Busbar and photovoltaic module

Abstract

The application discloses a bus bar and a photovoltaic module. The bus bar comprises a bus bar body and an insulating part. The insulating part covers the second surface, at least part of the third surface and the fourth surface; the insulating part also covers at least part of the fifth surface and the sixth surface; and / or the insulating part extends outward from both sides of the fifth surface and the sixth surface to beyond the fifth surface and the sixth surface; the insulating part comprises a bonding layer, a substrate layer and a reflective layer. According to the bus bar, the creeping distance to the frame is extended on the rest of the surfaces of the bus bar except the first surface through the design of the insulating part, the safety of the bus bar applied to the photovoltaic module is improved, the area of the photovoltaic module for accommodating the cell is increased, and the space utilization of the photovoltaic module is improved. Meanwhile, more light is reflected to the cell through the reflective layer of the bus bar, and the light utilization and the photoelectric conversion rate of the photovoltaic module are improved.

Description

Technical Field

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

[0002] In photovoltaic (PV) modules, busbars are the key conductors for current transmission. The creepage distance between the busbar and other structures directly affects the electrical safety performance of the module. In high-voltage systems (such as 1500V), insufficient creepage distance can lead to safety hazards such as electrical breakdown and short circuits. With increasing market demand for high-power modules, cell sizes are constantly increasing, further compressing internal space and making creepage distance requirements even more stringent. In related technologies, PV modules typically use butyl rubber or insulating tape to seal the edges to increase creepage distance. However, in the production and application of busbars and PV modules, problems such as insufficient creepage distance and limited insulation performance still exist, making them prone to short circuits, leakage, and other safety hazards, thus reducing safety performance. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one object of this invention is to provide a busbar that extends the creepage distance from the busbar to the frame, improves the safety of busbar applications in photovoltaic modules, and enhances the space utilization and light utilization rate of photovoltaic modules.

[0004] Another object of the present invention is to provide a photovoltaic module.

[0005] According to a first aspect of the present invention, a busbar includes: a busbar body, the outer surface of the busbar body including a first surface, a second surface, a third surface, a fourth surface, a fifth surface, and a sixth surface, the first surface and the second surface being opposite to each other, the first surface being adjacent to a battery cell, the third surface and the fourth surface being opposite to each other, the third surface being located on a light-receiving surface, the fifth surface and the sixth surface being opposite to each other, the fifth surface and the sixth surface being respectively connected between the two ends of the first surface, the second surface, the third surface, and the fourth surface; an insulating portion, the insulating portion covering the second surface and at least a portion of the third surface and the fourth surface; the insulating portion further covering at least a portion of the fifth surface and the sixth surface; and / or, the insulating portion extending outward from both sides where the fifth surface and the sixth surface are located to exceed the fifth surface and the sixth surface; the insulating portion includes an adhesive layer, a substrate layer, and a reflective layer, the adhesive layer and the reflective layer being respectively disposed on both sides of the substrate layer in the thickness direction, the adhesive layer being connected to the outer surface of the busbar body.

[0006] According to some embodiments of the present invention, the insulating portion covers the third surface and the fourth surface, and the insulating portion extends beyond the third surface and the fourth surface in the direction of the battery cell.

[0007] According to some embodiments of the present invention, the insulating portion covers the fifth surface and the sixth surface, and extends beyond the fifth surface and the sixth surface in the direction of the battery cell; and / or, the insulating portion extends outward from both sides of the fifth surface and the sixth surface to exceed the fifth surface and the sixth surface without covering the fifth surface and the sixth surface.

[0008] According to some embodiments of the present invention, the reflective layer includes a first reflective portion, a second reflective portion, and a spacer portion disposed between the first reflective portion and the second reflective portion. The first reflective portion and the second reflective portion have different reflective structures. When the insulating portion covers the busbar body, the first reflective portion is disposed on the third surface of the busbar body, the second reflective portion is disposed on the fourth surface of the busbar body, and the spacer portion is disposed on the second surface. Light on the light-receiving surface is reflected by the reflective structure of the first reflective portion to the front side of the adjacent battery cell, and light from the back side is reflected by the reflective structure of the second reflective portion to the back side of the adjacent battery cell.

[0009] According to some embodiments of the present invention, the reflective layer is a TiO2 high-reflection coating, a polyolefin-based reflective film, or a high-reflection fluorine coating; and / or, the substrate layer includes at least one of a polyethylene terephthalate layer, a polyolefin layer, and a silicone rubber layer.

[0010] According to some embodiments of the present invention, the thickness of the reflective layer is D1, wherein D1 satisfies: 10μm≤D1≤20μm; and / or the thickness of the substrate layer is D2, and the width of the substrate layer is W, wherein D2 and W respectively satisfy: 300μm≤D2≤500μm, 8mm≤W≤12mm; and / or the thickness of the adhesive layer is D3, wherein D3 satisfies: 30μm≤D3≤75μm.

[0011] According to some embodiments of the present invention, the insulating portion further includes a protective layer disposed on the side of the reflective layer away from the busbar body.

[0012] A photovoltaic module according to a second aspect of the present invention includes: a plurality of battery strings, the plurality of battery strings being connected in series by solder strips and arranged along a first direction; a plurality of busbars, the plurality of busbars being disposed on one side of the plurality of battery strings and arranged at intervals along the first direction, the busbars being connected to the battery strings by the solder strips, and the busbars being the busbars described in the first aspect of the present invention.

[0013] According to some embodiments of the present invention, the insulating portions of the plurality of busbars are provided in a one-to-one correspondence with the busbar body, respectively covering all surfaces of the outer side of each busbar body except for the first surface.

[0014] According to some embodiments of the present invention, the insulating portion of the busbar simultaneously covers the outer side of a plurality of busbar bodies.

[0015] According to some embodiments of the present invention, the insulating portion simultaneously covers the second, third, and fourth surfaces of a plurality of busbar bodies; for the fifth or sixth surfaces of the two outermost busbar bodies, both ends of the insulating portion cover the outermost fifth or sixth surfaces and extend beyond the fifth or sixth surfaces in the direction of the battery cell; for the fifth and sixth surfaces of the remaining busbar bodies between the two outermost busbar bodies, the insulating portion extends beyond the fifth and sixth surfaces in the first direction without covering the fifth and sixth surfaces; or, the insulating portion simultaneously covers the second, third, and fourth surfaces of a plurality of busbar bodies, and both ends of the insulating portion extend outward beyond the fifth and sixth surfaces of each busbar body without covering the fifth and sixth surfaces.

[0016] According to the embodiments of the present invention, the busbar extends the creepage distance from the busbar to the frame, improves the safety of the busbar application in photovoltaic modules, and helps to increase the area of ​​the photovoltaic module that accommodates the solar cells, thereby improving the space utilization rate of the busbar. At the same time, the reflective layer of the busbar helps to reflect more light onto the solar cells, thereby improving the light utilization rate of the photovoltaic module and thus improving the photoelectric conversion efficiency of the photovoltaic module.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the insulating portion of a busbar according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a photovoltaic module according to an embodiment of the present invention; Figure 3 This is a schematic diagram of a photovoltaic module according to another embodiment of the present invention; Figure 4 This is a schematic diagram of a photovoltaic module according to another embodiment of the present invention; Figure 5 This is a partial schematic diagram of a photovoltaic module according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the busbar body according to an embodiment of the present invention.

[0019] Figure label: 100. Busbar; 1. Busbar body; 11. First surface; 12. Second surface; 13. Third surface; 14. Fourth surface; 15. Fifth surface; 16. Sixth surface; 2. Insulating part; 21. Adhesive layer; 22. Substrate layer; 23. Reflective layer; 231. Reflective structure; 2311. Inclined surface; 232. First reflective part; 233. Second reflective part; 234. Spacer part; 24. Protective layer; 200. Photovoltaic modules; 201. Battery string; 202. Welding strip; 203. Frame; 204. Glass. Detailed Implementation

[0020] The following is for reference. Figures 1-6 A busbar 100 according to an embodiment of the first aspect of the present invention is described.

[0021] like Figures 1-6 As shown, the busbar 100 according to a first aspect embodiment of the present invention includes a busbar body 1 and an insulating portion 2.

[0022] Specifically, the outer surface of the busbar body 1 includes a first surface 11, a second surface 12, a third surface 13, a fourth surface 14, a fifth surface 15, and a sixth surface 16. The first surface 11 and the second surface 12 are opposite to each other, with the first surface 11 adjacent to the battery cell. The third surface 13 and the fourth surface 14 are opposite to each other, with the third surface 13 located on the light-receiving surface. The fifth surface 15 and the sixth surface 16 are opposite to each other, and the fifth surface 15 and the sixth surface 16 are respectively connected between the two ends of the first surface 11, the second surface 12, the third surface 13, and the fourth surface 14. The insulating portion 2 covers the second surface 12, and at least a portion of the third surface 13 and the fourth surface 14; the insulating portion 2 also covers at least a portion of the fifth surface 15 and the sixth surface 16; and / or, the insulating portion 2 extends outward from both sides of the fifth surface 15 and the sixth surface 16 to exceed the fifth surface 15 and the sixth surface 16; the insulating portion 2 includes an adhesive layer 21, a substrate layer 22 and a reflective layer 23, the adhesive layer 21 and the reflective layer 23 are respectively disposed on both sides of the substrate layer 22 in the thickness direction, and the adhesive layer 21 is connected to the outer surface of the busbar body 1.

[0023] For example, such as Figure 6 As shown, the first surface 11 is the rear surface of the busbar body 1, the second surface 12 is the front surface of the busbar body 1, the third surface 13 is the upper surface of the busbar body 1, the fourth surface 14 is the lower surface of the busbar body 1, the fifth surface 15 is the left surface of the busbar body 1, and the sixth surface 16 is the right surface of the busbar body 1.

[0024] For example, in Figures 1-6 In the example, the busbar body 1 is a conductive component used to concentrate and conduct current to achieve the distribution of large current. The first surface 11 of the busbar body 1 faces the solar cell. When the busbar 100 is applied to the photovoltaic module 200, the first surface 11 of the busbar body 1 is away from the glass 204. Therefore, the first surface 11 does not participate in the creepage path from the busbar 100 to the frame 203 of the photovoltaic module 200. Therefore, the first surface 11 of the busbar body 1 is not covered with the insulating part 2.

[0025] According to some embodiments of this application, the insulating portion 2 completely covers the second surface 12 of the busbar body 1. From the side of the second surface 12 toward the first surface 11, the insulating portion 2 covers the portions of the third surface 13, fourth surface 14, fifth surface 15, and sixth surface 16 adjacent to the second surface 12. Thus, the insulating portion 2 is generally arranged in a sleeve shape from the side of the second surface 12 toward the first surface 11, and part of the busbar body 1 is installed within the space enclosed by the insulating portion 2. Thus, the insulating portion 2 provides electrical isolation to the busbar body 1 from the above five surfaces, avoiding current leakage, short circuits, and conduction with other components, extending the creepage distance between the busbar body 1 and the frame 203, reducing safety hazards such as electrical breakdown and short circuits, and improving the safety of the busbar 100 when applied to the photovoltaic module 200.

[0026] According to other embodiments of this application, the insulating portion 2 completely covers the second surface 12 of the busbar body 1. From the side of the second surface 12 toward the first surface 11, the insulating portion 2 covers the portions of the third surface 13 and the fourth surface 14 adjacent to the second surface 12. The insulating portion 2 extends outward from both sides where the fifth surface 15 and the sixth surface 16 are located, respectively, beyond the fifth surface 15 and the sixth surface 16. Thus, the creepage distance is extended only by the insulating portion 2 extending beyond the fifth surface 15 and the sixth surface 16, without covering the outside of the fifth surface 15 and the sixth surface 16.

[0027] In related technologies, the fifth surface 15 and the sixth surface 16 of the busbar body 1 can form creepage distances to the frame 203 on the side away from the first surface 11. Through this design, during the creepage process between the fifth surface 15 and the sixth surface 16 of the busbar body 1 and the frame 203 on the side away from the first surface 11, the creepage distance needs to bypass the insulating portion 2 extending beyond the fifth surface 15 and the sixth surface 16, effectively extending the creepage distance between the fifth surface 15 and the sixth surface 16 and improving the safety of the busbar 100 when applied to the photovoltaic module 200.

[0028] Therefore, the creepage distance to the frame 203 is extended on all surfaces of the busbar 100 except the first surface 11 through the design of the insulating part 2, reducing safety hazards such as electrical breakdown and short circuit, and improving the safety of the busbar 100 when applied to the photovoltaic module 200. At the same time, while meeting the creepage distance requirement, the distance between the busbar 100 and the frame 203 is reduced compared to related technologies, which is conducive to increasing the area of ​​the photovoltaic module 200 that can accommodate the solar cells and improving the photoelectric conversion efficiency of the photovoltaic module 200.

[0029] It should be noted that the creepage distance of the fifth surface 15 and the sixth surface 16 can be extended in two ways. One way is to cover at least part of the insulating portion 2 on the side adjacent to the second surface 12. The other way is to extend the insulating portion 2 outward from both sides of the fifth surface 15 and the sixth surface 16 to beyond the fifth surface 15 and the sixth surface 16.

[0030] An adhesive layer 21, a substrate layer 22, and a reflective layer 23 are sequentially disposed on the outer surface of the busbar body 1. The adhesive layer 21 enhances the connection stability of the insulation part 2 on the surface of the busbar body 1, ensuring the insulation part 2 firmly covers the busbar body 1, stably extending the creepage distance of the busbar 100, effectively preventing short circuits and current leakage, and improving the electrical safety performance of the busbar 100. The substrate layer 22 serves as the main structural layer of the insulation part 2 and a functional layer for extending the creepage distance. It ensures excellent electrical insulation performance of the insulation part 2, achieving electrical isolation between the busbar 100 and other components. Simultaneously, the substrate layer 22 provides structural support and protection for the busbar body 1, improving overall structural stability. On the other side of the thickness direction of the substrate layer 22 is the reflective layer 23, which reflects light, thereby helping to improve the light utilization rate and photoelectric conversion efficiency of the photovoltaic module 200 using the aforementioned busbar 100.

[0031] For example, the adhesive layer 21 can be a hot melt adhesive or a pressure-sensitive adhesive.

[0032] According to an embodiment of the present invention, the busbar 100 has an insulating portion 2 that completely covers the second surface 12 of the busbar body 1, partially covers the third surface 13 and the fourth surface 14, and partially covers the fifth surface 15 and the sixth surface 16 or extends beyond the sides where the fifth surface 15 and the sixth surface 16 are located. Thus, the design of the insulating portion 2 extends the creepage distance to the frame 203 on all surfaces of the busbar 100 except the first surface 11, reducing safety hazards such as electrical breakdown and short circuits, and improving the safety of the busbar 100 when applied to the photovoltaic module 200. Furthermore, while meeting the creepage distance requirement, compared to related technologies, the distance between the busbar 100 and the frame 203 is reduced, which helps to increase the area of ​​the photovoltaic module 200 that accommodates the solar cells, improving the space utilization rate of the busbar 100. Simultaneously, the reflective layer 23 of the busbar 100 helps to reflect more light onto the solar cells, thereby improving the light utilization rate of the photovoltaic module 200 and enhancing the photoelectric conversion efficiency of the photovoltaic module 200.

[0033] According to some embodiments of the present invention, the insulating portion 2 covers the third surface 13 and the fourth surface 14, and extends beyond the third surface 13 and the fourth surface 14 in the direction of the solar cell. The insulating portion 2 not only completely covers the third surface 13 and the fourth surface 14 of the busbar body 1, but also extends beyond the third surface 13 and the fourth surface 14 in the direction from the second surface 12 toward the first surface 11. Therefore, during creepage, the end of the insulating portion 2 extending beyond the third surface 13 and the fourth surface 14 adjacent to the first surface 11 needs to be bypassed, extending the creepage distance and improving the safety of the busbar 100 when applied to the photovoltaic module 200.

[0034] According to some embodiments of the present invention, the insulating portion 2 covers the fifth surface 15 and the sixth surface 16, and extends beyond the fifth surface 15 and the sixth surface 16 in the direction of the solar cell. Thus, the insulating portion 2 covers all outer surfaces of the busbar body 1 except for the first surface 11, and extends beyond the fifth surface 15 and the sixth surface 16 in the direction from the second surface 12 toward the first surface 11. Therefore, during creepage, the end of the insulating portion 2 extending beyond the fifth surface 15 and the sixth surface 16 adjacent to the first surface 11 must be bypassed, blocking the creepage between the busbar body 1 and the frame 203 on the side away from the first surface 11. This helps to extend the creepage distance from the busbar 100 to the frame 203, improving the safety of the busbar 100 when applied to the photovoltaic module 200.

[0035] According to other embodiments of this application, the insulating portion 2 extends outward from both sides of the fifth surface 15 and the sixth surface 16, respectively, beyond the fifth surface 15 and the sixth surface 16 without covering them. Thus, the insulating portion 2 covers the second surface 12, the third surface 13, and the fourth surface 14 of the busbar body 1, and the insulating portion 2 covering the outside of the second surface 12, the third surface 13, and the fourth surface 14 can extend beyond the fifth surface 15 and the sixth surface 16. Therefore, during creepage, the insulating portion 2 must bypass the extended fifth surface 15 and the sixth surface 16, extending the creepage distance and improving the safety of the busbar 100 when applied to the photovoltaic module 200.

[0036] According to some embodiments of the present invention, with reference to Figure 1The reflective layer 23 includes a first reflective portion 232, a second reflective portion 233, and a spacer portion 234 disposed between the first reflective portion 232 and the second reflective portion 233. The first reflective portion 232 and the second reflective portion 233 have different reflective structures 231. When the insulating portion 2 covers the busbar body 1, the first reflective portion 232 is disposed on the third surface 13 of the busbar body 1, the second reflective portion 233 is disposed on the fourth surface 14 of the busbar body 1, and the spacer portion 234 is disposed on the second surface 12. Light from the light-receiving surface is reflected to the front of the adjacent battery cell by the reflective structure 231 of the first reflective portion 232, and light from the back is reflected to the back of the adjacent battery cell by the reflective structure 231 of the second reflective portion 233.

[0037] exist Figure 1 and Figure 6 In the example, the solar cell is disposed on one side of the first surface 11 of the busbar body 1. The third surface 13 of the busbar body 1 is provided with a first reflective portion 232, the fourth surface 14 is provided with a second reflective portion 233, and the second surface 12 is provided with a spacer portion 234. The third surface 13 directly receives direct sunlight and reflects it to the front of the solar cell through the reflective structure 231. The fourth surface 14 receives light reflected from the ground and reflects it to the back of the solar cell through the reflective structure 231. This increases the effective light-receiving area of ​​the solar cell and improves the light utilization rate and photoelectric conversion efficiency of the solar cell.

[0038] For example, in Figure 1 In the example, the reflective layer 23 includes six reflective structures 231. Three of the six reflective structures 231, forming a first reflective portion 232, can be located on the third surface 13 of the busbar body 1, while the other three reflective structures 231, forming a second reflective portion 233, can be located on the fourth surface 14 of the busbar body 1. This allows the three reflective structures 231 on the third surface 13 of the busbar body 1 to reflect light projected onto the inclined surface 2311 onto the solar cell, and the three reflective structures 231 on the fourth surface 14 of the busbar body 1 to reflect light projected onto the inclined surface 2311 onto the solar cell. Thus, the reflective structures 231 improve light utilization and enhance photoelectric conversion efficiency by reflecting light. Multiple reflective structures 231 can receive incident light from multiple angles, ensuring that light illuminating multiple surfaces of the busbar 100 can be utilized, improving the light reception range and utilization rate, and reducing power loss in the busbar 100.

[0039] Optionally, the reflective structure 231 can be a triangular prism. No specific limitation is made here. For example, the surface of the reflective structure 231 away from the substrate layer 22 is a slope 2311. The slope 2311 of the reflective structure 231 of the first reflective part 232 and the second reflective part 233 extends obliquely toward the side where the first surface 11 is located, so as to reflect light onto the solar cell.

[0040] For example, the angle α between the inclined surface 2311 and the substrate layer 22 can be 30° ≤ α ≤ 60°. When the angle between the inclined surface 2311 and the substrate layer 22 is less than 30°, the reflective area and the range of incident light reception are reduced, making it difficult to effectively reflect light from multiple angles and reducing light utilization. When the angle between the inclined surface 2311 and the substrate layer 22 is greater than 60°, the reflected light cannot be effectively utilized, resulting in light loss and reducing photoelectric conversion efficiency. Limiting the angle between the inclined surface 2311 and the substrate layer 22 to the above range is beneficial for the reflective structure 231 to balance reflective area and light utilization, thereby improving photoelectric conversion efficiency.

[0041] The angle β between the inclined surface 2311 and the surface perpendicular to the substrate layer 22 can be 50° ≤ β ≤ 70°. When the angle between the inclined surface 2311 and the surface perpendicular to the substrate layer 22 is less than 50°, light cannot be reflected to the effective working area, resulting in light waste and reduced photoelectric conversion efficiency. When the angle between the inclined surface 2311 and the surface perpendicular to the substrate layer 22 is greater than 70°, the area of ​​reflected light and the receiving range of incident light decrease, reducing light utilization. Limiting the angle between the inclined surface 2311 and the surface perpendicular to the substrate layer 22 to the above range is beneficial for increasing the reflective area while improving light utilization and photoelectric conversion efficiency, and also beneficial for the stability of the reflective structure 231.

[0042] According to some embodiments of the present invention, the reflective layer 23 is a TiO2 high-reflectivity coating, a polyolefin-based reflective film, or a high-reflectivity fluorine coating. The TiO2 high-reflectivity coating has high visible and near-infrared light reflectivity, which is beneficial for efficient light utilization. The TiO2 coating has strong chemical stability and good electrical insulation properties, making it suitable as the reflective layer 23 of the busbar 100. The polyolefin-based reflective film has high light reflectivity, good electrical insulation, and chemical stability, effectively reducing light loss and making it suitable for long-term outdoor environments. The high-reflectivity fluorine coating can achieve high diffuse reflection of visible / near-infrared light. Simultaneously, the high-reflectivity fluorine coating has anti-ultraviolet, anti-aging, high and low temperature resistance, and chemical corrosion resistance properties, allowing for long-term outdoor use. It also possesses good hydrophobicity and self-cleaning ability, effectively reducing dust adhesion, keeping the surface clean, and stabilizing optical performance after long-term use.

[0043] The substrate layer 22 includes at least one of a polyethylene terephthalate layer, a polyolefin layer, and a silicone rubber layer. The substrate layer 22 must meet the effective insulation requirements of IEC 61730-1:2023, IEC 62788-5-1, and IEC 60664 standards. The polyethylene terephthalate layer possesses superior electrical insulation, mechanical strength, and thermal stability, providing effective electrical isolation and physical protection for the busbar body 1, ensuring the stable operation of the busbar 100. The polyolefin layer effectively prevents moisture from entering the busbar body 1, forming reliable insulation and electrical isolation, reducing the risk of leakage and short circuits in surface discharge motors. The silicone rubber layer possesses superior resistance to high and low temperatures and electrical insulation, providing reliable insulation protection for the busbar body 1, preventing moisture intrusion, and improving the electrical safety and long-term stability of the busbar 100 in outdoor environments.

[0044] According to some embodiments of the present invention, with reference to Figure 1 The thickness of the reflective layer 23 is D1, where D1 satisfies: 10μm ≤ D1 ≤ 20μm. The thickness of the reflective layer 23 affects the reflection effect and adhesion. When the thickness of the reflective layer 23 is less than 10μm, the light reflectivity decreases, making it impossible to achieve efficient light reflection and utilization, and thus failing to achieve the expected reflection effect. When the thickness of the reflective layer 23 is greater than 20μm, phenomena such as cracking, warping, and decreased adhesion of the reflective layer 23 coating are prone to occur, while also increasing material costs. Therefore, by limiting the thickness of the reflective layer 23 within the above range, the reflectivity and light utilization rate of the reflective layer 23 are effectively improved, while also enhancing the structural stability of the reflective layer 23, allowing the reflective layer 23 to balance performance and production costs.

[0045] Reference Figure 1 The thickness of the substrate layer 22 is D2, and the width of the substrate layer 22 is W, where D2 and W satisfy the following conditions: 300μm≤D2≤500μm and 8mm≤W≤12mm, respectively. When the thickness of the substrate layer 22 is greater than 500μm, the adhesion between the edge of the insulating part 2 and the adhesive layer 21 is insufficient, and the corresponding adhesive layer 21 is prone to air bubbles. When the thickness of the substrate layer 22 is less than 300μm, the standard requirements for the substrate layer 22 are not met. Limiting the thickness of the substrate layer 22 within the above range provides effective electrical isolation for the busbar 100, avoids insulation breakdown caused by insufficient thickness, and reduces the unevenness of the adhesive layer 21 that can be connected due to excessive thickness, ensuring the long-term stable operation of the busbar 100.

[0046] The width of the substrate layer 22 affects the creepage distance, electric field clearance, and electric field distribution. When the width of the substrate layer 22 is less than 8 mm, it is difficult to ensure stable insulation between the busbar body 1 and the surrounding components in the width direction. This results in the creepage distance and electrical clearance failing to meet high-voltage insulation requirements, making it prone to discharge, leakage, and even flashover. It cannot provide sufficient electrical isolation for the busbar 100, leading to safety hazards such as short circuits and localized overheating. When the width of the substrate layer 22 is greater than 12 mm, it increases material usage and production costs, affecting the space utilization of the busbar 100. Limiting the width of the substrate layer 22 within the above range ensures stable insulation between the busbar body 1 and the frame 203 in the width direction, providing sufficient creepage distance and electrical clearance, effectively mitigating electric field concentration, improving insulation withstand capability, and enhancing the safety of the busbar 100.

[0047] Reference Figure 1 The thickness of the adhesive layer 21 is D3, where D3 satisfies: 30μm ≤ D3 ≤ 75μm. The thickness of the adhesive layer 21 affects the interlayer bonding strength. When the thickness of the adhesive layer 21 is less than 30μm, the bonding strength decreases, and local detachment is prone to occur, making it impossible to achieve a reliable connection between the busbar body 1 and the insulation part 2. When the thickness of the adhesive layer 21 is greater than 75μm, it is prone to displacement, failing to completely encapsulate the busbar body 1, reducing structural stability, and increasing thermal resistance, which is detrimental to heat dissipation of the busbar 100 and affects the service life of the busbar 100. Therefore, by limiting the thickness of the adhesive layer 21 within the above range, a tight bond is achieved between the busbar body 1 and the substrate layer 22, suppressing failure phenomena such as delamination and debonding.

[0048] According to some embodiments of the present invention, with reference to Figure 1 The insulating part 2 also includes a protective layer 24, which is disposed on the side of the reflective layer 23 away from the busbar body 1. The protective layer 24 protects the reflective layer 23 from wear, moisture corrosion, and the effects of the external environment, improving the environmental tolerance and long-term reliability of the reflective layer 23, while not affecting the reflection and utilization of light by the reflective layer 23. The protective layer 24 is transparent to facilitate the normal use of the reflective layer 23.

[0049] Reference Figure 1The sum of the thicknesses D4 of the protective layer 24 and the reflective layer 23 can be 10μm ≤ D4 ≤ 20μm. The sum of the thicknesses of the protective layer 24 and the reflective layer 23 affects the optical performance and stability of the reflective layer 23. When the sum of the thicknesses of the protective layer 24 and the reflective layer 23 is less than 10μm, the thickness of the protective layer 24 is too small to ensure the normal reflection of the reflective layer 23, making it difficult to protect the reflective layer 23 from environmental influences, or easily reducing the optical performance of the reflective layer 23. When the sum of the thicknesses of the protective layer 24 and the reflective layer 23 is greater than 20μm, it is easy for the protective layer 24 or the reflective layer 23 to warp or crack, while increasing the volume of the busbar 100 and reducing the assembly applicability of the busbar 100. Therefore, by limiting the sum of the thicknesses of the protective layer 24 and the reflective layer 23 to the above-mentioned range, the reflective layer 23 can be protected from the influence of the external environment, while ensuring the reflective effect of the reflective layer 23, thereby improving the structural stability of the protective layer 24 and the reflective layer 23 and increasing the light utilization rate of the reflective layer 23.

[0050] A photovoltaic module 200 according to a second aspect embodiment of the present invention includes: a plurality of cell strings 201 and a plurality of busbars 100. The plurality of cell strings 201 are connected in series via solder strips 202 and along a first direction (e.g., Figure 2 The multiple busbars 100 are arranged in a left-right direction as shown; multiple battery strings 201 are arranged on one side (e.g., in the left-right direction). Figure 2 The second direction shown (i.e., the up-down direction) and the arrangement at intervals along the first direction, the busbar 100 is connected to the battery string 201 by the solder strip 202, and the busbar 100 is the busbar 100 of the first aspect embodiment of the present invention.

[0051] For example, the solder strip 202 may be located between the busbar body 1 and the adhesive layer 21 of the busbar 100.

[0052] Multiple solar cells are connected in series to collect and boost the photovoltaic current, converting light energy into electrical energy and providing a stable power source for the photovoltaic module 200. Multiple busbars 100 are located on one side of the solar cell string 201 (e.g., ...). Figure 2 (As shown in the vertical direction) The busbar 100 is connected to the battery string 201 via solder strip 202. The busbar 100 collects and outputs the current generated by the battery string 201, while maintaining the stability of the internal conductive path of the photovoltaic module 200, reducing transmission losses, and improving the current output efficiency and electrical connection reliability of the photovoltaic module 200. Furthermore, by using the aforementioned busbar 100, the photovoltaic module 200 can accommodate larger battery cell sizes without changing the area of ​​the photovoltaic module 200, effectively increasing the power output of a photovoltaic module 200 of the same area.

[0053] According to the photovoltaic module 200 of the present invention, the busbar 100 is connected to the battery string 201 by the solder strip 202. The use of the busbar 100 helps to extend the creepage distance of the photovoltaic module 200, avoid safety hazards such as short circuit and current leakage, improve the safety of the photovoltaic module 200, improve the light utilization rate and photoelectric conversion efficiency, and enhance the power output of the photovoltaic module 200.

[0054] According to some embodiments of the present invention, with reference to Figure 3 The insulating portions 2 of multiple busbars 100 are arranged one-to-one with the busbar body 1, respectively covering all surfaces of each busbar body 1 except for the first surface 11. For example, in Figure 3 and Figure 6 In the example, the insulating part 2 can cover the second surface 12, third surface 13, fourth surface 14, fifth surface 15, and sixth surface 16 of each busbar body 1. While meeting the requirement of extending the creepage distance of multiple busbars 100, adjacent busbars 100 are separated by the insulating part 2, improving the safety of the high-voltage system. The insulating part 2 also serves as a limiter, support, and isolation, preventing direct contact between adjacent busbars 100 and structurally eliminating the risk of short circuits. The third surface 13 and the fourth surface 14 reflect light onto the solar cells to improve the photoelectric conversion efficiency of the photovoltaic module 200. At the same time, without changing the area of ​​the photovoltaic module 200, it can accommodate larger solar cell sizes, effectively improving the power output of photovoltaic modules 200 of the same area.

[0055] According to some embodiments of the present invention, with reference to Figure 2 and Figure 4 The insulating portion 2 of the busbar 100 simultaneously covers the outer side of multiple busbar bodies 1. For example, the second surfaces 12 of at least two busbars 100 are simultaneously covered by an insulating portion 2. This reduces the difficulty of setting the insulating portion 2, and also facilitates the extension or even blocking of creepage distance between the corresponding fifth surfaces 15 and sixth surfaces 16 between two adjacent busbars 100 through the extended insulating portion 2.

[0056] According to some embodiments of the present invention, with reference to Figure 2 The insulating portion 2 simultaneously covers the second surface 12, third surface 13, and fourth surface 14 of multiple busbar bodies 1. For the fifth surface 15 or sixth surface 16 of the two outermost busbar bodies 1, both ends of the insulating portion 2 cover the outermost fifth surface 15 or sixth surface 16 and extend beyond the fifth surface 15 or sixth surface 16 in the direction of the battery cell. For the fifth surface 15 and sixth surface 16 of the remaining busbar bodies 1 between the two outermost busbar bodies 1, the insulating portion 2 extends beyond the fifth surface 15 and sixth surface 16 in the first direction but does not cover the fifth surface 15 and sixth surface 16. Figure 2In the example, there is one insulating part 2, which covers the second surface 12, third surface 13, and fourth surface 14 of each busbar body 1 opposite to the first surface 11, and the fifth surface 15 and sixth surface 16 of the two busbars 100 located on opposite sides along the first direction. The fifth surface 15 and sixth surface 16 of the multiple busbar bodies 1 located in the middle of the first direction are extended or even blocked by the extended insulating part 2. This configuration simplifies the installation of the insulating part 2 and fully covers the surfaces of the multiple busbars 100 except for the first surface 11, extending the creepage distance, effectively avoiding risks such as short circuits and leakage, improving the insulation reliability and safety of the photovoltaic module 200, and increasing the power of the photovoltaic module 200 per unit area.

[0057] exist Figure 4 In the example, the insulating portion 2 simultaneously covers the second surface 12, third surface 13, and fourth surface 14 of multiple busbar bodies 1, and the insulating portion 2 extends outward from both ends along the first direction beyond the fifth surface 15 and sixth surface 16 of each busbar body 1 without covering the fifth surface 15 and sixth surface 16. Figure 4 In the example, there is one insulating part 2. The second surfaces 12, third surfaces 13, and fourth surfaces 14 of multiple busbars 100 can be insulated by the same insulating part 2, so that the insulating part 2 is also provided at the interval between adjacent busbars 100 in the first direction. The two ends of the insulating part 2 in the first direction can extend beyond the end faces of the two busbars 100 located on both sides. With this configuration, the creepage distance of the fifth surface 15 and sixth surface 16 of the busbar body 1 extending beyond both sides is extended, while further reducing the difficulty of setting the insulating part 2.

[0058] Optionally, when the busbar 100 is located in the middle of the photovoltaic module 200, the busbar 100 may only have an insulating part 2 on the third surface 13 and / or the fourth surface 14, so as to utilize the reflective structure 231 of the insulating part 2 to enhance the power of the photovoltaic module 200.

[0059] In a 1500V voltage system, without the use of composite material (i.e., insulation part 2) for wrapping, the creepage distance of the photovoltaic module 200 in the second direction meets the requirement of being greater than 10.4mm. Figure 5In the example, when the insulating part 2 is used to wrap the busbar body 1, if the following conditions are met: ① the thickness of the insulating part 2 covering the busbar body 1 is the same except for the first surface 11 and D1+D2+D3>300μm; ② D=D1+D2+D3, and in the second direction, the longest setting length of the insulating part 2 is d1, the minimum distance between the busbar body 1 and the battery string 201 is d2, the length of the busbar body 1 is d3, and D+d3≤d1≤D+d3+d2; thus, this scheme extends the creepage distance to a maximum of the minimum distance L1 from the edge of the insulating part 2 covering the busbar body 1 on the third surface 13 and / or the fourth surface 14 near the battery cell (or it can be the edge of the busbar body 1 other than the first surface 11) to the edge of the glass 204 (the contact point between the frame 203 and the glass 204). The path extension is achieved through the insulating part 2, which significantly improves the electrical safety performance of the photovoltaic module 200. The minimum distance between one side of the second surface 12 of the busbar body 1 and the edge of the glass 204 is L2. If other conditions remain unchanged, the extended creepage distance can accommodate [a certain amount of creepage]. (mm) 2 The area of ​​the solar cell (n is the number of solar cells in a string, l is the length of the solar cell, N is the number of solar cells in the photovoltaic module 200, and x is the area of ​​the additional solar cells that can be accommodated in the photovoltaic module 200).

[0060] For example, in the CS6.2-66TB photovoltaic module, the insulation part 2 is used to wrap the busbar body 1. The width W is 4mm, the distance d2 from the first surface 11 of the busbar body 1 to the edge of the cell is 2mm, and the original creepage distance L2 is 12.5mm. After wrapping the busbar body 1 with the insulation part 2, the creepage distance L1 is increased to 16.5mm-18.5mm, achieving an effective extension of 4mm-6mm. This is achieved while maintaining the original cell string spacing and the safety distance benchmark (12.5mm). When the creepage distance is extended by 4mm, the photovoltaic module 200 can accommodate approximately 0.3% more solar cells (based on 182mm×210mm solar cells). When the creepage distance is extended by 6mm, the cell capacity increases by approximately 0.5% (based on a 182mm × 210mm half-cell).

[0061] This technical solution extends the creepage path from the edge of the busbar body 1 to the edge of the glass 204 to the edge section of the battery string 201 to the glass 204. While ensuring electrical safety (meeting the requirement of >10.4mm for 1500V system), it significantly improves the power of the photovoltaic module 200. The insulation part 2 covers the busbar body 1 to optimize the efficiency of the photovoltaic module 200.

[0062] In summary, the photovoltaic module 200 of this application has the following technical effects: 1. By adopting the design of covering the busbar body 1 with the insulating part 2, the creepage distance between the busbar body 1 and the frame 203 is significantly extended, effectively improving the electrical safety performance of the photovoltaic module 200.

[0063] 2. The technology of the insulating part 2 covering the busbar body 1 of the present invention can adapt to a larger battery string 201 size without changing the area of ​​the photovoltaic module 200, thereby effectively improving the power output of the photovoltaic module 200 of the same area; 3. By using the reflective layer 23, the utilization rate of light is improved, the power loss of the photovoltaic module 200 is reduced, and the power efficiency of the photovoltaic module 200 is improved.

[0064] 4. The insulation part 2 of the present invention covers the busbar body 1. The technology is simple to operate, the process is controllable, it is easy to mass-produce, and it has good cost-effectiveness.

[0065] Other configurations and operations of the busbar 100 and photovoltaic module 200 according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0066] In the description of this invention, it should be understood that the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "inner", "outer", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0067] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0068] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0069] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A busbar, characterized in that, include: The busbar body has an outer surface comprising a first surface, a second surface, a third surface, a fourth surface, a fifth surface, and a sixth surface. The first surface and the second surface are opposite to each other and are adjacent to the battery cell. The third surface and the fourth surface are opposite to each other and are located on the light-receiving surface. The fifth surface and the sixth surface are opposite to each other and are respectively connected between the two ends of the first surface, the second surface, the third surface, and the fourth surface. An insulating portion that covers the second surface, and at least a portion of the third and fourth surfaces; The insulating portion also covers at least a portion of the fifth surface and the sixth surface; And / or, The insulating portion extends outward from both sides where the fifth surface and the sixth surface are located, respectively, beyond the fifth surface and the sixth surface; The insulating part includes an adhesive layer, a substrate layer and a reflective layer. The adhesive layer and the reflective layer are respectively disposed on both sides of the substrate layer in the thickness direction. The adhesive layer is connected to the outer surface of the busbar body.

2. The busbar according to claim 1, characterized in that, The insulating portion covers the third surface and the fourth surface, and the insulating portion extends beyond the third surface and the fourth surface in the direction of the battery cell.

3. The busbar according to claim 2, characterized in that, The insulating portion covers the fifth surface and the sixth surface, and extends beyond the fifth surface and the sixth surface in the direction of the battery cell; and / or, the insulating portion extends outward from both sides of the fifth surface and the sixth surface to exceed the fifth surface and the sixth surface without covering the fifth surface and the sixth surface.

4. The busbar according to claim 1, characterized in that, The reflective layer includes a first reflective portion, a second reflective portion, and a spacer portion disposed between the first reflective portion and the second reflective portion. The first reflective portion and the second reflective portion have different reflective structures. When the insulating portion covers the busbar body, the first reflective portion is disposed on the third surface of the busbar body, the second reflective portion is disposed on the fourth surface of the busbar body, and the spacer portion is disposed on the second surface. Light on the light-receiving surface is reflected by the reflective structure of the first reflective portion to the front of the adjacent battery cell, and light from the back is reflected by the reflective structure of the second reflective portion to the back of the adjacent battery cell.

5. The busbar according to claim 1, characterized in that, The reflective layer is a TiO2 high-reflection coating, a polyolefin-based reflective film, or a high-reflection fluorine coating; and / or, The substrate layer includes at least one of a polyethylene terephthalate layer, a polyolefin layer, and a silicone rubber layer.

6. The busbar according to claim 1, characterized in that, The thickness of the reflective layer is D1, wherein D1 satisfies: 10μm ≤ D1 ≤ 20μm; and / or, The thickness of the substrate layer is D2, and the width of the substrate layer is W, wherein D2 and W respectively satisfy: 300μm≤D2≤500μm, 8mm≤W≤12mm; and / or, The thickness of the adhesive layer is D3, wherein D3 satisfies: 30μm≤D3≤75μm.

7. The busbar according to claim 1, characterized in that, The insulating part further includes: A protective layer is disposed on the side of the reflective layer away from the busbar body.

8. A photovoltaic module, characterized in that, include: Multiple battery strings, wherein the multiple battery strings are connected in series by solder strips and arranged along a first direction; Multiple busbars are disposed on one side of multiple battery strings and spaced apart along the first direction. The busbars are connected to the battery strings via the solder strips. The busbars are busbars according to any one of claims 1-7.

9. The photovoltaic module according to claim 8, characterized in that, The insulating portions of the multiple busbars are provided one-to-one with the busbar body, respectively covering all surfaces of the outer side of each busbar body except for the first surface.

10. The photovoltaic module according to claim 8, characterized in that, The insulating portion of the busbar simultaneously covers the outer side of multiple busbar bodies.

11. The photovoltaic module according to claim 10, characterized in that: The insulating portion simultaneously covers the second, third, and fourth surfaces of multiple busbar bodies. For the fifth or sixth surfaces of the two outermost busbar bodies, the two ends of the insulating portion cover the outermost fifth or sixth surfaces and extend beyond the fifth or sixth surfaces in the direction of the battery cell; For the fifth and sixth surfaces of the remaining busbar bodies located between the two outermost busbar bodies, the insulating portion extends beyond the fifth and sixth surfaces in the first direction and does not cover the fifth and sixth surfaces; or, The insulating portion simultaneously covers the second, third, and fourth surfaces of the plurality of busbar bodies, and the insulating portion extends outward from both ends along the first direction beyond the fifth and sixth surfaces of each busbar body without covering the fifth and sixth surfaces.

Images