Back contact type photovoltaic module

Abstract

The invention discloses a back contact type photovoltaic module, and belongs to the technical field of photovoltaic modules. The back contact type photovoltaic module comprises a battery piece, a first surface of the battery piece is provided with a plurality of first fine grids and a plurality of second fine grids which extend along a first direction and are alternately arranged at intervals along a second direction, and the first surface of the battery piece is also provided with a first suspension main grid extending along the second direction; the first suspension main grid is connected to the plurality of first fine grids, at least one second insulating block is arranged between the first suspension main grid and each second fine grid, and the first direction intersects with the second direction; and the first electric connecting piece extends along the second direction and is connected to the first suspension main grid, a bonding layer is arranged between the first electric connecting piece and the first suspension main grid, and the thickness h of the bonding layer is greater than or equal to 15 microns and less than or equal to 70 microns.

Description

Technical Field

[0001] The present application relates to the technical field of photovoltaic modules, and in particular to a back-contact photovoltaic module. Background Art

[0002] Back-contact photovoltaic modules, a type of photovoltaic module, have a plurality of first and second filaments extending in a first direction and alternating in a second direction on the back side of the solar cell. These filaments collect the current generated by the solar cell. A first busbar and a second busbar extending in the second direction are also provided on the back side of the solar cell. The first busbar is connected to the plurality of first filaments, and the second busbar is connected to the plurality of second filaments. This allows the current collected by the first and second busbars to be aggregated. An electrical connector extends in the second direction and is connected to either the first or second busbar to aggregate the current collected by the first or second busbar and transmit it to an external circuit.

[0003] In related technologies, in order to improve the reliability of the connection between the electrical connector and the first main grid or the second main grid, a conductive adhesive layer can be set between the electrical connector and the first main grid or the second main grid to improve the reliability of the connection between the electrical connector and the first main grid or the second main grid through the conductive adhesive layer.

[0004] However, the main grid of the back-contact photovoltaic module needs to cross fine grids of different polarities, and for this purpose, an insulating block is required to electrically isolate the main grid from the fine grids of different polarities. The surface of the insulating block facing away from the battery body protrudes from the battery body, often forming a roughly arched structure, causing the surface of the main grid located on the insulating block to present an undulating structure. On the one hand, this undulating structure lengthens the carrier transmission path, which increases the recombination loss. On the other hand, the undulating structure is not conducive to forming an effective connection with the external interconnection bar, which easily leads to the problem of poor contact between the main grid and the interconnection bar. If the thickness of the conductive adhesive layer is too small, it is difficult for the conductive adhesive layer to form a metallized interconnection with the electrical connector, and it is also difficult to form a metallized interconnection with the first main grid or the second main grid, resulting in a local short circuit in the photovoltaic module, affecting the photoelectric conversion efficiency of the photovoltaic module. If the thickness of the conductive adhesive layer is too large, not only will the battery cell be prone to problems such as hidden cracks during the lamination process of the photovoltaic module, affecting the process yield of the photovoltaic module, but it will also make the carrier transmission path longer and the resistance greater, affecting the current collection efficiency. Summary of the Invention

[0005] The present application discloses a back-contact photovoltaic module to solve or at least partially solve the problems existing in the prior art, such as the conductive adhesive layer being too thin, making it difficult to form a metallized interconnection with the electrical connector or the main grid, resulting in a local short circuit in the photovoltaic module and affecting the photoelectric conversion efficiency of the photovoltaic module; or the conductive adhesive layer being too thick, not only causing problems such as hidden cracks in the cell during the lamination process of the photovoltaic module, affecting the yield rate of the photovoltaic module process, but also making the carrier transmission path longer and the electrons larger, affecting the current collection efficiency.

[0006] In order to solve the above technical problems, this application is implemented as follows:

[0007] The present application discloses a back-contact photovoltaic module, which includes a solar cell, wherein the first surface of the solar cell is provided with a plurality of first fine grids and a plurality of second fine grids extending along a first direction and arranged alternately at intervals along a second direction, and the first surface of the solar cell is further provided with a first floating main grid extending along the second direction, the first floating main grid being connected to the plurality of first fine grids, at least one second insulating block being provided between the first floating main grid and each of the second fine grids, and the second direction intersecting with the first direction; a first electrical connector, the first electrical connector extending along the second direction and connected to the first floating main grid, a bonding layer being provided between the first electrical connector and the first floating main grid, the thickness of the bonding layer being h, and satisfying 15μm≤h≤70μm.

[0008] Optionally, the second insulating blocks include a plurality of second insulating blocks, which are spaced apart along the second direction, and a first gap is provided between two adjacent second insulating blocks; along the second direction, the bonding layer includes a first sub-bonding layer provided at a position corresponding to the first gap and a second sub-bonding layer provided above the second fine gate; the thickness of the first sub-bonding layer is h1, and the thickness of the second sub-bonding layer is h2, satisfying 1≤h1 / h2≤4.

[0009] Optionally, 30 μm≤h1≤70 μm; and / or 15 μm≤h2≤50 μm are satisfied.

[0010] Optionally, the second insulating blocks include a plurality of second insulating blocks, which are spaced apart along the second direction, with a first gap between two adjacent second insulating blocks; along the second direction, the first suspended main grid includes a first sub-suspended main grid arranged at a position corresponding to the first gap and a second sub-suspended main grid arranged above the second fine grid; the thickness of the first sub-suspended main grid is L1, and the thickness of the second sub-suspended main grid is L2, satisfying 1.5≤L1 / L2≤5.

[0011] Optionally, L1 ≥ 20 μm; and / or 5 μm ≤ L2 ≤ 30 μm.

[0012] Optionally, the second insulating blocks include a plurality of second insulating blocks, which are spaced apart along the second direction, and a first gap is provided between two adjacent second insulating blocks; along the second direction, the first suspended main grid includes a first sub-suspended main grid provided at a position corresponding to the first gap and a third sub-suspended main grid provided above the second insulating block; the thickness of the first sub-suspended main grid is L1, and the thickness of the third sub-suspended main grid is L3, satisfying L1>L3.

[0013] Optionally, the thickness of the second insulating block is k1, the thickness of the first fine grid or the second fine grid is m1, and 1.5≤k1 / m1≤6 is satisfied.

[0014] Optionally, 15 μm≤k1≤50 μm is satisfied; and / or, along the second direction, the width of the second insulating block is k2, which satisfies 400 μm≤k2≤800 μm.

[0015] Optionally, 5 μm≤m1≤30 μm is satisfied; and / or, along the second direction, the width of the first fine grid or the second fine grid is m2, which satisfies 10 μm≤m2≤150 μm.

[0016] Optionally, along the thickness direction of the photovoltaic module, a difference between the highest point of the second insulating block and the lowest point of the first sub-suspended busbar is within 10 μm.

[0017] Optionally, along the thickness direction of the photovoltaic module, the distance d between the first electrical connector and the solar cell satisfies 70 μm≤d≤150 μm.

[0018] Optionally, the first floating main grid includes first connection points spaced apart along the second direction and a first connection main grid connected between two adjacent first connection points; the bonding layer is provided between the first connection points and the first electrical connector.

[0019] Optionally, along the first direction, the width of the bonding layer is greater than or equal to 0.8 times the width of the first electrical connector, and less than or equal to the width of the first connection point.

[0020] The present application discloses a back-contact photovoltaic module, which includes a solar cell, wherein the first surface of the solar cell is provided with a plurality of first fine grids and a plurality of second fine grids extending along a first direction and arranged alternately at intervals along a second direction, and the first surface of the solar cell is further provided with a first floating main grid extending along the second direction, the first floating main grid being connected to the plurality of first fine grids, at least one second insulating block being provided between the first floating main grid and each of the second fine grids, and the first direction intersecting with the second direction; a first electrical connector, the first electrical connector extending along the second direction and connected to the first floating main grid, a bonding layer being provided between the first electrical connector and the first floating main grid, the thickness of the bonding layer being h, and satisfying 15μm≤h≤70μm.

[0021] In the present application, a bonding layer is provided between the first electrical connector and the first floating main grid, and the thickness of the bonding layer is greater than or equal to 15 μm and less than or equal to 70 μm. In a back-contact photovoltaic module, the first floating main grid needs to span multiple first fine grids and multiple second fine grids, and a second insulating block needs to be provided between each second fine grid and the first floating main grid to block the second fine grid and the first floating main grid. To prevent the second fine grid from piercing the second insulating block, causing the second fine grid to connect to the first floating main grid and causing a local short circuit in the photovoltaic module, the second insulating block is often provided to be relatively thick to ensure the effect of electrical isolation. Therefore, the second insulating block will protrude from the surface of the battery cell body away from the battery cell body, forming a roughly arched structure, so that the first floating main grid located above the second insulating block is supported to a certain height, and the entire surface of the first floating main grid presents an undulating structure, that is, a floating main grid structure. The undulating structure of the suspended busbar lengthens the carrier transmission path, increasing recombination losses. Furthermore, the undulating structure hinders effective connection between the busbar and external electrical connectors, easily leading to poor contact between the busbar and the connectors. By providing a bonding layer between the first electrical connector and the first suspended busbar, the metallized interconnections between the bonding layer and the first electrical connector, as well as between the bonding layer and the first suspended busbar, are more reliable, improving the bonding strength between the bonding layer and the first electrical connector, and between the bonding layer and the first suspended busbar, thereby ensuring the photovoltaic module's photoelectric conversion efficiency and the module's manufacturing yield. Furthermore, the provision of the bonding layer prevents the carrier transmission path from being excessively long, which can increase recombination losses.

[0022] Furthermore, the thickness of the bonding layer is greater than or equal to 15 μm, so that the metallization interconnection between the bonding layer and the first electrical connector and between the bonding layer and the first suspended main grid is more reliable, and the problem of poor contact caused by the first electrical connector and the first suspended main grid being detached due to too low tension is avoided. The thickness of the bonding layer is less than or equal to 70 μm, which can avoid the bonding layer being too thick, resulting in excessively high costs for photovoltaic modules. Moreover, if the bonding layer is too thick, problems such as hidden cracks may easily occur in the cell during the lamination of the photovoltaic module. In addition, if the bonding layer is too thick, the transmission path of the carriers is increased, resulting in recombination losses. Therefore, in the metallization interconnection based on the first suspended main grid with a second insulating block, the thickness of the bonding layer is greater than or equal to 15 μm and less than or equal to 70 μm, which helps to improve the reliability of the photovoltaic module and the process yield of the photovoltaic module and reduce the recombination losses of the carriers. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram showing the structure of the battery cell described in the embodiment of the present application;

[0024] Figure 2 Represents the cross section of the photovoltaic module described in the embodiment of this application Figure 1 ;

[0025] Figure 3 Represents the cross section of the photovoltaic module described in the embodiment of this application Figure 2 .

[0026] Reference numerals:

[0027] 10: Solar cell; 11: First fine grid; 12: Second fine grid; 13: First suspended main grid; 131: First sub-suspended main grid; 132: Second sub-suspended main grid; 133: Third sub-suspended main grid; 14: Second insulating block;

[0028] 20: first electrical connection member;

[0029] 30: bonding layer; 31: first sub-bonding layer; 32: second sub-bonding layer;

[0030] X: first direction; Y: second direction. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments derived by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of the present invention.

[0032] It should be understood that references throughout this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic associated with the embodiment is included in at least one embodiment of the present invention. Therefore, the appearances of "in one embodiment" or "in an embodiment" throughout this specification do not necessarily refer to the same embodiment. Furthermore, these particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0033] Reference Figure 1 , which shows a schematic structural diagram of the battery cell described in the embodiment of the present application; Figure 2 , showing the cross section of the photovoltaic module described in the embodiment of the present application Figure 1 ;reference Figure 3 , showing the cross section of the photovoltaic module described in the embodiment of the present application Figure 2 .

[0034] like Figures 1 to 3 As shown, an embodiment of the present application discloses a back-contact photovoltaic module, which includes a cell 10. The first surface of the cell 10 is provided with a plurality of first fine grids 11 and a plurality of second fine grids 12 extending along a first direction X and arranged alternately at intervals along a second direction Y. The first surface of the cell 10 is also provided with a first floating busbar 13 extending along the second direction Y. The first floating busbar 13 is connected to the plurality of first fine grids 11. A second insulating block 14 is provided between the first floating busbar 13 and each second fine grid 12. The first direction X intersects with the second direction Y; a first electrical connector 20, the first electrical connector 20 extending along the second direction Y and connected to the first floating busbar 13. A bonding layer 30 is provided between the first electrical connector 20 and the first floating busbar 13. The thickness of the bonding layer 30 is h, satisfying 15μm≤h≤70μm.

[0035] The embodiment of the present application discloses a back-contact photovoltaic module, which includes a cell 10. The cell 10 is the core component of the photovoltaic module and can convert solar energy into electrical energy. The cell 10 has a light-receiving surface facing the sunlight, also referred to as the front side, and the cell 10 also has a backlight surface facing away from the sunlight, also referred to as the back side. A back-contact photovoltaic module means that the positive and negative grid lines of the cell 10 are both arranged on the back side of the cell 10 to avoid the positive and negative grid lines blocking the front side of the cell 10, thereby improving the photoelectric conversion efficiency of the photovoltaic module.

[0036] The following description of the present application will be made by taking the back side of the battery cell 10 as the first surface of the battery cell 10 as an example.

[0037] like Figure 1As shown, a plurality of first fine grids 11 and a plurality of second fine grids 12 are provided on the first surface of the cell 10. The plurality of first fine grids 11 and the plurality of second fine grids 12 extend along a first direction X and are alternately arranged along a second direction Y. The first fine grids 11 and the second fine grids 12 have opposite polarities. The current generated by the cell 10 is collected by the plurality of first fine grids 11 and the plurality of second fine grids 12.

[0038] The first fine grid 11 and the second fine grid 12 may be silver grid lines, silver-copper alloy grid lines, or copper grid lines. In this embodiment of the present application, no specific limitation is made. In actual applications, technicians can select as needed.

[0039] like Figure 1 As shown, the first surface of the solar cell 10 is further provided with a first floating busbar 13 and a second floating busbar. Both the first floating busbar 13 and the second floating busbar extend along the second direction Y and are spaced apart along the first direction X. The first floating busbar 13 is connected to a plurality of first fine grids 11 to aggregate the current collected by the plurality of first fine grids 11. The second floating busbar is connected to a plurality of second fine grids 12 to aggregate the current collected by the plurality of second fine grids 12. At least one second insulating block 14 is provided between the first floating busbar 13 and each second fine grid 12, and at least one first insulating block is provided between the second floating busbar and each first fine grid 11. The second insulating block 14 isolates the first floating busbar 13 from the second fine grid 12, and the first insulating block isolates the second floating busbar from the first fine grid 11, thereby preventing short circuits in the photovoltaic module and affecting the photovoltaic module's photoelectric conversion efficiency.

[0040] It should be noted that in the embodiment of the present application, the second direction Y intersects the first direction X. Preferably, the second direction Y is perpendicular to the first direction X. For example, the first direction X may be the length direction of the battery cell 10, and the second direction Y may be the width direction of the battery cell 10. Alternatively, the first direction X may be the width direction of the battery cell 10, and the second direction Y may be the length direction of the battery cell 10.

[0041] It should be noted that at least one second insulating block 14 is disposed between the first floating busbar 13 and each second fine grid 12. Persons skilled in the art may adjust this according to actual needs. As long as the insulation effect is satisfactory, the number of second insulating blocks 14 between the first floating busbar 13 and each second fine grid 12 can be one or more, and there is no particular limitation on the number. In the embodiments of the present application, the embodiment of the present application is described using the example of one second insulating block 14 disposed between the first floating busbar 13 and each second fine grid 12.

[0042] like Figure 2 and Figure 3As shown, the back-contact photovoltaic module disclosed in this application further includes a first electrical connector 20 and a second electrical connector. The first electrical connector 20 and the second electrical connector both extend along the second direction Y and are spaced apart along the first direction X. The first electrical connector 20 is connected to the first floating busbar 13, and the second electrical connector is connected to the second floating busbar. The current collected by the first floating busbar 13 is collected by the first electrical connector 20, and the current collected by the second floating busbar is collected by the second electrical connector, and the current is transmitted to an external circuit.

[0043] In the embodiment of the present application, a bonding layer 30 is provided between the first electrical connector 20 and the first floating busbar 13, and the thickness of the bonding layer 30 is greater than or equal to 15 μm and less than or equal to 70 μm. Along the thickness direction of the photovoltaic module, the bonding layer 30 comprises two parts, one of which is a conductive adhesive layer, such as a conductive glue. The other part is a welding layer on the first electrical connector 20. In other words, the first electrical connector 20 includes a first electrical connector body and a welding layer attached to the surface of the first electrical connector body. The welding layer may be a tin layer, a nickel layer, or the like. During the welding process of the electrical connector and the first floating busbar, the welding layer attached to the surface of the first electrical connector body joins and dissolves with the conductive adhesive layer, forming a bonding layer. The provision of the bonding layer 30 makes the metallization interconnection between the bonding layer 30 and the first electrical connector 20 and between the bonding layer 30 and the first floating main grid 13 more reliable, improves the bonding force between the bonding layer 30 and the first electrical connector 20 and between the bonding layer 30 and the first floating main grid 13, and ensures the photoelectric conversion efficiency of the photovoltaic module and the process yield of the photovoltaic module.

[0044] It should be noted that in the embodiment of the present application, the thickness of the bonding layer 30 refers to a minimum thickness greater than or equal to 15 μm and a maximum thickness less than or equal to 70 μm along the thickness direction of the photovoltaic module. Furthermore, the thickness of the first floating busbar 13 and the bonding layer 30 above the second insulating block 14 gradually increases from the top surface of the second insulating block 14 toward both sides.

[0045] In the embodiment of this application, Figure 2 and Figure 3 As shown, the bonding layer 30 is substantially continuous along the extension direction of the first electrical connector 20 , and there may be some disconnected areas, but the disconnected areas account for less than 5% of the entire length of the bonding layer 30 .

[0046] Illustratively, the thickness of the bonding layer 30 may be set to 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, or the like.

[0047] Table 1. Thickness of the bonding layer and the average tensile force between the first electrical connector and the first floating main grid.

[0048] Bonding layer thickness / μm 10 15 25 35 45 70 80 Mean tensile force / N 0.8 1.1 1.3 1.5 1.7 2.0 2.5

[0049] In the embodiment of the present application, the average tensile force between the diameter of the first electrical connector 20 and the first floating busbar 13 is between 1N and 2N, meeting the welding requirements of back-contact photovoltaic modules. Therefore, the lower limit of the thickness of the bonding layer 30 is 15μm, and the average tensile force between the first electrical connector 20 and the first floating busbar 13 is 1.1N, which ensures good reliability of the back-contact photovoltaic module. If the average tensile force between the first electrical connector 20 and the first floating busbar 13 is greater than 2N, that is, the thickness of the bonding layer 30 is greater than 70μm, the bonding layer 30 will inevitably be too thick. While meeting the tensile reliability requirements of the first electrical connector 20 and the first floating busbar 13, combined with the inherent undulation of the first floating busbar 13, an excessively thick bonding layer 30 can easily cause problems such as hidden cracks in the cell 10 during the photovoltaic module lamination process, resulting in defective photovoltaic modules. Furthermore, an excessively thick bonding layer 30 increases the risk of warping and deformation of the first electrical connector 20, leading to poor photovoltaic module manufacturing and reduced photovoltaic module yield. Moreover, if the bonding layer 30 is too thick, the cost of the photovoltaic module will be higher, resulting in unnecessary waste.

[0050] Furthermore, the thickness of the bonding layer 30 is greater than or equal to 15 μm, so that the metallization interconnection between the bonding layer 30 and the first electrical connector 20 and between the bonding layer 30 and the first floating main grid 13 is more reliable, and the problem of the first electrical connector 20 and the first floating main grid 13 falling off due to too low tension is avoided. The thickness of the bonding layer 30 is less than or equal to 70 μm, which can avoid the bonding layer 30 being too thick, resulting in excessive cost of the photovoltaic module. In addition, if the bonding layer 30 is too thick, the cell 10 is prone to problems such as hidden cracks during the lamination of the photovoltaic module. In addition, if the bonding layer is too thick, the carrier transmission path is increased, resulting in recombination losses. Therefore, in the metallization interconnection based on the first floating main grid 13 with the second insulating block 14, the thickness of the bonding layer 30 is greater than or equal to 15 μm and less than or equal to 70 μm, which helps to improve the reliability of the photovoltaic module and the process yield of the photovoltaic module and reduce recombination losses.

[0051] It should be noted that the first electrical connector 20 and the second electrical connector in the embodiment of the present application can connect two adjacent battery cells 10 to form a battery string. Along the thickness direction of the photovoltaic module, the thickness of the first electrical connector 20 and the thickness of the second electrical connector are both greater than or equal to 150μm and less than or equal to 300μm. Exemplarily, the first electrical connector 20 and the second electrical connector can be welding strips, and the cross-section of the welding strip in the thickness direction of the photovoltaic module can be a circular structure, a rectangular structure, or other structures. The welding strip can include only a substrate, or the welding strip includes a substrate and a welding layer coated on the surface of the substrate. Among them, the substrate can be a copper substrate, an aluminum substrate, a silver substrate, a nickel substrate, etc. The welding layer can be a nickel layer, a tin layer, an aluminum layer, etc.

[0052] For example, along the thickness direction of the photovoltaic module, the thickness of the first electrical connector 20 and the thickness of the second electrical connector may be 150 μm, 180 μm, 200 μm, 220 μm, 250 μm, 280 μm, 300 μm, etc.

[0053] Alternatively, as Figures 1 to 3 As shown, the second insulating block 14 in the embodiment of the present application includes a plurality of second insulating blocks 14, and the plurality of second insulating blocks 14 are arranged at intervals along the second direction Y, and a first gap is provided between two adjacent second insulating blocks 14; along the second direction Y, the bonding layer 30 includes a first sub-bonding layer 31 arranged at a position corresponding to the first gap and a second sub-bonding layer 32 arranged above the second fine gate 12; the thickness of the first sub-bonding layer 31 is h1, and the thickness of the second sub-bonding layer 32 is h2, satisfying 1≤h1 / h2≤4.

[0054] like Figure 1 As shown, in this embodiment of the present application, multiple second insulating blocks 14 are provided. Each second insulating block 14 is positioned between a first floating busbar 13 and a second fine grid 12. This isolates the first floating busbar 13 from the second fine grid 12, preventing short circuits in the photovoltaic module. The multiple second insulating blocks 14 are spaced apart along the second direction Y, with a first gap between adjacent second insulating blocks 14. This first gap allows for the first fine grid 11 to be electrically connected to the first floating busbar 13, thereby collecting the current generated by the solar cell 10 through the first floating busbar 13.

[0055] like Figure 2 and Figure 3As shown, along the thickness direction of the photovoltaic module, the bonding layer 30 is arranged between the first floating main grid 13 and the first electrical connector 20. Along the second direction Y, the bonding layer 30 includes a first sub-bonding layer 31 arranged at a position corresponding to the first gap and a second sub-bonding layer 32 arranged above the second fine grid 12. The thickness of the first sub-bonding layer 31 is greater than the thickness of the second sub-bonding layer 32. The ratio of the thickness h1 of the first sub-bonding layer 31 to the thickness h2 of the second sub-bonding layer 32 is set to be greater than or equal to 1 and less than or equal to 4. The thicker first sub-bonding layer 31 can ensure the reliability of welding, and the thinner second sub-bonding layer 32 can prevent the second sub-bonding layer 32 from supporting the first electrical connector 20 too high, causing partial poor bonding. If the second sub-bonding layer 32 is too thin, it will lead to partial poor bonding. If the second sub-bonding layer 32 is too thick, it will lead to waste of bonding layer 30 material. Therefore, in the embodiment of the present application, the ratio of the thickness h1 of the first sub-bonding layer 31 to the thickness h2 of the second sub-bonding layer 32 is set to be greater than or equal to 1 and less than or equal to 4 to achieve a balance between material cost and bonding strength.

[0056] Furthermore, the first sub-bonding layer 31 is thicker to improve the reliability of the connection between the first fine grid 11 and the first floating main grid 13 through the first sub-bonding layer 31, reduce the risk of poor welding, and thus ensure the photoelectric conversion efficiency of the photovoltaic module.

[0057] Furthermore, the thinner thickness of the second sub-bonding layer 32 helps reduce the material usage of the bonding layer 30, thereby reducing the cost of the photovoltaic module. Furthermore, the thinner thickness of the second sub-bonding layer 32 can also prevent the second sub-bonding layer 32 from supporting the first electrical connector 20 too high, which could cause hidden cracks in the cell 10 during the photovoltaic module lamination process and affect the photovoltaic module manufacturing process yield.

[0058] For example, the ratio of the thickness h1 of the first sub-joining layer 31 to the thickness h2 of the second sub-joining layer 32 may be set to 1, 1.5, 2, 2.5, 3, 3.5, 4, or the like.

[0059] It should be noted that in the embodiment of the present application, the thickness h1 of the first sub-bonding layer 31 refers to the minimum thickness of the first sub-bonding layer 31 at the position corresponding to the first gap being greater than or equal to 30 μm, and the maximum thickness of the first sub-bonding layer 31 at the position corresponding to the first gap being less than or equal to 70 μm. The thickness h2 of the second sub-bonding layer 32 refers to the minimum thickness of the second sub-bonding layer 32 above the second fine grid 12 being greater than or equal to 15 μm, and the maximum thickness of the second sub-bonding layer 32 above the second fine grid 12 being less than or equal to 50 μm.

[0060] Optionally, 30 μm≤h1≤70 μm; and / or 15 μm≤h2≤50 μm are satisfied.

[0061] In the embodiment of the present application, the thickness h1 of the first sub-bonding layer 31 is set to be greater than or equal to 30 μm and less than or equal to 70 μm. This allows the first fine grid 11 and the first floating busbar 13 to be connected via the first sub-bonding layer 31, thereby improving the reliability of the connection between the first fine grid 11 and the first floating busbar 13. Furthermore, the first sub-bonding layer 31 can also support the first floating busbar 13, ensuring a more consistent height of the first floating busbar 13 and preventing the first floating busbar 13 from being positioned too low, which could lead to hidden cracks in the cells during the photovoltaic module lamination process and affect the photovoltaic module manufacturing process yield.

[0062] Exemplarily, the thickness h1 of the first sub-bonding layer 31 may be set to 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, or 70 μm.

[0063] In the embodiment of the present application, the thickness h2 of the second sub-bonding layer 32 is set to be greater than or equal to 15 μm and less than or equal to 50 μm, so that the thickness of the second sub-bonding layer 32 is thinner, the material consumption of the second sub-bonding layer 32 is reduced, and thus the cost of the photovoltaic module is reduced. Furthermore, the thin thickness of the second sub-bonding layer 32 can also prevent the second sub-bonding layer 32 from supporting the first electrical connector 20 too high, resulting in problems such as hidden cracks in the cell during the lamination of the photovoltaic module, affecting the process yield of the photovoltaic module. In addition, if the second sub-bonding layer 32 is set too thin, it will also cause poor bonding in some parts. If the second sub-bonding layer 32 is set too thick, the material of the bonding layer 30 is wasted, so the appropriate range can take into account the balance between bonding strength and material cost.

[0064] Exemplarily, the thickness h2 of the second sub-bonding layer 32 may be set to 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, or 50 μm.

[0065] As a preferred embodiment, 45 μm≤h1≤55 μm; and / or 15 μm≤h2≤30 μm are satisfied.

[0066] As a preferred embodiment, in this embodiment of the present application, the thickness h1 of the first sub-bonding layer 31 can be set to be greater than or equal to 45 μm and less than or equal to 55 μm. This further improves the reliability of the connection between the first fine grid 11 and the first floating busbar 13. Furthermore, the height consistency of the first floating busbar 13 is further improved, preventing hidden cracks in the solar cells during the photovoltaic module lamination process, which could affect the photovoltaic module manufacturing yield.

[0067] Illustratively, the thickness h1 of the first sub-bonding layer 31 may be set to 45 μm, 48 μm, 50 μm, 52 μm, 55 μm, or the like.

[0068] As a preferred embodiment, in the present embodiment, the thickness h2 of the second sub-bonding layer 32 can be set to be greater than or equal to 15 μm and less than or equal to 30 μm, thereby further reducing the thickness of the second sub-bonding layer 32 and thus further reducing the cost of the photovoltaic module. Furthermore, the smaller thickness of the second sub-bonding layer 32 can prevent the second sub-bonding layer 32 from supporting the first electrical connector 20 too high, which could lead to problems such as hidden cracks in the solar cells during the photovoltaic module lamination process, thereby affecting the photovoltaic module manufacturing process yield.

[0069] Illustratively, the thickness h2 of the second sub-bonding layer 32 may be set to 15 μm, 18 μm, 20 μm, 22 μm, 25 μm, 28 μm, 30 μm, or the like.

[0070] In another embodiment, the bonding layer 30 is continuous along the extension direction of the first electrical connector 20. Since the second insulating blocks 14 are arranged at intervals and form a roughly arched structure, the surface of the first floating busbar 13 also exhibits an undulating structure. Since the first electrical connector 20 is horizontal, the thickness of the bonding layer 30 between the first connector 20 and the first floating busbar 13 is not absolutely uniform. Since the second fine grid 12 and the first floating busbar 13 require electrical isolation from the insulating blocks 14, the first floating busbar 13 is located above the second fine grid 12 at the highest point of the undulation. Therefore, the thickness of the second sub-bonding layer 32 disposed above the second fine grid 12 must be minimal and must be greater than or equal to 15 μm. This ensures that the bonding layer 30 is continuously disposed along the extension direction of the first electrical connector, making the cell metallization interconnection more reliable. Furthermore, it prevents the tension at the highest point of the undulation of the first floating busbar 13 from being too low, which could cause the first electrical connector 20 to separate from the first floating busbar 13 and lead to poor contact.

[0071] Alternatively, as Figures 2 to 3 As shown, the second insulating block 14 in the embodiment of the present application includes a plurality of second insulating blocks 14, which are arranged at intervals along the second direction Y, and a first gap is formed between two adjacent second insulating blocks 14; along the second direction Y, the first floating main gate 13 includes a first sub-floating main gate 131 arranged at a position corresponding to the first gap and a second sub-floating main gate 132 arranged above the second fine gate 12; the thickness of the first sub-floating main gate 131 is L1, and the thickness of the second sub-floating main gate 132 is L2, satisfying 1.5≤L1 / L2≤5.

[0072] like Figure 2 and Figure 3As shown, along the second direction Y, the first floating busbar 13 includes a first sub-floating busbar 131 positioned at a position corresponding to the first gap and a second sub-floating busbar 132 positioned above the second fine grid 12. The thickness of the first sub-floating busbar 131 is set to L1, and the thickness of the second sub-floating busbar 132 is set to L2, satisfying 1.5≤L1 / L2≤5. In other words, the thickness of the first sub-floating busbar 131 is greater than the thickness of the second sub-floating busbar 132. A thicker first sub-floating busbar 131 ensures welding reliability, while a thinner second sub-floating busbar 132 enables electrical transmission between two adjacent first fine grids 11 along the extension direction of the bonding layer 30. However, an overly thin second sub-floating busbar 132 would hinder current transmission, while an overly thick second sub-floating busbar 132 would result in material waste. Therefore, the present application achieves a balance between material cost and electrical transmission effect by setting the ratio of the thickness of the first sub-floating busbar 131 to the thickness of the second sub-floating busbar 132 to be greater than or equal to 1.5 and less than or equal to 5, that is, 1.5≤L1 / L2≤5.

[0073] The thicker first sub-floating busbar 131 helps improve the reliability of the connection between it and the first fine grid 11, reducing the risk of poor welding and ensuring the photovoltaic module's photoelectric conversion efficiency. Furthermore, the thicker first sub-floating busbar 13 prevents the high height of some portions of the first sub-floating busbar 13 from causing hidden cracks in the cell 10 during the photovoltaic module lamination process, which could affect the module's manufacturing yield. Furthermore, while maintaining the same width, the thicker first sub-floating busbar 131 also increases its cross-sectional area, reducing its resistance.

[0074] In the embodiment of the present application, the second sub-floating busbar 132 is relatively thin. It serves only to connect two adjacent first sub-floating busbars 131 and does not connect to the second fine grid 12. A second insulating block 14 is disposed between the second sub-floating busbar 132 and the second fine grid 12. Therefore, the thinness of the second sub-floating busbar 132 helps reduce the material usage, thereby lowering the cost of the photovoltaic module. Furthermore, the relatively low thickness of the second sub-floating busbar 132 prevents excessive height of the second sub-floating busbar 132, which could lead to cracking in the solar cells 10 during the photovoltaic module lamination process and affect the photovoltaic module manufacturing yield. If the second sub-floating busbar 132 is too thin, it will hinder current transmission between the two adjacent first fine grids 11. On the other hand, if the second sub-floating busbar 132 is too thick, it wastes material for the connecting conductor and can easily cause cracking during lamination. Therefore, an appropriate range of thickness can achieve a good balance between current transmission and material cost.

[0075] For example, the ratio of the thickness L1 of the first sub-floating bus gate 131 to the thickness L2 of the second sub-floating bus gate 132 may be set to 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5.

[0076] Optionally, L1 ≥ 20 μm; and / or 5 μm ≤ L2 ≤ 30 μm.

[0077] In the embodiment of the present application, the thickness L1 of the first sub-floating busbar 131 is set to be greater than or equal to 20 μm. This makes the first sub-floating busbar 131 thicker, thereby improving the reliability of the connection between the first sub-floating busbar 131 and the first fine grid 11, ensuring the photovoltaic module's photoelectric conversion efficiency. Furthermore, this prevents the first floating busbar 13 from being too high in some locations, which could cause hidden cracks in the cell 10 during the photovoltaic module lamination process and affect the photovoltaic module's manufacturing yield.

[0078] For example, the thickness L1 of the first sub-floating bus gate 131 may be set to 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, etc.

[0079] In the embodiment of the present application, the thickness L2 of the second sub-floating busbar 132 is set to be greater than or equal to 5 μm and less than or equal to 30 μm. This allows for a thinner second sub-floating busbar 132, reducing the material usage and thus the cost of the photovoltaic module. Furthermore, the thinner thickness of the second sub-floating busbar 132 prevents excessive height of the second sub-floating busbar 132, which could lead to hidden cracks in the cell 10 during the photovoltaic module lamination process and affect the photovoltaic module manufacturing yield.

[0080] For example, the thickness L2 of the second sub-floating bus gate 132 may be set to 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, etc.

[0081] It should be noted that in the embodiment of the present application, the thickness L1 of the first sub-floating busbar 131 refers to the minimum thickness of the first sub-floating busbar 131 at the position corresponding to the first gap, which is greater than or equal to 20 μm. The thickness L2 of the second sub-floating busbar 132 refers to the minimum thickness of the second sub-floating busbar 132 above the second fine grid 12, which is greater than or equal to 5 μm, and the maximum thickness of the second sub-floating busbar 12 above the second fine grid 12, which is less than or equal to 30 μm.

[0082] Alternatively, as Figure 2 and Figure 3As shown, the second insulating block 14 in the embodiment of the present application includes a plurality of second insulating blocks 14, and the plurality of second insulating blocks 14 are arranged at intervals along the second direction Y, with a first gap between two adjacent second insulating blocks 14; along the second direction Y, the first floating main gate 13 includes a first sub-floating main gate 131 arranged at a position corresponding to the first gap and a third sub-floating main gate 133 arranged above the second insulating block 14; the thickness of the first sub-floating main gate 131 is L1, and the thickness of the third sub-floating main gate 133 is L3, satisfying L1>L3.

[0083] like Figure 2 and Figure 3 As shown, along the second direction Y, the first floating busbar 13 includes a first sub-floating busbar 131 disposed at a position corresponding to the first gap and a third sub-floating busbar 133 disposed above the second insulating block 14. The thickness of the first sub-floating busbar 131 is set to L1, and the thickness of the third sub-floating busbar 133 is set to L3, satisfying the relationship L1>L3. In other words, the thickness of the first sub-floating busbar 131 is greater than the thickness of the third sub-floating busbar 133.

[0084] In the embodiment of the present application, the thickness of the first sub-suspended busbar 131 is set to be greater than the thickness of the third sub-suspended busbar 133 so that the height of the side of the first suspended busbar 13 away from the solar cell 10 is more consistent. This avoids the problem of hidden cracks in the solar cell 10 due to the higher height of some parts of the first suspended busbar 13 during the lamination process of the photovoltaic module, thereby affecting the process yield of the photovoltaic module.

[0085] Furthermore, the relatively thick first sub-floating busbar 131 helps improve the reliability of the connection between it and the first fine grid 11, ensuring the photovoltaic module's photoelectric conversion efficiency. The relatively thin third sub-floating busbar 133 also helps reduce the material usage, thereby lowering the production cost of the photovoltaic module. Accordingly, the less thick third sub-floating busbar 133 reduces the surface roughness of the bonding layer 30, thereby reducing warping and deformation of the first electrical connector 20 after lamination.

[0086] It should be noted that, in the embodiment of the present application, the thickness L1 of the first sub-suspended main grid 131 is greater than the thickness L2 of the third sub-suspended main grid 133, which means that the minimum thickness of the first sub-suspended main grid 131 at the position corresponding to the first gap is greater than the maximum thickness of the third sub-suspended main grid 133 above the second insulating block 14.

[0087] Alternatively, as Figure 2 and Figure 3 As shown, in the embodiment of the present application, the thickness of the second insulating block 14 is k1, and the thickness of the first fine gate 11 or the second fine gate 12 is m1, satisfying 1.5≤k1 / m1≤6.

[0088] like Figure 2 and Figure 3 As shown, along the thickness direction of the photovoltaic module, the thickness of the second insulating block 14 is set to k1, and the thickness of the first fine grid 11 or the second fine grid 12 is set to m1, satisfying 1.5≤k1 / m1≤6. In other words, the thickness of the second insulating block 14 is greater than the thickness of the first fine grid 11 or the second fine grid 12.

[0089] In the embodiment of the present application, the ratio of the thickness k1 of the second insulating block 14 to the thickness m1 of the first fine grid 11 or the second fine grid 12 is set to be greater than or equal to 1.5 and less than or equal to 6. This allows the second insulating block 14 to block the first floating busbar 13 and the second fine grid 12, preventing the second fine grid 12 from piercing the second insulating block 14 due to the second insulating block 14 being too thin, thereby connecting the first floating busbar 13 to the second fine grid 12 and causing a local short circuit in the photovoltaic module, thereby affecting the photovoltaic module's photoelectric conversion efficiency.

[0090] Furthermore, this arrangement avoids the increased cost of the photovoltaic module due to the increased thickness of the second insulating block 14. Furthermore, a thick second insulating block 14 could easily lead to discontinuity in the first floating busbar 13, causing a local short circuit in the photovoltaic module and affecting the photovoltaic module's photoelectric conversion efficiency.

[0091] Furthermore, the thickness of the second insulating block 14 is relatively large, which easily leads to a gap between the first sub-bonding layer 31 and the first sub-suspended main grid 131 arranged corresponding to the first gap, making it difficult to form metallized interconnection, resulting in local short circuit in the photovoltaic module and affecting the photoelectric conversion efficiency of the photovoltaic module.

[0092] Optionally, 15 μm≤k1≤50 μm is satisfied; and / or, along the second direction Y, the width of the second insulating block 14 is k2, which satisfies 400 μm≤k2≤800 μm.

[0093] In the embodiment of the present application, the thickness k1 of the second insulating block 14 can be set to be greater than or equal to 15 μm and less than or equal to 50 μm along the thickness direction of the photovoltaic module. This configuration allows the second insulating block 14 to better block the first floating busbar 13 and the second fine grid 12, preventing the second fine grid 12 from piercing the second insulating block 14, causing the first floating busbar 13 to connect to the second fine grid 12, and thus causing a local short circuit in the photovoltaic module, thereby affecting the photovoltaic module's photoelectric conversion efficiency.

[0094] Furthermore, the above configuration can also avoid the increased thickness of the second insulating block 14, which could lead to higher photovoltaic module costs. Alternatively, it could lead to discontinuity in the first suspended busbar 13, causing a local short circuit in the photovoltaic module and impacting the photovoltaic module's photoelectric conversion efficiency. Alternatively, it could lead to a gap between the first sub-bonding layer 31 and the first sub-suspended busbar 131, which is located corresponding to the first gap, making it difficult to form a metallized interconnect, resulting in a local short circuit in the photovoltaic module and impacting the photovoltaic module's photoelectric conversion efficiency.

[0095] For example, along the thickness direction of the photovoltaic module, the thickness k1 of the second insulating block 14 may be set to 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, etc.

[0096] In the embodiment of the present application, the width of the second insulating block 14 is set to k2 along the second direction Y, satisfying 400μm≤k2≤800μm. This configuration ensures that the width of the second insulating block 14 is sufficient to cover the second fine grid 12, thereby blocking the second fine grid 12 and the first floating busbar 13. This prevents the second fine grid 12 and the first floating busbar 13 from conducting, which could cause a short circuit in the photovoltaic module and affect the photovoltaic module's photoelectric conversion efficiency.

[0097] Furthermore, the above arrangement can also prevent the second insulating block 14 from being too large, and the second insulating block 14 from extending above the first fine gate 11 along the second direction Y, thereby affecting the reliability of the connection between the first fine gate 11 and the first floating main gate 13 .

[0098] For example, along the second direction Y, the width k2 of the second insulating block 14 may be set to 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, etc.

[0099] It should be noted that in the embodiment of the present application, the thickness k1 of the second insulating block 14 refers to the minimum thickness of the second insulating block 14 along the thickness direction of the photovoltaic module, which is greater than or equal to 15 μm, and the maximum thickness of the second insulating block 14 is less than or equal to 50 μm. The width k2 of the second insulating block 14 refers to the width of the second insulating block 14 projected on the first surface along the thickness direction of the photovoltaic module, and the width k2 satisfies 400 μm ≤ k2 ≤ 800 μm.

[0100] Optionally, 5 μm≤m1≤30 μm is satisfied; and / or, along the second direction Y, the width of the first fine gate 11 or the second fine gate 12 is m2, satisfying 10 μm≤m2≤150 μm.

[0101] The first fine grid 11 or the second fine grid 12 in the embodiment of the present application is usually made of silver, copper, or silver-copper alloy, which has a relatively high cost. If the thickness of the first fine grid 11 or the second fine grid 12 is relatively thick, the cost of the photovoltaic module will be relatively high, affecting the market competitiveness of the photovoltaic module. If the thickness of the first fine grid 11 or the second fine grid 12 is relatively thin, it will affect the reliability of the connection between the first fine grid 11 and the first suspended main grid 13, or the second fine grid 12 and the second suspended main grid, causing a local short circuit in the photovoltaic module, affecting the photoelectric conversion efficiency of the photovoltaic module. Therefore, along the thickness direction of the photovoltaic module, the thickness m1 of the first fine grid 11 or the second fine grid 12 is set to be greater than or equal to 5μm and less than or equal to 30μm.

[0102] For example, along the thickness direction of the photovoltaic module, the thickness m1 of the first fine grid 11 or the second fine grid 12 can be set to 5 μm, 8 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, etc.

[0103] If the width of the first fine grid 11 or the second fine grid 12 along the second direction Y is too small, the first fine grid 11 or the second fine grid 12 cannot collect the current generated by the solar cell 10 in a timely manner, affecting the current collection efficiency of the photovoltaic module and, in turn, the photovoltaic module's photoelectric conversion efficiency. If the width of the first fine grid 11 or the second fine grid 12 along the second direction Y is too large, the material usage of the first fine grid 11 or the second fine grid 12 increases, resulting in higher photovoltaic module costs. Furthermore, if the width of the second fine grid 12 is too large, the second insulating block 14 cannot block the second fine grid 12 from the first floating busbar 13, making the photovoltaic module susceptible to local short circuits and affecting the photovoltaic module's photoelectric conversion efficiency. Therefore, along the second direction Y, the width m2 of the first fine grid 11 or the second fine grid 12 is set to be greater than or equal to 10 μm and less than or equal to 150 μm.

[0104] For example, along the second direction Y, the width m2 of the first fine gate 11 or the second fine gate 12 may be set to 10 μm, 30 μm, 50 μm, 80 μm, 100 μm, 120 μm, or 150 μm.

[0105] Optionally, along the thickness direction of the photovoltaic module, a difference between the highest point of the second insulating block 14 and the lowest point of the first sub-suspended busbar 131 is within 10 μm.

[0106] In the embodiment of the present application, the difference between the highest point of the second insulating block 14 and the lowest point of the first sub-suspended busbar 131 is set to within 10 μm along the thickness direction of the photovoltaic module. The conductivity of the bonding layer 30 is weaker than that of the first sub-suspended busbar 131. To reduce the resistance between the first fine grid 11 and the first electrical connector 20 and improve conductivity, it is desirable that the thickness of the first sub-bonding layer 31 be smaller and the thickness of the first sub-suspended busbar 131 be thicker. Therefore, in the embodiment of the present application, the difference between the highest point of the second insulating block 14 and the lowest point of the first sub-suspended busbar 131 is set to within 10 μm, resulting in a smaller thickness of the first sub-bonding layer 31 at the first gap and a thicker thickness of the first sub-suspended busbar 131, thereby improving conductivity.

[0107] Furthermore, this arrangement minimizes the overall surface roughness of the bonding layer 30, preventing hidden cracks in the cells 10 during the photovoltaic module lamination process and reducing warping of the first electrical connector 20 after lamination, which could affect the photovoltaic module manufacturing yield. Furthermore, it minimizes thickness variations within the first floating busbar 13, reducing material usage, lowering the cost of the photovoltaic module, and improving its market competitiveness.

[0108] For example, along the thickness direction of the photovoltaic module, the difference between the highest point of the second insulating block 14 and the lowest point of the first sub-suspended busbar 131 can be set to 1 μm, 3 μm, 5 μm, 8 μm, 9 μm, etc.

[0109] Optionally, along the thickness direction of the photovoltaic module, the distance d between the first electrical connector 20 and the solar cell 10 satisfies 70 μm≤d≤150 μm.

[0110] Along the thickness of the photovoltaic module, the distance d between the first electrical connector 20 and the cell 10 is set to be greater than or equal to 70 μm and less than or equal to 150 μm. This prevents the first electrical connector 20 from being positioned too high, which could cause hidden cracks in the cell 10 during the photovoltaic module lamination process and affect the photovoltaic module's manufacturing yield. Furthermore, this can reduce the material usage of the bonding layer 30, further reducing the cost of the photovoltaic module.

[0111] It should be noted that the cell 10 in the embodiment of the present application includes a cell body and an electrode pattern disposed on the surface of the cell body. The electrode pattern includes a first fine grid 11, a second fine grid 12, a first floating busbar 13, and a second floating busbar. The cell body includes a substrate and layers such as a doping layer and a passivation layer superimposed on the substrate surface. The distance d between the first electrical connector 20 and the cell 10 refers to the distance between the cell body and the first electrical connector 20. In other words, it is the distance between the surface of the cell body closest to the first electrical connector 20 and the side of the first electrical connector 20 closest to the cell body.

[0112] For example, along the thickness direction of the photovoltaic module, the distance d between the first electrical connector 20 and the solar cell 10 may be 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, etc.

[0113] Optionally, the first floating main grid 13 in the embodiment of the present application includes first connection points spaced apart along the second direction Y and a first connection main grid connected between two adjacent first connection points; the bonding layer 30 is disposed between the first connection points and the first electrical connector 20 .

[0114] In an embodiment of the present application, along the first direction X, the width of the first connection point is larger than that of the first connection main grid, and the bonding layer 30 is arranged between the first connection point and the first electrical connection member 20. The first connection point and the first electrical connection member 20 are connected by the bonding layer 30, so that the connection between the first connection point and the first electrical connection member 20 is more reliable, thereby ensuring the photoelectric conversion efficiency of the photovoltaic module.

[0115] It should be noted that the first connection point in the embodiment of the present application can be a solder pad or other connection point. The projection of the first connection point on the plane where the battery cell 10 is located can be a square structure, a rectangular structure, an elliptical structure, a circular structure, or other special-shaped structures. In the embodiment of the present application, there are no excessive restrictions on the specific structure of the first connection point. In actual applications, technicians can set it as needed.

[0116] Optionally, along the first direction X, the width of the bonding layer 30 is greater than or equal to 0.8 times the width of the first electrical connector 20 , and less than or equal to the width of the first connection point.

[0117] In the embodiment of the present application, the width of the bonding layer 30 is set to be greater than or equal to 0.8 times the width of the first electrical connector 20 and less than or equal to the width of the first connection point along the first direction X. This ensures that the bonding layer 30 is wide enough to connect the first connection point and the first electrical connector 20, thereby improving the reliability of the connection between the first connection point and the first electrical connector 20.

[0118] Furthermore, the bonding layer 30 does not extend outside the first connection point along the first direction X, thereby preventing the bonding layer 30 from being electrically connected to the second fine grid 12 , thereby preventing a short circuit in the photovoltaic module and affecting the photovoltaic module's photoelectric conversion efficiency.

[0119] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.

[0120] Although alternative embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including alternative embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0121] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity from another, and do not necessarily require or imply any actual relationship or order between these entities. Moreover, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that an article or terminal device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such article or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the article or terminal device comprising the element.

[0122] The technical solutions provided by the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. At the same time, for those skilled in the art, according to the principles and implementation methods of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A back-contact photovoltaic module, characterized in that: include: A battery cell, wherein a first surface of the battery cell is provided with a plurality of first fine grids and a plurality of second fine grids extending in a first direction and arranged alternately at intervals in a second direction, and a first floating main grid extending in the second direction is further provided on the first surface of the battery cell, the first floating main grid is connected to the plurality of first fine grids, at least one second insulating block is provided between the first floating main grid and each of the second fine grids, and the first direction intersects with the second direction; A first electrical connector extends along the second direction and is connected to the first suspension busbar. A bonding layer is provided between the first electrical connector and the first suspension busbar. The bonding layer has a thickness h, which satisfies 15 μm≤h≤70 μm.

2. The back-contact photovoltaic module according to claim 1, characterized in that: The second insulating blocks include a plurality of second insulating blocks, the plurality of second insulating blocks are spaced apart along the second direction, and a first gap is provided between two adjacent second insulating blocks; Along the second direction, the bonding layer includes a first sub-bonding layer disposed at a position corresponding to the first gap and a second sub-bonding layer disposed above the second fine grid; The thickness of the first sub-joining layer is h1, and the thickness of the second sub-joining layer is h2, satisfying 1≤h1 / h2≤4.

3. The back-contact photovoltaic module according to claim 2, characterized in that: Satisfies 30μm≤h1≤70μm; and / or, 15μm≤h2≤50μm.

4. The back-contact photovoltaic module according to claim 1, characterized in that: The second insulating blocks include a plurality of second insulating blocks, the plurality of second insulating blocks are spaced apart along the second direction, and a first gap is provided between two adjacent second insulating blocks; Along the second direction, the first floating main grid includes a first sub-floating main grid arranged at a position corresponding to the first gap and a second sub-floating main grid arranged above the second fine grid; The thickness of the first sub-suspended main grid is L1, and the thickness of the second sub-suspended main grid is L2, satisfying 1.5≤L1 / L2≤5.

5. The back-contact photovoltaic module according to claim 4, characterized in that: Satisfies L1≥20μm; and / or, 5μm≤L2≤30μm.

6. The back-contact photovoltaic module according to claim 1, characterized in that: The second insulating blocks include a plurality of second insulating blocks, the plurality of second insulating blocks are spaced apart along the second direction, and a first gap is provided between two adjacent second insulating blocks; Along the second direction, the first suspension main grid includes a first sub-suspension main grid arranged at a position corresponding to the first gap and a third sub-suspension main grid arranged above the second insulating block; The thickness of the first sub-suspended main grid is L1, and the thickness of the third sub-suspended main grid is L3, satisfying L1>L3.

7. The back-contact photovoltaic module according to claim 1, characterized in that: The thickness of the second insulating block is k1, and the thickness of the first fine grid or the second fine grid is m1, satisfying 1.5≤k1 / m1≤6.

8. The back-contact photovoltaic module according to claim 7, characterized in that: Satisfy 15μm≤k1≤50μm; And / or, along the second direction, the width of the second insulating block is k2, satisfying 400 μm≤k2≤800 μm.

9. The back-contact photovoltaic module according to claim 7, characterized in that: Satisfy 5μm≤m1≤30μm; And / or, along the second direction, a width of the first fine gate or the second fine gate is m2, satisfying 10 μm≤m2≤150 μm.

10. The back-contact photovoltaic module according to claim 6, characterized in that: Along the thickness direction of the photovoltaic module, the difference between the highest point of the second insulating block and the lowest point of the first sub-suspended main grid is within 10 μm.

11. The back-contact photovoltaic module according to claim 1, characterized in that: Along the thickness direction of the photovoltaic module, the distance between the first electrical connector and the solar cell is d, which satisfies 70 μm≤d≤150 μm.

12. The back-contact photovoltaic module according to claim 1, characterized in that: The first suspended main grid includes first connection points spaced apart along the second direction and a first connection main grid connected between two adjacent first connection points; The bonding layer is disposed between the first connection point and the first electrical connection member.

13. The back-contact photovoltaic module according to claim 12, characterized in that: Along the first direction, the width of the bonding layer is greater than or equal to 0.8 times the width of the first electrical connector and less than or equal to the width of the first connection point.

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