Solar cell module

Abstract

The utility model relates to the technical field of solar cells, and discloses a solar cell module, which comprises a cell string formed by connecting a plurality of cells arranged in an array, a bus bar used for connecting the cells, a back plate used for bearing the cell string and a junction box arranged on the back plate, and the junction box is provided with a wiring port; the bus bar comprises a first section and a second section connected with the first section, the second section comprises a second section body and a folding structure formed by folding the second section body in the length direction of the second section body, and the second section penetrates through the wiring port to be electrically connected with the junction box. According to the utility model, the width of the second section is narrowed, the second section passes through the wiring port and is electrically connected with the junction box, the sectional area of the bus bar can be ensured to be unchanged, and the stable performance of the solar cell module is maintained.

Description

Technical Field

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

[0002] With the rapid development of science and technology, the green and renewable energy industry has experienced rapid growth in recent years. Solar energy is a renewable resource, and solar cell technology, which utilizes the photovoltaic effect to generate electricity, has attracted considerable attention. The application of solar cell modules is becoming increasingly widespread, and solar power generation can be seen everywhere, from traditional large-scale solar power stations to small civilian systems.

[0003] A solar cell module consists of cells, busbars, solder ribbons, and a junction box. One end of the busbar connects to the cells, primarily collecting the current generated by the solar cells. The other end of the busbar runs from the front of the solar cell module to the back, passing through the junction box and connecting to it. This connects the multiple cells in the solar cell module in series or parallel, collecting the current, which is then output to the external circuit through the junction box. Therefore, the junction box is a key component in various power generation systems built with solar cell modules.

[0004] During actual production, when busbars pass through junction boxes with silicone sealant at the bottom, silicone often sticks to the busbar's soldering area, resulting in a cold joint between the busbar and the pads inside the junction box, increasing the risk of diode breakdown in the photovoltaic module. Furthermore, the smaller size of the junction box's wiring port reduces the overall volume and footprint, making it easier to achieve a good seal, thereby improving the junction box's waterproof performance and protecting the internal circuitry from moisture and water. Wider busbars can carry greater current and have lower resistance, helping to reduce energy loss during power transmission and improve the efficiency of solar cell modules. Therefore, the busbar width is often larger than the junction box's wiring port. Conventional methods involve cutting the busbar width to ensure smooth passage through the port and connection to the junction box. However, narrowing the busbar increases resistance, which increases power loss during energy transmission. The narrowed portion also needs to carry greater current, generating more heat, potentially leading to localized overheating and affecting the performance and life of the module. Utility Model Content

[0005] The technical problem to be solved by the present invention is to provide a solar cell assembly, in which the second section of the busbar can smoothly pass through the wiring port and be electrically connected to the junction box, while also ensuring that the cross-sectional area of ​​the busbar remains unchanged, thereby maintaining stable performance of the solar cell assembly.

[0006] In order to solve the above technical problems, the first aspect of the present invention provides a solar cell assembly, comprising: a battery string formed by connecting a plurality of battery cells arranged in an array, a bus bar for connecting the battery cells, a back plate for supporting the battery string, and a junction box provided on the back plate, wherein the junction box is provided with a wiring port;

[0007] The busbar includes a first section and a second section connected to the first section, the second section includes a second section body and a folded structure formed by folding the second section body along its length direction, so that the second section passes through the wiring port and is electrically connected to the junction box.

[0008] As an improvement of the above solution, the second segment is connected to part of the first segment, and the part of the second segment that is not connected to one end of the first segment is folded to form the folded structure, and the width of the second segment body is greater than or equal to the width of the folded structure.

[0009] As an improvement to the above solution, one end of the first section is bent into a second section along a direction perpendicular to the plane of the solar cell assembly, and the second section is connected to a portion of the first section at the bending point.

[0010] As an improvement to the above solution, the ratio of the area of ​​the folded structure to the area of ​​the second section body is 1:(2-5).

[0011] As an improvement to the above solution, the shape of the folding structure is one of a triangle, a rectangle, a square, a trapezoid, and a rhombus.

[0012] As an improvement to the above solution, the width of the first section is greater than the width of the second section body.

[0013] As an improvement to the above solution, the width of the first section is 2 mm to 20 mm;

[0014] The busbar has a thickness of 0.05 mm to 0.5 mm.

[0015] As an improvement to the above solution, a welding pad is further provided on the junction box, and the second section body and the folded structure are welded to the welding pad.

[0016] As an improvement to the above solution, in the first direction, the battery cells between adjacent battery strings are stacked in sequence, and the busbars are arranged at the stacking positions of adjacent battery strings and are in direct contact with the battery cells.

[0017] As an improvement to the above solution, the bus bar is further provided at the end of the battery string and is in direct contact with the battery cells.

[0018] The implementation of this utility model has the following beneficial effects:

[0019] In the present invention, the busbar includes a first section and a second section connected to the first section. The second section includes a second section body and a folded structure formed by folding the second section body along its length, allowing the second section to pass through the wiring port and be electrically connected to the junction box. The folded structure narrows the width of the second section, making the width of the first section greater than the width of the second section body. This not only facilitates the second section's passage through the wiring port and electrical connection to the junction box, but also ensures that the cross-sectional area of ​​the busbar remains unchanged, thereby maintaining its current carrying capacity and helping to maintain the stable performance of the solar cell module. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 : A schematic structural diagram of the front side of a solar cell module in the present invention;

[0021] Figure 2 : A schematic structural diagram of the back side of a solar cell module in the present invention;

[0022] Figure 3 : Figure 1 Lateral view of area A in the middle;

[0023] Figure 4 : Schematic diagram of the connection between the bus bar and the junction box in the utility model;

[0024] Figure 5 : A schematic diagram of the structure of the busbar in the utility model;

[0025] Figure 6 : A schematic diagram of the connection between the first section and the second section of the busbar of the present invention;

[0026] Figure 7 : Schematic diagram of the folding process of the folding structure in the busbar of the present invention;

[0027] Figure 8 : A schematic diagram of the structure of the busbar of the utility model after the folding structure is completely folded;

[0028] Figure 9 : A schematic structural diagram of the front side of another solar cell assembly in the present invention.

[0029] Reference numerals:

[0030] 1-battery string; 2-busbar; 21-first section; 22-second section; 221-second section body; 222-folding structure; 3-back plate; 4-junction box; 41-junction port; 5-metal frame; W1-width of the junction port; W2-width of the first section of the busbar; H-thickness of the busbar. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail with reference to specific embodiments below.

[0032] In order to make the purpose, technical solutions and advantages of the present application more clear, the present application is further described in detail below with reference to the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application. In addition, it should be understood that the specific embodiments described herein are merely used to explain the present application and are not intended to limit the present application.

[0033] In the description of this application, it should be understood that the terms "upper", "lower", "back", "front", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on this application.

[0034] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0035] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0036] The disclosure below provides many different embodiments or examples for realizing different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numbers and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those skilled in the art will appreciate the application of other processes and / or the use scenarios of other materials.

[0037] References herein to "embodiments" or "implementations" mean that a particular feature, component, or characteristic described in connection with an embodiment or implementation may be included in at least one embodiment of the present application. The appearance of such phrases in various places in the specification does not necessarily refer to the same embodiment, nor do they constitute independent or alternative embodiments that are mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0038] In order to solve the above problems, the first aspect of the present invention provides a solar cell assembly, such as Figure 1 and 2 As shown, it includes: a battery string 1 formed by connecting a number of battery cells arranged in an array, a bus bar 2 for connecting the battery cells, a backplane 3 for supporting the battery string 1 and a junction box 4 arranged on the backplane 3, and the junction box 4 is provided with a wiring port 41.

[0039] The junction box 4 is mounted on the backsheet 3 of the solar cell module and can be secured to the backsheet 3 by bonding, welding, or the like. Bonding can be achieved by adhesive, tape, or the like. The width W1 of the connection port 41 of the junction box 4 is generally a maximum of 6 mm. The shape of the connection port 41 can be square, circular, or elliptical, and is not specifically limited in the present invention. It is understood that the junction box 4 does not need to be provided with the connection port 41, as long as the busbar 2 can pass through and be electrically connected to the junction box 4.

[0040] like Figure 3 and Figure 4 As shown, the busbar 2 includes a first section 21 and a second section 22 connected to the first section 21. The first section 21 is arranged on the light-receiving surface of the solar cell string 1 and is wound around the back plate 3 to collect the current generated by the solar cell string 1 and conduct it from the back plate 3. The second section is arranged in a direction perpendicular to the plane of the solar cell assembly and is electrically connected to the junction box 4 through the wiring port 41 to output the generated current to the external circuit through the junction box 4.

[0041] like Figure 5 As shown, the second segment 22 includes a second segment body 221 and a folding structure 222 formed by folding the second segment body 221 along its length. The provision of the folding structure 222 narrows the width of the second segment 22, making the width W2 of the first segment 21 greater than the width of the second segment body 221. This not only facilitates the second segment 22 to pass through the wiring port 41 and electrically connect to the junction box 4, but also ensures that the cross-sectional area of ​​the busbar 2 remains unchanged, thereby maintaining the current carrying capacity and helping to maintain the stable performance of the solar cell module. The provision of the folding structure 222 makes the width W2 of the first segment 21 greater than the width of the second segment body 221. The width of the second segment 22 can be close to the width allowed by the wiring port 41, or can be smaller than the width allowed by the wiring port 41. Optionally, the width W2 of the first section 21 is 2 mm to 20 mm, which can provide a larger current channel, allow more current to pass evenly, and effectively alleviate the heating problem caused by excessive current. Moreover, a proper increase in the width W2 of the first section 21 can also reduce resistance, thereby reducing energy loss and improving the efficiency of the battery assembly.

[0042] Furthermore, the second section 22 is connected to a portion of the first section 21, and the portion of the second section 22 that is not connected to one end of the first section 21 is folded to form the folded structure 222. Specifically, Figures 6 to 8As shown, one end of the first segment 21 is bent along a direction perpendicular to the plane of the solar cell assembly to form a second segment 22, and the second segment 22 is connected to a portion of the first segment 21 at the bending point. In some embodiments, as Figure 6 As shown, the connecting portion of the second segment 22 and the first segment 21 can be cut (red line) to connect the second segment 22 with a portion of the first segment 21. There are multiple options for specific cutting methods, including but not limited to mechanical cutting, laser cutting, plasma cutting, chemical etching, and wire cutting. Subsequently, as shown in FIG. Figure 7 As shown, the unconnected portion is folded to form a busbar 2 having a structure as shown in FIG. Figure 8 shown.

[0043] Optionally, the second section 22 is connected to a portion of the first section 21. The connected portion may be continuous, or the connected portion may be alternately arranged with the unconnected portion. The specific length of the connected portion may be adjusted according to the width W1 of the wiring port in the junction box 4 and the requirements of the required folding structure 222, and is not specifically limited in this application.

[0044] It is understood that the connection structure of the second section 22 differs from that of the first section 21, and the shape of the folded structure 222 may be adjusted accordingly. Optionally, the folded structure 222 is shaped like a triangle, a rectangle, a square, a trapezoid, or a rhombus. Of course, the folded structure 222 may also be irregular. If the shape of the folded structure 222 is too complex, it will inevitably increase the curved surface of the second section 22, which will in turn require the current to pass through a more complex path, increase the resistance in the circuit, and reduce the photoelectric conversion efficiency of the solar cell module.

[0045] Preferably, the width of the second section body 221 is greater than or equal to the width of the folding structure 222, so as to avoid the width of the busbar 2 from being sharply narrowed and the cross-sectional area from being reduced, which may lead to the inability to safely transmit current under high current conditions, increase the risk of electrical failure, and cause local overheating, affecting the long-term stability and life of the battery assembly.

[0046] Furthermore, the ratio of the area of ​​the folding structure 222 to the area of ​​the second section body 221 is of great significance to the battery performance. The ratio of the area of ​​the folding structure 222 to the area of ​​the second section body 221 is 1:(2~5). If the area of ​​the folding structure 222 is too large, it will cause local overheating of the second section 22, and the heat dissipation performance of the battery cell will be reduced. In addition, it will cause uneven current distribution at the connection between the second section 22 and the first section 21, which may produce different working conditions in different areas of the battery module, thereby affecting the long-term working stability and life of the solar cell. If the area of ​​the folding structure 222 is too small, it cannot be guaranteed that it can pass through the wiring port 41 smoothly, or the folding structure cannot be fixed on the junction box 4, resulting in poor electrical contact and reducing the overall power output of the solar cell module. Take the shape of the folding structure 222 as an example, which is a rectangle. Please refer to Figure 5 The length of the folding structure 222 is a1, the width is b1, and the area is S1, S1=a1*b1, the length of the second section body 221 is a2, the width is b2, and the area is S2, S2=a2*b2, b1<b2, S1=(2~5)S.

[0047] Furthermore, the thickness of the busbar 2 is H, and the thickness H of the busbar 2 is 0.05mm~0.5mm. Controlling the thickness H of the busbar 2 to 0.05mm~0.5mm not only has smaller electrons and higher current density, but also is not easy to deform when the second section 22 is folded, thereby avoiding the weakening of the current carrying capacity of the folded part. At the same time, it can also ensure that the folding structure 222 has a certain supporting strength, increase the local heat dissipation performance, and is more easily deformed or damaged under mechanical stress. It can also be fixed in the installation box together with the second section body 221, thereby reducing the loss of electric energy and improving the efficiency of the battery assembly.

[0048] In some embodiments, the junction box 4 is further provided with a soldering pad, to which the second segment body 221 and the folded structure 222 are welded (not shown). Specifically, after the second segment body 221 and the folded structure 222 are inserted into the junction box 4 through the connection port 41, they can first be secured by a fixing device in the junction box 4, and then soldering can be performed on the soldering pad to electrically connect the busbar 2 to the junction box 4. The soldering pad can be made of a variety of materials, including but not limited to copper, solder paste, nickel, silver, and aluminum. The shape of the soldering pad can be circular, square, or other shapes, and the size of the soldering pad can be appropriately adjusted based on the size of the junction box 4 and the number of soldering pads. This application does not impose specific restrictions on the material, size, or number of the soldering pads. Laser scanning welding can be used for the welding. Optionally, the material of the busbar 2 is the same as that of the soldering pad. Having the same material allows for a higher degree of integration between the busbar 2 and the soldering pad, thereby enhancing the reliability of the soldering between the busbar 2 and the soldering pad and reducing the probability of desoldering between the busbar 2 and the soldering pad. In other embodiments, the material of the bus bar 2 is different from the material of the pad. For example, the material of the pad is copper, and the material of the bus bar 2 is aluminum.

[0049] Alternatively, see Figure 9 In the first direction, the battery cells between adjacent battery strings 1 are stacked in sequence. Specifically, the battery cells can be connected in series through welding strips to form battery strings 1 arranged in sequence. The busbars 2 are arranged at the stacking positions of adjacent battery strings 1 and are in direct contact with the battery cells. This can reduce the length of the current path, thereby reducing the series resistance and improving the electrical performance of the component. In addition, the busbars 2 at the stacking position can provide additional mechanical support for the battery cells and enhance the structural stability of the component. At this time, the number of the junction boxes 4 can be three, each connected to the middle busbar 2. The number of the junction boxes 4 can also be more, and the junction boxes 4 can be arbitrarily arranged in the backplane 3 according to actual conditions. In some embodiments, the busbars 2 are also arranged at the ends of the battery string 1 and are in direct contact with the battery cells. The ends are the head end and the tail end in the first direction.

[0050] Preferably, the back panel 3 can protect and support the battery string 1, and has reliable insulation, water resistance and aging resistance. The back panel 3 can have multiple options, usually tempered glass, organic glass, aluminum alloy TPT composite film, KPC, CPC, etc., which can be specifically set according to specific circumstances and is not specifically limited in this application.

[0051] It is understandable that the solar cell assembly may also include a metal frame 5, a front plate (not shown in the figure) and an adhesive film (not shown in the figure). The front plate, such as photovoltaic glass, may be covered on the adhesive film on the light-receiving surface of the cell string 1. The front plate may be ultra-white glass, which has high light transmittance, high transparency, and excellent physical, mechanical and optical properties. For example, the light transmittance of ultra-white glass may be above 92%, which may protect the cell without affecting the efficiency of the back-contact solar cell as much as possible. At the same time, the adhesive film may bond the front plate and the cell string 1 together, and the adhesive film may seal, insulate, and waterproof and moisture-proof the cell string 1. The whole composed of the back plate 3, the cell string 1, the adhesive film and the front plate may be set on the metal frame 5. The metal frame 5 serves as the main external support structure of the entire solar cell assembly and may provide stable support and installation for the solar cell assembly. For example, the solar cell assembly may be installed at the desired location through the metal frame 5.

[0052] The above disclosure is only a preferred embodiment of the present invention and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope covered by the present invention.

Claims

1. A solar cell module, characterized in that: include: A battery string formed by connecting a number of battery cells arranged in an array, a bus bar for connecting the battery cells, a backplane for supporting the battery string, and a junction box provided on the backplane, wherein the junction box is provided with a wiring port; The busbar includes a first section and a second section connected to the first section, the second section includes a second section body and a folded structure formed by folding the second section body along its length direction, so that the second section passes through the wiring port and is electrically connected to the junction box.

2. The solar cell assembly according to claim 1, wherein The second section is connected to a portion of the first section, and a portion of the second section not connected to one end of the first section is folded to form the folded structure. The width of the second section body is greater than or equal to the width of the folded structure.

3. The solar cell assembly according to claim 2, wherein: One end of the first section is bent along a direction perpendicular to the plane of the solar cell assembly to form a second section, and the second section is connected to a portion of the first section at the bending point.

4. The solar cell assembly according to claim 1, wherein The ratio of the area of ​​the folded structure to the area of ​​the second section body is 1:(2-5).

5. The solar cell module according to claim 1, wherein The shape of the folding structure is one of a triangle, a rectangle, a square, a trapezoid, and a rhombus.

6. The solar cell assembly according to claim 2, wherein: The width of the first section is greater than the width of the second section body.

7. The solar cell assembly according to claim 6, wherein The width of the first section is 2 mm to 20 mm; The busbar has a thickness of 0.05 mm to 0.5 mm.

8. The solar cell module according to claim 1, wherein The junction box is further provided with a welding pad, and the second section body and the folding structure are welded to the welding pad.

9. The solar cell module according to claim 1, wherein In a first direction, the battery cells between adjacent battery strings are stacked in sequence, and the busbars are disposed at stacking positions of adjacent battery strings and in direct contact with the battery cells.

10. The solar cell module according to claim 1, wherein The bus bar is also disposed at an end of the battery string and is in direct contact with the battery cells.

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