A photovoltaic module

Abstract

The application relates to the photovoltaic technical field, in particular to a photovoltaic module which comprises cell pieces, welding strips and buffer pieces. A plurality of the cell pieces are arranged along a first direction, and the projections of two adjacent cell pieces along a second direction have an overlapping area. The cell pieces have a plurality of welding pads distributed along the first direction, and the welding pads include edge welding pads located at the outermost sides in the first direction. Two adjacent cell pieces are connected through a welding strip, and the welding strip is connected with the welding pads. Along the first direction, the buffer piece is located between the edge welding pad and the edge of the cell piece, and along the second direction, the buffer piece is located between the welding strip and the cell piece on at least one side of the welding strip. In the application, the buffer piece plays a buffering and protecting role between the welding strip and the cell piece, so that the inter-cell piece stress is dispersed, the risk of cell piece hidden cracking is reduced, and the service life of the photovoltaic module is improved.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic technology, and in particular to a photovoltaic module. Background Technology

[0002] Photovoltaic modules can directly convert solar radiation energy into electrical energy, mainly based on the photovoltaic effect of crystalline silicon. When the photons of sunlight are absorbed by the semiconductor crystalline silicon, electron-hole pairs are generated. When these electron-hole pairs reach the pn junction composed of p-type and n-type crystalline silicon, they are separated to both sides of the pn junction by the junction electric field. When an external load is connected, a photocurrent is formed, and electrical energy is output.

[0003] Photovoltaic modules consist of solar cells and solder ribbons, which connect the cells in strings. Adjacent cells partially overlap to increase the effective light-absorbing area and power output of the module. However, during the lamination process, the stress between the cells is significant, which can easily lead to microcracks in the cells. Utility Model Content

[0004] This application provides a photovoltaic module to solve the technical problem that high inter-cell stress during lamination can easily lead to microcracks in the cells.

[0005] This application provides a photovoltaic module, which includes solar cells, solder ribbons, and a buffer. A plurality of solar cells are arranged along a first direction, and the projections of adjacent solar cells along a second direction overlap. Each solar cell has a plurality of solder pads distributed along the first direction, including an outermost edge solder pad located in the first direction. Adjacent solar cells are connected by solder ribbons, which are connected to the solder pads. Along the first direction, the buffer is located between the edge solder pads and the edge of the solar cell; along the second direction, the buffer is located between the solder ribbon and at least one side of the solar cell.

[0006] In one possible design, along the first direction, at least one side of the solar cell is provided with a busbar, the busbar being located between the edge pad and the edge of the solar cell; Along the first direction, the buffer is located between the busbar and the edge of the battery cell.

[0007] In one possible design, the solar cell has fine grids extending in a third direction, and the buffer is located between the outermost fine grids and the edge of the solar cell.

[0008] In one possible design, the manifold has a manifold gap, and at least a portion of the buffer is located within the manifold gap.

[0009] In one possible design, the battery cell is provided with fine grids extending in a third direction. The fine grids include a first fine grid and a second fine grid that contact the busbar. The first fine grid extends through the busbar gap, while the second fine grid does not extend through the busbar gap. The outermost fine grid is the second fine grid, and the buffer is located between the outermost first fine grid and the edge of the battery cell. Alternatively, the outermost fine grid is the first fine grid, and the buffer is located on the side of the outermost first fine grid away from the edge of the battery cell.

[0010] In one possible design, the projection of the buffer along the second direction lies within the overlapping area.

[0011] In one possible design, the cushioning element is thermosetting adhesive.

[0012] In one possible design, the curing reaction temperature of the buffer is equal to or lower than the welding temperature between the solder strip and the solder pad.

[0013] In one possible design, along the second direction, the thickness H of the buffer element satisfies: 100μm≤H≤200μm.

[0014] In one possible design, along the direction perpendicular to the second direction, the dimension d of the buffer element satisfies: 0.5mm ≤ d ≤ 1.5mm.

[0015] In this application, a buffer is provided between the edge pad and the edge of the solar cell along a first direction, and the buffer is located between the solder strip and at least one side of the solar cell along a second direction. During the lamination process of the solar cell, the buffer plays a buffering and protective role between the solder strip and the solar cell, thereby dispersing the stress between the solar cells, reducing the risk of microcracks in the solar cells, and improving the service life of the photovoltaic module.

[0016] Furthermore, since the solder ribbon extends from the front of one solar cell to the back of another, or from the back of one solar cell to the front of another, and there is a buffer between the solder ribbon and at least one solar cell, the connection reliability between the solder ribbon and the solar cell is improved. It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the photovoltaic module provided in this application in a specific embodiment; Figure 2 for Figure 1 A schematic diagram of a connection structure for solar cells in a battery cell; Figure 3 for Figure 1A schematic diagram of another connection structure for the battery cells in the diagram; Figure 4 A schematic diagram of a solar cell with a main grid. Figure 5 for Figure 4 A partial structural diagram; Figure 6 A schematic diagram of a solar cell without a main grid. Figure 7 for Figure 6 A partial structural diagram; Figure 8 This is a partial structural diagram of a battery cell in one embodiment; Figure 9 This is a partial structural diagram of the battery cell in another embodiment; Figure 10 This is a partial structural diagram of the battery cell in another embodiment; Figure 11 This is a partial structural diagram of the battery cell in another embodiment; Figure 12 This is a partial structural diagram of the battery cell in another embodiment; Figure 13 This is a partial structural diagram of the battery cell in another embodiment.

[0018] Explanation of reference numerals in the attached figures: 101 - Front-side package structure; 102 - Frontal film layer; 201 - Backside packaging structure; 202 - Backside film layer; 1- Battery cells; 11-Pad; 111 - Edge pad; 12-Channel; 121 - Bus gap; 13-Fine grid; 131 - First fine grid; 132 - Second fine grid; 14-Main gate; 2- Welding strip; 3- Buffer components.

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. Detailed Implementation

[0020] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0021] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0022] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0024] This application provides a photovoltaic module, such as... Figures 1-3 As shown, a photovoltaic module includes solar cells 1, solder ribbons 2, and buffer components 3. The solder ribbons 2 connect adjacent solar cells 1 to form a cell string. Figure 4 and Figure 5 As shown, the solar cell 1 has multiple pads 11 distributed along a first direction X, including an outermost edge pad 111 located in the first direction X. Adjacent solar cells 1 are connected by solder ribbons 2, which are connected to the pads 11. The pads 11 provide ample connection points for the solder ribbons 2, allowing current in the solar cell 1 to flow through the pads 11 to the solder ribbons 2, thereby extracting current from the solar cell 1 and achieving electrical connection between the solar cells 1.

[0025] Specifically, multiple solar cells 1 are arranged along a first direction X, and the projections of two adjacent solar cells 1 along a second direction Y overlap, where the second direction Y is the thickness direction of the solar cell 1. By partially overlapping adjacent solar cells 1, the space utilization rate of the photovoltaic module can be improved, thereby increasing the energy density or packaging density of the photovoltaic module. However, during the lamination process of the photovoltaic module, there is a problem that the increased stress between the solar cells 1 can easily lead to microcracks.

[0026] To address this technical issue, the photovoltaic module also includes a buffer 3. Along the first direction X, the buffer 3 is located between the edge pad 111 and the edge of the cell 1; along the second direction Y, the buffer 3 is located between the solder strip 2 and at least one side of the cell 1. The buffer 3 can reduce the stress between the solder strip 2 and the cell 1 during lamination, thereby protecting the cell 1, reducing the probability of microcracks in the cell 1, lowering the risk of damage to the photovoltaic module, and extending the service life of the photovoltaic module.

[0027] like Figure 2 As shown, in one embodiment, the buffer 3 is located between the solder strip 2 and one of the solar cells 1, providing a buffering effect for the solar cells 1 while reducing the amount of buffer 3 used, thus reducing the production cost of the photovoltaic module and the thickness of the cell string; as Figure 3 As shown, in another embodiment, the buffer element 3 is located between the solder strip 2 and the two solar cells 1, which improves the buffering effect of the buffer element 3 on the pressure between the solar cells 1. This application does not limit the specific distribution of the buffer element 3. In some embodiments, the projection of the buffer element 3 along the second direction Y is located in the overlapping area, so that the buffer element 3 is not visible when observing the manufactured photovoltaic module, thereby improving the simplicity and aesthetics of the photovoltaic module.

[0028] Furthermore, the buffer 3 can be made of adhesive (e.g., silicone sealant). Firstly, the adhesive is elastic, providing good cushioning for the solar cell 1. Secondly, the adhesive is viscous; placing the buffer 3 between the solder ribbon 2 and the solar cell 1 can fix the solder ribbon 2, thereby improving the reliability of the connection between the solder ribbon 2 and the solar cell 1. Thirdly, the adhesive is small in size, making it easy to place in the overlapping area and helping to reduce the production cost of the photovoltaic module. This application does not limit the specific material of the buffer 3.

[0029] Furthermore, the buffer element 3 is made of thermosetting adhesive. Using thermosetting adhesive for the buffer element 3 offers better curing properties compared to photocuring adhesives, thus reducing the risk of poor curing due to insufficient sunlight exposure. Simultaneously, the thermosetting adhesive buffer element 3 exhibits better high-temperature resistance and thermal stability, extending the lifespan of the photovoltaic modules.

[0030] In addition, the buffer 3 is a transparent adhesive, which means that the buffer 3 has high light transmittance and weak light energy absorption, so it will not affect the photoelectric conversion efficiency of the photovoltaic module and ensure the power of the photovoltaic module.

[0031] In some embodiments, the curing reaction temperature of the buffer 3 is equal to or lower than the welding temperature of the solder strip 2 and the solder pad 11.

[0032] In this embodiment, when the curing reaction temperature of the buffer 3 is equal to or lower than the welding temperature of the solder ribbon 2 and the solder pad 11, the buffer 3 can be cured when the solder ribbon 2 and the solder pad 11 are welded, thereby reducing the number of processes required to produce photovoltaic modules, improving the production efficiency of photovoltaic modules, and saving the production time of photovoltaic modules.

[0033] like Figure 1 As shown, the photovoltaic module also includes: a front encapsulation structure 101, a front film layer 102, a back film layer 202, and a back encapsulation structure 201. The front encapsulation structure 101, the front film layer 102, the back film layer 202, and the back encapsulation structure 201 encapsulate the cell string to ensure that the photovoltaic module has high mechanical strength, reduce the impact of hail, wind, mechanical vibration, etc. on the photovoltaic module, improve the sealing performance of the photovoltaic module, and enhance its corrosion resistance and safety.

[0034] Specifically, the front encapsulation structure 101 and the back encapsulation structure 201 can be one of rigid materials such as tempered glass, polyethylene terephthalate (PET), and polycarbonate (PC), or one of flexible materials such as polyvinyl fluoride (PVF), ethylene-tetrafluoroethylene copolymer (ETFE), and polyvinylidene fluoride (PVDF). These materials have high light transmittance, which can improve the photoelectric conversion efficiency of the photovoltaic module and ensure the power output of the photovoltaic module.

[0035] The front film layer 102 and the back film layer 202 can be one of the following materials: ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), polyvinyl butyral (PVB), EVA-POE-EVA co-extruded film (EPE), EVA-POE co-extruded film (EP).

[0036] The electrodes on the solar cell 1 are grid lines, which include positive grid lines and negative grid lines. For solar cells 1 with positive grid lines and negative grid lines located on the front and back sides respectively, such as emitter-back passivated cells (PERC), tunnel oxide-passivated contact cells (TOPCON), heterojunction cells with intrinsic thin-layer (HIT), and perovskite solar cells (PSC), the solder ribbon 2 extends from the front side of one solar cell 1 to the back side of another solar cell 1 or from the back side of one solar cell 1 to the front side of another solar cell 1 to achieve the connection of adjacent solar cells 1.

[0037] For PERC cells, along their thickness direction, the PERC cell sequentially includes a front surface silver electrode, a front surface silicon nitride passivation layer, a phosphorus emitter layer, a P-type substrate silicon layer, a local aluminum back field, a metallic aluminum back electrode, and a back passivation layer (Al2O3 / SiN). x PERC cells use a passivation film to passivate the back surface, replacing the all-aluminum back surface, which enhances light reflection on the silicon substrate and reduces the recombination rate on the back surface, thus improving the photoelectric conversion efficiency of the cell by 0.5%-1%.

[0038] For a TOPCon cell, along its thickness direction, it sequentially comprises a silver electrode, a front-surface silicon nitride passivation layer, a boron-doped emitter, an N-type substrate silicon layer, a diffused doped layer, an ultrathin silicon oxide layer, doped polycrystalline silicon, silicon nitride, and the silver electrode. The back of the cell consists of an ultrathin silicon oxide layer (1nm~2nm) and a phosphorus-doped microcrystalline amorphous mixed Si film, which together form a passivation contact structure. This structure blocks minority carrier recombination, increasing the cell's open-circuit voltage and short-circuit current. The ultrathin oxide layer allows majority carrier electrons to tunnel into the polycrystalline silicon layer while simultaneously blocking minority carrier recombination. The excellent passivation effect of the ultrathin silicon oxide and heavily doped silicon film causes band bending on the silicon wafer surface, creating a field passivation effect. This significantly increases the probability of electron tunneling, reduces contact resistance, and improves the cell's open-circuit voltage and short-circuit current, thereby enhancing the cell's photoelectric conversion efficiency.

[0039] For HIT cells, along their thickness direction, HIT cells sequentially include a front low-temperature silver electrode, a front conductive film, an N-type amorphous silicon film, an intrinsic amorphous silicon film, an N-type substrate silicon layer, an intrinsic amorphous silicon film, a P-type amorphous silicon film, a back conductive film, and a back low-temperature silver electrode.

[0040] For a perovskite solar cell, along its thickness direction, the perovskite solar cell sequentially includes a substrate material, a conductive thin film, an electron transport layer (titanium dioxide), a perovskite absorption layer (hole transport layer), and a metal cathode. Perovskite materials have a high light absorption coefficient and a long carrier diffusion distance. After the photons absorbed by the perovskite material are converted into electrons, they are easily collected by the electrodes with minimal loss, thus generating high photogenerated voltage and current, resulting in high photoelectric conversion efficiency.

[0041] In one embodiment, such as Figure 4 and Figure 5 The solar cell 1 has a main grid 14 extending along a first direction X and fine grids 13 extending along a third direction Z, i.e., a main grid cell. For example, multiple fine grids 13 are spaced apart along the first direction X, and multiple main grids 14 are spaced apart along the third direction Z. Each main grid 14 is connected to multiple fine grids 13. The photocurrent generated by the solar cell 1 can be collected by the fine grids 13, and the photocurrent collected by the fine grids 13 can be collected by the main grids 14. A pad 11 is provided on the main grid 14, and a solder ribbon 2 is soldered to the pad 11 to connect the solder ribbon 2 to the main grid 14. The photocurrent in the main grid 14 can flow through the pad 11 to the solder ribbon 2, thereby extracting current from the solar cell 1.

[0042] In another embodiment, such as Figure 6 and Figure 7 As shown, the solar cell 1 only has fine grids 13 extending along the third direction Z, without a main grid 14, i.e., a gridless solar cell. A gridless solar cell can reduce the amount of paste used for printed electrodes, reducing the production cost of the solar cell 1. At the same time, it reduces the shading of the main grid 14 on the surface of the solar cell 1, which is beneficial to improving the photoelectric conversion efficiency of the solar cell 1.

[0043] In other embodiments, the specific structure of the battery cell 1 can also be configured as a structure with spaced main grids 14. This application does not limit the specific structure of the battery cell 1.

[0044] In some embodiments, such as Figure 5 or Figure 7 As shown, along the first direction X, a busbar 12 is provided on at least one side of the battery cell 1, and the busbar 12 is located between the edge pad 111 and the edge of the battery cell 1. Along the first direction X, a buffer member 3 is located between the busbar 12 and the edge of the battery cell 1.

[0045] The busbar 12 can be configured as a harpoon structure. This harpoon-structured busbar 12 collects the current gathered by the fine grid 13 located at the edge of the solar cell 1, ensuring the photovoltaic module's photoelectric conversion efficiency. The harpoon-structured busbar 12 is connected to the edge pad 111. Along the first direction X, there is sufficient space between the busbar 12 and the edge of the solar cell 1 to accommodate the buffer 3, reducing the probability of incorrect placement of the buffer 3. Simultaneously, the busbar 12 is easy to position, improving the accuracy of the buffer 3's placement.

[0046] In other embodiments, the busbar 12 may also be configured as a U-shaped, V-shaped, semi-circular, semi-elliptical or other semi-enclosed structure. This application does not limit the specific structure of the busbar 12.

[0047] Combination Figures 8 to 13 As shown, the specific configuration of buffer 3 in different embodiments will be described below by way of example.

[0048] In some embodiments, such as Figure 8 and Figure 9 As shown, the manifold 12 has a manifold gap 121, and at least a portion of the buffer 3 is located within the manifold gap 121.

[0049] In this embodiment, the bus gap 121 provides sufficient space for the buffer 3 to be arranged, so that the buffer 3 can improve the connection strength between the battery cells 1 without affecting the photoelectric conversion efficiency of the battery cells 1.

[0050] Specifically, the fine grid 13 includes a first fine grid 131 and a second fine grid 132 that are in contact with the busbar 12. The first fine grid 131 penetrates the busbar gap 121, while the second fine grid 132 does not penetrate the busbar gap 121.

[0051] Optionally, the fine grid 13 in contact with the busbar 12 has both a first fine grid 131 and a second fine grid 132.

[0052] like Figure 8 As shown, the outermost fine grid 13 is the second fine grid 132, and the buffer 3 is located between the outermost first fine grid 131 and the edge of the battery cell 1. At this time, the distance between the outermost first fine grid 131 and the edge of the battery cell 1 is relatively large, which facilitates the installation of the buffer 3, and allows for the installation of a relatively large buffer 3 to ensure the buffering effect of the buffer 3 between the solder strip 2 and the battery cell 1.

[0053] like Figure 9As shown, the outermost fine grid 13 is the first fine grid 131, and the buffer 3 is located on the side of the outermost first fine grid 131 away from the edge of the solar cell 1. A second fine grid 132 is located between the outermost first fine grid 131 and the edge pad 111, providing a larger space within the busbar gap 121 to accommodate the buffer 3. The outermost first fine grid 131 is connected to the busbar 12, allowing the photocurrent collected by the outermost first fine grid 131 to flow through the busbar 12 to the edge pad 111 and then be discharged, even if the outermost first fine grid 131 does not contact the solder strip 2.

[0054] Optionally, the fine gate 13 in contact with the busbar 12 may only have a second fine gate 132.

[0055] like Figure 10 As shown, the range of the buffer 3 can be set at this time, the position restriction when setting the buffer 3 is small, and the size of the buffer 3 can be set to be large, so as to improve the buffering effect of the buffer 3 between the solder strip 2 and the battery cell 1.

[0056] Optionally, only the first fine grid 131 is in contact with the fine grid 13 of the current collector 12. In this case, the fine grid 13 at the edge of the cell 1 has a stronger ability to collect photocurrent, and the photovoltaic module has a higher photoelectric conversion efficiency.

[0057] In this application, when the buffer 3 avoids the fine grid 13, the thickness of the stacked cells 1 is reduced, thereby improving the buffering stress effect of the buffer 3. This application does not limit the specific location of the buffer 3.

[0058] In some embodiments, such as Figure 11 As shown, the buffer 3 is located between the outermost fine grid 13 and the edge of the battery cell 1.

[0059] In this embodiment, regardless of whether the fine grids 13 in contact with the current collector 12 are all first fine grids 131, all second fine grids 132, or a combination of first fine grids 131 and second fine grids 132, the buffer 3 is disposed between the outermost fine grid 13 and the edge of the solar cell 1. In this case, there is no need to differentiate the placement of the buffer 3 based on the type of fine grids 13 in contact with the current collector 12, thus reducing the complexity of setting up the buffer 3. Simultaneously, the buffer 3 will not obstruct the fine grids 13, which is beneficial for improving the photoelectric conversion efficiency of the solar cell 1.

[0060] In the above embodiments, the buffer 3 can be made of insulating material. Since the buffer 3 does not contact the fine grid 13, the buffer 3 will not cause the fine grid 13 to break during the lamination process, thus affecting the photoelectric conversion efficiency of the photovoltaic module.

[0061] In the above embodiments, the buffer 3 can also be made of a conductive material. When the buffer 3 is made of a conductive material, such as... Figure 12 and Figure 13The buffer 3 can come into contact with the fine grid 13 and cause the fine grid 13 to break during the lamination process, thus affecting the photoelectric conversion efficiency of the photovoltaic module.

[0062] Continue to refer to Figures 8 to 13 The shape of the buffer 3 can be circular. In other embodiments, the shape of the buffer 3 can also be elliptical, square, rectangular, triangular or other shapes. This application does not limit the specific shape of the buffer 3.

[0063] The distribution of the buffer element 3 on the battery cell 1 can be either continuous and uniform, or intermittent. For example, Figure 4 For example, in one embodiment, along the third direction Z, the buffer 3 can be uniformly and continuously arranged on the solar cell 1. This design results in a higher connection strength between the solar cell 1 and the solder ribbon 2, improving the reliability of the connection between the solar cells 1. In another embodiment, along the third direction Z, the buffer 3 can be correspondingly arranged at the odd-numbered columns of the main grid 14 of the solar cell 1, while not correspondingly arranged at the even-numbered columns. This design, while ensuring the connection strength between the solar cell 1 and the solder ribbon 2, reduces the amount of buffer 3 used, lowering the manufacturing cost of the photovoltaic module. In yet another embodiment, along the third direction Z, the buffer 3 can be correspondingly arranged at the first two columns of the main grid 14 of the solar cell 1, while not correspondingly arranged at the third column. The three columns of main grid 14 are arranged in groups and alternately. This design further improves the connection strength between the solar cell 1 and the solder ribbon 2 while reducing the amount of buffer 3 used, lowering the manufacturing cost of the photovoltaic module. This application does not limit the specific distribution and quantity on the solar cell 1.

[0064] like Figure 2 or Figure 3 As shown, along the second direction Y, the thickness H of the buffer 3 satisfies: 100μm≤H≤200μm. For example, the thickness H of the buffer 3 can be: 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm, etc.

[0065] The thickness H of the buffer 3 should not be too large or too small. If the thickness H of the buffer 3 is too large (e.g., greater than 200 μm), the stacking thickness between two adjacent solar cells 1 will be too large, increasing the manufacturing cost of the buffer 3. It will also easily cause uneven stress between the solder ribbon 2 and the solar cell 1 and / or between solar cells 1, increasing the risk of solar cell 1 cracking or microcracks during the lamination process of the photovoltaic module. At the same time, it will increase the volume of the photovoltaic module, which is not conducive to the transportation and installation of the photovoltaic module. If the thickness H of the buffer 3 is too small (e.g., less than 100 μm), the buffer 3 set between the solder ribbon 2 and the solar cell 1 can provide a weak buffering effect, and there is a possibility that it cannot effectively prevent the solder ribbon 2 from putting too much pressure on the solar cell 1 during the lamination process, which may cause microcracks in the solar cell 1.

[0066] Therefore, the thickness H of the buffer 3 should be selected within a suitable range. That is, when the thickness H of the buffer 3 satisfies 100μm≤H≤200μm, it can protect the solder ribbon 2 and the cell 1 during the lamination process of the photovoltaic module, reduce the risk of stress concentration, reduce the risk of cell 1 cracking or microcracks, and at the same time reduce the manufacturing cost of the buffer 3 and reduce the thickness of the photovoltaic module.

[0067] like Figure 5 or Figure 7 As shown, along the perpendicular second direction Y, the dimension d of the buffer 3 satisfies: 0.5mm ≤ d ≤ 1.5mm. For example, the dimension d of the buffer 3 can be: 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, etc.

[0068] The size d of the buffer 3 should not be too large or too small. If the size d of the buffer 3 is too large (e.g., greater than 1.5 mm), the buffer 3 will overflow the busbar gap 121 or the edge of the cell 1, blocking the fine grid 13 and affecting the photoelectric conversion efficiency of the photovoltaic module. Overflowing the edge of the cell 1 will cause waste of the buffer 3 and affect other components of the photovoltaic module. At the same time, it will increase the volume of the photovoltaic module, which is not conducive to the transportation and installation of the photovoltaic module. If the size d of the buffer 3 is too small (e.g., less than 0.5 mm), the buffer 3 set between the solder ribbon 2 and the cell 1 can provide a weak buffering effect. There is a possibility that it cannot effectively prevent the solder ribbon 2 from putting too much pressure on the cell 1 during the lamination process, which may cause microcracks in the cell 1.

[0069] Therefore, the size d of the buffer 3 should be selected within a suitable range. That is, when the thickness H of the buffer 3 satisfies 0.5mm≤d≤1.5mm, it can protect the solder strip 2 and the cell 1 during the lamination process of the photovoltaic module, reduce the risk of stress concentration, reduce the risk of cell 1 cracking or microcracks, and at the same time reduce the manufacturing cost of the buffer 3 and reduce the thickness of the photovoltaic module.

[0070] The above descriptions are merely specific implementations of the embodiments of this application, but the protection scope of the embodiments of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the embodiments of this application should be covered within the protection scope of the embodiments of this application. Therefore, the protection scope of the embodiments of this application should be determined by the protection scope of the claims.

Claims

1. A photovoltaic module, characterized in that, The photovoltaic module includes: A battery cell (1), a plurality of said battery cells (1) are arranged along a first direction (X), and the projections of two adjacent said battery cells (1) along a second direction (Y) have an overlapping area, said battery cell (1) has a plurality of pads (11) distributed along the first direction (X), said pads (11) including the outermost edge pads (111) in the first direction (X). The solder strip (2) connects two adjacent battery cells (1) and the solder strip (2) is connected to the solder pad (11); The buffer (3) is located between the edge pad (111) and the edge of the cell (1) along the first direction (X), and between the solder strip (2) and the cell (1) on at least one side thereon along the second direction (Y).

2. The photovoltaic module according to claim 1, characterized in that, Along the first direction (X), at least one side of the battery cell (1) is provided with a busbar (12), the busbar (12) being located between the edge pad (111) and the edge of the battery cell (1); Along the first direction (X), the buffer (3) is located between the busbar (12) and the edge of the battery cell (1).

3. The photovoltaic module according to claim 2, characterized in that, The battery cell (1) is provided with a fine grid (13) extending along a third direction (Z), and the buffer (3) is located between the outermost fine grid (13) and the edge of the battery cell (1).

4. The photovoltaic module according to claim 2, characterized in that, The confluence section (12) has a confluence gap (121), and at least a portion of the buffer (3) is located within the confluence gap (121).

5. The photovoltaic module according to claim 4, characterized in that, The battery cell (1) is provided with a fine grid (13) extending in a third direction (Z). The fine grid (13) includes a first fine grid (131) and a second fine grid (132) that are in contact with the busbar (12). The first fine grid (131) penetrates the busbar gap (121), and the second fine grid (132) does not penetrate the busbar gap (121). The outermost fine grid (13) is the second fine grid (132), and the buffer (3) is located between the outermost first fine grid (131) and the edge of the battery cell (1); Alternatively, the outermost fine grid (13) is the first fine grid (131), and the buffer (3) is located on the side of the outermost first fine grid (131) away from the edge of the battery cell (1).

6. The photovoltaic module according to any one of claims 1-5, characterized in that, The projection of the buffer (3) along the second direction (Y) lies within the overlapping area.

7. The photovoltaic module according to any one of claims 1-5, characterized in that, The buffer (3) is a thermosetting adhesive.

8. The photovoltaic module according to claim 7, characterized in that, The curing reaction temperature of the buffer (3) is equal to or lower than the welding temperature of the solder strip (2) and the solder pad (11).

9. The photovoltaic module according to any one of claims 1-5, characterized in that, Along the second direction (Y), the thickness H of the buffer (3) satisfies: 100μm≤H≤200μm.

10. The photovoltaic module according to any one of claims 1-5, characterized in that, Along the second direction (Y), the size d of the buffer (3) satisfies: 0.5mm≤d≤1.5mm.

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