A solar cell module

Abstract

The present invention provides a solar cell assembly, comprising: a back plate, a first through hole formed on the back plate; a junction box, the junction box being arranged on the back plate and corresponding to the position of the first through hole; a limit module arranged in the first through hole, the limit module being an insulator, a second through hole being arranged on the limit module, an outer wall of a first end of the limit module abutting against an inner wall of the first through hole at an end away from the junction box, a gap being formed between an outer wall of a second end of the limit module and an inner wall of the first through hole at an end near the junction box; and a bus bar, one end of the bus bar passing through the second through hole and connected to the junction box. The solar cell assembly of the present invention can increase the creepage distance between the bus bar and the bottom edge of the junction box by increasing the gap between the outer wall of the limit module and the inner wall of the first through hole, reduce the width of the junction box, prevent the bus bar from moving, facilitate the installation of the junction box, and prevent leakage tracking or arc discharge on solid insulating materials, thereby ensuring safety.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a solar cell assembly. Background Art

[0002] Large-scale, MW-class, ground-connected photovoltaic power plants are being deployed across regions rich in solar resources, and the application of photovoltaic modules is expanding. With the widespread deployment of MW-class photovoltaic power plants, increasing system voltage to reduce system power losses is an effective measure. Furthermore, with the voltage increase in photovoltaic systems, the safety performance of modules under high system voltages becomes particularly important. IEC standards define creepage distance parameters. Creepage distance is the shortest path measured along the surface of an insulator between two conductive parts, or between a conductive part and the protective interface of the equipment. Photovoltaic modules also have corresponding creepage distance requirements. To prevent tracking or arcing on solid insulation materials at certain system voltages, the creepage distance in modules must consider three components: the distance from the edge of the cell to the long edge of the photovoltaic glass; the distance from the edge of the busbar at the beginning and end of the module to the short edge of the photovoltaic glass; and finally, the distance from the busbar exiting the module along the photovoltaic backsheet or glass to the edge of the junction box.

[0003] In double-glass modules, the busbars are routed through the circular hole in the back glass before being soldered to the split junction box. Typically, the hole is filled with melted EVA (ethylene-vinyl acetate copolymer) or PO (polyolefin) film, a sealing material. The outside of the hole is filled with sealant, securing the junction box and sealing the assembly. Therefore, the minimum creepage distance at this point can only be calculated as a straight line from the edge of the busbar along the sealant-glass interface to the edge of the junction box. To meet the creepage distance requirements at this point, the split junction box must be wider than a certain width. For bifacial double-glass modules, the module size must also be increased to prevent the junction box from obstructing the back cells.

[0004] Existing double-glass photovoltaic modules consist of front glass, encapsulation material, photovoltaic cell strings, encapsulation material, and back glass stacked from bottom to top. In addition, a split junction box is bonded to the back glass, and some types of photovoltaic modules have a surrounding frame to enhance the overall mechanical performance of the module. The encapsulation material, EVA film or PO film, melts during high-temperature lamination and bonds the module glass and cell strings together after cooling, thus providing cross-linking, sealing, insulation, and protection for the cell strings within the module. Double-glass photovoltaic modules use circular holes in the back glass to lead out the busbars for welding to the external photovoltaic junction box. Typically, the melted film will overflow along the circular hole in the glass during lamination, and a separate process is required to clean the overflowed film from the circular hole in the back glass. Improper cleaning during the cleaning process may result in poor welding between the busbar and the junction box. Furthermore, according to the stacking sequence of double-glass photovoltaic modules, the back glass hole must be aligned with the busbar before it can be placed. During the placement process, the busbar can easily shift position, causing the back glass to be misplaced from the previously stacked materials. Even after the back glass is placed, in most cases, the busbar's position shifting within the glass hole causes inconvenience during the subsequent junction box installation. Summary of the Invention

[0005] In view of this, the present invention provides a solar cell assembly.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A solar cell assembly according to an embodiment of the present invention includes:

[0008] a back plate, wherein a first through hole is formed on the back plate;

[0009] a junction box, the junction box being arranged on the back plate and corresponding to the position of the first through hole;

[0010] a limit module disposed in the first through hole, the limit module being an insulator and having a second through hole formed thereon, the outer side wall of the first end of the limit module abutting against the inner side wall of the first through hole at an end away from the junction box, and a gap being formed between the outer side wall of the second end of the limit module and the inner side wall of the first through hole at an end near the junction box;

[0011] A bus bar, one end of which passes through the second through hole and is connected to the junction box.

[0012] Furthermore, the first through hole is a cylindrical through hole, the limiting module is formed in a truncated cone shape, and the outer diameter of the first end of the limiting module is greater than the outer diameter of the second end of the limiting module.

[0013] Furthermore, the outer diameter of the first end of the limiting module is 2-4 mm larger than the outer diameter of the second end of the limiting module.

[0014] Further, in the axial direction along the first through hole, the height of the limiting module is equal to the depth of the first through hole.

[0015] Furthermore, a cavity is defined in the limiting module, the first end of the limiting module is formed as an open end, and the second through hole is formed from the second end of the limiting module and communicates with the cavity.

[0016] Furthermore, the wall thickness of the limiting module is 1 mm.

[0017] Furthermore, the second through holes include two, and the two second through holes are spaced apart and distributed.

[0018] Furthermore, the bus bars include two, and the two bus bars are spaced apart and pass through the corresponding second through holes respectively.

[0019] Furthermore, the two second through holes are respectively formed into a long strip shape, and the two second through holes are symmetrically and parallelly distributed.

[0020] Furthermore, a skirt extending radially outward is formed on the outer side of the first end of the limiting module.

[0021] Furthermore, the skirt stops at the lower surface of the back plate.

[0022] Furthermore, the skirt is formed in a fan shape and extends along the circumference of the first end of the limiting module.

[0023] Furthermore, the skirt includes two edges, and the two edges are symmetrically distributed along the circumference of the first end of the limiting module.

[0024] Furthermore, the busbars include two, one end of the busbar is parallel to the axis of the first through hole, and the other ends of the two busbars are respectively fitted in the gaps between the two skirts.

[0025] Furthermore, the limiting module is formed as a nylon material piece.

[0026] The beneficial effects of the above technical solution of the present invention are as follows:

[0027] According to the solar cell assembly of the present invention, a limiting module is provided in the first through hole of the back plate, the outer side wall of the first end of the limiting module stops at the inner side wall of the first through hole away from the junction box end, and a gap is formed between the outer side wall of the second end of the limiting module and the inner side wall of the first through hole close to the junction box end. By increasing the gap between the outer side wall of the limiting module and the inner side wall of the first through hole, the creepage distance between the bus bar and the bottom edge of the junction box can be increased, the width of the junction box can be appropriately reduced, and the size of the entire solar cell assembly can be reduced at the same time, saving materials, limiting the position of the bus bar, preventing the position of the bus bar from moving and changing, facilitating the subsequent installation of the junction box, and preventing leakage tracking or arc discharge on the solid insulating material, thereby ensuring safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic structural diagram of a limit module according to an embodiment of the present invention;

[0029] Figure 2 A cross-sectional view of the cooperation between the limit module and the back plate according to an embodiment of the present invention;

[0030] Figure 3 A schematic diagram of the cooperation between the limit module and the bus bar according to an embodiment of the present invention;

[0031] Figure 4 Schematic diagram of an explosion of a solar cell assembly according to an embodiment of the present invention;

[0032] Figure 5 A schematic diagram of creepage distance in an existing solar cell module;

[0033] Figure 6 Schematic diagram of creepage distance in a solar cell assembly according to an embodiment of the present invention.

[0034] Reference numerals:

[0035] Solar cell module 200;

[0036] Limiting module 10; chamber 11; second through hole 12; skirt 13;

[0037] Back plate 210; first through hole 211;

[0038] busbar 220;

[0039] Junction box 230. DETAILED DESCRIPTION

[0040] To make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0041] The solar cell assembly 200 according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0042] like Figures 1 to 6 As shown, the solar cell assembly 200 according to an embodiment of the present invention includes a back plate 210 , a limiting module 10 , a bus bar 220 and a junction box 230 .

[0043] Specifically, a first through hole 211 is formed on the back panel 210, the junction box 230 is arranged on the back panel 210 and corresponds to the position of the first through hole 211, the limiting module 10 is arranged in the first through hole 211, the limiting module 10 is an insulator, and a second through hole 12 is provided on the limiting module 10. The outer wall of the first end of the limiting module 10 stops at the inner wall of the first through hole 211 away from the end of the junction box 230, and a gap is formed between the outer wall of the second end of the limiting module 10 and the inner wall of the first through hole 211 close to the end of the junction box 230, and one end of the bus bar 220 passes through the second through hole 12 and is connected to the junction box 230.

[0044] That is, the solar cell module 200 is mainly composed of a back sheet 210, a limit module 10, a bus bar 220, and a junction box 230. The back sheet 210 can be made of glass, polymethyl methacrylate (i.e., organic glass), polyvinyl fluoride composite film (TPT), organic fluorine (TPF), double-sided fluorine (KPK), and other commonly used back sheet materials in modules. A first through hole 211 may be formed on the back plate 210, and the first through hole 211 may be cylindrical. The junction box 230 may be arranged on the back plate 210 and correspond to the position of the first through hole 211. The limiting module 10 may be arranged in the first through hole 211. The limiting module 10 may be an insulator, for example, an insulating plastic part or rubber part. A second through hole 12 may be provided on the limiting module 10, and the second through hole 12 may include multiple, multiple second through holes 12 may be distributed at intervals, and one end of the bus bar 220 may pass through the second through hole 12. The shape and size of the second through hole 12 may be reasonably selected according to the bus bar 220, so that the bus bar 220 can be stably set in the second through hole 12 to prevent the bus bar position from moving deviation and facilitate the connection of the junction box. The outer sidewall of the first end of the limiting module 10 can abut against the inner sidewall of the end of the first through hole 211 away from the junction box 230. A gap is formed between the outer sidewall of the second end of the limiting module 10 and the inner sidewall of the end of the first through hole 211 near the junction box 230. The gap can be roughly in the shape of an inverted triangle, that is, the width of the gap can gradually decrease from top to bottom. One end of the busbar 220 can pass through the second through hole 12 and connect to the junction box 230. The solar cell module 200 can be a photovoltaic double-glass module. In addition, the limiting module 10 can be applicable to both full-cell double-glass modules and half-cell double-glass modules.

[0045] In the solar cell assembly 200 of the present invention, the gap can increase the creepage distance between the bus bar 220 and the bottom edge of the junction box 230. The presence of the gap makes the creepage distance between the bus bar 220 and the bottom edge of the junction box 230 no longer a straight line along the interface between the sealant and the glass. Figure 5 As shown, the existing solar cell assembly mainly includes a bus bar 1, a junction box 2 and a back plate 3. The existing solar cell assembly does not use a limit module 10, and the creepage distance between the bus bar 1 and the bottom edge of the junction box 2 is a; Figure 6 The figure shows a solar cell assembly after using the limiting module 10. The creepage distance between the bus bar 220 and the bottom edge of the junction box 230 in the solar cell assembly is b. Obviously, compared with a, b increases the distance of two straight lines downward along the outer wall of the limiting module 10 and upward along the inner wall of the first through hole 211 on the back panel 210.

[0046] The outer wall of the first end of the limiting module 10 can stop at the inner wall of the first through hole 211, preventing the melted adhesive film from overflowing along the first through hole 211 of the back plate during lamination, thereby avoiding the cleaning operation in the subsequent process. The bus bar 220 can be one or more, and the second through hole 12 can be one or more. A bus bar 220 can be set in each second through hole 12. The junction box 230 can be set on the upper side of the back plate 210 and above the limiting module 10. The bus bar 220 is connected to the junction box 230. The position of the bus bar at the first through hole 211 of the back plate can be limited by the second through hole 12, preventing the position of the bus bar from moving and changing, and facilitating the subsequent connection of the junction box.

[0047] In some embodiments, the first through hole 211 may be a cylindrical through hole, the limiting module 10 may be formed in a truncated cone shape, and the outer diameter of the first end of the limiting module 10 is greater than the outer diameter of the second end of the limiting module 10. Preferably, the outer diameter of the first end of the limiting module 10 is 2-4 mm greater than the outer diameter of the second end of the limiting module 10.

[0048] In other embodiments, the height of the stopper module 10 along the axial direction of the first through-hole 211 is equal to the depth of the first through-hole 211, facilitating installation and mating with the junction box. If the axial height of the stopper module 10 is greater than the axial depth of the first through-hole 211, the stopper module 10 will extend out of the first through-hole 211, making installation and mating with the junction box inconvenient. If the axial height of the stopper module 10 is less than the axial depth of the first through-hole 211, the busbar will be unstable and prone to displacement.

[0049] Preferably, a chamber 11 is defined in the limiting module 10, and the chamber 11 can extend along the axial direction of the limiting module 10. The first end of the limiting module 10 is formed as an open end, and the second through hole 12 is formed from the second end of the limiting module 10 and is connected to the chamber 11. The bus bar 220 can pass through the chamber 11 and out from the second through hole 12 to connect with the junction box 230, so that the bus bar 220 is stable and not prone to position deviation.

[0050] Specifically, the wall thickness of the limiting module 10 is 1 mm, which ensures the strength requirement of the limiting module 10 and can be reasonably selected according to actual conditions without being easily deformed.

[0051] According to some embodiments, the second through holes 12 may include two, and the two second through holes 12 may be spaced apart and distributed. The two second through holes 12 may be located at the center of the end surface of the second end of the limiting module 10, and the spacing distance may be reasonably selected. The busbars may be respectively arranged in the corresponding second through holes 12. For example, there may be two busbars, and the two busbars 220 may be spaced apart and pass through the corresponding second through holes 12. The two second through holes 12 may be used to control the spacing deviation of the two busbars to not exceed 3 mm and the left and right offset to not exceed 1 mm, and to keep the two busbars vertically upward to avoid movement of the positions of the two busbars, thereby facilitating the connection of the junction box.

[0052] Preferably, the two second through holes 12 can be formed into a long strip shape respectively, and the two second through holes 12 can be symmetrically and parallelly distributed, which facilitates the installation of the busbars so that the busbars are spaced apart and parallelly distributed.

[0053] In some embodiments, a skirt 13 extending radially outward may be formed on the outer side of the first end of the limiting module 10. The skirt 13 may extend radially outward from the first end of the limiting module 10. There may be one or more skirts 13, and the plurality of skirts 13 may be spaced apart and evenly distributed along the circumference of the first end of the limiting module 10. The skirt 13 can ensure that when the limiting module 10 is fixed to the inside of the first through hole 211 of the back plate 210, the limiting module 10 is prevented from falling out of the first through hole 211 of the back plate 210 during the lamination process.

[0054] In other embodiments, the skirt 13 may abut against the lower surface of the back plate 210 to maintain the stability of the limiting module 10 and prevent the melted adhesive film from overflowing along the first through hole 211 of the back plate 210 during lamination.

[0055] Optionally, the skirt 13 may be formed in a fan shape and may extend along the circumference of the first end of the limiting module 10 , so that the limiting module 10 remains stable when fixed to the inside of the first through hole 211 of the back plate 210 .

[0056] According to some embodiments, two skirts 13 may be provided, and the two skirts 13 may be symmetrically distributed along the circumference of the first end of the position-limiting module 10. The spacing between the two skirts 13 may be appropriately selected so that the busbar can be positioned between the two skirts 13, thereby limiting the position of the busbar and preventing it from moving. This also facilitates the fit between the position-limiting module 10 and the first through-hole 211 of the backplate 210.

[0057] Preferably, the busbars 220 may include two, one end of the busbar 220 is parallel to the axis of the first through hole 211, and the other ends of the two busbars 220 are respectively fitted in the gap between the two skirts 13 to limit the position of the busbars from moving easily.

[0058] Furthermore, the position limiting module 10 can be formed of a nylon material. The position limiting module 10 can be an integrally formed part. The position limiting module will subsequently need to be laminated in a laminator at approximately 150°C. Therefore, the position limiting module 10 can be made of high-temperature resistant nylon, a high-temperature resistant nylon composite material, or other high-temperature resistant materials, so that the position limiting module 10 can meet the technical requirement of not deforming at a high temperature of 150°C.

[0059] According to the solar cell assembly 200 of the present invention, a limiting module 10 is set in the first through hole 211 of the back plate, and the outer wall of the first end of the limiting module 10 stops at the inner wall of the first through hole 211 away from the end of the junction box, and a gap is formed between the outer wall of the second end of the limiting module 10 and the inner wall of the first through hole 211 close to the end of the junction box. By increasing the gap between the outer wall of the limiting module and the inner wall of the first through hole 211, the creepage distance between the bus bar and the bottom edge of the junction box can be increased, the width of the photovoltaic junction box can be appropriately reduced, and the size of the entire battery assembly can be reduced at the same time, saving materials, limiting the position of the bus bar, preventing the position of the bus bar from moving and changing, and facilitating the subsequent installation of the junction box. Increasing the creepage distance can prevent leakage tracking or arc discharge on the solid insulating material, thereby ensuring safety.

[0060] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar terms used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "a" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "connection" and similar terms are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship also changes accordingly.

[0061] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A solar cell module, characterized in that: include: a back plate, wherein a first through hole is formed on the back plate; a junction box, the junction box being arranged on the back plate and corresponding to the position of the first through hole; a limit module disposed in the first through hole, the limit module being an insulator and having a second through hole formed thereon, the outer side wall of the first end of the limit module abutting against the inner side wall of the first through hole at an end away from the junction box, and a gap being formed between the outer side wall of the second end of the limit module and the inner side wall of the first through hole at an end near the junction box; a bus bar, one end of which passes through the second through hole and is connected to the junction box; In which, a chamber is defined in the limiting module, the first end of the limiting module is formed as an open end, the second through hole is formed from the second end of the limiting module and is connected to the chamber, and a skirt extending radially outward is formed on the outer side of the first end of the limiting module, and the skirt stops at the lower surface of the back plate.

2. The solar cell assembly according to claim 1, wherein The first through hole is a cylindrical through hole, the limiting module is formed in a truncated cone shape, and the outer diameter of the first end of the limiting module is greater than the outer diameter of the second end of the limiting module.

3. The solar cell assembly according to claim 2, wherein: The outer diameter of the first end of the limiting module is 2-4 mm larger than the outer diameter of the second end of the limiting module.

4. The solar cell assembly according to claim 1, wherein In the axial direction along the first through hole, the height of the limiting module is equal to the depth of the first through hole.

5. The solar cell assembly according to claim 1, wherein The wall thickness of the limiting module is 1 mm.

6. The solar cell assembly according to claim 1, wherein The second through holes include two, and the two second through holes are spaced apart and distributed.

7. The solar cell assembly according to claim 6, characterized in that The bus bars include two bus bars, which are spaced apart and pass through corresponding second through holes respectively.

8. The solar cell assembly according to claim 6, wherein: The two second through holes are respectively formed in a strip shape, and the two second through holes are symmetrically and parallelly distributed.

9. The solar cell assembly according to claim 1, wherein The skirt is formed in a fan shape and extends along the circumference of the first end of the limiting module.

10. The solar cell assembly according to claim 1, wherein The skirts include two, and the two skirts are symmetrically distributed along the circumference of the first end of the limiting module.

11. The solar cell assembly according to claim 10, wherein: The bus bars include two, one end of each bus bar is parallel to the axis of the first through hole, and the other ends of the two bus bars are respectively fitted in the gaps between the two skirts.

12. The solar cell assembly according to claim 1, wherein The limiting module is formed of a nylon material.

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