Concealed photovoltaic module bus bar

Abstract

The utility model discloses a hidden photovoltaic module bus bar, a photovoltaic module comprises a plurality of groups of parallel battery pieces, the hidden photovoltaic module bus bar comprises an insulated bus bar frame and bus bar conducting strips electrically connected with the battery pieces, and the bus bar conducting strips are fixed on the bus bar frame. And the corresponding battery pieces between the adjacent groups with opposite end surfaces are isolated by the bus bar frame. According to the utility model, the space between the battery pieces can be greatly reduced, gaps in the photovoltaic module can be reduced, and the space occupied by the bus bar can be compressed, so that the saved space can be used for increasing the area of the battery pieces, the module can effectively receive light in a larger area, and finally the photovoltaic module with higher power can be produced. According to the utility model, the internal structure of the photovoltaic module is compact, the parts are tightly matched, the overall structural strength is improved, the use of glass glaze of the battery piece is reduced, and the probability of plate explosion is reduced.

Description

Technical Field

[0001] This utility model relates to a lighting fixture, and more specifically, to a concealed photovoltaic module busbar. Background Technology

[0002] Currently, in conventional photovoltaic crystalline silicon cell module layouts, due to structural limitations of the busbars, the welded busbars and cell strings occupy a significant amount of space, approximately 1% to 2% of the total module volume. If this area could be rationally utilized and used to expand the cell area, the effective power generation area of ​​the photovoltaic module could increase by 1% to 2%. However, existing products have not optimized or improved in this direction. Utility model patent CN212010998U discloses a photovoltaic module busbar structure and a photovoltaic module. This utility model, by creating grooves in the weldable layer to accommodate solder strips, ensures that the surface of the busbars after soldering is flush, avoiding the risk of fragmentation during lamination due to height inconsistencies between the busbars and solder strips. Furthermore, the curved busbar design, covered with a reflective layer, reflects light from the busbar area to the cell area, thereby improving the overall power generation efficiency of the photovoltaic module. However, this utility model does not improve the space utilization after the busbars and cell strings are welded, nor does it increase the effective power generation area of ​​the photovoltaic module. Utility Model Content

[0003] In existing photovoltaic crystalline silicon cell modules, the structural design of the busbar is not entirely reasonable, resulting in the busbar occupying a large space after being welded to the cell string, which affects the effective power generation area of ​​the photovoltaic module. To overcome this defect, this utility model provides a hidden photovoltaic module busbar, which can optimize the busbar structure, improve the space utilization after the busbar is welded to the cell string, and increase the effective power generation area of ​​the photovoltaic module.

[0004] The technical solution of this utility model is: a concealed photovoltaic module busbar. The photovoltaic module includes multiple sets of parallel solar cells. The concealed photovoltaic module busbar includes an insulated busbar frame and a busbar conductive sheet electrically connected to the solar cells. The busbar conductive sheet is fixed on the busbar frame, and the corresponding solar cells between adjacent sets with opposite end faces are isolated by the busbar frame. In conventional photovoltaic crystalline silicon solar cell modules, the solar cells and busbars are welded together by a conductor. To ensure safety, sufficient distance must be left between the solar cells. To maintain this safety distance, corresponding fixing structures are also required on the photovoltaic module. This results in large gaps and many components inside the photovoltaic module, which in turn encroaches on the space of the solar cells and reduces the effective area of ​​the solar cells. This invention achieves physical isolation of solar cells with a relatively thin busbar frame, which can also be arranged close to the edges of the cells. This significantly reduces the spacing between cells and the internal voids of the photovoltaic module, compressing the space occupied by the busbars. The saved space can then be used to increase the area of ​​the solar cells, enabling a larger area of ​​the module to effectively receive sunlight, ultimately producing higher-power photovoltaic modules. Furthermore, this busbar structure also makes the internal structure of the photovoltaic module compact, with tighter component fit, improving the overall structural strength.

[0005] Preferably, the busbar frame includes a connected plate and a groove. The busbar conductive sheet includes a straight portion and a bent portion. The straight portion is attached to the inner surface of the plate, and the bent portion is fitted into the groove. The solar cell is attached to the outer surface of the plate, and the end of the solar cell abuts against the outer wall of the groove. The busbar frame is designed to include a connected plate and a groove, and the busbar conductive sheet is divided into a straight portion and a bent portion. This design allows the straight portion to be attached to the inner surface of the plate, the bent portion to be fitted into the groove, and the end of the solar cell abutting against the outer wall of the groove. This structure not only further reduces the spacing between the solar cells but also makes the connection between the busbar conductive sheet and the solar cell more compact and concealed, which is beneficial for saving space and improving the aesthetics of the photovoltaic module. Furthermore, the glass body of the solar cell is translucent. To reduce light transmission and escape, the back surface of the solar cell needs to be coated with a glass enamel to increase the light blocking and reflectivity at the back surface interface. However, the heat absorption rate of the glass enamel and glass during the tempering process is different, resulting in more concentrated stress at the enamel-coated area, making it more prone to cracking. In this invention, the panel and solar cell overlap during use. The overlapping area blocks and reflects light penetrating the solar cell, allowing the light to be reabsorbed and reused by the solar cell. The overlapping area between the busbar frame and the solar cell does not require a glass enamel coating, indirectly improving the strength of the glass, enhancing the load-bearing capacity of the module, and reducing the probability of panel breakage.

[0006] Preferably, the tank wall has through holes, through which solder ribbons, welded to both the busbar conductive sheets and the solar cells, are threaded. The solder ribbons electrically connect the same-polarity electrodes of the solar cell string inside the busbar, achieving a concealed and compact connection and reducing the space occupied by the busbar. This design allows the same-polarity electrodes of the solar cell string to be electrically connected inside the busbar, achieving both concealment and compactness. By reducing the space occupied by the busbar, the area of ​​the solar cells can be further increased, improving the effective power generation area of ​​the photovoltaic module. Simultaneously, the use of solder ribbons also improves the reliability and stability of the connection.

[0007] Preferably, the plate and the channel are integrally molded. This integral molding design simplifies the manufacturing process of the busbar frame and improves production efficiency. At the same time, the integral molding also enhances the overall structural strength of the busbar frame, making it more durable and reliable.

[0008] Preferably, the busbar conductive sheet is bonded to the busbar frame. This bonding method is simple, quick, and requires no additional fasteners, reducing production costs. Simultaneously, the bonding method provides sufficient connection strength to ensure a stable connection between the busbar conductive sheet and the busbar frame.

[0009] Alternatively, the busbar conductive strip can be connected to the busbar frame using screws. This connection method offers higher connection strength and reliability, making it suitable for applications with more stringent connection requirements.

[0010] Preferably, the busbar frame is made of plastic. This plastic design reduces production costs, while plastic's excellent insulation and processing properties facilitate manufacturing and installation. Furthermore, plastic components offer some corrosion resistance and weather resistance, extending the lifespan of the photovoltaic modules.

[0011] Alternatively, the busbar frame can be made of ceramic. Ceramic materials offer higher hardness and corrosion resistance, can withstand higher temperatures and pressures, and are suitable for applications with higher performance requirements for photovoltaic modules, ensuring stable operation of the photovoltaic modules in harsh environments.

[0012] The beneficial effects of this utility model are:

[0013] This invention increases the effective power generation area of ​​photovoltaic modules. It can significantly reduce the spacing between solar cells and the internal voids of photovoltaic modules, compress the space occupied by busbars, and thus use the saved space to increase the area of ​​solar cells, achieving a larger effective light-receiving area for the module, and ultimately producing higher-power photovoltaic modules.

[0014] This invention improves the structural strength of photovoltaic modules. The internal structure of the photovoltaic module is compact, and the components fit together tightly, thus improving the overall structural strength.

[0015] This invention reduces the amount of glass enamel used in the solar cells, thus lowering the chance of the cells bursting. During use, the material overlaps with the solar cells to a certain extent. The overlapping areas block and reflect light that penetrates the solar cells, allowing it to be reabsorbed and reused. These overlapping areas reduce the amount of glass enamel used in the solar cells, indirectly increasing the strength of the glass, improving the load-bearing capacity of the module, and lowering the chance of the cells bursting. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of one structure of the present utility model.

[0017] Figure 2 This is a schematic diagram of one structure of the busbar frame in this utility model.

[0018] Figure 3 This is a diagram showing one usage state of the present invention.

[0019] Figure 4 This is another structural schematic diagram of the present invention.

[0020] Figure 5 This is a schematic diagram of another structure of the busbar frame in this utility model.

[0021] Figure 6 This is a schematic diagram of another usage state of this utility model.

[0022] In the figure, 1-busbar frame, 101-plate, 102-groove, 103-through hole, 104-welding strip, 105-edge, 2-busbar conductive sheet, 201-straight part, 202-bent part, 3-battery cell. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] Example 1:

[0025] like Figures 1 to 5As shown, a concealed photovoltaic (PV) module busbar is used as the common terminal for the electrodes of the 3 cells in a 60-cell photovoltaic module. The 3 cells in the PV module are arranged in six groups, with ten 3 cells arranged side-by-side in each group. This concealed PV module busbar includes a busbar frame 1 and a busbar conductive sheet 2. The busbar frame 1 is an insulator, and the busbar conductive sheet 2 is electrically connected to the 3 cells. The busbar frame 1 includes a plate 101 and a groove 102, one of each. The groove 102 has two side walls and a bottom connected between the side walls, forming a U-shape. One end of the plate 101 is connected to the top of one side wall, and the other end of the plate 101 is integrally provided with a baffle 105, which is perpendicular to the top surface of the plate 101. The plate 101 and the groove 102 are integrally molded from plastic, and the plastic incorporates white masterbatch, resulting in a white color after injection molding and providing good reflectivity. The plate 101 is 10mm wide and 2mm thick, and the groove 102 is 5mm deep and 8mm wide. The busbar conductive sheet 2 is made of copper and includes a straight portion 201 and a bent portion 202. The straight portion 201 and the bent portion 202 are integrally formed. The straight portion 201 is bonded to the inner surface of the plate 101 with high-performance conductive adhesive to ensure good electrical connection and stability. The end of the straight portion 201 abuts against the inner side of the retaining edge 105. The bent portion 202 is fitted into the groove 102. The battery cells 3 between adjacent groups are separated by the busbar frame 1, and the ends of the battery cells 3 are tightly abutted against the outer wall of the groove 102. Five through holes 103 arranged in a straight line are provided on the groove wall section corresponding to the solar cell 3. The diameter of the through holes 103 is 2mm and the spacing between them is 20mm. Solder strips 104 are threaded through the through holes 103. The solder strips 104 are made of tin-lead-copper alloy to ensure good conductivity and welding performance. In this embodiment, it is used as a busbar component for the first and last groups of solar cells 3 in a photovoltaic module.

[0026] When assembling photovoltaic modules, this concealed photovoltaic module busbar is placed between the first group of solar cells 3 and the front edge of the photovoltaic module, and between the last group of solar cells 3 and the rear edge of the photovoltaic module. The back of each solar cell 3 in each group is tightly against the outer surface of the panel 101, and the end of each solar cell 3 abuts against the outer wall of the groove 102. This eliminates the gaps between the first and last groups of solar cells 3 and the front and rear edges of the photovoltaic module, improving the structural strength of the photovoltaic module. When the photovoltaic module is working, light enters the solar cells 3 from the front. Some light is directly absorbed by the solar cells 3 for photoelectric conversion, while some light penetrates the solar cells 3, is blocked by the panel 101, and reflected back to the solar cells 3, thereby improving the light energy utilization rate. Tests show that compared to photovoltaic modules with traditional busbars, the photovoltaic module in this embodiment increases the effective power generation area by approximately 1.5% due to the reduced spacing between corresponding solar cells 3 in adjacent groups. Under standard illumination conditions, the power output is increased by 3-5W. Regarding structural strength, mechanical vibration and static load tests revealed a compact internal structure and tight component fit. The overlapping area between the busbar frame 1 and the solar cell 3 does not require the use of glass glaze. With a reduction of about 10% in the amount of glass glaze used, the glass strength is improved, which further improves the load performance of the module and can successfully withstand higher wind pressure and snow pressure, significantly reducing the chance of the panel bursting.

[0027] Example 2:

[0028] As shown in the figure, a concealed photovoltaic module busbar is used as the common terminal for the electrodes of the 3 cells in a 120-cell photovoltaic module. The 3 cells in the photovoltaic module are arranged in six groups, with twenty 3 cells arranged side by side in each group. This concealed photovoltaic module busbar includes a busbar frame 1 and a busbar conductive sheet 2. The busbar frame 1 is an insulator, and the busbar conductive sheet 2 is electrically connected to the 3 cells. The busbar frame 1 includes a plate 101 and a groove 102. Unlike embodiment 1, in this embodiment, there are two plates 101 and one groove 102, making the cross-section of the busbar frame 1 shaped like a "Z". The groove 102 has two side groove walls and a groove bottom connected between the groove walls, forming a U-shape. One end of the plate 101 is connected to the top of one side groove wall, and the other end of the plate 101 is integrally provided with a retaining edge 105, which is perpendicular to the top surface of the plate 101. The plate 101 and the tank 102 are integrally molded from plastic, with white masterbatch added to the plastic, resulting in a white color after injection molding and providing good reflectivity. The plate 101 is 12mm wide and 3mm thick, while the tank 102 is 6mm deep and 10mm wide. The busbar conductive sheet 2 is made of copper and includes a straight portion 201 and a bent portion 202. The straight portion 201 and the bent portion 202 are integrally molded. The straight portion 201 is bonded to the inner surface of the plate 101 with high-performance conductive adhesive to ensure good electrical connection and stability. The end of the straight portion 201 abuts against the inner side of the retaining edge 105. The bent portion 202 is fitted into the tank 102. The battery cells 3 between adjacent groups are separated by the busbar frame 1, and the ends of the battery cells 3 are tightly abutted against the outer wall of the tank 102. Five through holes 103 arranged in a straight line are provided on the groove wall section corresponding to the solar cell 3 in the groove body 102. The diameter of the through holes 103 is 2.5 mm and the spacing between them is 20 mm. Solder strips 104 are passed through the through holes 103. The solder strips 104 are made of tin-lead-bismuth-copper alloy to ensure good conductivity and welding performance. In this embodiment, it is used as a busbar component for the non-edge solar cell 3 group in a photovoltaic module. The rest is the same as in embodiment 1.

[0029] When assembling photovoltaic modules, the concealed photovoltaic module busbar is placed between adjacent groups of cells 3, achieving inter-group separation of cells 3. The back of each cell 3 in each group is tightly attached to the outer surface of the panel 101, and the end of the cell 3 abuts against the outer wall of the groove 102, eliminating gaps between adjacent groups of cells 3 and improving the structural strength of the photovoltaic module. When the photovoltaic module is working, light enters the cell 3 from the front. Some light is directly absorbed by the cell 3 for photoelectric conversion, while some light penetrates the cell 3, is blocked by the panel 101, and reflected back to the cell 3, thereby improving light energy utilization. Tests show that compared to photovoltaic modules with traditional busbars, the photovoltaic module in this embodiment increases the effective power generation area by approximately 1.8% due to the reduced spacing between corresponding cells 3 in adjacent groups. Under standard illumination conditions, the power output is increased by 6-8W. Regarding structural strength, mechanical vibration and static load tests revealed a compact internal structure and tight component fit. The overlapping area between the busbar frame 1 and the solar cell 3 does not require the use of glass glaze. With a reduction of about 15% in the amount of glass glaze used, the glass strength is improved, which further improves the load performance of the module and can successfully withstand higher wind pressure and snow pressure, significantly reducing the chance of the panel bursting.

[0030] Example 3:

[0031] A concealed photovoltaic (PV) module busbar is used as the common terminal for the electrodes of the 3 cells in a 60-cell photovoltaic module. The 3 cells in the PV module are arranged in six groups, with ten 3 cells arranged side-by-side in each group. This concealed PV module busbar includes a busbar frame 1 and busbar conductive sheets 2. The busbar frame 1 is an insulator, and the busbar conductive sheets 2 are electrically connected to the 3 cells. The busbar frame 1 includes two plates 101 and one groove 102, making the cross-section of the busbar frame 1 shaped like a "Z". The groove 102 has two side walls and a bottom connected between the side walls, forming a U-shape. One end of the plate 101 is connected to the top of one side wall, and the other end of the plate 101 is integrally provided with a retaining edge 105, which is perpendicular to the top surface of the plate 101. The plate 101 and the tank 102 are integrally molded from plastic, and the plastic is mixed with white masterbatch, resulting in a white color after injection molding and providing good reflectivity. The plate 101 is 10mm wide and 2mm thick, while the tank 102 is 5mm deep and 8mm wide. The busbar conductive sheet 2 is made of copper and includes a straight portion 201 and a bent portion 202. The straight portion 201 and the bent portion 202 are integrally molded. Unlike embodiment 1, in this embodiment, the straight portion 201 is fixed to the inner surface of the plate 101 with screws to ensure good electrical connection and stability. The end of the straight portion 201 abuts against the inner side of the retaining edge 105. The bent portion 202 is fitted into the tank 102. The battery cells 3 between adjacent groups are separated by the busbar frame 1, and the ends of the battery cells 3 are tightly abutted against the outer wall of the tank 102. Five through holes 103 arranged in a straight line are provided on the groove wall section corresponding to the solar cell 3 in the groove body 102. The diameter of the through holes 103 is 2mm and the spacing between them is 20mm. Solder strips 104 are passed through the through holes 103. The solder strips 104 are made of tin-lead-copper alloy to ensure good conductivity and welding performance. In this embodiment, it is used as a busbar component for the non-edge solar cell 3 group in a photovoltaic module. The rest is the same as in embodiment 1.

[0032] When assembling photovoltaic modules, the concealed photovoltaic module busbar is placed between adjacent groups of cells 3 to separate the cells 3 between groups. The back of each cell 3 in each group is tightly attached to the outer surface of the panel 101, and the end of the cell 3 abuts against the outer wall of the groove 102, eliminating gaps between adjacent groups of cells 3 and improving the structural strength of the photovoltaic module. When the photovoltaic module is working, light enters the cell 3 from the front. Some light is directly absorbed by the cell 3 for photoelectric conversion, while some light penetrates the cell 3, is blocked by the panel 101, and reflected back to the cell 3, thereby improving light energy utilization. Tests show that compared to photovoltaic modules with traditional busbars, the photovoltaic module in this embodiment increases the effective power generation area by approximately 1.5% due to the reduced spacing between corresponding cells 3 in adjacent groups. Under standard illumination conditions, the power output is increased by 3-5W. Regarding structural strength, mechanical vibration and static load tests revealed a compact internal structure and tight component fit. The overlapping area between the busbar frame 1 and the solar cell 3 does not require the use of glass glaze. With a reduction of about 10% in the amount of glass glaze used, the glass strength is improved, which further improves the load performance of the module and can successfully withstand higher wind pressure and snow pressure, significantly reducing the chance of the panel bursting.

[0033] Example 4:

[0034] A concealed photovoltaic (PV) module busbar is used as the common terminal for the electrodes of the 3 cells in a 120-cell photovoltaic module. The 3 cells in the PV module are arranged in six groups, with twenty 3 cells arranged side-by-side in each group. This concealed PV module busbar includes a busbar frame 1 and busbar conductive sheets 2. The busbar frame 1 is an insulator, and the busbar conductive sheets 2 are electrically connected to the 3 cells. The busbar frame 1 includes two plates 101 and one groove 102, making the cross-section of the busbar frame 1 shaped like a "Z". The groove 102 has two side walls and a bottom connected between the side walls, forming a U-shape. One end of the plate 101 is connected to the top of one side wall, and the other end of the plate 101 has an integrally formed baffle 105 perpendicular to the top surface of the plate 101. Unlike Embodiment 1, in this embodiment, the plate 101 and the tank 102 are integrally formed from ceramic and coated with a reflective layer, providing excellent reflectivity. The plate 101 is 12mm wide and 3mm thick, while the tank 102 is 6mm deep and 10mm wide. The busbar conductive sheet 2 is made of copper and includes a straight portion 201 and a bent portion 202. The straight portion 201 and the bent portion 202 are integrally formed. The straight portion 201 is fixed to the inner surface of the plate 101 with screws to ensure good electrical connection and stability. The end of the straight portion 201 abuts against the inner side of the retaining edge 105. The bent portion 202 is fitted into the tank 102. The battery cells 3 between adjacent groups are separated by the busbar frame 1, and the ends of the battery cells 3 are tightly abutted against the outer wall of the tank 102. Five through holes 103 arranged in a straight line are provided on the groove wall section corresponding to the solar cell 3 in the groove body 102. The diameter of the through holes 103 is 2.5 mm and the spacing between them is 20 mm. Solder strips 104 are passed through the through holes 103. The solder strips 104 are made of tin-lead-bismuth-copper alloy to ensure good conductivity and welding performance. In this embodiment, it is used as a busbar component for the non-edge solar cell 3 group in a photovoltaic module. The rest is the same as in embodiment 1.

[0035] When assembling photovoltaic modules, the concealed photovoltaic module busbar is placed between adjacent groups of cells 3, achieving inter-group separation of cells 3. The back of each cell 3 in each group is tightly attached to the outer surface of the panel 101, and the end of the cell 3 abuts against the outer wall of the groove 102, eliminating gaps between adjacent groups of cells 3 and improving the structural strength of the photovoltaic module. When the photovoltaic module is working, light enters the cell 3 from the front. Some light is directly absorbed by the cell 3 for photoelectric conversion, while some light penetrates the cell 3, is blocked by the panel 101, and reflected back to the cell 3, thereby improving light energy utilization. Tests show that compared to photovoltaic modules with traditional busbars, the photovoltaic module in this embodiment increases the effective power generation area by approximately 1.8% due to the reduced spacing between corresponding cells 3 in adjacent groups. Under standard illumination conditions, the power output is increased by 6-8W. Regarding structural strength, mechanical vibration and static load tests revealed a compact internal structure and tight component fit. The overlapping area between the busbar frame 1 and the solar cell 3 does not require the use of glass glaze. With a reduction of about 15% in the amount of glass glaze used, the glass strength is improved, which further improves the load performance of the module and can successfully withstand higher wind pressure and snow pressure, significantly reducing the chance of the panel bursting.

Claims

1. A concealed photovoltaic module busbar, wherein the photovoltaic module comprises multiple sets of parallel solar cells (3), characterized in that, The device includes an insulated busbar frame (1) and a busbar conductive sheet (2) electrically connected to the battery cell (3). The busbar conductive sheet (2) is fixed on the busbar frame (1). The corresponding battery cells (3) between adjacent groups are isolated by the busbar frame (1). The busbar frame (1) includes a connected plate (101) and a groove (102). The groove wall of the groove (102) is provided with a through hole (103). A welding strip (104) is welded to both the busbar conductive sheet (2) and the battery cell (3) through the through hole (103).

2. The concealed photovoltaic module busbar according to claim 1, characterized in that, The busbar conductive sheet (2) includes a straight part (201) and a bent part (202). The straight part (201) is attached to the inner surface of the plate (101), and the bent part (202) is adapted to be embedded in the groove (102). The battery sheet (3) is attached to the outer surface of the plate (101), and the end of the battery sheet (3) abuts against the outer wall of the groove (102).

3. The concealed photovoltaic module busbar according to claim 2, characterized in that, The plate (101) and the groove (102) are integrally formed.

4. The concealed photovoltaic module busbar according to claim 1, characterized in that, The busbar conductive sheet (2) is bonded to the busbar frame (1).

5. The concealed photovoltaic module busbar according to claim 1, characterized in that, The busbar conductive sheet (2) is connected to the busbar frame (1) by screws.

6. The concealed photovoltaic module busbar according to any one of claims 1 to 5, characterized in that, The busbar frame (1) is made of plastic.

7. The concealed photovoltaic module busbar according to any one of claims 1 to 5, characterized in that, The busbar frame (1) is a ceramic component.

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