Photovoltaic welding strip and photovoltaic module

Abstract

The utility model discloses a photovoltaic welding strip and a photovoltaic module. The photovoltaic solder strip comprises a conductive substrate, an adhesion layer and a solder layer. The conductive substrate is made of a graphene material, is located in the center of the photovoltaic solder strip, and is a main conductive carrier of the photovoltaic solder strip. And the adhesion layer is made of an oxygen-free copper material, is positioned between the conductive substrate and the solder layer, and is used for strengthening the physical connection between the conductive substrate and the solder layer. And the solder layer is positioned on the outer surface of the adhesion layer and is used for realizing effective connection between the photovoltaic solder strip and the photovoltaic battery piece as well as between the photovoltaic solder strips. The graphene has excellent electrical and mechanical properties and is high in conductivity, and the conductivity of the graphene is improved instead of being reduced when the temperature rises. Therefore, the photovoltaic assembly adopting the photovoltaic solder strip not only has higher power generation efficiency, but also has lower power generation loss in a high-temperature environment, and has more excellent power generation performance in a strong light environment.

Description

Technical Field

[0001] The present application belongs to the field of photovoltaic technology, and specifically relates to photovoltaic welding ribbons and photovoltaic modules. Background Art

[0002] Photovoltaic ribbons, also known as tin-coated copper ribbons, photovoltaic connecting wires, thin copper wires, and conductive wires, primarily serve as conductors and physical connections in photovoltaic modules. They are the primary carriers for current collection and power output in photovoltaic modules, and electrical conductivity is their most critical performance indicator. Existing photovoltaic ribbons primarily include a conductive substrate and a solder layer coated on the surface of the conductive substrate. Some specialty photovoltaic ribbons, including triangular conductive wires and black ribbons, have reflective layers and black coatings in addition to the solder layer. The conductive substrate is primarily made of oxygen-free copper and is the primary conductive component of the photovoltaic ribbon. The solder layer serves primarily as a connecting material for achieving effective connections between the photovoltaic ribbon and photovoltaic cells, and between the photovoltaic ribbons themselves. The reflective layer and black coating are primarily applied to the surface of the solder layer or directly onto the conductive substrate, providing a reflective and aesthetically pleasing finish.

[0003] Currently, the conductive substrate of photovoltaic ribbons is primarily made of traditional metal materials such as oxygen-free copper. This has limited room for improvement in conductivity, which, to a certain extent, limits further improvements in the power generation efficiency of photovoltaic modules. Furthermore, the conductivity of traditional metal materials decreases significantly with increasing temperature. This means that under strong sunlight, during periods when photovoltaic cells generate the highest power, the conductivity of the photovoltaic ribbon may be at its worst due to the relatively high temperature of the photovoltaic module. This results in very high power losses in conventional photovoltaic modules under strong sunlight. While there are photovoltaic ribbon technologies that use graphene or graphene-composite copper as the conductive substrate, these technologies are difficult to promote and apply due to complex production processes, low manufacturability, or limited performance improvements despite high prices. Summary of the Invention

[0004] The purpose of this application is to provide a photovoltaic ribbon and photovoltaic module to overcome the above-mentioned deficiencies of the prior art. In order to solve the above problems, this application is implemented as follows:

[0005] In a first aspect, the present application provides a photovoltaic ribbon comprising a conductive substrate, an adhesive layer, and a solder layer. The conductive substrate is located at the center of the ribbon and primarily serves to conduct electricity and provide a physical connection. The adhesive layer is located between the conductive substrate and the solder layer and primarily serves to strengthen the physical connection between the conductive substrate and the solder layer. The solder layer is located on the outside of the adhesive layer and primarily serves as a connecting material to achieve effective connections between the ribbon and photovoltaic cells, and between the ribbons.

[0006] Furthermore, the conductive substrate is made of graphene.

[0007] Compared to existing technologies, graphene possesses superior mechanical and electrical properties. Its tensile strength and electrical conductivity are far superior to the oxygen-free copper used in current photovoltaic ribbon conductive substrates. Furthermore, its conductivity improves with increasing temperature. Therefore, these photovoltaic ribbons not only offer enhanced conductivity, improving the power generation efficiency of photovoltaic modules, but also effectively address the high power generation losses of photovoltaic modules in strong sunlight environments, enabling them to achieve even better power generation performance in these environments.

[0008] Furthermore, the adhesion layer is made of oxygen-free copper.

[0009] Compared to existing technologies, oxygen-free copper (OFC) offers superior electrical conductivity and excellent affinity with graphene and tin, a soldering material widely used in photovoltaic ribbons. Using OFC as the adhesion layer not only reduces the production difficulty and cost of the photovoltaic ribbon, but also ensures a good physical connection between the conductive substrate, adhesion layer, and solder layer, resulting in excellent mechanical and electrical properties.

[0010] Furthermore, the cross-section of the conductive substrate as a whole or in sections can be circular, elliptical, rectangular, square, triangular or trapezoidal, so that photovoltaic welding strips with circular, elliptical, rectangular, square, triangular or trapezoidal shapes as a whole or in sections can be prepared.

[0011] By adopting the above preferred solution, photovoltaic ribbons of different shapes can be prepared, thereby taking into account the different requirements of different technical solutions for photovoltaic ribbon welding, conductive area and reflective performance.

[0012] In a second aspect, the present application proposes a photovoltaic module comprising a cell string, a film, glass, a frame, etc. The cell string is composed of two or more photovoltaic cells connected using the photovoltaic ribbon as described above, the cell strings are connected in series or in parallel, and then the cell strings are covered with a film, glass, etc. and laminated, and then a frame is installed around them, thus forming the photovoltaic module.

[0013] Compared with the existing technology, this application has the following obvious advantages:

[0014] 1. Improve the conductivity of photovoltaic ribbons and the power generation efficiency of photovoltaic modules;

[0015] 2. It solves the technical problem that the electrical conductivity of photovoltaic welding ribbons decreases with increasing temperature, resulting in higher power generation losses of photovoltaic modules in strong light environments, so that photovoltaic modules have better power generation performance in strong light environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To more clearly illustrate the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0017] Figure 1 This is a cross-sectional view of an embodiment of a photovoltaic welding ribbon of the present application;

[0018] Figure 2 It is a structural schematic diagram of a photovoltaic module embodiment of the present application.

[0019] The parts in the figure are: 1. Photovoltaic welding ribbon, 2. Solder layer, 3. Adhesion layer, 4. Conductive substrate, 5. Photovoltaic cell, 6. Photovoltaic cell string, 7. Frame, 8. Photovoltaic module. DETAILED DESCRIPTION

[0020] The specific implementation of this application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0021] exist Figure 1 In the illustrated embodiment of the photovoltaic ribbon, the ribbon is a round-wire ribbon comprising a conductive substrate 4, an adhesive layer 3, and a solder layer 2. The conductive substrate 4 is a graphene wire with a diameter of 0.08 mm to 0.28 mm, located at the center of the ribbon. The conductive substrate 4 is coated with a 0.02 mm thick oxygen-free copper adhesive layer 3. Together, the conductive substrate 4 and adhesive layer 3 form a copper-clad graphene body with a good physical connection. The adhesive layer 3 is coated with a 0.015 mm thick tin-lead alloy solder layer 2. Because graphene possesses excellent electrical and mechanical properties, the ribbon exhibits higher electrical conductivity and tensile strength than conventional oxygen-free copper conductive substrates. Furthermore, its electrical conductivity increases with temperature, resulting in superior power generation performance for photovoltaic modules under strong sunlight. The oxygen-free copper adhesion layer 3 has good affinity with the graphene conductive substrate 4 and the tin-lead alloy solder layer 2, providing a good physical connection between the conductive substrate 4, the adhesion layer 3, and the solder layer 2, thereby providing the photovoltaic ribbon with good mechanical and electrical properties. The solder layer 2 can achieve effective connection between the photovoltaic ribbon and the photovoltaic cells, and between the photovoltaic ribbons.

[0022] exist Figure 2In the photovoltaic module embodiment shown, two or more photovoltaic cells 5 are connected using the photovoltaic welding ribbon 1 proposed in this application to form a photovoltaic cell string 6. Multiple photovoltaic cell strings 6 are connected in series or parallel, and then laminated with adhesive film, glass, etc., and then a frame 7 is installed around them to form a photovoltaic module 8.

Claims

1. A photovoltaic welding ribbon, characterized in that: The invention comprises a conductive substrate (4), an attachment layer (3) and a solder layer (2), wherein the conductive substrate (4) is made of graphene and is located at the center of the photovoltaic soldering strip, the attachment layer (3) is made of oxygen-free copper and is located between the conductive substrate (4) and the solder layer (2), and the solder layer (2) is located on the surface of the attachment layer (3).

2. A photovoltaic welding ribbon according to claim 1, characterized in that: The cross-section of the conductive substrate (4) as a whole or in sections is circular, elliptical, rectangular, square, triangular or trapezoidal.

3. A photovoltaic module comprising a cell string (6), a film, glass, and a frame (7), characterized in that: The cell string (6) comprises two or more photovoltaic cells (5) and a photovoltaic welding ribbon (1) according to any one of claims 1 to 2, wherein the two or more photovoltaic cells (5) are connected by the photovoltaic welding ribbon (1) to form a photovoltaic cell string (6).

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