Conductive structure for photovoltaic module and photovoltaic module

Abstract

The present invention discloses a conductive structure for a photovoltaic module and a photovoltaic module. The conductive structure includes a conductive mesh; the conductive mesh includes at least two conductive wires and at least one connecting wire for connecting the conductive wires to form a mesh structure; the conductive wires are parallel to each other; the connecting wire connects the conductive wires to form a mesh structure, and the parallel conductive wires are directly woven into a mesh to form a conductive mesh combined with a fine grid. The extremely fine conductive wires can be stably connected to the fine grid without a polymer film, thereby effectively reducing production costs while maintaining a stable connection.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic modules, and in particular to a conductive structure for photovoltaic modules and a photovoltaic module. Background Art

[0002] After years of rapid development in photovoltaic cell technology, the conversion efficiency of the current mainstream PERC cell has approached its theoretical limit. High hopes are placed on the next generation of high-efficiency cells with heterojunctions. However, heterojunction technology is still far from mature, and the production cost is extremely high, significantly lower than the production cost of PERC cells. Therefore, cost reduction is a prerequisite for heterojunction cells to become mainstream in the future. In heterojunction cell production, silver paste is required as solder joints on the cell. Silver is a precious metal and is expensive, so the cost of silver paste accounts for a significant proportion of the cell cost. To reduce the high cost of silver paste, a technical method is currently being used to eliminate solder joints. This involves welding the conductive ribbon to the fine grid on the cell. However, due to the narrow width of the ribbon and the fine grid, the tension after welding is very small, making it easy for external forces to separate during subsequent handling and movement. In addition, the ribbons are extremely thin, and multiple ribbons welded one by one to the fine grid are prone to displacement.

[0003] To solve the above problems, the method currently adopted is: first pull out multiple parallel welding ribbons and compound them onto a polymer film under certain process conditions, and then place the polymer film compounded with welding ribbons and battery cells in sequence through equipment to form a battery string, and then use automated equipment to stack multiple battery strings into a component, and finally use conventional lamination processes to laminate the welding ribbons on the polymer film and connect the fine grid to form an ohmic contact, so that the welding ribbon is stably connected to the fine grid at one time and is not easy to shift or misalign, and the component is packaged when the welding ribbon is connected to the fine grid, which can provide good protection for the welding ribbon and fine grid inside the component. However, this method has the following problems: 1. When using polymer film composite welding ribbons, the film material cost of the polymer film is relatively high, and the reliability of the polymer film and its compatibility with other battery component materials need to be experimentally verified first during production, resulting in a long production cycle; 2. The welding ribbon and polymer film composite process requires the introduction of coating equipment, which increases equipment investment. Summary of the Invention

[0004] The purpose of the present invention is to provide a conductive structure for a photovoltaic module and a photovoltaic module.

[0005] The technical solution of the present invention is as follows: in a first aspect, a conductive structure for a photovoltaic module is provided, comprising a conductive mesh;

[0006] The conductive mesh includes at least two conductive wires and at least one connecting wire for connecting the conductive wires to form a mesh structure; the conductive wires are parallel to each other.

[0007] In a preferred embodiment, the connecting wire intersects with the conductive wire and two adjacent conductive wires are connected to at least two sides of one connecting wire;

[0008] and / or, at least part of the connecting filaments intersect with the conductive filaments at an angle;

[0009] and / or, both sides of the conductive thread are connected to the connecting thread;

[0010] and / or, the connecting wire is at least partially ring-shaped;

[0011] and / or, the connecting wire is at least partially sine-wave shaped;

[0012] And / or, the connecting wire includes a first connecting wire for connecting all the conductive wires;

[0013] And / or, the connecting wires include second connecting wires used to connect some of the conductive wires and staggered to form a mesh structure.

[0014] In a preferred embodiment, the conductive wire includes one or more of copper wire, aluminum wire, silver wire, tin wire, copper alloy wire, aluminum alloy wire, silver alloy wire, and tin alloy wire; and / or the cross-section of the conductive wire is a triangle with a base portion extending outward on the bottom side, and one or more of a circle, a semicircle, an ellipse, a triangle, and a quadrilateral; and / or the diameter of the conductive wire is 0.005 mm to 0.25 mm.

[0015] In a preferred embodiment, the conductive mesh includes a plurality of conductive mesh units, the cross-sections of the conductive wires at both sides of the conductive mesh unit are triangular, and the cross-sections of the conductive wires at the middle of the conductive mesh unit are circular.

[0016] In a preferred embodiment, the conductive mesh has a mesh size of 50-1000 meshes; and / or the length of the conductive mesh in a direction perpendicular to the conductive filaments is 100-200 mm.

[0017] In a preferred embodiment, the conductive mesh includes a first conductive mesh unit and a second conductive mesh unit, and the mesh size of the first conductive mesh unit is smaller than the mesh size of the second conductive mesh unit.

[0018] In a preferred embodiment, the conductive wire or the conductive mesh is coated with a conductive layer.

[0019] In a preferred embodiment, the conductive layer includes a metal layer; and / or a non-metal layer containing conductive particles; and / or the thickness of the conductive layer is 2 μm to 30 μm.

[0020] In a preferred embodiment, the metal layer includes one or more of a tin layer, a lead layer, a bismuth layer, a silver layer, an indium layer, a copper layer, a nickel layer, and an antimony layer; and / or the metal layer includes an alloy layer containing at least two of tin, lead, bismuth, silver, indium, copper, nickel, and antimony;

[0021] The non-metallic layer containing conductive particles includes a conductive adhesive layer containing silver particles and / or copper particles.

[0022] In a second aspect, a photovoltaic module is provided, comprising a conductive structure for a photovoltaic module as described in any one of the first aspects.

[0023] Compared with the prior art, the advantages of the present invention are: providing a conductive structure and a photovoltaic module for a photovoltaic module, the conductive structure includes a conductive mesh; the conductive mesh includes at least two conductive wires and connecting wires for connecting the conductive wires to form a mesh structure; the conductive wires are parallel to each other; the connecting wires connect the conductive wires to form a mesh structure, and the parallel conductive wires are directly woven into a mesh to form a conductive mesh combined with a fine grid, and the extremely fine conductive wires can be stably connected to the fine grid without the need for a polymer film, which effectively reduces the production cost while stabilizing the connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A first schematic diagram of a conductive structure for a photovoltaic module provided in Example 1 of the present invention;

[0026] Figure 2 A second schematic diagram of a conductive structure for a photovoltaic module provided in Example 1 of the present invention;

[0027] Figure 3 This is a first schematic diagram of a conductive structure for a photovoltaic module provided in Example 2 of the present invention;

[0028] Figure 4 A second schematic diagram of a conductive structure for a photovoltaic module provided by Embodiment 2 of the present invention;

[0029] Figure 5 A first schematic diagram of a conductive structure for a photovoltaic module provided by Example 3 of the present invention;

[0030] Figure 6 A second schematic diagram of a conductive structure for a photovoltaic module provided by Example 3 of the present invention;

[0031] Figure 7 A schematic diagram of a conductive structure for a photovoltaic module provided in Example 4 of the present invention;

[0032] Figure 8 A schematic diagram of a conductive structure for a photovoltaic module provided in Example 5 of the present invention;

[0033] Figure 9 A schematic diagram of a conductive structure for a photovoltaic module provided in Example 6 of the present invention;

[0034] Figure 10 A schematic diagram of a conductive structure for a photovoltaic module provided in Example 7 of the present invention;

[0035] Figure 11 A schematic diagram of a conductive structure for a photovoltaic module provided in Example 8 of the present invention;

[0036] Wherein: 100, conductive mesh; 1, conductive wire; 11, first conductive segment; 12, second conductive segment; 2, connecting wire. DETAILED DESCRIPTION

[0037] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0038] As described in the background technology, a plurality of mutually parallel solder strips are first compounded onto a polymer film, and then the polymer film compounded with the solder strips and the battery cells are arranged according to preset rules and laminated, so that the polymer film covers and connects to the surface of the battery cell, so that the solder strips on the polymer film are connected to the fine grid on the surface of the battery cell to form an ohmic contact. However, the polymer film is expensive and needs to undergo a long period of testing before use. In addition, special compounding equipment needs to be added to compound the solder strips with the polymer film, which is expensive and time-consuming.

[0039] Example 1: This example provides a conductive structure for a photovoltaic module, referring to Figure 1 As shown, it includes a conductive mesh 100; the conductive mesh 100 includes at least two conductive wires 1 and at least one connecting wire 2 for connecting the conductive wires 1 to form a mesh structure; the conductive wires 1 are parallel to each other.

[0040] Specifically, in this embodiment, the spacing between the conductive threads 1 can be equal or unequal. In this embodiment, it is preferred that the spacing between the conductive threads 1 is equal so that the current is more uniform.

[0041] In this embodiment, the connecting wires 2 and the conductive wires 1 are preferably arranged perpendicular to each other. Each connecting wire 2 spans all the conductive wires 1, and the spacing between the connecting wires 2 can be equal or as Figure 2 The shown values ​​are not equal, and this embodiment does not make any specific limitation on this.

[0042] In a preferred embodiment, the connecting wire 2 intersects with the conductive wire 1 and two adjacent conductive wires 1 are connected to both sides of the connecting wire 2, that is, they are woven, and the structure is more stable. Even if the connection point between the connecting wire 2 and the conductive wire 1 falls off, it is not easy to loosen.

[0043] In a preferred embodiment, the conductive wire 1 includes one or more of copper wire, aluminum wire, silver wire, tin wire, copper alloy wire, aluminum alloy wire, silver alloy wire, and tin alloy wire; and / or the cross-section of the conductive wire 1 is a triangle with a base portion extending outward on the bottom side, and one or more of a circle, a semicircle, an ellipse, a triangle, and a quadrilateral.

[0044] In a preferred embodiment, the diameter of the conductive thread 1 is 0.005 mm to 0.25 mm.

[0045] In a preferred embodiment, the conductive wire 1 or the entire conductive mesh 100 is coated with a conductive layer (not shown).

[0046] In a preferred embodiment, the conductive layer includes a metal layer and / or a non-metal layer containing conductive particles; and / or the thickness of the conductive layer is 2 μm to 30 μm.

[0047] More preferably, the metal layer includes one or more of a tin layer, a lead layer, a bismuth layer, a silver layer, an indium layer, a copper layer, a nickel layer, and an antimony layer, and / or the metal layer includes an alloy layer containing at least two of tin, lead, bismuth, silver, indium, copper, nickel, and antimony, which makes welding with the battery cell easier and improves the welding effect. Different conductive filaments 1 in the conductive mesh 100 can be coated with the same conductive layer or different conductive layers, and even different conductive layers can be coated in sections on the same conductive filament 1, which is not limited in this embodiment. The non-metallic layer containing conductive particles includes a conductive adhesive layer containing silver particles and / or copper particles, which conducts electricity while further reducing stress after connection with the battery cell.

[0048] In a preferred embodiment, the conductive mesh 100 includes a plurality of conductive mesh units, each of which covers a battery string. The conductive filaments located on both sides of the conductive mesh unit have a triangular cross-section with an outwardly extending base portion and / or a triangle on the bottom edge, and the conductive filaments located in the middle of the conductive mesh unit have a circular cross-section. That is, the conductive filaments located in the middle of the battery cell have a circular cross-section, while the conductive filaments located at the edge of the battery cell have a triangular cross-section with an outwardly extending base portion and / or a triangle on the bottom edge. Because the current in the middle of the battery cell is generally larger, and the conductive filaments with a triangular cross-section or a triangular cross-section with an outwardly extending base portion on the bottom edge are more conducive to light reflection, placing the conductive filaments with a triangular cross-section and / or a triangular cross-section with an outwardly extending base portion on the bottom edge at the edge of the battery cell can make the current distribution of the entire battery more uniform, which is beneficial to improving the battery power.

[0049] In a preferred embodiment, the conductive mesh 100 has a mesh size of 50-1000; and / or the length of the conductive mesh 100 in a direction perpendicular to the conductive filaments 1 is 100-200 mm. That is, the conductive mesh 100 may have a mesh size of 50-100 and a length perpendicular to the conductive filaments 1 of 100-200 mm, or the conductive mesh 100 may have a mesh size of 50-100 and a length perpendicular to the conductive filaments 1 outside the range of 100-200 mm. This embodiment does not specifically limit this.

[0050] The connecting wire 2 is preferably a metal connecting wire, which is easier to form a mesh. More preferably, the connecting wire 2 is one or more of copper wire, aluminum wire, gold wire, silver wire, and tin wire. It can also be a metal alloy wire, and the metal alloy wire contains an alloy composed of any two or more of copper, aluminum, gold, silver, and tin. The connecting wire 2 can have the same cross-section as the conductive wire 1, or it can have a different cross-section. In this embodiment, the connecting wire 2 is preferably the same as the conductive wire 1 in cross-section. More preferably, the cross-sectional dimensions of the connecting wire 2 and the conductive wire 1 are also the same, which is more convenient for weaving into a mesh. Exemplarily, the connecting wire 2 and the conductive wire 1 are both metal wires with circular cross-sections, and the diameters of the connecting wire 2 and the conductive wire 1 are equal.

[0051] The surface of the connecting wire 2 can also be coated with a reflective layer to improve the reflective efficiency. More preferably, the reflective layer has a thickness of 5-20 μm, effectively compensating for the power loss caused by the connecting wire 2 itself blocking light. The surface of the connecting wire 2 can also be coated with a coating of the same material as the surface of the conductive wire 1 to facilitate welding or bonding with the conductive wire 1 to form a node, thereby enhancing the strength and stability of the conductive network.

[0052] The present embodiment provides a conductive structure and a photovoltaic module for a photovoltaic module, wherein the conductive structure includes a conductive mesh; the conductive mesh includes at least two conductive wires and connecting wires for connecting the conductive wires to form a mesh structure; the conductive wires are parallel to each other; the connecting wires connect the conductive wires to form a mesh structure, and the parallel conductive wires are directly woven into a mesh to form a conductive mesh combined with a fine grid. The extremely fine conductive wires can be stably connected to the fine grid without the need for a polymer film, thereby effectively reducing production costs while maintaining a stable connection.

[0053] Example 2: This example provides a conductive structure for a photovoltaic module. The difference from Example 1 is that in this example, at least half of the connecting wire 2 and the conductive wire 1 are arranged to intersect obliquely. Figure 4 As shown, in this embodiment, the spacing between the connecting wires 2 can be equal or as Figure 4 As shown, the spacing between the connecting wires 2 is not equal. Figure 3 and Figure 4 As shown, all the connecting wires 2 are arranged to intersect with the conductive wires 1 at an angle, or some of the connecting wires 2 may intersect with the conductive wires 1 at an angle, while other connecting wires 2 may intersect with the conductive wires 1 at a right angle.

[0054] In addition, in this embodiment, there is no limitation on whether the spacing between the conductive threads 1 is equal. Two adjacent conductive threads 1 can be connected to the same side of the same connecting thread 22 or to different sides of the same connecting thread 22.

[0055] Example 3: This example provides a conductive structure for a photovoltaic module. The difference from Example 1 is that the spacing between the conductive wires 1 is not equal. In this example, the connecting wires 2 can be as follows: Figure 5 As shown, it is arranged vertically with the conductive wire 1, or it can be as shown Figure 6 While the connecting threads 2 are arranged non-perpendicularly to the conductive threads 1 as shown, some connecting threads 2 may intersect the conductive threads 1 at an angle, while others may intersect the conductive threads 1 at a perpendicular angle. This embodiment does not specifically limit the spacing between the connecting threads 2. Two adjacent conductive threads 1 may be connected to the same side of the same connecting thread 22, or to different sides of the same connecting thread 22.

[0056] Example 4: Reference Figure 7As shown, this embodiment provides a conductive structure for a photovoltaic module, which differs from the embodiment 1 in that the connecting wires 2 include a first connecting wire 21 for connecting all the conductive wires 1 and a second connecting wire 22 for connecting part of the conductive wires 1 and staggered to form a mesh structure. The second connecting wires 22 can be of equal length or different lengths, and can be staggered with the first connecting wires 21 one by one, or arranged irregularly, which is not limited in this embodiment. In addition, in this embodiment, the conductive wires 1 can be arranged with equal spacing or with unequal spacing; the conductive wire 1 can be perpendicular to the first connecting wire 21, or can intersect non-perpendicularly; the conductive wire 1 can be perpendicular to the second connecting wire 22, or can intersect non-perpendicularly. Two adjacent conductive wires 1 can be connected to the same side of the same connecting wire 22, or can be connected to different sides of the same connecting wire 22.

[0057] Example 5: This example provides a conductive structure for a photovoltaic module. The difference from Example 1 is that the connecting wire 2 includes a second connecting wire 22 for connecting part of the conductive wire 1 and staggered to form a mesh structure. The second connecting wire 22 can be arranged regularly, for example, refer to Figure 8 As shown, the second connecting threads 22 are periodically arranged on the conductive threads 1 in a sine wave pattern. The second connecting threads 22 can also be arranged irregularly on the conductive threads 1. Furthermore, in this embodiment, the conductive threads 1 can be arranged at equal or unequal intervals; the conductive threads 1 can be perpendicular to the first connecting threads 21 or intersecting at a non-perpendicular angle; and the conductive threads 1 can be perpendicular to the second connecting threads 22 or intersecting at a non-perpendicular angle. Two adjacent conductive threads 1 can be connected to the same side of the same connecting thread 22 or to different sides.

[0058] Example 6: Reference Figure 9 As shown, the conductive structure for a photovoltaic module provided in this embodiment differs from that in Example 1 in that the conductive mesh 100 includes a first conductive mesh unit and a second conductive mesh unit, with the mesh size of the first conductive mesh unit being smaller than that of the second conductive mesh unit. Specifically, during use, the first conductive mesh unit is attached to the back of the cell, with a tighter mesh, improving the connection strength between the conductive mesh and the cell. The second conductive mesh unit is attached to the front of the cell, with a sparser mesh, reducing the degree of light blocking. In this embodiment, there are no restrictions on whether the spacing of the conductive threads 1 is equal, whether the conductive threads 1 are perpendicular to the connecting threads 2, or whether the length of the connecting threads 2 and whether they are arranged equidistantly.

[0059] Example 7: Reference Figure 10 As shown, the conductive structure for a photovoltaic module provided in this embodiment is different from that in embodiment 1 in that: in this embodiment, the connecting wires 2 are attached to the same side of the conductive mesh 100 .

[0060] Example 8: Reference Figure 11 As shown, the conductive structure for a photovoltaic module provided in this embodiment differs from the above-described embodiments in that: in this embodiment, the connecting wires 2 are at least partially ring-shaped. Preferably, each connecting wire 2 is curved in a sinusoidal wave shape and interconnected to form adjacent rings. Of course, the connecting wires 2 can also be curved in a sinusoidal wave shape without interlacing the sinusoidal waves to form a ring, or connected in other curved forms to form a ring, which is not limited in this embodiment.

[0061] Example 8: This example provides a photovoltaic module, including a conductive structure for a photovoltaic module as provided in any of Examples 1 to 8.

[0062] It should be noted that the photovoltaic module provided in this embodiment and the conductive structure for a photovoltaic module provided in Examples 1 to 7 have the same concept, and the beneficial effects thereof can be seen in the above-mentioned embodiments and will not be repeated here.

[0063] The various embodiments in this specification are described in a progressive manner. Similar portions between the various embodiments can be referenced to each other. Each embodiment focuses on the differences between the other embodiments. In particular, since system or system embodiments are generally similar to method embodiments, their descriptions are relatively simplified. For relevant portions, reference can be made to the descriptions of the method embodiments.

[0064] Although the preferred embodiment of the present invention has been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiment and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0065] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the present invention and implement it accordingly. They are not intended to limit the scope of protection of the present invention. Any modifications made within the spirit of the main technical solution of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A conductive structure for a photovoltaic module, characterized in that: including a conductive mesh; The conductive mesh comprises at least two conductive wires and at least one connecting wire for connecting the conductive wires to form a mesh structure; the conductive wires are parallel to each other; The conductive mesh includes a first conductive mesh unit and a second conductive mesh unit, wherein the mesh size of the first conductive mesh unit is smaller than the mesh size of the second conductive mesh unit; and the connecting wire is a metal connecting wire.

2. The conductive structure for a photovoltaic module according to claim 1, characterized in that: The connecting wire intersects with the conductive wire and two adjacent conductive wires are connected to at least two sides of one connecting wire; and / or, at least part of the connecting filaments intersect with the conductive filaments at an angle; and / or, both sides of the conductive thread are connected to the connecting thread; and / or, the connecting wire is at least partially ring-shaped; and / or, the connecting wire is at least partially sine-wave shaped; And / or, the connecting wire includes a first connecting wire for connecting all the conductive wires; And / or, the connecting wires include second connecting wires used to connect some of the conductive wires and staggered to form a mesh structure.

3. The conductive structure for a photovoltaic module according to claim 1, characterized in that: The conductive wire includes one or more of copper wire, aluminum wire, silver wire, tin wire, copper alloy wire, aluminum alloy wire, silver alloy wire, and tin alloy wire; and / or the cross-section of the conductive wire is one or more of circular, semicircular, elliptical, triangular, and quadrilateral; and / or the diameter of the conductive wire is 0.005mm to 0.25mm.

4. The conductive structure for a photovoltaic module according to claim 1, characterized in that: The cross-sections of the conductive wires at both sides of the conductive mesh unit are triangular, and the cross-sections of the conductive wires at the middle of the conductive mesh unit are circular.

5. The conductive structure for a photovoltaic module according to claim 1, characterized in that: The conductive mesh has a mesh size of 50-1000 meshes; and / or the length of the conductive mesh in a direction perpendicular to the conductive filaments is 100-200 mm.

6. The conductive structure for a photovoltaic module according to claim 1, characterized in that: The conductive wire or the conductive mesh is coated with a conductive layer.

7. The conductive structure for a photovoltaic module according to claim 6, characterized in that: The conductive layer includes a metal layer; and / or the conductive layer includes a non-metal layer containing conductive particles; and / or the conductive layer has a thickness of 2 μm to 30 μm.

8. The conductive structure for a photovoltaic module according to claim 7, characterized in that: The metal layer includes one or more of a tin layer, a lead layer, a bismuth layer, a silver layer, an indium layer, a copper layer, a nickel layer, and an antimony layer; and / or the metal layer includes an alloy layer containing at least two of tin, lead, bismuth, silver, indium, copper, nickel, and antimony; The non-metallic layer containing conductive particles includes a conductive adhesive layer containing silver particles and / or copper particles.

9. A photovoltaic module, characterized in that: The present invention comprises a conductive structure for a photovoltaic module according to any one of claims 1 to 8.

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