Photovoltaic module

Abstract

The present application relates to the technical field of photovoltaic modules, and specifically discloses a photovoltaic module. The photovoltaic module comprises: a battery cell; a plurality of connecting wires, arranged at intervals on a surface of the battery cell; and a first adhesive layer, arranged on the side of the plurality of connecting wires away from the battery cell, the first adhesive layer being configured to fix the plurality of connecting wires to the surface of the battery cell. In a direction perpendicular to the plane where the battery cell is located, the thickness of the first adhesive layer is T1, and the height of the connecting wires is T2, where the ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.8.

Description

A photovoltaic module

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 13, 2023, with application number 202311181822.X and invention name “A Photovoltaic Module”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of photovoltaic modules, and in particular to a photovoltaic module. Background Art

[0003] Photovoltaic modules contain strings of cells, which convert solar energy into electricity. A string of cells consists of multiple cells spaced apart, with adjacent cells connected in series via solder ribbons to collect the current generated by the cells.

[0004] In the related art, one end of a soldering ribbon is usually soldered to the surface of a battery cell, and the other end of the soldering ribbon is soldered to the surface of another adjacent battery cell, thereby connecting the two adjacent battery cells in series.

[0005] However, the existing method of welding the welding ribbon to the surface of the battery cell has problems such as low welding efficiency and high cost.

[0006] Summary of the Invention

[0007] The purpose of this application is to provide a photovoltaic module.

[0008] Specifically, this application involves the following aspects:

[0009] The present application discloses a photovoltaic module, comprising: a battery cell; a plurality of connecting wires, the plurality of connecting wires being arranged at intervals on the surface of the battery cell; a first adhesive layer, the first adhesive layer being arranged on a side of the plurality of connecting wires away from the battery cell, the first adhesive layer being used to fix the plurality of connecting wires to the surface of the battery cell; along a direction perpendicular to the plane where the battery cell is located, the thickness of the first adhesive layer is T1, and the height of the connecting wires is T2, wherein the ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.8.

[0010] Optionally, the ratio of T1 to T2 is greater than or equal to 0.4 and less than or equal to 1.4.

[0011] Optionally, T1 is greater than or equal to 0.1 mm and less than or equal to 0.4 mm; T2 is greater than or equal to 0.15 mm and less than or equal to 0.35 mm.

[0012] Optionally, the first adhesive layer comprises a pre-crosslinked polymer adhesive material layer.

[0013] Optionally, the pre-crosslinking degree of the pre-crosslinked polymer adhesive material layer is greater than 40%.

[0014] Optionally, the pre-crosslinked polymer adhesive material layer is disposed on a side of the first adhesive layer close to the battery cell, and the pre-crosslinked polymer adhesive material layer is at least partially connected to the battery cell.

[0015] Optionally, the pre-crosslinked polymer adhesive material layer includes at least one of an EVA layer, a POE layer and a PVB layer.

[0016] Optionally, the first adhesive layer is a single-layer structure, and the single-layer structure is an EVA layer.

[0017] Optionally, the first adhesive layer is a multi-layer structure.

[0018] Optionally, the first adhesive layer is a double-layer structure, and the first adhesive layer of the double-layer structure includes an EVA layer and a POE layer, wherein the EVA layer is arranged on a side of the first adhesive layer close to the battery cell, and the EVA layer abuts against the battery cell.

[0019] Optionally, the connecting wire includes a connecting wire base and a bonding layer attached to the surface of the connecting wire base, and the connecting wire is electrically connected to the battery cell through the bonding layer; the melting point of the bonding layer is less than 165 degrees, and the bonding layer is one of a tin-lead-bismuth layer, a tin-bismuth-silver layer or a tin-indium layer.

[0020] Optionally, a transparent oxide conductive layer is provided on the surface of the cell, and the bonding layer is partially connected to the transparent oxide conductive layer.

[0021] Optionally, the connecting wire includes a connecting wire base, and the connecting wire base is electrically connected to the battery cell.

[0022] Optionally, the photovoltaic module further includes: a second adhesive layer, a cover plate and a back plate, wherein the second adhesive layer is arranged between the cover plate and the first adhesive layer, and / or the second adhesive layer is arranged between the back plate and the first adhesive layer.

[0023] Optionally, along a direction perpendicular to the plane where the battery cell is located, the sum of the thickness of the first adhesive layer and the thickness of the second adhesive layer is greater than or equal to 0.4 mm and less than or equal to 0.8 mm.

[0024] Optionally, a ratio of the thickness of the first adhesive layer to the sum of the thicknesses of the first adhesive layer and the second adhesive layer is in a range of 10% to 45%.

[0025] Optionally, at the location of the connecting line, along a direction perpendicular to the plane of the battery cell, the thickness of the first adhesive layer is greater than or equal to 80 μm and less than or equal to 180 μm, and the thickness of the second adhesive layer is greater than or equal to 30 μm and less than or equal to 150 μm.

[0026] Optionally, at the location of the connecting line, along a direction perpendicular to the plane where the battery cell is located, the thickness of the first adhesive layer is greater than the thickness of the second adhesive layer.

[0027] Optionally, the length of the battery cell is greater than or equal to 180 mm and less than or equal to 240 mm.

[0028] Optionally, the battery cell includes a battery cell without a busbar.

[0029] Optionally, a projection of the first adhesive layer in a direction perpendicular to the plane where the battery cell is located falls into the battery cell.

[0030] Optionally, the first adhesive layer is a sheet-like structure, and the first adhesive layer covers the plurality of connecting wires.

[0031] Optionally, the first adhesive layer is a strip structure, and the first adhesive layer includes a plurality of strips, and the plurality of strips are arranged at intervals on the surface of the battery cell.

[0032] Optionally, the plurality of strips are arranged at intervals on the surface of the battery cell along an extension direction perpendicular to the connecting lines; each of the strips covers a portion of the plurality of connecting lines.

[0033] Optionally, each of the strips covers one of the connecting lines.

[0034] Optionally, a plurality of the strips are arranged at intervals on the surface of the battery cell along the extension direction of the connecting wires, and each of the strips covers the plurality of connecting wires.

[0035] Optionally, the first adhesive layer includes at least one transparent conductive layer, and the transparent conductive layer at least partially directly covers the connecting line.

[0036] Optionally, the transparent conductive layer includes at least one of a polyaniline layer, a metal nanolayer and a graphene layer.

[0037] Optionally, the transparent conductive layer includes at least one of an acrylate resin layer, an epoxy acrylate resin layer, and an epoxy acrylate oligomer layer.

[0038] The present application discloses a photovoltaic module, comprising: a battery cell; a plurality of connecting wires, the plurality of connecting wires being arranged at intervals on the surface of the battery cell; a first adhesive layer, the first adhesive layer being arranged on a side of the plurality of connecting wires away from the battery cell, the first adhesive layer being used to fix the plurality of connecting wires to the surface of the battery cell; along a direction perpendicular to the plane where the battery cell is located, the thickness of the first adhesive layer is T1, and the height of the connecting wires is T2, wherein the ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.8.

[0039] The photovoltaic module disclosed in this application uses a first adhesive layer to secure multiple connecting wires to the surface of the cell. Compared to spot welding the connecting wires to the cell surface, this method of securing the connecting wires to the cell surface via the first adhesive layer is more efficient and less costly.

[0040] Furthermore, in the embodiment of the present application, the ratio of the thickness T1 of the first adhesive layer to the height T2 of the connecting wire, along a direction perpendicular to the plane of the cell, is set to be greater than or equal to 0.3 and less than or equal to 1.8. This prevents the connecting wire from shifting during the process of being fixed to the cell surface via the first adhesive layer, and the provision of the first adhesive layer does not cause reliability issues such as hidden cracks in the cell.

[0041] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following is a brief introduction to the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0043] FIG1 shows a schematic structural diagram of a photovoltaic module according to an embodiment of the present application;

[0044] FIG2 shows a second structural diagram of the photovoltaic assembly described in an embodiment of the present application;

[0045] FIG3 shows a third structural diagram of the photovoltaic assembly according to an embodiment of the present application;

[0046] FIG4 shows a cross-sectional view of the photovoltaic module at the connection line, along a direction perpendicular to the plane where the solar cells are located.

[0047] Reference numerals: 10: battery cell; 20: connecting wire; 21: connecting wire substrate; 22: bonding layer; 30: first adhesive layer; 40: second adhesive layer; 50: cover plate; 60: back plate. Specific embodiments

[0048] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0049] Referring to Figure 1, there is shown a structural schematic diagram 1 of the photovoltaic assembly described in an embodiment of the present application; referring to Figure 2, there is shown a structural schematic diagram 2 of the photovoltaic assembly described in an embodiment of the present application; referring to Figure 3, there is shown a structural schematic diagram 3 of the photovoltaic assembly described in an embodiment of the present application; referring to Figure 4, there is shown a cross-sectional view of the photovoltaic assembly at the connecting line, along a direction perpendicular to the plane where the battery cell is located.

[0050] As shown in Figures 1 to 4, an embodiment of the present application discloses a photovoltaic module, which includes: a battery cell 10; a plurality of connecting wires 20, which are arranged at intervals on the surface of the battery cell 10; a first adhesive layer 30, which is arranged on the side of the plurality of connecting wires 20 away from the battery cell 10, and the first adhesive layer 30 is used to fix the plurality of connecting wires 20 to the surface of the battery cell 10; along the direction perpendicular to the plane where the battery cell 10 is located, the thickness of the first adhesive layer 30 is T1, and the height of the connecting wire 20 is T2, wherein the ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.8.

[0051] The present application discloses a photovoltaic module comprising a plurality of cells 10, each of which is arranged at intervals. Cells 10 absorb solar energy and convert it into electrical energy. The photovoltaic module also comprises a plurality of connecting wires 20, each of which has one end arranged at intervals on the surface of one cell 10 and the other end arranged at intervals on the surface of another adjacent cell 10.

[0052] It should be noted that the connecting wire 20 in the embodiment of the present application is conductive. Specifically, the connecting wire 20 may be a soldering ribbon or any other type of connecting wire that can electrically connect two adjacent battery cells 10. The specific type of connecting wire 20 is not limited here, and in actual use, technicians can select it as needed.

[0053] As shown in FIG. 1 to FIG. 4 , the first adhesive layer 30 is disposed on a side of the plurality of connection wires 20 away from the battery cell 10 , so as to fix the plurality of connection wires 20 to the surface of the battery cell 10 through the first adhesive layer 30 .

[0054] During the processing of photovoltaic modules, multiple connecting wires 20 can be arranged at intervals on the surface of the battery cell 10, and then the first adhesive layer 30 can be set on the side of the connecting wires 20 away from the battery cell 10. The first adhesive layer 30 is thermally cured or light-cured so that the first adhesive layer 30 fixes the connecting wires 20 on the surface of the battery cell 10. At this time, the photovoltaic module has not been laminated, and the connecting wires 20 and the battery cell 10 are mainly in physical contact, with fewer electrical contact locations. After the photovoltaic module is laminated, the connecting wires 20 can be electrically connected to the surface of the battery cell 10. As shown in Figure 4, after lamination, the thickness of the first adhesive layer 30 of the photovoltaic module is T1, and the height of the connecting wires 20 is T2 in the direction perpendicular to the plane of the battery cell 10. The ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.8.

[0055] It should be noted that the connecting wire 20 in the embodiment of the present application generally includes a connecting wire base 21 and a bonding layer 22 attached to the connecting wire base 21. The height of the connecting wire 20 refers to the sum of the height of the connecting wire base 21 and the height of the bonding layer 22.

[0056] Table 1 shows the reliability and power status of the laminated photovoltaic modules when first adhesive layers 30 of different thicknesses and connecting wires 20 of different heights are arranged in multiple photovoltaic modules in a direction perpendicular to the plane of the cell 10.

[0057] Table 1 The reliability and power of photovoltaic modules when the photovoltaic modules have different thicknesses of the first adhesive layer and different heights of the connecting wires

[0058] As can be seen from Table 1, in the embodiment of the present application, the ratio of the thickness T1 of the first adhesive layer 30 to the height T2 of the connecting wire 20 can be set to 0.3, 0.6, 0.9, 1.2, 1.5, 1.8, etc. in a direction perpendicular to the plane of the solar cell 10. When the ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.8, the reliability of the laminated photovoltaic module is high, and the photovoltaic conversion efficiency of the laminated photovoltaic module is good.

[0059] For example, when the thickness T1 of the first adhesive layer 30 is 0.1 mm and the height T2 of the connecting wire 20 is 0.25 mm, the ratio of T1 to T2 is 0.4, perpendicular to the plane of the solar cell 10. In this case, the laminated photovoltaic module has good reliability, a power output of 589.36, and a good photoelectric conversion efficiency.

[0060] For example, when the thickness T1 of the first adhesive layer 30 is 0.3 mm and the height T2 of the connecting wire 20 is 0.25 mm, the ratio of T1 to T2 is 1.2, perpendicular to the plane of the solar cell 10. In this case, the laminated photovoltaic module has good reliability, a power output of 589.25, and a good photoelectric conversion efficiency.

[0061] For example, when the thickness T1 of the first adhesive layer 30 is 0.35 mm and the height T2 of the connecting wire 20 is 0.25 mm, the ratio of T1 to T2 is 1.75. In this case, the laminated photovoltaic module has good reliability, a power output of 584.97, and a good photoelectric conversion efficiency.

[0062] As shown in Table 1, when the thickness T1 of the first adhesive layer 30 is 0.05 mm and the height T2 of the connecting wire 20 is 0.25 mm, the ratio of T1 to T2 is 0.2, along a direction perpendicular to the plane of the cell 10. In this case, due to the large height difference of the first adhesive layer 30 at the location of the connecting wire 20, the connecting wire 20 can easily shift, resulting in poor contact between the connecting wire 20 and the cell 10.

[0063] In a direction perpendicular to the plane of the cell 10, when the thickness T1 of the first adhesive layer 30 is 0.4 mm and the height T2 of the connecting wire 20 is 0.2 mm, the ratio of T1 to T2 is 2. In this case, because the first adhesive layer 30 is typically a pre-crosslinked polymer adhesive material with poor fluidity, the first adhesive layer 30 will squeeze the connecting wire 20. The pressure exerted by the first adhesive layer 30 on the connecting wire 20 is relatively high, and this pressure can be transmitted to the cell 10, causing reliability issues such as hidden cracks in the cell 10.

[0064] The present application discloses a photovoltaic module, comprising: a cell 10; a plurality of connecting wires 20, the plurality of connecting wires 20 being arranged at intervals on the surface of the cell 10; and a first adhesive layer 30, the first adhesive layer 30 being disposed on a side of the plurality of connecting wires 20 away from the cell 10, the first adhesive layer 30 being used to secure the plurality of connecting wires 20 to the surface of the cell 10. In a direction perpendicular to the plane of the cell 10, the first adhesive layer 30 has a thickness T1, and a height T2 of the connecting wires 20, wherein the ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.8. The photovoltaic module disclosed in the present application secures the plurality of connecting wires 20 to the surface of the cell 10 via the first adhesive layer 30. Compared to spot welding the connecting wires 20 to the surface of the cell 10, the method of securing the connecting wires 20 to the surface of the cell 10 via the first adhesive layer 30 in the present application is more efficient and less costly. Furthermore, in the embodiment of the present application, the ratio of the thickness T1 of the first adhesive layer 30 to the height T2 of the connecting wire 20 is set to be greater than or equal to 0.3 and less than or equal to 1.8 in a direction perpendicular to the plane of the battery cell 10. This prevents the connecting wire 20 from shifting during the process of being fixed to the surface of the battery cell 10 via the first adhesive layer 30, and the provision of the first adhesive layer 30 does not cause reliability issues such as hidden cracks in the battery cell 10.

[0065] Optionally, the ratio of T1 to T2 is greater than or equal to 0.4 and less than or equal to 1.4.

[0066] In order to further improve the reliability and photoelectric conversion efficiency of photovoltaic modules, in the embodiment of the present application, the ratio of the thickness T1 of the first adhesive layer 30 to the height T2 of the connecting line 20 is set to be greater than or equal to 0.4 and less than or equal to 1.4 along the direction perpendicular to the plane where the battery cell 10 is located.

[0067] For example, along a direction perpendicular to the plane of the battery cell 10 , the ratio of the thickness T1 of the first adhesive layer 30 to the height T2 of the connection line 20 can be set to 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, etc.

[0068] Of course, the above ratio is merely an example of the ratio of the thickness T1 of the first adhesive layer 30 to the height T2 of the connecting line 20 and is not intended to be limiting of the present application. In actual production, technicians can set the ratio of the thickness T1 of the first adhesive layer 30 to the height T2 of the connecting line 20 to any value between greater than or equal to 0.4 and less than or equal to 1.4 as needed.

[0069] As an optional implementation, T1 is greater than or equal to 0.1 mm and less than or equal to 0.4 mm; T2 is greater than or equal to 0.15 mm and less than or equal to 0.35 mm.

[0070] In the embodiment of the present application, the thickness T1 of the first adhesive layer 30 is set to be greater than or equal to 0.1 mm and less than or equal to 0.4 mm in a direction perpendicular to the plane of the battery cell 10. For example, the thickness T1 of the first adhesive layer 30 can be set to 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, etc.

[0071] In the embodiment of the present application, the thickness T1 of the first adhesive layer 30 is set to be greater than or equal to 0.1 mm in a direction perpendicular to the plane of the battery cell 10 to prevent the first adhesive layer 30 from being too thin. A too thin first adhesive layer 30 is prone to wrinkling during loading, which can cause problems such as misalignment of the connecting wires 20. The thickness T1 of the first adhesive layer 30 is set to be less than or equal to 0.4 mm to prevent the first adhesive layer 30 from being too thick, which can cause excessive pressure from the first adhesive layer 30 squeezing the connecting wires 20. This pressure can be transmitted to the battery cell 10, causing reliability issues such as hidden cracks in the battery cell 10.

[0072] In the embodiment of the present application, the height T2 of the connecting wire 20 is set to be greater than or equal to 0.15 mm and less than or equal to 0.35 mm in a direction perpendicular to the plane of the battery cell 10. For example, the height T2 of the connecting wire 20 can be set to 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, etc.

[0073] In this embodiment, the height T2 of the connecting wires 20, perpendicular to the plane of the cell 10, is set to be greater than or equal to 0.15 mm and less than or equal to 0.35 mm. This improves the reliability of the laminated photovoltaic module and its photoelectric conversion efficiency. Furthermore, the height difference of the first adhesive layer 30 at the location of the connecting wires 20 is appropriate, making it less likely to cause reliability issues such as displacement of the connecting wires 20.

[0074] As an optional embodiment, the first adhesive layer 30 includes a pre-crosslinked polymer adhesive material layer.

[0075] In the embodiment of the present application, the first adhesive layer 30 can be configured as a pre-crosslinked polymer adhesive layer. Specifically, the pre-crosslinked polymer adhesive layer can include a pre-crosslinked EVA layer. The pre-crosslinked EVA layer has advantages such as low fluidity and low cost. EVA is ethylene-vinyl acetate copolymer.

[0076] In addition, the pre-crosslinked polymer adhesive layer may also include a pre-crosslinked POE layer, which has the advantage of good resistance to PID effects. POE is divided into two types: one is a polymer of ethylene and butene, and the other is a polymer of ethylene and octene.

[0077] Of course, the pre-crosslinked polymer adhesive layer may also include any other pre-crosslinked polymer adhesive layer. In this regard, the present application embodiment does not impose specific restrictions, and in actual use, technicians can select as needed.

[0078] As an optional embodiment, the pre-crosslinking degree of the pre-crosslinked polymer adhesive material layer is greater than 40%.

[0079] In the embodiments of the present application, the pre-crosslinking degree of the pre-crosslinked polymer adhesive layer refers to the degree to which the polymer molecules in the pre-crosslinked polymer adhesive layer have solidified into an insoluble gel through a crosslinking reaction. It can also be considered the mass ratio of linear molecules in the pre-crosslinked polymer adhesive layer to crosslinked network molecules. It is understood that the higher the pre-crosslinking degree of the pre-crosslinked polymer adhesive layer, the stronger its adhesion.

[0080] In the embodiment of the present application, the pre-crosslinking degree of the pre-crosslinked polymer adhesive material layer is set to be greater than 40%. During the production process of the photovoltaic module, the pre-crosslinked polymer adhesive material layer can more firmly fix the connecting wire 20 to the surface of the solar cell 10.

[0081] As an optional embodiment, the pre-crosslinked polymer adhesive material layer is disposed on a side of the first adhesive layer 30 close to the battery cell 10 , and the pre-crosslinked polymer adhesive material layer is at least partially connected to the battery cell 10 .

[0082] In the embodiment of the present application, the pre-crosslinked polymer adhesive material layer can be disposed on the side of the first adhesive layer 30 close to the battery cell 10, and the pre-crosslinked polymer adhesive material layer is partially connected to the surface of the battery cell 10. The first adhesive layer 30 is bonded to the surface of the battery cell 10 through the pre-crosslinked polymer adhesive material layer, thereby improving the bonding reliability between the first adhesive layer 30 and the battery cell 10, thereby further better fixing the connecting wire 20 to the surface of the battery cell 10.

[0083] As an alternative embodiment, the pre-crosslinked polymer adhesive layer includes at least one of an EVA layer, a POE layer, and a PVB layer. For example, the pre-crosslinked polymer adhesive layer can be a single-layer structure. The single-layer pre-crosslinked polymer adhesive layer can be a pre-crosslinked EVA layer. The pre-crosslinked EVA layer has advantages such as low fluidity and low cost.

[0084] Of course, the pre-crosslinked polymer adhesive material layer may also be a multi-layer structure, and the pre-crosslinked polymer adhesive material layer of the multi-layer structure may include one or more of an EVA layer, a POE layer, and a PVB layer. Exemplarily, the pre-crosslinked polymer adhesive material layer of the multi-layer structure may include an EVA layer and a POE layer, wherein the EVA layer is disposed on the side of the first adhesive layer 30 close to the battery cell 10. The pre-crosslinked polymer adhesive material layer of the multi-layer structure may include an EVA layer and a PVB layer, wherein the EVA layer is disposed on the side of the first adhesive layer 30 close to the battery cell 10.

[0085] As an optional implementation manner, the first adhesive layer 30 may be provided as a single-layer structure, and the first adhesive layer 30 of the single-layer structure may be provided as an EVA layer.

[0086] Of course, the first adhesive layer 30 can also be configured as a multi-layer structure. For example, the first adhesive layer 30 can be configured as a double-layer structure, or the first adhesive layer 30 can be configured as a three-layer structure. In this regard, the embodiments of the present application do not impose too many restrictions. In actual use, technicians can configure it as needed.

[0087] As an optional embodiment, the first adhesive layer 30 can be a double-layer structure, wherein the double-layer first adhesive layer 30 includes an EVA layer and a POE layer, wherein the EVA layer is arranged on the side of the first adhesive layer 30 close to the battery cell 10, and the EVA layer abuts against the battery cell 10.

[0088] In the embodiment of the present application, the first adhesive layer 30 is configured as a double-layer structure, comprising an EVA layer and a POE layer. The EVA layer is disposed on the side of the first adhesive layer 30 close to the battery cell 10, and the POE layer is disposed on the side of the first adhesive layer 30 away from the battery cell 10.

[0089] In the embodiment of the present application, the connecting wire 20 is bonded to the surface of the cell 10 via an EVA layer to improve the reliability of the connection between the connecting wire 20 and the cell 10. The POE layer has good resistance to the PID effect. By providing the POE layer on the side of the first adhesive layer 30 away from the cell 10, the photovoltaic module can be improved in its resistance to the PID effect.

[0090] It should be noted that the first adhesive layer 30 in the embodiment of the present application can be an insulating adhesive layer, or a conductive adhesive layer. In the case where the first adhesive layer 30 is a conductive adhesive layer, the first adhesive layer 30 can include at least one transparent conductive layer. The transparent conductive layer at least partially directly covers the connecting wire 20 and has a portion bonded to the surface of the cell 10. The transparent conductive layer can effectively disperse the current and prevent current concentration in local areas. Furthermore, in the case where the cell is a heterojunction cell, the transparent conductive layer can directly contact the TCO layer on the cell surface, i.e., the transparent oxide conductive layer, to partially collect the current and improve the current collection efficiency.

[0091] As one of the optional implementations, the base material of the transparent conductive layer is a polymer layer, and the polymer layer may include at least one of an acrylate resin layer, an epoxy acrylate resin layer, and an epoxy acrylate oligomer layer.

[0092] Wherein, conductive substances are dispersed in the polymer layer. From the perspective of conductive substances, the transparent conductive layer may include at least one of a polyaniline layer, a metal nanolayer and a graphene layer.

[0093] It should be noted that in the embodiments of this application, the specific ratio of the base material and the conductive substance in the transparent conductive layer is not excessively limited. In actual production, the method can be implemented with reference to existing technologies. For details, please refer to documents such as CN102627823B, CN108753147A, and CN106279740A, and will not be repeated here.

[0094] For example, the first adhesive layer 30 can be configured as a double-layer structure, including a transparent conductive layer and a support layer. The support layer can be an EVA layer or a PET layer. The transparent conductive layer can effectively disperse the current, prevent current concentration in a local area, and partially collect the current.

[0095] As an optional embodiment, as shown in Figure 4, the connecting wire 20 includes a connecting wire base 21 and a bonding layer 22 attached to the surface of the connecting wire base 21, and the connecting wire 20 is electrically connected to the battery cell 10 through the bonding layer 22; the melting point of the bonding layer 22 is less than 165 degrees, and the bonding layer 22 is one of a tin-lead-bismuth layer, a tin-bismuth-silver layer, or a tin-indium layer.

[0096] As shown in Figure 4, the connecting wire 20 includes a connecting wire base 21 and a bonding layer 22 attached to the surface of the connecting wire base 21. Both the connecting wire base 21 and the bonding layer 22 are electrically conductive. The connecting wire base 21 is typically a copper strip. For example, the connecting wire base 21 can be an oxygen-free copper strip. Of course, the connecting wire base 21 can also be other metal strips, such as aluminum strips. This application does not impose specific limitations on this. In actual use, technicians can make choices based on their needs.

[0097] In the embodiment of the present application, the connecting wire 20 is electrically connected to the cell 10 via a bonding layer 22. The bonding layer 22 has a melting point of less than 165°C. During the photovoltaic module lamination process, the bonding layer 22 can alloy and interconnect with the metal grid lines on the surface of the cell 10. This electrically connects the connecting wire 20 to the cell 10, thereby collecting the current generated by the cell 10 through the connecting wire 20.

[0098] Specifically, the bonding layer 22 may be a tin-lead-bismuth layer, a tin-bismuth-silver layer, or a tin-indium layer. Of course, the bonding layer 22 may also be other conductive metal layers having a melting point less than 165 degrees. This application does not impose any additional restrictions on this. In actual use, technicians can set a suitable bonding layer 22 as needed.

[0099] As an optional embodiment, a transparent oxide conductive layer is provided on the surface of the cell 10 , and the bonding layer 22 is partially connected to the transparent oxide conductive layer.

[0100] In the embodiment of the present application, a transparent conductive oxide layer is provided on the surface of the cell 10, through which the current generated by the cell 10 is collected. Specifically, the transparent conductive oxide layer may be a tin oxide layer, or an indium tin oxide layer. In the embodiment of the present application, the specific material of the transparent conductive oxide layer is not excessively limited and can be selected as needed in actual use.

[0101] The bonding layer 22 is partially connected to the transparent conductive oxide layer. That is, the bonding layer 22 directly contacts the transparent conductive oxide layer and is electrically connected to the transparent conductive oxide layer. This allows for electrical connection between the connecting wires 20 and the cell 10, allowing the current generated by the cell 10 to be collected through the connecting wires 20.

[0102] As an optional embodiment, the connecting wire 20 includes a connecting wire base 21 , and the connecting wire base 21 is electrically connected to the battery cell 10 .

[0103] The connecting wire 20 in the embodiment of the present application may also only include a connecting wire base 21, and the connecting wire base 21 is fixed to the surface of the battery cell 10 through the first adhesive layer 30, so that the connecting wire base 21 is electrically connected to the battery cell 10 to collect the current generated by the battery cell 10.

[0104] As an optional embodiment, as shown in Figures 3 and 4, the photovoltaic module also includes: a second adhesive layer 40, a cover plate 50 and a back plate 60, wherein the second adhesive layer 40 is arranged between the cover plate 50 and the first adhesive layer 30, and / or the second adhesive layer 40 is arranged between the back plate 50 and the first adhesive layer 30.

[0105] As shown in Figures 3 and 4, the photovoltaic module in the embodiment of the present application further includes a second adhesive layer 40, a cover plate 50, and a back plate 60. The second adhesive layer 40 is disposed between the first adhesive layer 30 and the cover plate 50 so as to adhere the cover plate 50 to one side of the cell 10 via the second adhesive layer 40, and / or the second adhesive layer 40 is disposed between the first adhesive layer 30 and the back plate 50 so as to adhere the back plate 50 to the other side of the cell 10 via the second adhesive layer 40. Thus, the cell 10 can be fixed and protected by the cover plate 50 and the back plate 60.

[0106] As an optional embodiment, along a direction perpendicular to the plane where the battery cell 10 is located, the sum of the thickness of the first adhesive layer 30 and the thickness of the second adhesive layer 40 is greater than or equal to 0.4 mm and less than or equal to 0.8 mm.

[0107] In the embodiment of the present application, the sum of the thickness of the first adhesive layer 30 and the thickness of the second adhesive layer 40 is set to be greater than or equal to 0.4 mm and less than or equal to 0.8 mm in a direction perpendicular to the plane of the cell 10. This ensures the reliability of the photovoltaic module while controlling the production cost of the photovoltaic module.

[0108] If the sum of the thicknesses of the first adhesive layer 30 and the second adhesive layer 40 is set to less than 0.4 mm in a direction perpendicular to the plane of the cell 10, the laminated cells are prone to quality issues such as hidden cracks, affecting the reliability of the photovoltaic module. If the sum of the thicknesses of the first adhesive layer 30 and the second adhesive layer 40 is set to greater than 0.8 mm in a direction perpendicular to the plane of the cell 10, the cost of the photovoltaic module is increased and the photovoltaic module is prone to quality issues such as adhesive overflow and cell shifting.

[0109] Furthermore, both the first adhesive layer 30 and the second adhesive layer 40 can be considered as sealing layers. Since the first adhesive layer 30 has relatively poor fluidity, the thickness of the first adhesive layer 30 should not be too large. Generally speaking, the ratio of the thickness of the first adhesive layer 30 to the sum of the thicknesses of the first adhesive layer 30 and the second adhesive layer 40 is in the range of 10%-45%.

[0110] If the ratio of the thickness of the first adhesive layer 30 to the sum of the thicknesses of the first adhesive layer 30 and the second adhesive layer 40 is less than 10%, the first adhesive layer 30 is too thin and wrinkles are likely to form during the loading process. Furthermore, when the photovoltaic module is laminated, the first adhesive layer 30 is very likely to break at the location of the connecting wire 20, causing the connecting wire 20 to shift. If the ratio of the thickness of the first adhesive layer 30 to the sum of the thicknesses of the first adhesive layer 30 and the second adhesive layer 40 is greater than 45%, the first adhesive layer 30 is too thick. Due to the poor fluidity of the first adhesive layer 30, its own weight exerts a large pressure on the connecting wire 20, which can easily cause hidden cracks in the solar cell 10. Furthermore, the poor fluidity of the first adhesive layer 30 can lead to insufficient sealing of the photovoltaic module, affecting the reliability of the final packaging of the photovoltaic module.

[0111] As an optional embodiment, as shown in FIG4 , at the location of the connecting line 20 , along a direction perpendicular to the plane where the battery cell 10 is located, the thickness of the first adhesive layer 30 is greater than or equal to 80 μm and less than or equal to 180 μm, and the thickness of the second adhesive layer 40 is greater than or equal to 30 μm and less than or equal to 150 μm.

[0112] As shown in Figure 4, during the lamination process of the photovoltaic module, the first adhesive layer 30 and the second adhesive layer 40 are squeezed at the location of the connecting wire 20. Therefore, the thickness of the first adhesive layer 30 and the second adhesive layer 40 at the location of the connecting wire 20 is relatively small.

[0113] After lamination of the photovoltaic module, the thickness of the first adhesive layer 30 at the location of the connecting wires 20, along a direction perpendicular to the plane of the solar cells 10, is generally greater than or equal to 80 μm and less than or equal to 180 μm. Specifically, the thickness of the first adhesive layer 30 at the location of the connecting wires 20, along a direction perpendicular to the plane of the solar cells 10, can be set to 80 μm, 100 μm, 120 μm, 140 μm, 160 μm, 180 μm, etc.

[0114] After lamination of the photovoltaic module, the thickness of the second adhesive layer 40 at the location of the connecting wires 20, along a direction perpendicular to the plane of the solar cells 10, is generally greater than or equal to 30 μm and less than or equal to 150 μm. Specifically, the thickness of the second adhesive layer 40 at the location of the connecting wires 20, along a direction perpendicular to the plane of the solar cells 10, can be set to 30 μm, 60 μm, 90 μm, 120 μm, 150 μm, etc.

[0115] As an optional embodiment, at the location of the connecting wire 20 , along a direction perpendicular to the plane where the battery cell 10 is located, the thickness of the first adhesive layer 30 is greater than the thickness of the second adhesive layer 40 .

[0116] Before lamination of the photovoltaic module, the thickness of the second adhesive layer 40 is generally greater than the thickness of the first adhesive layer 30 at the location of the connecting wires 20, along a direction perpendicular to the plane of the solar cells 10. After lamination of the photovoltaic module, the thickness of the first adhesive layer 30 is greater than the thickness of the second adhesive layer 40 at the location of the connecting wires 20, along a direction perpendicular to the plane of the solar cells 10.

[0117] This is mainly because the first adhesive layer 30 is typically a pre-crosslinked polymer adhesive layer, which has lower fluidity than the second adhesive layer 40. During the lamination process, the first and second adhesive layers 30, 40 are squeezed and flowed, and the first adhesive layer 30 has lower fluidity. Therefore, the thickness change of the first adhesive layer 30 is smaller than that of the second adhesive layer 40.

[0118] As an optional embodiment, the length of the battery cell 10 is greater than or equal to 180 mm and less than or equal to 240 mm.

[0119] The length of the battery cell 10 in the embodiment of the present application is greater than or equal to 180 mm and less than or equal to 240 mm. Specifically, the length of the battery cell 10 can be 180 mm, 182 mm, 191.6 mm, 191.75 mm, 192, 210 mm, 220 mm, 230 mm, 240 mm, etc.

[0120] Exemplarily, the battery cell 10 may be a rectangular structure, and the specific dimensions of the rectangular structure battery cell 10 may include: (182±2)mm*(96±1)mm, (192±2)mm*(91±1)mm, (182±2)mm*(91±1)mm, (182±2)mm*(105±1)mm, etc.

[0121] Of course, in the embodiment of the present application, there is no limitation on the specific structure and size of the battery cell 10. Battery cells 10 of any structure and any size fall within the scope of protection of the present application. In actual use, technicians can select a suitable battery cell as the battery cell 10 as needed.

[0122] The battery cell 10 in the embodiment of the present application can be a battery cell without a busbar or a battery cell with a busbar. In actual use, technicians can make a choice according to their needs.

[0123] In the embodiment of the present application, the projection of the first adhesive layer 30 perpendicular to the plane of the cell 10 falls into the cell 10. The first adhesive layer 30 secures the connecting wires 20 to the surface of the cell 10. This prevents the first adhesive layer 30 from being too large, which could cause adhesive overflow during the lamination process of the photovoltaic module.

[0124] In an embodiment of the present application, the first adhesive layer 30 can be set as a sheet structure, so that the multiple connecting wires 20 set on the surface of the battery cell 10 can be covered by a sheet-like first adhesive layer 30, so that the multiple connecting wires 20 can be fixed to the surface of the battery cell 10 through a first adhesive layer 30.

[0125] Of course, the first adhesive layer 30 may also be configured as a strip structure, where the first adhesive layer 30 includes a plurality of strips, and the plurality of strips are arranged at intervals on the surface of the battery cell 10 .

[0126] Specifically, multiple strips can be arranged on the surface of the cell 10 at intervals perpendicular to the direction in which the connecting wires 20 extend. That is, the extending direction of the multiple strips is the same as the extending direction of the multiple connecting wires 20. Each strip can cover a portion of multiple connecting wires 20. For example, each strip can cover three connecting wires. Another example is that each strip can cover two connecting wires. Of course, each strip can also cover only one connecting wire 20.

[0127] In the embodiment of the present application, there are no excessive restrictions on the number of connecting lines 20 covered by each strip. In the actual production process, technicians can set it as needed.

[0128] In the embodiment of the present application, multiple strips may be arranged at intervals along the extension direction of the connecting wires 20 so that each strip covers multiple connecting wires 20 , thereby fixing the multiple connecting wires 20 to the surface of the battery cell 10 .

[0129] The present application discloses a photovoltaic module, comprising: a battery cell; a plurality of connecting wires, the plurality of connecting wires being arranged at intervals on the surface of the battery cell; a first adhesive layer, the first adhesive layer being arranged on a side of the plurality of connecting wires away from the battery cell, the first adhesive layer being used to fix the plurality of connecting wires to the surface of the battery cell; along a direction perpendicular to the plane where the battery cell is located, the thickness of the first adhesive layer is T1, and the height of the connecting wires is T2, wherein the ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.8.

[0130] The photovoltaic module disclosed in this application uses a first adhesive layer to secure multiple connecting wires to the surface of the cell. Compared to spot welding the connecting wires to the cell surface, this method of securing the connecting wires to the cell surface via the first adhesive layer is more efficient and less costly.

[0131] Furthermore, in the embodiment of the present application, the ratio of the thickness T1 of the first adhesive layer to the height T2 of the connecting wire, along a direction perpendicular to the plane of the cell, is set to be greater than or equal to 0.3 and less than or equal to 1.8. This prevents the connecting wire from shifting during the process of being fixed to the cell surface via the first adhesive layer, and the provision of the first adhesive layer does not cause reliability issues such as hidden cracks in the cell.

[0132] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0133] References herein to "one embodiment," "an embodiment," or "one or more embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Furthermore, please note that examples of the phrase "in one embodiment" herein do not necessarily all refer to the same embodiment. In the description provided herein, numerous specific details are described. However, it is understood that embodiments of the present application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques are not shown in detail so as not to obscure the understanding of this description.

[0134] In the claims, any reference signs placed between brackets shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in the claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present application may be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, and third etc. does not indicate any order. These words may be interpreted as names.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A photovoltaic module, wherein: include: Battery cells; A plurality of connecting wires, wherein the plurality of connecting wires are arranged at intervals on the surface of the battery sheet; a first adhesive layer, the first adhesive layer being disposed on a side of the plurality of connecting wires away from the battery cell, and the first adhesive layer being used to fix the plurality of connecting wires to a surface of the battery cell; Along a direction perpendicular to the plane where the battery cell is located, the thickness of the first adhesive layer is T1, the height of the connecting line is T2, and the ratio of T1 to T2 is greater than or equal to 0.3 and less than or equal to 1.

8.

2. The photovoltaic module according to claim 1, wherein: The ratio of T1 to T2 is greater than or equal to 0.4 and less than or equal to 1.

4.

3. The photovoltaic module according to claim 1, wherein: T1 is greater than or equal to 0.1 mm and less than or equal to 0.4 mm; T2 is greater than or equal to 0.15 mm and less than or equal to 0.35 mm.

4. The photovoltaic module according to claim 1, wherein: The first adhesive layer includes a pre-crosslinked polymer adhesive material layer.

5. The photovoltaic module according to claim 4, wherein: The pre-crosslinking degree of the pre-crosslinked polymer adhesive material layer is greater than 40%.

6. The photovoltaic module according to claim 4, wherein: The pre-crosslinked polymer adhesive material layer is disposed on a side of the first adhesive layer close to the battery cell. And the pre-crosslinked polymer adhesive material layer is at least partially connected to the battery cell.

7. The photovoltaic module according to claim 4, wherein: The pre-crosslinked polymer adhesive material layer includes at least one of an EVA layer, a POE layer and a PVB layer.

8. The photovoltaic module according to any one of claims 1 to 7, wherein: The first adhesive layer is a single-layer structure, and the single-layer structure is an EVA layer.

9. The photovoltaic module according to any one of claims 1 to 7, wherein: The first adhesive layer is a multi-layer structure.

10. The photovoltaic module according to claim 9, wherein: The first adhesive layer is a double-layer structure, and the first adhesive layer of the double-layer structure includes an EVA layer and a POE layer. The EVA layer is disposed on a side of the first adhesive layer close to the battery cell, and the EVA layer abuts against the battery cell.

11. The photovoltaic module according to claim 1, wherein: The connecting wire comprises a connecting wire substrate and a bonding layer attached to the surface of the connecting wire substrate, and the connecting wire is electrically connected to the battery cell through the bonding layer; The melting point of the bonding layer is less than 165 degrees, and the bonding layer is one of a tin-lead-bismuth layer, a tin-bismuth-silver layer or a tin-indium layer.

12. The photovoltaic module according to claim 11, wherein: A transparent oxide conductive layer is disposed on the surface of the cell, and a portion of the bonding layer is connected to the transparent oxide conductive layer.

13. The photovoltaic module according to claim 1, wherein: The connecting wire comprises a connecting wire substrate, and the connecting wire substrate is electrically connected to the battery cell.

14. The photovoltaic module according to claim 1, wherein: The photovoltaic module further includes: a second adhesive layer, a cover plate and a back plate. The second adhesive layer is disposed between the cover plate and the first adhesive layer, and / or the second adhesive layer is disposed between the back plate and the first adhesive layer.

15. The photovoltaic module according to claim 14, wherein: Along a direction perpendicular to the plane where the battery cell is located, the sum of the thickness of the first adhesive layer and the thickness of the second adhesive layer is greater than or equal to 0.4 mm and less than or equal to 0.8 mm.

16. The photovoltaic module according to claim 15, wherein: The ratio of the thickness of the first adhesive layer to the sum of the thickness of the first adhesive layer and the second adhesive layer is in a range of 10% to 45%.

17. The photovoltaic module according to claim 14, wherein: At the location of the connecting line, along the direction perpendicular to the plane where the battery cell is located, the thickness of the first adhesive layer is greater than or equal to 80 μm and less than or equal to 180 μm, and the thickness of the second adhesive layer is greater than or equal to 30 μm and less than or equal to 150 μm.

18. The photovoltaic module according to claim 17, wherein: At the location of the connecting line, along a direction perpendicular to the plane where the battery cell is located, the thickness of the first adhesive layer is greater than the thickness of the second adhesive layer.

19. The photovoltaic module according to claim 1, wherein: The length of the battery cell is greater than or equal to 180 mm and less than or equal to 240 mm.

20. The photovoltaic module according to claim 1, wherein: The battery cell includes a battery cell without a main grid.

21. The photovoltaic module according to claim 1, wherein: The projection of the first adhesive layer along a direction perpendicular to the plane where the battery cell is located falls into the battery cell.

22. The photovoltaic module according to claim 1, wherein: The first adhesive layer is a sheet-like structure, and the first adhesive layer covers the plurality of connecting wires.

23. The photovoltaic module according to claim 1, wherein: The first adhesive layer is a strip structure, and the first adhesive layer includes a plurality of strips, and the plurality of strips are arranged at intervals on the surface of the battery cell.

24. The photovoltaic module according to claim 23, wherein: The plurality of strips are arranged at intervals on the surface of the battery cell along an extension direction perpendicular to the connecting line; Each of the strips covers a portion of the plurality of connection lines.

25. The photovoltaic module according to claim 24, wherein: Each of the strips covers one of the connecting lines.

26. The photovoltaic assembly according to claim 23, wherein: The plurality of strips are arranged at intervals on the surface of the battery sheet along the extending direction of the connecting wires, and each of the strips covers the plurality of connecting wires.

27. The photovoltaic assembly according to claim 1, wherein: The first adhesive layer includes at least one transparent conductive layer, and the transparent conductive layer at least partially directly covers the connecting line.

28. The photovoltaic assembly according to claim 27, wherein: The transparent conductive layer includes at least one of a polyaniline layer, a metal nanolayer and a graphene layer.

29. The photovoltaic assembly according to claim 27, wherein: The transparent conductive layer includes at least one of an acrylate resin layer, an epoxy acrylate resin layer, and an epoxy acrylate oligomer layer.

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