bottom insulating strip 222, and the first connecting insulating strip 223 together wrap the side of the edge battery cell 131, and simultaneously wrap the front and back edges of the edge battery cell 131, especially covering and insulating the conductors 132 on the front and back, such as solder ribbons, busbars, and other conductive components. For example... Figure 2 As shown, when the busbar is located on the outer edge of the battery cell 131 away from the edge, the conductor 132 is only represented as a solder strip. For the back contact battery, the solder strip is located on the back side, and insulation is achieved by covering the solder strip on the back side with the first top insulating strip 221; as shown Figure 4 As shown, for batteries with solder strips on both the front and back, such as TOPCon batteries, insulation is achieved by simultaneously covering the solder strips on both the front and back with a first top insulating strip 221 and a first bottom insulating strip 222. For example... Figure 2 As shown, when the busbar is positioned near the outer edge of the edge cell 131, the conductor 132 represents both the busbar and the solder strip. The busbar is positioned above the solder strip. For a back-contact battery, the busbar and solder strip are located on the back side. Insulation is achieved by simultaneously covering the solder strip and busbar on the back side with the first top insulating strip 221. In this embodiment, a back-contact battery is preferred, with the busbar positioned on the outer edge away from the edge cell 131 as an example. Figure 2 and Figure 4 The conductor 132 in the text refers to the solder strip. Here, the inner end of the first top insulating strip 221 refers to the end extending inward toward the interior of the laminate body 10, and the outer end refers to the end extending inward toward the edge of the laminate body 10. The outer and inner ends of the first bottom insulating strip 222 are similarly defined.

[0030] In one example, the distance between the first target location and the second target location and the side edge of the edge battery cell 131 affects the creepage distance of the edge battery cell 131. Based on this, embodiments of this application limit the distance between the first target location and / or the second target location and the side edge of the edge battery cell 131 to 2-10 mm, for example, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 6.9 mm, 7.4 mm, 8 mm, 9.3 mm, or 10 mm. The specific dimensions can be set according to actual needs. Additionally, depending on actual needs, the first top insulating strip 221 or the first bottom insulating strip 222 can be set to transparent or black; when transparent is selected, the light transmittance is ≥80%.

[0031] For easier understanding, please refer to Figure 5 As shown, in the prior art, the creepage path of a photovoltaic module is from the outer edge of the edge cell 131 to the side of the laminate body 10, i.e., the inner wall of the frame. This creepage distance is denoted as m1. According to existing photovoltaic module design standards, for example, a 1500V system module needs to ensure a creepage distance greater than 10.4mm. In conventional photovoltaic module design, m1 > 10.4mm. Please refer to... Figure 6 As shown, in this embodiment, by setting the first top insulating strip 221 and the first bottom insulating strip 222, the creepage path of the photovoltaic module is changed as follows: Figure 6 As shown by the arrow in the image, Figure 6 The creepage path described herein is based solely on the first bottom insulating strip 222 as an example. The first top insulating strip 221 follows the same principle. Specifically, the creepage path starts from the position where the inner end of the first bottom insulating strip 222 contacts the edge battery cell 131, and flows along the first bottom insulating strip 222, the first connecting insulating strip 223, and the insulating main body segment 21 to the side of the laminate body 10. This creepage distance is equivalent to m3 + m2 + m1, where m3 represents the thickness of the first bottom insulating strip 222 and m2 represents the width of the first bottom insulating strip 222 on the edge battery cell 131. In practice, the creepage distance in this method is greater than m3 + m2 + m1 because there is a rounded transition at the connection between the insulating main body segment 21 and the first connecting insulating strip 223. Therefore, the creepage distance in this embodiment is increased from m1 in the prior art to at least m3 + m2 + m1. The increased creepage distance is the thickness and width of the first bottom insulating strip 222 located on the front side of the edge battery cell 131. Therefore, in this application, the creepage distance can be extended by increasing the width or thickness of the first top insulating strip 221 or the first bottom insulating strip 222. Then, when the creepage distance m3+m2+m1 is greater than 10.4mm, the distance m1 between the edge cell 131 and the edge of the laminate body 10 is reduced, and the cell spacing or cell size is increased. This allows for more efficient use of the photovoltaic module area and improves the utilization efficiency of the photovoltaic module.

[0032] The shape of the first insulating extension 22 may include any one of C-shape, U-shape, and V-shape, and the opening faces the cell array 13 to wrap around the edge of the cell array 13.

[0033] Please refer to Figure 2 As shown, furthermore, the width of the insulating structure 20 ranges from 10mm to 30mm, for example, it can be 10mm, 12mm, 16mm, 18mm, 20mm, 23mm, 25mm, 28mm, or 30mm. Specifically, for example... Figure 2 As shown, the width W1 of the insulation structure 20 is defined as the distance from the inside to the outside or from the outside to the inside of the laminate body 10, which is projected onto the thickness direction of the laminate body 10.

[0034] Please refer to Figure 7 As shown in this embodiment, it should also be noted that the layer structure of the insulating structure 20 includes a substrate layer 30 for insulation and an adhesive layer 40 for bonding and fixing. The substrate layer 30 is made of at least one of olefin polymers, polyurethane, glass fiber composites, polyimide, polyetherimide, or fluorinated polymers, wherein the olefin polymer is selected from polyolefin homopolymers and / or polyolefin copolymers. The adhesive layer 40 is made of at least one of polyacrylic acid, polyurethane, epoxy resin, ethylene-vinyl acetate copolymer, polyolefin elastomer, butyl rubber, or polyethersulfone. In this embodiment, the substrate layer 30 is bonded to the edge battery cell 131 by the adhesive layer 40, which can be fixed by chemical or physical methods such as pressure-sensitive bonding, hot-melt bonding, or thermosetting.

[0035] In one example, the thickness of the substrate layer 30 is 80–330 μm, for example, it can be 80 μm, 100 μm, 110 μm, 125 μm, 180 μm, 230 μm, 270 μm, or 330 μm. The relative temperature index (RTI) of the substrate layer 30 is ≥90℃, the breakdown voltage is ≥8KV, and the tracking index (CTI) is ≥175V.

[0036] Example 2 Please refer to Figure 8 and Figure 9 As shown, the difference between Example 2 and Example 1 is that: The insulating structure 20 further includes a second insulating extension 23, which is located outside the edge of each side of the laminate body 10 and wraps around a portion of each side of the laminate body 10. For example, the second insulating extension 23 wraps around the upper or lower half of the side of the laminate body 10, leaving the corresponding unwrapped portion exposed. One end of the second insulating extension 23 is connected to the end of the insulating body segment 21 away from the first insulating extension 22, and the other end extends toward the front of the laminate body 10 and bends toward the interior of the laminate body 10 to cover a third target position on the front of the laminate body 10, or the other end extends toward the back of the laminate body 10 and bends toward the interior of the laminate body 10 to cover a fourth target position on the back of the laminate body 10. In this embodiment... Figure 8 This embodiment shows the second insulating extension 23 bending and covering the third target location on the front side of the laminate body 10. Figure 9 The second insulating extension 23 is shown bent and covers the fourth target location on the back side of the laminate body 10. (The above is a partial translation of the original text.) Figure 9 In this process, the second insulating extension 23 wraps around part of the side of the laminate body 10 and bends to cover the back of the laminate body 10, i.e. the surface of the back plate 15. This can effectively reduce the decrease in insulation performance caused by the delamination of the second encapsulation film layer 14 on the back and the back plate 15, and can further insulate the side of the laminate body 10.

[0037] Please refer to Figure 8 and Figure 10 As shown, in one example, the second insulating extension 23 includes a second bottom insulating strip 232 and a second connecting insulating strip 233. The second bottom insulating strip 232 extends parallel to the surface of the laminate body 10 and is located at the front edge of the laminate body 10. The second connecting insulating strip 233 and the second bottom insulating strip 232 cover the lower half of the side of the laminate body 10, while the upper half of the side of the laminate body 10 is exposed. The upper end of the second connecting insulating strip 233 is connected to the insulating main body segment 21, and the lower end is connected to the outer end of the second bottom insulating strip 232. Alternatively, please refer to... Figure 9 and Figure 11 As shown, the second insulating extension 23 includes a second top insulating strip 231 and a second connecting insulating strip 233. The second top insulating strip 231 extends parallel to the surface of the laminate body 10 and is located at the back edge of the laminate body 10. The second connecting insulating strip 233 and the second top insulating strip 231 wrap around the upper half of the side of the laminate body 10, while the lower half of the side of the laminate body 10 is exposed. The upper end of the second connecting insulating strip 233 is connected to the second top insulating strip 231, and the lower end is connected to the insulating main body segment 21.

[0038] In one example, the distance between the third or fourth target position and the side of the second connecting insulating strip 233 affects the creepage distance of the edge battery cell 131. Based on this, embodiments of this application limit the distance between the third or fourth target position and the side of the second connecting insulating strip 233 to 2-10 mm, for example, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 6.5 mm, 7.4 mm, 8 mm, 9.5 mm, or 10 mm. The specific dimensions can be set according to actual needs.

[0039] Please refer to Figure 8 and Figure 12 As shown, this embodiment only illustrates the case where the second bottom insulating strip 232 is located on the front side of the laminate body 10, and uses this to explain the creepage path in this embodiment. Figure 12 As shown, the creepage path of the photovoltaic module changes as follows: Figure 12 As shown by the arrow, through the setting of the second insulating extension section 23, the creepage path of the photovoltaic module starts from the position of the inner end of the first top insulating strip 221 contacting the edge of the cell 131, and flows along the first top insulating strip 221, the insulating main body section 21 and the second connecting insulating strip 233 to the frame. The creepage distance is equivalent to m3+m2+m1'+m4. Here, m4 represents the width of the second connecting insulating strip 233. During frame assembly, the edge of the laminate body 10 is assembled inside the frame through the second connecting insulating strip 233. Here, m1' represents the distance from the edge of the edge battery cell 131 to the edge of the laminate body 10. Then, m1'+m4 is equivalent to the distance from the outer edge of the edge battery cell 131 to the inner wall of the frame. In other words, by setting the second insulating extension section 23, the distance between the edge battery cell 131 and the frame can be further increased. Similarly, the creepage distance in this method is actually greater than m3+m2+m1'+m4 because there is an arc transition at the connection between the insulating main body section 21 and the first top insulating strip 221.

[0040] Therefore, in this embodiment, the creepage distance is increased from m1 in the prior art to at least m3+m2+m1'+m4. The increased creepage distance is the thickness and width of the first top-layer insulating strip 221 located on the back of the edge cell 131. Furthermore, the creepage distance in this application only needs to satisfy m3+m2+m1'+m4>10.4mm, which can reduce the distance m1' between the edge cell 131 and the edge of the laminate body 10, thereby increasing the cell spacing or cell size. This allows for more efficient utilization of the photovoltaic module area and improves the photovoltaic module's utilization efficiency.

[0041] Please refer to Figure 8As shown, furthermore, the width of the insulating structure 20 ranges from 10mm to 30mm, for example, it can be 10mm, 12mm, 16mm, 18mm, 20mm, 23mm, 25mm, 28mm, or 30mm. Specifically, for example... Figure 8 As shown, the width W2 of the insulation structure 20 is defined as the distance between the projection of the insulation structure 20 onto the thickness direction of the laminate body 10 from the inside to the outside or from the outside to the inside.

[0042] Example 3 Please refer to Figure 13 and Figure 14 As shown, the difference between Example 3 and Example 2 is that: When the second insulating extension 23 includes a second top insulating strip 231 and a second connecting insulating strip 233, the back plate 15 and the front plate 11 are arranged in a recessed and staggered manner in the horizontal direction. That is, the four-dimensional dimensions of the back plate 15 are slightly smaller than the four-dimensional dimensions of the front plate 11. Similarly, the four-dimensional dimensions of the second encapsulating film layer 14 on the back side are slightly smaller than the four-dimensional dimensions of the first encapsulating film layer 12 on the front side. It can be understood that during the lamination, the four-dimensional edges of the back plate 15 and the four-dimensional edges of the front plate 11 are not aligned. The projection of the back plate 15 in the vertical direction falls within the range of the front plate 11, so as to form a stepped side 50 on the outer side of the edge of the laminate body 10. The stepped side 50 has a recessed surface 51 and an extended surface 52 in the vertical direction. The inner side of the second connecting insulating strip 233 of the second insulating extension 23 is closely attached to the recessed surface 51 of the stepped side 50, and the outer side is basically flush with the extended surface 52 of the stepped side 50.

[0043] When the second insulating extension 23 wraps around a portion of each side of the laminate body 10, the inner surface of the second connecting insulating strip 233 is tightly fitted onto the recessed surface 51 of the stepped side 50, while its outer surface is flush with the extended surface 52 of the stepped side 50. Thus, when the second insulating extension 23 covers the side of the laminate body 10, it precisely fills the gap caused by the recessed back plate 15, making the overall outer side of the laminate body 10 a continuous and flat frame mounting reference surface, facilitating subsequent frame mounting.

[0044] Example 4 Please refer to Figure 15 As shown, the difference between Example 4 and Example 1 is that: The second insulating extension 23 is located outside the edge of each side of the laminate body 10 and covers the entire area of ​​each side of the laminate body 10. A portion between the two ends of the second insulating extension 23 connects to the insulating body section 21. One end of the second insulating extension 23 extends toward the front of the laminate body 10 and bends toward the laminate body 10 to cover a third target position on the front of the laminate body 10. The other end of the second insulating extension 23 extends toward the back of the laminate body 10 and bends toward the laminate body 10 to cover a fourth target position on the back of the laminate body 10. This structure can further reduce the reduction in insulation performance caused by moisture intrusion along the side of the laminate body 10 and further extend the effective creepage distance.

[0045] Please continue to refer to Figure 15 As shown, in one example, the second insulating extension 23 includes a second top insulating strip 231, a second bottom insulating strip 232, and a second connecting insulating strip 233. The second top insulating strip 231 extends parallel to the surface of the laminate body 10 and is located at the back edge of the laminate body 10. The second bottom insulating strip 232 extends parallel to the surface of the laminate body 10 and is located at the front edge of the laminate body 10. The second connecting insulating strip 233 is located outside the edge of the laminate body 10, and its upper and lower ends are respectively connected to the outer ends of the second top insulating strip 231 and the second bottom insulating strip 232, with a portion between the two ends connecting to the insulating main body segment 21. In this embodiment, inside the laminate body 10, the edge of the edge cell 131 is wrapped by the first insulating extension 22, and outside the laminate body 10, the entire edge of the laminate body 10 is wrapped by the second insulating extension 23, further improving the insulation performance of the component and simultaneously extending the creepage distance. Based on the symmetrical distribution of the second top insulating strip 231 covering the back of the laminate body 10, the second bottom insulating strip 232 covering the front of the laminate body 10, and the second connecting insulating strip 233 covering the side of the laminate body 10, the leakage current can be uniformly extended to the second top insulating strip 231 or the second bottom insulating strip 232 along the symmetrical creepage path when it extends along the second insulating extension section 23.

[0046] The shape of the second insulating extension 23 includes any one of C-shaped, U-shaped, and V-shaped, and the opening faces the side of the laminate body 10 to cover the edge of the laminate body 10.

[0047] Similarly, the width of the insulating structure 20 ranges from 10mm to 30mm, for example, it can be 10mm, 12mm, 16mm, 18mm, 20mm, 23mm, 25mm, 28mm, or 30mm. Specifically, for example... Figure 15As shown, the width W3 of the insulation structure 20 is defined as the distance from the inside to the outside or from the outside to the inside of the laminate body 10, which is projected onto the thickness direction of the laminate body 10.

[0048] Please refer to Figure 16 As shown, this embodiment only takes the first bottom insulating strip 222 as an example for explanation. The creepage path of the photovoltaic module is changed as follows: Figure 16 As indicated by the arrows, through the arrangement of the second insulating extension section 23, namely the second top insulating strip 231, the second bottom insulating strip 232, and the second connecting insulating strip 233, the creepage path of the photovoltaic module starts from the position of the inner end contact edge of the cell 131 of the first bottom insulating strip 222, and flows along the first bottom insulating strip 222, the insulating main body section 21, and the second connecting insulating strip 233 to the inner edge of the second bottom insulating strip 232. This creepage distance is equivalent to m3+m2+m1'+m5+m6. Here, m5 represents the height of the second connecting insulating strip 233 between the insulating main body section 21 and the second bottom insulating strip 232; m6 represents the width of the second bottom insulating strip 232 at the front edge of the laminate body 10. Similarly, the actual creepage distance in this method is greater than m3+m2+m1'+m5+m6 because there is an arc transition at the connection between the insulating main body section 21 and the first bottom insulating strip 222. Therefore, the creepage distance in this embodiment is increased from m1 in the prior art to at least m3+m2+m1'+m5+m6. The increased creepage distance is the thickness and width of the first bottom insulating strip 222 on the front side of the edge battery cell 131, the height of the second connecting insulating strip 233 between the insulating main body segment 21 and the second bottom insulating strip 232, and the width of the second bottom insulating strip 232 on the front side of the laminate body 10.

[0049] Therefore, the creepage distance in this application only needs to satisfy m3+m2+m1'+m5+m6>10.4mm, thereby freeing up space to increase the spacing between solar cells or the size of solar cells, thus making fuller use of the area of ​​the photovoltaic module and improving the utilization efficiency of the photovoltaic module.

[0050] In one example, the long and short sides of the photovoltaic module can selectively employ the aforementioned insulation structure 20 to reduce the distance between the cell array 13 and the edge. Depending on the design requirements of the photovoltaic module, this can be applied to various schemes such as single-glass, double-glass, and glassless modules, and can be combined with short A-side frames, no A-side frames, or no frame, to achieve the required creepage distance extension or equivalent replacement while ensuring a good module appearance. Here, the A-side refers to the slot in the frame used to engage the top surface of the laminate unit.

[0051] Example 6 Please refer to Figure 2 , Figure 9 , Figure 15As shown in this embodiment, a method for preparing a photovoltaic module is also provided, comprising the following steps: S1: Lay the front panel 11 and the first encapsulating film layer 12 in sequence; S2: The portion of the first insulating extension 22 that needs to extend to the first target position on the front side of the cell array 13 is laid on the first encapsulating film layer 12; S3: Arrange battery strings and weld them together to form a battery cell array 13; S4: Lay the remaining portion of the first insulating extension 22 on the cell array 13, which extends at least to the second target position on the back of the cell array 13 and connects with the portion laid in step S2. S5: An insulating main body segment 21 is laid on the first encapsulating film layer 12, with one end connected to the first insulating extension segment 22 and the other end extending to the edge of the first encapsulating film layer 12. S6: Lay a second encapsulating film layer 14 above the cell array 13, and lay a backplate 15 above the second encapsulating film layer 14; S7: The laminated structure is laminated to obtain the laminate body 10, wherein the insulating main body segment 21 and the first insulating extension segment 22 are located inside the edge of each side of the laminate body 10 and are located between the first encapsulating film layer 12 and the second encapsulating film layer 14. The photovoltaic module is obtained after the frame is installed.

[0052] In some embodiments, after S6 and before S7, the following is also included: A second insulating extension section 23 is provided on the outer edge of each edge of the front panel 11, the first encapsulating film layer 12, the cell array 13, the second encapsulating film layer 14 and the back panel 15. One end of the second insulating extension section 23 is connected to the end of the insulating body section 21 away from the first insulating extension section 22, and the other end extends towards the front of the front panel 11 and bends to cover the third target position on the front of the front panel 11, or the other end extends towards the back of the back panel 15 and bends to cover the fourth target position on the back of the back panel 15. Alternatively, a portion of the second insulating extension 23 is connected to the insulating main body 21 between its two ends, one end of which extends toward the front of the front panel 11 and bends to cover the third target position on the front of the front panel 11, and the other end of which extends toward the back of the back panel 15 and bends to cover the fourth target position on the back of the back panel 15.

[0053] As such, a second insulating extension section 23 is provided on the side, front or back of the laminate body 10, so that the second insulating extension section 23 partially or completely covers the outer edge of the laminate body 10, thereby further improving the insulation performance of the photovoltaic module.

[0054] For example, a second top insulating strip 231 is bonded to the back edge of the laminate body 10, and a second bottom insulating strip 232 is bonded to the front edge of the laminate body 10, so that the second top insulating strip 231 and the second bottom insulating strip 232 are vertically opposite each other and the side edge of the laminate body 10 is sandwiched between them. A second connecting insulating strip 233 is used to connect the vertically opposite second top insulating strip 231 and the second bottom insulating strip 232 on the side of the laminate body 10, and the second insulating extension 23 completely covers the edge of the laminate body 10.

[0055] It is understood that this application has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this application. Furthermore, based on the teachings of this application, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this application. Therefore, this application is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this application.

Claims

1. A photovoltaic module, characterized in that, The laminate includes a laminate unit and a frame surrounding the edge of the laminate unit, the laminate unit comprising: The laminate body (10) includes a front plate (11), a first encapsulating film layer (12), a battery cell array (13), a second encapsulating film layer (14), and a back plate (15) stacked sequentially. An insulating structure (20) is disposed on each side of the laminate body (10) and includes an insulating main segment (21) and a first insulating extension segment (22) located between the first encapsulating film layer (12) and the second encapsulating film layer (14). A portion of the first insulating extension segment (22) extends into the interior of the laminate body (10) and extends to a first target position on the front side and a second target position on the back side of the battery cell array (13), respectively. One end of the insulating main segment (21) is connected to the first insulating extension segment (22), and the other end extends outward from the laminate body (10) and extends to the edge of the laminate body (10).

2. The photovoltaic module according to claim 1, characterized in that, The first insulating extension (22) includes a first top insulating strip (221), a first bottom insulating strip (222), and a first connecting insulating strip (223); The first top insulating strip (221) extends parallel to the surface of the cell array (13) and is located on the back side of the cell array (13); The first bottom insulating strip (222) extends parallel to the surface of the cell array (13) and is located on the front side of the cell array (13); The first connecting insulating strip (223) is located on the outer edge of the battery cell array (13) and is connected to the first top insulating strip (221) and the first bottom insulating strip (222) respectively, wherein the insulating body segment (21) is connected to the first connecting insulating strip (223). Preferably, the shape of the first insulating extension (22) includes any one of C-shape, U-shape, and V-shape, and the opening faces the battery cell array (13) to wrap around the edge of the battery cell array (13).

3. The photovoltaic module according to claim 1, characterized in that, The insulation structure (20) also includes: The second insulating extension (23) is located outside the edge of each side of the laminate body (10) and wraps around a portion of each side of the laminate body (10). One end of the second insulating extension (23) is connected to the end of the insulating body segment (21) away from the first insulating extension (22), and the other end extends toward the front of the laminate body (10) and bends to cover a third target position on the front of the laminate body (10), or the other end extends toward the back of the laminate body (10) and bends to cover a fourth target position on the back of the laminate body (10).

4. The photovoltaic module according to claim 3, characterized in that, The second insulating extension (23) includes a second bottom insulating strip (232) and a second connecting insulating strip (233); The second bottom insulating strip (232) extends parallel to the surface of the laminate body (10) and is located on the front side of the laminate body (10); The second connecting insulating strip (233) is located on the outer side of the edge of the laminate body (10), and one end is connected to the second bottom insulating strip (232) and the other end is connected to the insulating main body segment (21); Alternatively, the second insulating extension (23) may include a second top insulating strip (231) and a second connecting insulating strip (233); The second top insulating strip (231) extends parallel to the surface of the laminate body (10) and is located on the back side of the laminate body (10); The second connecting insulating strip (233) is located on the outer side of the edge of the laminate body (10), with one end connected to the second top insulating strip (231) and the other end connected to the insulating main body segment (21). Preferably, the perimeter of the back plate (15) in the laminate body (10) is smaller than the perimeter of the front plate (11), and the projection of the back plate (15) in the thickness direction of the laminate body (10) falls within the range of the front plate (11) to form a stepped side (50) on the outer side of the edge of the laminate body (10). The inner side of the second connecting insulating strip (233) is in contact with the inner recessed surface (51) of the stepped side (50), and the outer side is flush with the outer extended surface (52) of the stepped side (50).

5. The photovoltaic module according to claim 1, characterized in that, The insulation structure (20) also includes: A second insulating extension (23) is located outside the edge of each side of the laminate body (10) and covers the entire area of ​​each side of the laminate body (10). A portion between the two ends of the second insulating extension (23) connects to the insulating body segment (21). One end of the second insulating extension (23) extends toward the front of the laminate body (10) and bends to cover a third target position on the front of the laminate body (10). The other end of the second insulating extension (23) extends toward the back of the laminate body (10) and bends to cover a fourth target position on the back of the laminate body (10).

6. The photovoltaic module according to claim 5, characterized in that, The second insulating extension (23) includes a second top insulating strip (231), a second bottom insulating strip (232), and a second connecting insulating strip (233); The second top insulating strip (231) extends parallel to the surface of the laminate body (10) and is located on the back side of the laminate body (10); The second bottom insulating strip (232) extends parallel to the surface of the laminate body (10) and is located on the front side of the laminate body (10); The second connecting insulating strip (233) is located on the outer side of the edge of the laminate body (10), and its two ends are respectively connected to the second top insulating strip (231) and the second bottom insulating strip (232), and a portion between the two ends is connected to the insulating body segment (21). Preferably, the shape of the second insulating extension (23) includes any one of C-shape, U-shape, and V-shape, and the opening faces the laminate body (10) to wrap around the edge of the laminate body (10).

7. The photovoltaic module according to claim 3 or 5, characterized in that, The insulating main body segment (21), the first insulating extension segment (22) and the second insulating extension segment (23) each include a substrate layer (30) and an adhesive layer (40); Preferably, the substrate layer (30) is made of at least one of olefin polymer, polyurethane, glass fiber composite material, polyimide, polyetherimide or fluorinated polymer, wherein the olefin polymer is selected from polyolefin homopolymer and / or polyolefin copolymer; Preferably, the adhesive layer (40) is made of at least one of polyacrylic acid, polyurethane, epoxy resin, ethylene-vinyl acetate copolymer, polyolefin elastomer, butyl rubber or polyethersulfone.

8. The photovoltaic module according to claim 7, characterized in that, The thickness of the substrate layer (30) is 80–330 μm; The substrate layer (30) has a relative temperature index (RTI) ≥ 90℃, a breakdown voltage ≥ 8KV, and a tracking index (CTI) ≥ 175V.

9. A method for preparing a photovoltaic module as described in any one of claims 1-8, characterized in that, Includes the following steps: S1: Lay the front panel (11) and the first encapsulating film layer (12) in sequence; S2: The portion of the first insulating extension (22) that needs to extend to the first target position on the front of the cell array (13) is laid on the first encapsulation film layer (12); S3: Arrange the battery strings and weld them together to form a battery cell array (13); S4: Lay the remaining portion of the first insulating extension (22) on the cell array (13), which extends at least to the second target position on the back of the cell array (13) and connects with the portion laid in step S2; S5: An insulating main body segment (21) is laid on the first encapsulating film layer (12), one end of which is connected to the first insulating extension segment (22) and the other end extends to the edge of the first encapsulating film layer (12); S6: A second encapsulation film layer (14) is laid on top of the battery cell array (13), and a backplate (15) is laid on top of the second encapsulation film layer (14); S7: The laminated structure is laminated to obtain the laminate body (10), wherein the insulating main body segment (21) and the first insulating extension segment (22) are located inside the edge of each side of the laminate body (10) and between the first encapsulation film layer (12) and the second encapsulation film layer (14). The photovoltaic module is obtained after the frame is installed.

10. The method for preparing a photovoltaic module according to claim 9, characterized in that, After S6 and before S7, it also includes: A second insulating extension (23) is provided on the outer edge of each edge of the front panel (11), the first encapsulating film layer (12), the battery cell array (13), the second encapsulating film layer (14), and the back panel (15). One end of the second insulating extension (23) is connected to the end of the insulating main body section (21) away from the first insulating extension (22), and the other end extends toward the front of the front plate (11) and bends to cover the third target position on the front of the front plate (11), or the other end extends toward the back of the back plate (15) and bends to cover the fourth target position on the back of the back plate (15). Alternatively, a portion of the second insulating extension (23) is connected between the two ends of the insulating main body section (21), one end of which extends toward the front of the front plate (11) and bends to cover the third target position on the front of the front plate (11), and the other end of which extends toward the back of the back plate (15) and bends to cover the fourth target position on the back of the back plate (15).

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