A photovoltaic module, a solar cell, and a photovoltaic system

Abstract

A photovoltaic module, a solar cell, and a photovoltaic system are disclosed. The photovoltaic module includes multiple solar cell strings; each solar cell string includes multiple solar cells connected in series, and the connecting surface of each solar cell includes stepped protrusions; the platform of the stepped protrusions has multiple spaced-apart main grids; the stepped protrusions of adjacent solar cells interlock and are electrically connected through the main grids. This invention, by designing the interlocking stepped protrusions, allows the solar cells to be connected more tightly, increasing the cell distribution per unit area. This improves the power generation efficiency of the solar panel and reduces stress concentration at overlapping areas, increasing the yield rate. Furthermore, because the main grids are located on the platform, the solar cells receive more light, effectively improving the module efficiency. This invention also provides a solar cell and a photovoltaic system with the above-mentioned beneficial effects.

Description

Technical Field

[0001] This invention relates to the field of new energy development, and in particular to a photovoltaic module, a solar cell, and a photovoltaic system. Background Technology

[0002] In response to the increasingly serious energy crisis and environmental problems, the development and utilization of solar cells have received increasing attention from all sectors of society. Currently, solar photovoltaic modules are becoming increasingly efficient, generally achieved by reducing the non-silicon cost per watt of the module during manufacturing. In existing technologies, adjacent solar cells within the same cell string are mostly connected by laying solder strips along the main grid on the sun-facing side. However, this results in relatively thick solder strips appearing on the sun-facing side of the solar cell, causing front-side shading and reducing the amount of light received by the cell.

[0003] Based on the above problems, those skilled in the art have proposed shingled string bonding technology. Shingled bonding is one of the high-efficiency solar cell arrangement structures. By cutting the cells into small pieces and stacking each piece into a string, the solar cells are connected to each other in a more compact manner, thereby increasing the distribution of cells per unit area and improving the power generation efficiency of the solar panel. However, in shingled string bonding, the edges of adjacent solar cells are pressed together, which leads to excessive stress concentration at the edges of the cells during the module packaging process. This can easily cause microcracks or fragmentation of the silicon wafers, resulting in a low yield.

[0004] Therefore, how to achieve both high yield and low occlusion rate has become a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a photovoltaic module, a solar cell, and a photovoltaic system to solve the problem that low shading rate and high yield rate are mutually exclusive in the prior art.

[0006] To address the aforementioned technical problems, the present invention provides a photovoltaic module comprising multiple solar cell strings;

[0007] The solar cell string includes multiple solar cells connected in series, and the connecting surface of the solar cells includes stepped protrusions; the platform of the stepped protrusions has multiple spaced main grids;

[0008] The stepped protrusions of adjacent solar cells interlock and are electrically connected through the main grid.

[0009] Optionally, in the photovoltaic module, the solar cell further includes a current guide strip, and the main grid is electrically connected to the front grid line of the solar cell through the current guide strip.

[0010] Optionally, in the photovoltaic module, the front grid lines of the solar cell are multiple fine grids that extend in the same direction as the solar cell string.

[0011] Optionally, in the photovoltaic module, the width of the stepped protrusion ranges from 0.2 mm to 2 mm, including the endpoint values.

[0012] Optionally, in the photovoltaic module, each of the stepped protrusions includes 5 to 15 main grids, including endpoint values.

[0013] Optionally, in the photovoltaic module, the main busbar is a silver main busbar.

[0014] Optionally, in the photovoltaic module, adjacent solar cells are bonded together with conductive adhesive.

[0015] Optionally, in the photovoltaic module, adjacent solar cell strings are electrically connected via busbars;

[0016] The busbar is bonded to the platform of the solar cell and connected to the main grid.

[0017] A solar cell, wherein the solar cell is any of the solar cells described above.

[0018] A photovoltaic system comprising photovoltaic modules as described in any of the above.

[0019] The photovoltaic module provided by this invention includes multiple solar cell strings; each solar cell string includes multiple solar cells connected in series, and the connecting surface of each solar cell includes stepped protrusions; the platform of the stepped protrusions has multiple spaced-apart main grids; the stepped protrusions of adjacent solar cells interlock and are electrically connected through the main grids. This invention, by designing the stepped protrusions that can be spliced, allows the solar cells to be connected more tightly, increasing the cell distribution per unit area. This improves the power generation efficiency of the solar panel and, compared to the shingled string bonding technology in the prior art, significantly reduces stress concentration at the overlapping points, reducing microcracks and breakage rates of the solar cells during lamination in the manufacturing process, thus increasing the yield. Furthermore, since the main grids are located on the platform, rather than on the front of the solar cells for mounting solder strips as in the prior art, the absence of solder strip obstruction on the front allows for greater light intake, effectively improving module efficiency and power generation. This invention also provides a solar cell and photovoltaic system with the above-mentioned beneficial effects. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 An exploded view of a solar cell string in one specific embodiment of the photovoltaic module provided in this application;

[0022] Figure 2 A schematic diagram of the structure of the photovoltaic module provided in this application after the solar cells are connected in series in one specific embodiment;

[0023] Figure 3 A schematic diagram of the structure of the solar cell 100 in another specific embodiment of the photovoltaic module provided in this application;

[0024] Figure 4 This is a schematic diagram of the structure of the solar cell 100 in another specific embodiment of the photovoltaic module provided in this application. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] The core of this invention is to provide a photovoltaic module, of which an exploded view of a solar cell string in one specific embodiment is shown below. Figure 1 As shown in the diagram, the structure after series connection is as follows: Figure 2 As shown, this is referred to as Specific Implementation Method 1, and the photovoltaic module includes multiple solar cell strings;

[0027] The solar cell string includes a plurality of solar cells 100 connected in series, and the connecting surface of the solar cells 100 includes a stepped protrusion 110; the platform of the stepped protrusion 110 has a plurality of spaced main grids 111.

[0028] The stepped protrusions 110 of adjacent solar cells 100 interlock and are electrically connected through the main grid 111.

[0029] Specifically, the width of the stepped protrusion 110 ranges from 0.2 mm to 2 mm, including endpoint values ​​such as any one of 0.20 mm, 1.20 mm, or 2.00 mm. Each stepped protrusion 110 includes 5 to 15 main gates 111, including endpoint values ​​such as any one of 5.0, 10.0, or 15.0.

[0030] like Figure 1 As shown, the lower side of the side surface of the solar cell 100 protrudes outward to form the stepped protrusion 110, and a plurality of main grids are disposed on the platform of the stepped protrusion. Figure 1 The black area in the text.

[0031] In addition, the main gate 111 is a silver main gate 111; the silver main gate 111 can be a main gate 111 after silver paste sintering, silver has high conductivity and low internal loss.

[0032] In a preferred embodiment, adjacent solar cells 100 are bonded together with conductive adhesive. The conductive adhesive bonding process is simple and can improve production efficiency.

[0033] Furthermore, adjacent solar cell strings are electrically connected via busbars; the busbars are bonded to the platform of the solar cell 100 and connected to the main grid 111. By bonding, the busbars are connected to adjacent solar cell strings. Compared with the prior art, this makes the busbars move closer to the inside of the solar cell strings, reducing the distance of the busbars protruding from the solar cell strings, thereby further saving space and improving the solar cell light absorption rate per unit area of ​​the module.

[0034] The photovoltaic module provided by this invention includes multiple solar cell strings; each solar cell string includes multiple series-connected solar cells 100, and the connecting surface of each solar cell 100 includes stepped protrusions 110; the platform of each stepped protrusion 110 has multiple spaced main grids 111; the stepped protrusions 110 of adjacent solar cells 100 interlock and are electrically connected through the main grids 111. This invention, by designing the combinable stepped protrusions 110, allows the solar cells 100 to be connected more tightly, thereby increasing the cell distribution per unit area. This improves the power generation efficiency of the solar panel and, compared to the shingled string welding in the prior art, significantly reduces stress concentration at the overlapping points, reducing microcracks and breakage rates of the solar cells 100 during lamination and increasing the yield. Furthermore, since the main grids 111 are located on the platform, rather than on the front of the solar cells for mounting solder strips as in the prior art, the absence of solder strip obstruction on the front allows for greater light intake, effectively improving module efficiency and power generation.

[0035] Based on Specific Embodiment 1, the connection method between the main grid 111 and the front grid line of the solar cell is further defined to obtain Specific Embodiment 2, the schematic diagram of which is shown below. Figure 3 As shown, it includes multiple solar cell strings;

[0036] The solar cell string includes a plurality of solar cells 100 connected in series, and the connecting surface of the solar cells 100 includes a stepped protrusion 110; the platform of the stepped protrusion 110 has a plurality of spaced main grids 111.

[0037] The stepped protrusions 110 of adjacent solar cells 100 interlock and are electrically connected through the main grid 111;

[0038] The front grid lines of the solar cell 100 are multiple fine grids 120 that extend in the same direction as the solar cell string.

[0039] The difference between this specific embodiment and the above specific embodiment is that this specific embodiment limits the arrangement of the front grid lines, while the rest of the structure is the same as the above specific embodiment, and will not be described in detail here.

[0040] Since the present invention eliminates the need for soldering ribbons to be welded to the sun-facing surface of the solar cell, the relatively thick main grid lines used in the prior art to provide a base for the soldering can also be discarded. As shown in this specific embodiment, only the fine grid 120 of the prior art is left, and it is arranged along the extension direction of the solar cell string to reduce the internal resistance when current passes through the solar cell 100. This specific embodiment discards the main grid in the prior art and instead uses the fine grid 120 to complete the current transmission, which greatly reduces the material cost of grid line printing.

[0041] Based on the second specific embodiment, the connection method between the main grid 111 and the front grid line of the solar cell is further defined, resulting in the third specific embodiment, whose solar cell string structure schematic diagram is shown below. Figure 4 As shown, it includes multiple solar cell strings;

[0042] The solar cell string includes a plurality of solar cells 100 connected in series, and the connecting surface of the solar cells 100 includes a stepped protrusion 110; the platform of the stepped protrusion 110 has a plurality of spaced main grids 111.

[0043] The stepped protrusions 110 of adjacent solar cells 100 interlock and are electrically connected through the main grid 111;

[0044] The front grid lines of the solar cell 100 are multiple fine grids 120 that extend in the same direction as the solar cell string;

[0045] The solar cell 100 also includes a flow guide strip 112, and the main grid 111 is electrically connected to the front grid line of the solar cell through the flow guide strip 112.

[0046] The difference between this specific embodiment and the above specific embodiment is that the current guiding strip 112 is added to the solar cell in this specific embodiment. The rest of the structure is the same as the above specific embodiment, and will not be described in detail here.

[0047] In this specific embodiment, the main grid 111 is electrically connected to the front grid line of the solar cell through the current guide strip 112, so that the current no longer needs to pass through the silicon wafer to reach the front grid line, which greatly reduces the internal resistance of the current flowing in the solar cell string, reduces the internal loss of the module, and improves the output power of the module.

[0048] The present invention also provides a solar cell 100, wherein the solar cell 100 is any of the solar cell 100 described above. The photovoltaic module provided by the present invention includes a plurality of solar cell strings; the solar cell strings include a plurality of solar cells 100 connected in series, and the connecting surface of the solar cells 100 includes stepped protrusions 110; the platform of the stepped protrusions 110 has a plurality of spaced-apart main grids 111; the stepped protrusions 110 of adjacent solar cells 100 are interlocked and electrically connected through the main grids 111. This invention, through the design of the stepped protrusions 110 that can be spliced, enables the solar cells 100 to be connected more tightly, thereby increasing the distribution of cells per unit area. On the one hand, this improves the power generation efficiency of the solar panel; on the other hand, compared with the shingled string welding in the prior art, it significantly reduces stress concentration at the overlapping points, thereby reducing the rate of microcracks and breakage of the solar cells 100 during lamination in the manufacturing process and increasing the yield. In addition, since the main grid 111 is set on the platform, rather than on the front of the solar cell for mounting the solder strip as in the prior art, there is no solder strip blocking the front, allowing more light to enter the solar cell, which can effectively improve the module efficiency and increase power generation.

[0049] The present invention also provides a photovoltaic system, the photovoltaic system comprising a photovoltaic module as described in any of the above. The photovoltaic module provided by the present invention comprises a plurality of solar cell strings; the solar cell strings comprise a plurality of solar cells 100 connected in series, the connecting surface of the solar cells 100 comprising stepped protrusions 110; the platform of the stepped protrusions 110 has a plurality of spaced main grids 111; the stepped protrusions 110 of adjacent solar cells 100 are interlocked and electrically connected through the main grids 111. This invention, through the design of the stepped protrusions 110 that can be spliced, enables the solar cells 100 to be connected more tightly, thereby increasing the distribution of cells per unit area. On the one hand, this improves the power generation efficiency of the solar panel; on the other hand, compared with the shingled string welding in the prior art, it significantly reduces stress concentration at the overlapping points, thereby reducing the rate of microcracks and breakage of the solar cells 100 during lamination in the manufacturing process and increasing the yield. In addition, since the main grid 111 is set on the platform, rather than on the front of the solar cell for mounting the solder strip as in the prior art, there is no solder strip blocking the front, allowing more light to enter the solar cell, which can effectively improve the module efficiency and increase power generation.

[0050] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section.

[0051] It should be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0052] The photovoltaic modules, solar cells, and photovoltaic systems provided by this invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of this invention. It should be noted that those skilled in the art can make various improvements and modifications to this invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A photovoltaic module, characterized in that, The photovoltaic module includes multiple solar cell strings; The solar cell string includes multiple solar cells connected in series, and the connecting surface of the solar cells includes stepped protrusions; the platform of the stepped protrusions has multiple spaced main grids; The stepped protrusions of adjacent solar cells interlock and are electrically connected through the main grid; the main grid is not located on the front side of the solar cells, and there are no solder strips on the front side of the solar cells; The solar cell also includes a flow guide strip, and the main grid is electrically connected to the front grid line of the solar cell through the flow guide strip; Adjacent solar cell strings are electrically connected via busbars; The busbar is bonded to the platform of the solar cell and connected to the main grid; The width of the stepped protrusion ranges from 0.2 mm to 2 mm, including the endpoint values; Each of the stepped protrusions includes 5 to 15 of the main gates, including endpoint values.

2. The photovoltaic module as described in claim 1, characterized in that, The front grid lines of the solar cell consist of multiple fine grids extending in the same direction as the solar cell string.

3. The photovoltaic module as described in claim 1, characterized in that, The main gate is a silver main gate.

4. The photovoltaic module as described in claim 1, characterized in that, The adjacent solar cells are bonded together with conductive adhesive.

5. A solar cell, characterized in that, The solar cell is the solar cell used in the photovoltaic module according to any one of claims 1 to 3.

6. A photovoltaic system, characterized in that, The photovoltaic system includes the photovoltaic module as described in any one of claims 1 to 4.

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