Photovoltaic module
By combining conductive frames and conductive grid lines with insulating light-transmitting components, the problem of busbars obstructing solar cells is solved, thereby improving the photoelectric conversion efficiency and heat dissipation of photovoltaic modules.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-23
- Publication Date
- 2026-04-07
AI Technical Summary
The existing busbar structure blocks the area of the solar cells, which affects the photoelectric conversion efficiency of the photovoltaic module.
Multiple conductive grid lines arranged with conductive frames and spacing are connected to the metal electrodes of the same polarity of the end cells. The light reaches the area covered by the busbar structure by cooperating with the insulating light-transmitting element through the gaps between adjacent conductive grid lines.
It improves the light utilization rate of the end cells and the photoelectric conversion efficiency of the photovoltaic module, while also enhancing heat dissipation and module reliability.
Smart Images
Figure CN121815809A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a photovoltaic module. Background Technology
[0002] To improve the cell density and aesthetics of photovoltaic (PV) modules, busbars are typically placed on the back of the cells. However, the existing busbar structure obstructs parts of the cells, affecting their photoelectric conversion efficiency. Therefore, there is still room for improvement in the photoelectric conversion efficiency of PV modules. Summary of the Invention
[0003] In view of this, the present invention provides a photovoltaic module that, through the combination of a busbar structure and an insulating light-transmitting element, enables light to pass through the gaps in the busbar structure and the insulating light-transmitting element and be utilized by the solar cells, thereby effectively improving the photoelectric conversion efficiency of the photovoltaic module.
[0004] Specifically, the present invention provides the following technical solutions: This invention provides a photovoltaic module, comprising: a cover plate, an encapsulating film, a cell array, and a backsheet. The encapsulating film is used to encapsulate the cell array between the cover plate and the backsheet. The cell array includes: multiple cell strings, a busbar structure disposed on the back side of the end cells of the cell strings, and an insulating light-transmitting element disposed between the back side of the end cells and the busbar structure. The bus structure includes: a conductive frame and multiple conductive grid lines located within the conductive frame and spaced apart, wherein the multiple conductive grid lines and the conductive frame are an integral structure; The conductive frame and the multiple conductive grid lines are directly or indirectly connected to multiple metal electrodes of the same polarity on the front or back of the end cell; The multiple conductive grid lines and the gaps between adjacent conductive grid lines cooperate with the insulating light-transmitting element to allow light to reach the area covered by the busbar structure on the back of the end cell.
[0005] The technical solution of the first aspect of the above invention has the following advantages or beneficial effects: The photovoltaic module provided in this embodiment of the invention achieves current collection by cooperating with multiple conductive grid lines located within the conductive frame and spaced apart, which are directly or indirectly connected to multiple metal electrodes of the same polarity on the front or back of the end cell. Furthermore, by cooperating with the insulating light-transmitting element through the gaps between adjacent conductive grid lines, light can reach the area covered by the current collection structure on the back of the end cell, thereby improving the light utilization rate of the end cell and thus improving the photoelectric conversion efficiency of the end cell and the photovoltaic module. Attached Figure Description
[0006] Figure 1This is a cross-sectional structural diagram of a photovoltaic module provided according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the back structure of a battery array according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the planar structure of the busbar structure of the first basic structure provided according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the planar structure of the busbar structure of the second basic structure provided in the embodiment of the present invention; Figure 5 This is a schematic diagram of a planar structure of a confluence structure based on a deformable structure of a first basic structure, according to an embodiment of the present invention. Figure 6A This is a schematic diagram of a first three-dimensional structure of the busbar structure provided according to an embodiment of the present invention; Figure 6B This is a schematic diagram of a second three-dimensional structure of the busbar structure provided according to an embodiment of the present invention; Figure 7 This is a schematic diagram of a third three-dimensional structure of the busbar structure provided in an embodiment of the present invention; Figure 8 This is a schematic diagram showing the relative positional relationship between the busbar structure and the end battery cells of the first basic structure provided by the present invention. Figure 9 This is a schematic diagram showing the relative positional relationship between the busbar structure and the end battery cell of the first modified structure of the second basic structure provided by the embodiment of the present invention. Figure 10 This is a schematic diagram showing the relative positional relationship between the busbar structure and the end battery cell of the second modified structure of the second basic structure provided in the embodiment of the present invention; Figure 11 This is a schematic diagram showing the relative positional relationship between the busbar structure and the end battery cells of the second basic structure provided in the embodiment of the present invention; Figure 12 This is a schematic diagram of the first relative positional relationship between the busbar structure of the first basic structure provided by the embodiment of the present invention and the end battery cell and the insulating light-transmitting element; Figure 13 This is a schematic diagram showing the relative positional relationship between the deformed structure of the busbar structure based on the first basic structure and the end battery cell and insulating light-transmitting component according to an embodiment of the present invention. Figure 14 This is a schematic diagram of a second relative positional relationship between the busbar structure of the first basic structure provided by the embodiment of the present invention and the end battery cell and insulating light-transmitting component; Figure 15 This is a three-dimensional structural schematic diagram of an insulating and light-transmitting component provided according to an embodiment of the present invention.
[0007] The attached figures are labeled as follows: 10-Cover plate; 20-Encapsulating film; 30-Battery array; 31-Battery string; 311-End cell; 32-Bushead structure; 321-Conductive frame; 3211-Long side frame; 3212-Wide side frame; 322-Conductive grid line; 3221-First grid line; 3222-Second grid line; 323-Gap; 33-Insulating transparent element; 331-Edge area of insulating transparent element; 332-Middle area of insulating transparent element; 40-Back plate. Detailed Implementation
[0008] The photovoltaic module provided in this embodiment of the invention mainly involves improvements to the relative positional relationship and connection relationship between the busbar structure 32 and the end cell 311 and the busbar structure 32.
[0009] It should be noted that the terms "first" and "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" and "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.
[0010] It is worth noting that, in the embodiments of the present invention, the front side of a structure (such as a photovoltaic module, a solar cell, etc.) generally refers to the main surface of the structure facing the sunlight during the operation of the solar cell, and the back side of a structure (such as a photovoltaic module, a solar cell, etc.) generally refers to the main surface of the structure facing away from the sunlight during the operation of the solar cell.
[0011] The cover plate 10, encapsulating film 20, and back plate 40 involved in the embodiments of the present invention are generally the same as those used in the prior art. More specifically, the encapsulating film 20 is generally formed by extruding an upper encapsulating film disposed between the battery array 30 and the cover plate 10 and a lower encapsulating film disposed between the battery array 30 and the back plate 40.
[0012] The battery string 31 involved in this embodiment of the invention is generally formed by connecting multiple battery cells in series. The battery cells can be solar cells with metal electrodes on both the front and back sides (i.e., metal electrodes on both sides), or back-contact solar cells with all metal electrodes on the back side. Furthermore, the metal electrodes involved in this embodiment of the invention can be fine grid lines disposed on the battery cell, or a combination of fine grid lines and main grid lines disposed on the battery cell. Generally, the battery cell includes multiple P-type conductive regions and multiple N-type conductive regions. The battery cell may only have fine grid lines. Specifically, a fine grid line on the battery cell is disposed on a P-type conductive region or an N-type conductive region, and the extension direction of the fine grid line is consistent with the extension direction of the P-type conductive region or N-type conductive region it is located in. Correspondingly, the bus structure 32 is connected to the fine grid lines of the same polarity on the battery cell. The metal electrodes of the solar cell can be fine grid lines and main grid lines disposed on the solar cell. Specifically, a fine grid line on the solar cell is disposed on a P-type conductive region or an N-type conductive region and the extension direction of the fine grid line is consistent with the extension direction of the P-type conductive region or N-type conductive region where it is located. The main grid line is connected in series with multiple fine grid lines disposed in multiple P-type conductive regions or multiple fine grid lines disposed in multiple N-type conductive regions. Correspondingly, the bus structure 32 is connected to the main grid line of the same polarity on the solar cell.
[0013] in, Figure 1 A cross-sectional structural diagram of a photovoltaic module provided in an embodiment of the present invention is shown; Figure 2 A schematic diagram of the back structure of the battery array provided in an embodiment of the present invention is shown; Figures 3 to 5 Schematic diagrams of two different busbar structures are shown; Figure 6A , Figure 6B and Figure 7 A three-dimensional structural diagram of two types of busbar structures is shown; Figures 8 to 11 A schematic diagram of a planar structure showing the connection relationship between different busbar structures and end cells; Figures 12 to 14 A cross-sectional schematic diagram showing the connection relationship between different busbar structures and end cells; Figure 15 A three-dimensional structural schematic diagram of the insulating light-transmitting component is shown.
[0014] Specifically, such as Figure 1 and Figure 2 As shown, the photovoltaic module provided in this embodiment of the invention may include: a cover plate 10, an encapsulating film 20, a cell array 30, and a backsheet 40. The encapsulating film 20 is used to encapsulate the cell array 30 between the cover plate 10 and the backsheet 40. More specifically, the cell array 30 may include: a plurality of cell strings 31, a busbar structure 32 disposed on the back side of the end cell 311 of the cell strings 31, and an insulating light-transmitting element 33 disposed between the back side of the end cell 311 and the busbar structure 32. It is worth noting that... Figure 1 and Figure 2An exemplary diagram shows a battery string formed by connecting battery cells with bifacial metal electrodes, and a battery array 30 composed of these battery strings. Furthermore, in the battery array, the arrangement of the battery strings can be as follows: Figure 2 As shown, other arrangements are also possible, and are not limited here.
[0015] Furthermore, such as Figures 3 to 11 As shown, the busbar structure 32 may include: a conductive frame 321 and multiple conductive grid lines 322 located within the conductive frame 321 and spaced apart, the multiple conductive grid lines 322 and the conductive frame 321 being an integral structure; the conductive frame 321 and the multiple conductive grid lines 322 are directly or indirectly connected to multiple metal electrodes of the same polarity on the front or back of the end cell 311; the multiple conductive grid lines 322 and the gaps 323 between adjacent conductive grid lines 322 cooperate with the insulating light-transmitting element 33 to allow light to reach the area covered by the busbar structure 32 on the back of the end cell 311.
[0016] The integration of multiple conductive grid lines 322 with the conductive frame 321 is typically achieved by forming the busbar structure 32 through a single stamping step. Specifically, this is achieved by stamping a conductive metal sheet using a stamping machine. More specifically, while stamping gaps 323 between adjacent conductive grid lines 322 onto the conductive metal sheet, the portion of the conductive metal sheet remaining constitutes the conductive frame 321 and the multiple conductive grid lines 322 spaced apart within the conductive frame 321. In other words, the gaps 323 between adjacent conductive grid lines 322 are essentially hollowed-out areas stamped onto the conductive metal sheet.
[0017] In addition, regarding Figure 1 and Figure 2 In the photovoltaic module with the structure shown, the bus structure 32 on the end cell 311 of one battery string 31 near the middle region of the photovoltaic module is relatively independent from the bus structure 32 on the end cell 311 of another battery string 31 near the middle region of the photovoltaic module in the extension direction of the battery string 31. Subsequently, a connection can be established between the bus structure 32 on the end cell 311 of one battery string 31 near the middle region of the photovoltaic module and the bus structure 32 on the end cell 311 of another battery string 31 near the middle region of the photovoltaic module in the extension direction of the battery string 31 through circuits or other connection structures.
[0018] The photovoltaic module provided in this embodiment of the invention achieves the purpose of current collection by cooperating with the conductive frame 321 of the busbar structure 32 and multiple conductive grid lines 322 located within the conductive frame 321 and spaced apart, to directly or indirectly conduct to multiple metal electrodes of the same polarity on the front or back of the end cell 311. Furthermore, by cooperating with the insulating light-transmitting element 33 through the gap 323 between adjacent conductive grid lines 322, light can reach the area covered by the busbar structure on the back of the end cell 311, thereby improving the light utilization rate of the end cell 311 and thus improving the photoelectric conversion efficiency of the end cell 311 and the photovoltaic module.
[0019] Furthermore, the structure provided in this embodiment of the invention, by having the busbar structure 32 disposed on the back of the end cell 311, allows the busbar structure 32 to be hidden on the back of the end cell 311, thereby improving the density and photoelectric conversion efficiency of the photovoltaic module.
[0020] In addition, the gap 323 between adjacent conductive grid lines 322 included in the busbar structure 32 can improve the heat dissipation of the end cell 311. That is, in addition to heat dissipation on the main surface, the side adjacent to the gap 323 of the busbar structure 32 can also dissipate heat, which increases the heat dissipation area of the busbar structure 32, reduces the current transmission heat generation temperature, solves the heat generation problem in the busbar structure 32 during the current collection process, and thus improves the reliability of the photovoltaic module.
[0021] It is worth noting that the conductive frame 321 and multiple conductive grid lines 322 involved in the embodiments of the present invention can be directly or indirectly connected to multiple metal electrodes of the same polarity on the front or back of the end battery cell 311. This can mean that the conductive frame 321 and multiple conductive grid lines 322 are connected to multiple fine grid lines of the same polarity on the front or back of the end battery cell 311 through conductive wires or solder ribbons (understandably, for the structure in which multiple fine grid lines are connected to the conductive frame 321 and multiple conductive grid lines 322 through conductive wires or solder ribbons, the length direction of the busbar structure 32 is perpendicular to the fine grid lines). Alternatively, the conductive frame 321 and multiple conductive grid lines 322 can be connected to multiple main grid lines of the same polarity on the front or back of the end battery cell 311 through solder ribbons (understandably, for the structure in which multiple main grid lines are connected to the conductive frame 321 and multiple conductive grid lines 322 through conductive wires or solder ribbons, the length direction of the busbar structure 32 is perpendicular to the main grid lines).
[0022] Furthermore, the busbar structure 32 involved in the embodiments of the present invention can be applied only to the edge of the battery array 30 (i.e., the end cell 311 at one end of the battery string), or it can be applied to the end cells at both ends of the battery string. That is, in the photovoltaic module, the part involving busbars can all use the busbar structure 32 provided in the embodiments of the present invention, or only partially use the busbar structure 32 provided in the embodiments of the present invention.
[0023] It is worth noting that, regardless of whether the metal electrode connected to the busbar structure 32 is located on the front or back of the end cell 311, and regardless of whether the end cell 311 is a cell with double-sided metal electrodes or a cell with all metal electrodes located on the back, the structure provided in this embodiment of the invention will provide an insulating light-transmitting element 33 between the busbar structure 32 and the back of the end cell 311. This allows light to reach the area covered by the busbar structure 32 on the back of the end cell 311 through the gap 323 between the adjacent conductive grid lines 322 included in the busbar structure 32 and the insulating light-transmitting element 33, thereby improving light utilization and thus improving the photoelectric conversion efficiency of the photovoltaic module.
[0024] As can be seen from the above, the structural improvements involved in the embodiments of the present invention mainly involve the busbar structure 32 and the cooperation between the busbar structure 32 and the insulating light-transmitting element 33. The following will provide a detailed description of the busbar structure 32 and the cooperation between the busbar structure 32 and the insulating light-transmitting element 33.
[0025] In this embodiment of the invention, two basic busbar structures 32 are provided, and based on these two basic structures, a modified structure of the busbar structure 32 is also provided.
[0026] Specifically, the first basic structure of the bus structure 32 is as follows: Figure 3 and Figure 8 As shown, multiple conductive grid lines 322 are parallel, and their extension direction is perpendicular to the extension direction of the metal electrodes of the end cell 311. Each of the multiple metal electrodes of the same polarity on the front or back of the end cell 311 is fixedly connected to each of the multiple conductive grid lines 322. By designing multiple conductive grid lines 322 to be parallel, the gaps 323 between adjacent conductive grid lines 322 are also parallel, ensuring a stable electrical connection between the multiple conductive grid lines 322 and the metal electrodes, while effectively increasing the light transmission through the gaps 323 between adjacent conductive grid lines 322 and the insulating light-transmitting element 33, thereby improving the light utilization rate of the end cell 311.
[0027] Furthermore, in Figure 3 and Figure 8 On the first basic structure of the shown busbar structure 32, one of its variant structures can also be as follows: Figure 5 As shown, both the side surfaces of the conductive frame 321 corresponding to the gap and the side surfaces of the conductive grid line 322 corresponding to the gap are inclined slopes. For this deformed structure, as... Figure 13 As shown, the inclined surface can refract light, allowing more light to reach the back of the end cell 311, thereby further improving the light utilization rate of the end cell 311.
[0028] For the first basic structure and its variants, the width D1 of the gap between adjacent conductive grid lines 322 is 0.10 mm to 1.00 mm. For example, the width D1 of the gap between adjacent conductive grid lines 322 can be 0.10 mm, 0.40 mm, 0.50 mm, 0.70 mm, 0.90 mm, or 1.00 mm. By controlling the width D1 of the gap between adjacent conductive grid lines 322, the amount of light reaching the end cell 311 can be further increased, thereby further improving the photoelectric conversion efficiency of the end cell 311.
[0029] The second basic structure of bus structure 32: such as Figure 4 and Figure 11 As shown, the multiple conductive grid lines 322 may include: multiple first grid lines 3221 and multiple second grid lines 3222. The multiple first grid lines 3221 are parallel, and their extension directions are perpendicular to the extension direction of the metal electrodes of the end battery cell 311. The multiple second grid lines 3222 are parallel and intersect the multiple first grid lines 3221, and their extension directions are consistent with the extension direction of the metal electrodes of the end battery cell 311. One end of each of the multiple metal electrodes of the same polarity is fixedly connected to one end of the corresponding second grid line 3222. This second basic structure of the busbar structure 32 ensures the conductivity at each position in the busbar structure 32 while effectively increasing the current transmission path, thereby improving the current collection capability of the busbar structure 32.
[0030] Furthermore, in the second basic structure of the busbar structure 32, the gap 323 formed between the multiple first grid lines 3221 and the multiple second grid lines 3222 is generally a cuboid or cubic structure. Based on this, a variant structure of the second basic structure of the busbar structure 32 is as follows: Figure 9 and Figure 10 As shown, the cross-section of the gap 323 formed between the multiple first grid lines 3221 and the multiple second grid lines 3222 can be various shapes such as circular or regular hexagonal. This gap 323 allows more light to reach the back of the end cell 311.
[0031] More preferably, such as Figure 4 , Figure 9 , Figure 10 and Figure 11 As shown, for the second basic structure and the modified structure of the second basic structure of the busbar structure 32, the multiple second grid lines 3222 therein correspond one-to-one with the multiple metal electrodes of the same polarity of the end battery cell 311, so as to ensure current collection and transmission while making the busbar structure 32 have a larger area gap 323 as much as possible to improve light transmittance.
[0032] Preferably, such as Figure 4 As shown, for the second basic structure of the bus structure 32, the width D2 of the second grid line 3222 is greater than or equal to the width of the metal electrode to facilitate the positioning and connection of the metal electrode.
[0033] In addition, for the second basic structure or its variant structure of the busbar structure 32, the side of the conductive frame 321 corresponding to the gap 323, the side of the first grid line 3221 corresponding to the gap 323, and the side of the second grid line 3222 corresponding to the gap 323 are all inclined slopes. These inclined slopes can refract the light that reaches them, so that the refracted light reaches the back of the end battery cell 311 covered by the busbar structure 32, thereby increasing the amount of light reaching the end battery cell 311 and thus improving the light utilization rate of the end battery cell 311.
[0034] Furthermore, regardless of whether it is the first basic structure and its variants of the aforementioned busbar structure 32, or the second basic structure and its variants of the aforementioned busbar structure 32, such as Figures 3 to 11 As shown, the conductive frame 321 generally includes two opposite long side frames 3211 and two opposite wide side frames 3212. The two long side frames 3211 and the two wide side frames 3212 are connected end to end and are an integral structure.
[0035] Specifically, for the first basic structure and its variants of the busbar structure 32, the long side frame 3211 of the conductive frame 321 included in the busbar structure 32 is generally parallel to the conductive gate line 322 included in the first basic structure and its variants of the busbar structure 32. Furthermore, the width D3 of the long side frame 3211 of the conductive frame 321 is consistent with the width D4 of the conductive gate line 322, ensuring balanced current transmission in the busbar structure 32 while facilitating the fabrication of the busbar structure 32.
[0036] Furthermore, for the first basic structure and its variants of the busbar structure 32, the long side frame 3211 of the conductive frame 321 included in the busbar structure 32 is generally parallel to the first gate line 3221 included in the second basic structure and its variants of the busbar structure 32. Moreover, the width D3 of the long side frame 3211 of the conductive frame 321 is consistent with the width D5 of the first gate line 3221, ensuring balanced current transmission in the busbar structure 32 while facilitating the fabrication of the busbar structure 32.
[0037] In the embodiments of the present invention, regardless of whether it is the first basic structure and its variant structure of the above-mentioned busbar structure 32 or the second basic structure and its variant structure of the above-mentioned busbar structure 32, the ratio between the width of the conductive gate line 322 and the width of the gap 323 between adjacent conductive gate lines 322 is 1:1 to 1:3.
[0038] Specifically, such as Figure 3 As shown, for the first basic structure and its variant structure of the bus structure 32, the ratio between the width D4 of the conductive grid line 322 and the width D1 of the gap 323 between adjacent conductive grid lines 322 is 1:1 to 1:3. For example, the ratio can be 1:1, 1:2 or 1:3, etc.
[0039] In addition, such as Figure 4 As shown, for the second basic structure and its variant structure of the bus structure 32, the ratio between the width D5 of the first gate line 3221 and the width D1 of the gap 323 between adjacent conductive gate lines 322 is 1:1 to 1:3. For example, the ratio can be 1:1, 1:2 or 1:3, etc.
[0040] Understandably, for the first basic structure and its variants of the bus structure 32, the width D4 of the conductive gate line 322 can be determined based on the ratio between the width D4 of the conductive gate line 322 and the width D1 of the gap 323 between adjacent conductive gate lines 322, as well as the width D1 of the gap 323 between adjacent conductive gate lines 322. For the second basic structure and its variants of the bus structure 32, the width D5 of the first gate line 3221 can be determined based on the ratio between the width D5 of the first gate line 3221 and the width D1 of the gap 323 between adjacent conductive gate lines 322, as well as the width D1 of the gap 323 between adjacent conductive gate lines 322.
[0041] It is worth noting that the first basic structure and its variants, and the second basic structure and its variants of the aforementioned busbar structure 32 mainly refer to the cross-sectional structure of the busbar structure 32 parallel to its main surface. Furthermore, based on the first basic structure, its variants, the second basic structure, and its variants, the three-dimensional structure of the busbar structure 32 can have various structures.
[0042] Specifically, the first three-dimensional structure of the busbar structure 32, such as Figure 6A As shown, the busbar structure 32 is a cuboid structure. A second three-dimensional structure of the busbar structure 32 is shown below. Figure 6BAs shown, in the main surface of the busbar structure 32 near the end cell 311, the portion corresponding to the wide side frame 3212 and the conductive grid line 322 is further away from the end cell 311 than the portion corresponding to the long side frame 3211. Furthermore, the portions of the main surface of the busbar structure 32 near the end cell 311 corresponding to the wide side frame 3212 and the conductive grid line 322 are on the same plane. Therefore, a groove is formed in the portion of the main surface of the busbar structure 32 near the end cell 311 corresponding to the wide side frame 3212 and the conductive grid line 322, so that the portion of the busbar structure 32 corresponding to the wide side frame 3212 and the conductive grid line 322 corresponds to a thicker insulating transparent element 33, allowing the gap 323 and the insulating transparent element 33 to form a better light-transmitting structure. A third three-dimensional structure of the busbar structure 32, such as... Figure 7 As shown, on the main surface of the busbar structure 32 near the end cell 311, the portion corresponding to the wide side frame 3212 and the conductive grid line 322 is further away from the end cell 311 than the portion corresponding to the long side frame 3211. The portion of the main surface of the busbar structure 32 near the end cell 311 corresponding to the wide side frame 3212 and the conductive grid line 322 is an arc surface away from the end cell 311. This arc surface makes the insulating light-transmitting element 33 that it matches a semi-convex lens, thereby improving light concentration.
[0043] Furthermore, in embodiments of the present invention, such as Figure 6A and 6B As shown, the first basic structure of the bus structure 32 and its variant structures have a thickness of 0.1mm to 0.3mm for the conductive grid line 322. For example, the thickness of the conductive grid line 322 can be 0.1mm, 0.15mm, 0.2mm, 0.25mm or 0.3mm, etc.
[0044] Furthermore, for the second basic structure and its variants of the bus structure 32, the thickness of the first gate line 3221 and the thickness of the second gate line 3222 can be 0.1mm to 0.3mm. For example, the thickness of the first gate line 3221 and the thickness of the second gate line 3222 can be 0.1mm, 0.15mm, 0.2mm, 0.25mm, or 0.3mm, etc. By controlling the thickness of the conductive gate line 322 in the first basic structure and its variants of the bus structure 32, as well as the thickness of the first gate line 3221 and the thickness of the second basic structure of the bus structure 32, the current collection capability and the reliability and stability of the collected current of the bus structure 32 can be guaranteed.
[0045] Furthermore, in the embodiments of the present invention, regardless of the first basic structure and its variants of the busbar structure 32, or the second basic structure and its variants of the busbar structure 32, the conductive frame 321 included in the busbar structure 32 has multiple structures in the thickness direction.
[0046] Specifically, in the thickness direction, the busbar structure 32 includes a first structure of the conductive frame 321: as follows Figure 6A As shown, the conductive border 321 is a rectangular border. This first type of conductive border 321, in conjunction with the conductive gate line 322, forms the first three-dimensional structure of the bus structure 32 described above. The second structure of the conductive border 321 included in the bus structure 32 is as follows: Figure 6B As shown, the wide frame 3212 has a cuboid structure, and the distance from the wide frame 3212 to the back of the end battery cell 311 is greater than the distance from the long frame 3211 to the back of the end battery cell 311. This is to increase the amount of light reaching the back of the end battery cell 311 by cooperating with the busbar structure 32 and the insulating light-transmitting element 33. The second structure of the conductive frame 321, in conjunction with the conductive grid line 322, obtains the second three-dimensional structure of the busbar structure 32. The third structure of the conductive frame 321 included in the busbar structure 32 is as follows: Figure 7 As shown, the wide side frame 3212 of the conductive frame 321 included in the busbar structure 32 is an arched structure away from the back of the end cell 311. Figure 7 Taking the three-dimensional structure of the first basic structure of the busbar structure 32 as an example, the wide side frame 3212 is an arched structure away from the back of the end cell 311. Through this structure, the portion of the insulating light-transmitting element 33 corresponding to the area between the two wide side frames 3212 is made similar to a semi-convex lens, thereby improving the light-concentrating ability of the insulating light-transmitting element 33, thus increasing the energy of the light reaching the end cell 311 corresponding to the portion of the insulating light-transmitting element 33, and thus increasing the light absorption of the end cell 311. It is worth noting that... Figure 6A , Figure 6B and Figure 7 The structure shown is only an example of the first basic structure of the bus structure 32 to illustrate the relative positional relationship between the wide side border 3212 and the long side border 3211, based on... Figure 4 , Figures 9 to 11 Those skilled in the art can understand the structure of the second basic structure of the busbar structure 32 in the thickness direction.
[0047] In this embodiment of the invention, regardless of whether it is the first basic structure and its variants of the above-described busbar structure 32, or the second basic structure and its variants, the busbar structure 32 includes: a substrate and a welding layer enclosing the substrate. The substrate can be formed from one or more combinations of phosphor bronze, beryllium bronze, and oxygen-free copper, and its thickness can be 0.1 mm to 0.3 mm. For example, the thickness of the substrate can be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, or 0.3 mm. The welding layer enclosing the substrate can be one of tin-lead, tin-lead-bismuth, tin-bismuth-silver, and tin-silver-copper, and its thickness can be 0.05 μm to 0.25 μm. For example, the thickness of the welding layer can be 0.05 μm, 0.1 μm, 0.15 μm, 0.2 μm, or 0.25 μm. Specifically, for the bus structure 32, the solder layer can be formed by the following electroplating process: unwinding the coil - degreasing - washing with water - pickling - washing with water - tin plating - washing with water - drying - rewinding, wrapping the substrate. Alternatively, the solder layer can be formed by the following hot-dip plating process: unwinding the coil - annealing - pre-coating the surface with flux - hot-dip tin plating - online inspection - rewinding, wrapping the substrate.
[0048] Furthermore, regarding the aforementioned insulating light-transmitting element 33, exemplarily, such as... Figure 15 As shown, the first main surface of the insulating light-transmitting component 33 near the end battery cell 311 is in contact with the back of the end battery cell 311; the long edge 331 of the second main surface of the insulating light-transmitting component 33 away from the end battery cell 311 is a recessed surface relative to the middle region 332, wherein the thickness of the long edge 331 of the insulating light-transmitting component 33 is less than the thickness of the middle region 332 of the insulating light-transmitting component 33; the recessed surface of the second main surface of the insulating light-transmitting component 33 is in contact with the long edge 3211 of the conductive frame 321; the middle region of the second main surface of the insulating light-transmitting component 33 is in contact with multiple conductive grid lines 322. The middle region 332 of the second main surface of the insulating light-transmitting component 33 has a planar structure or an arc surface structure. Figure 15 An exemplary illustration shows that the middle region 332 of the second main surface of the insulating light-transmitting element 33 has a planar structure, which is consistent with... Figure 6B The shown busbar structure 32 is matched to ensure a reliable light transmission effect between the gap 323 of the busbar structure 32 and the middle region 332 of the insulating light-transmitting element 33. Additionally, the arc-shaped structure (not shown in the figure) of the middle region 332 of the second main surface of the insulating light-transmitting element 33 is combined with... Figure 7 The combination of the shown busbar structure 32 and the middle area 332 of the insulating light-transmitting element 33 can ensure a reliable light transmission effect.
[0049] Furthermore, in order to improve the light transmittance of the middle region 332 of the insulating light-transmitting element 33, the thickness of the long side frame 3211 of the insulating light-transmitting element 33 corresponding to the conductive frame 321 is generally 0.10mm to 0.65mm. For example, the thickness of the long side frame 3211 of the insulating light-transmitting element 33 corresponding to the conductive frame 321 can be 0.10mm, 0.25mm, 0.3mm, 0.4mm, 0.45mm, 0.5mm, 0.6mm, or 0.65mm, etc.
[0050] Taking the busbar structure 32 of the first basic structure or a modified structure of the first basic structure provided in the embodiments of the present invention as an example, its cooperation with the insulating light-transmitting element 33 is as follows: Figures 12 to 14 As shown. Figure 12 As shown, the metal electrode on the front side of the end cell 311 extends beyond the end cell 311 and bends to the back side of the end cell 311 (hereinafter referred to as the bent portion of the front metal electrode). The insulating light-transmitting element 33 is located between the bent portion of the front metal electrode and the back side of the end cell 311. The bent portion of the front metal electrode is located between the insulating light-transmitting element 33 and the busbar structure 32. Figure 12 It can be seen that light can pass through the gap 323 of the busbar structure 32 and through the insulating light-transmitting element 33 to reach the back of the end cell 311.
[0051] For the first type of basic structure, its fit with the insulating and light-transmitting component 33 is as follows: Figure 14 As shown, the metal electrode on the front side of the end cell 311 extends beyond the end cell 311 and bends to the back side of the end cell 311 (hereinafter referred to as the bent portion of the back metal electrode). The insulating light-transmitting member 33 is located between the bent portion and the unbent portion of the back metal electrode. Furthermore, the bent portion of the back metal electrode is located between the insulating light-transmitting member 33 and the busbar structure 32, from... Figure 14 It can be seen that light can pass through the gap 323 of the busbar structure 32 and through the insulating light-transmitting element 33 to reach the back of the end cell 311.
[0052] In addition, regarding the deformable structure of the first type of basic structure, from Figure 13 It can be seen that light can pass through the gap 323 of the confluence structure 32 and the side corresponding to the gap 323 is set as an inclined plane, so that the light can be refracted on the inclined plane, further increasing the amount of light reaching the end battery cell 311.
[0053] The above steps are provided only to help understand the method, structure, and core ideas of this invention. Those skilled in the art can make various improvements and modifications to this invention without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims.
Claims
1. A photovoltaic module, comprising: The battery array comprises a cover plate (10), an encapsulating film (20), a battery array (30), and a back plate (40). The encapsulating film (20) is used to encapsulate the battery array (30) between the cover plate (10) and the back plate (40). The battery array (30) comprises: a plurality of battery strings (31), a busbar structure (32) disposed on the back side of the end battery pieces (311) of the battery strings (31), and an insulating light-transmitting element (33) disposed between the back side of the end battery pieces (311) and the busbar structure (32). The bus structure (32) includes: a conductive frame (321) and a plurality of conductive grid lines (322) located within the conductive frame (321) and spaced apart, wherein the plurality of conductive grid lines (322) and the conductive frame (321) are an integral structure; The conductive frame (321) and the multiple conductive grid lines (322) are directly or indirectly connected to multiple metal electrodes of the same polarity on the front or back of the end battery cell (311); The multiple conductive grid lines (322) and the gaps (323) between adjacent conductive grid lines (322) cooperate with the insulating light-transmitting element (33) to allow light to reach the area covered by the busbar structure (32) on the back of the end battery cell (311).
2. The photovoltaic module according to claim 1, characterized in that, Multiple conductive grid lines (322) are parallel to each other, and their extension direction is perpendicular to the extension direction of the metal electrode of the end battery cell (311). Each of the plurality of metal electrodes of the same polarity on the front or back of the end cell (311) is fixedly connected to each of the plurality of conductive grid lines (322).
3. The photovoltaic module according to claim 1, characterized in that, The plurality of conductive gate lines (322) include: a plurality of first gate lines (3221) and a plurality of second gate lines (3222). Multiple first grid lines (3221) are parallel to each other, and their extension direction is perpendicular to the extension direction of the metal electrode of the end cell (311); Multiple second grid lines (3222) are parallel to each other and intersect multiple first grid lines (3221), and their extension direction is consistent with the extension direction of the metal electrode of the end cell (311); One end of each of the plurality of metal electrodes of the same polarity is fixedly connected to one end of the corresponding second gate line (3222).
4. The photovoltaic module according to claim 3, characterized in that, Each of the second grid lines (3222) corresponds one-to-one with a plurality of metal electrodes of the same polarity of the end battery cell (311); And / or, The width of the second gate line (3222) is greater than or equal to the width of the metal electrode.
5. The photovoltaic module according to claim 1, characterized in that, The width of the long side border (3211) of the conductive border (321) is the same as the width of the conductive grid line (322); And / or, The ratio between the width of the conductive grid line (322) and the width of the gap between adjacent conductive grid lines (322) is 1:1 to 1:
3.
6. The photovoltaic module according to any one of claims 1 to 5, characterized in that, The thickness of the conductive grid line (322) is 0.1mm~0.3mm.
7. The photovoltaic module according to any one of claims 1 to 5, characterized in that, The first main surface of the insulating light-transmitting element (33) near the end battery cell (311) is in contact with the back of the end battery cell (311); The long edge of the second main surface of the insulating light-transmitting element (33) away from the end battery cell (311) is a recessed surface relative to the middle region, wherein the thickness of the long edge of the insulating light-transmitting element (33) is less than the thickness of the middle region of the insulating light-transmitting element (33). The recessed surface of the second main surface of the insulating light-transmitting component (33) is in contact with the long side frame (3211) of the conductive frame (321); The middle region of the second main surface of the insulating light-transmitting element (33) is attached to the plurality of conductive grid lines (322).
8. The photovoltaic module according to claim 7, characterized in that, The middle area of the second main surface of the insulating light-transmitting element (33) is a planar structure or an arc-shaped structure.
9. The photovoltaic module according to claim 7, characterized in that, The conductive border (321) includes two opposing long borders (3211) and two opposing wide borders (3212), wherein, The two long side borders (3211) and the two wide side borders (3212) are connected end to end and are a single structure; The wide frame (3212) is an arched structure away from the back of the end battery cell (311); or, the wide frame (3212) is a cuboid structure, and the distance from the wide frame (3212) to the back of the end battery cell (311) is greater than the distance from the long frame (3211) to the back of the end battery cell (311).
10. The photovoltaic module according to any one of claims 1 to 5, 8 and 9, characterized in that, The side of the conductive frame (321) corresponding to the gap and the side of the conductive grid line (322) corresponding to the gap are both inclined slopes; And / or, The thickness of the long side frame (3211) of the insulating light-transmitting component (33) corresponding to the conductive frame (321) is 0.10mm~0.65mm; And / or, The width of the gap between adjacent conductive gate lines (322) is 0.10 mm to 1.00 mm; And / or, The busbar structure (32) is formed by one-step stamping.