Solder strip and photovoltaic module

Abstract

The utility model relates to the field of photovoltaic technology, and discloses a solder strip and a photovoltaic assembly. The solder strip comprises a base material layer, a solder layer and a black coating, the solder layer is annularly arranged on the outer side of the base material layer, the solder layer comprises a plurality of first protruding parts and first concave parts formed between the adjacent first protruding parts, and the first protruding parts are formed by protruding from the outer surface of the solder layer back to the base material layer; the black coating is annularly arranged on the outer side of the solder layer, the black coating comprises a plurality of second protruding parts and second concave parts formed between the adjacent second protruding parts, and the second protruding parts are formed by protruding from the inner surface of the black coating to the base material layer; the first protruding part is matched with the second concave part, and the second protruding part is matched with the first concave part, so that the connection strength between the solder layer and the black coating is better, the adhesive force of the black coating is improved, and the black coating is not prone to falling off.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaics, in particular to a welding strip and a photovoltaic component. Background Art

[0002] Photovoltaic modules are used to convert solar energy into electrical energy. A photovoltaic module includes multiple photovoltaic cells. Two adjacent photovoltaic cells are connected in series through welding ribbons. The welding ribbons are connected to the main grid of the battery to collect and transmit current.

[0003] Black round wire welding ribbon of related technology: the surface layer is organic black coating, and the manufacturing process is to spray black organic coating on the surface of silver round wire welding ribbon, and the black organic coating is mainly composed of flux and carbon black; after the welding ribbon is welded by high-temperature heating of the welding machine, the black coating is easy to fall off, because the flux contains acid activators, which are affected by carbon black after welding and cannot be effectively volatilized. After lamination, it is easy to react with the adhesive film, which affects the reliability of the component. Utility Model Content

[0004] Based on this, the utility model provides a welding strip and a photovoltaic module, which can improve the adhesion of the black coating.

[0005] In order to solve the above technical problems, a technical solution adopted by the utility model is to provide a welding strip, including:

[0006] substrate layer;

[0007] A solder layer, the solder layer is disposed on the outer side of the base material layer, the solder layer comprises a plurality of first protrusions and first recessed portions formed between adjacent first protrusions, the first protrusions are formed by protruding from the outer surface of the solder layer away from the base material layer;

[0008] A black coating layer, the black coating layer is disposed around the outer side of the solder layer, the black coating layer comprises a plurality of second protrusions and second recessed portions formed between adjacent second protrusions, the second protrusions are formed by protruding from the inner surface of the black coating layer toward the base material layer;

[0009] The first protrusion matches with the second recess, and the second protrusion matches with the first recess.

[0010] According to an embodiment of the present invention, the substrate layer is in a strip-shaped structure and has a circular cross-section, and the diameter of the substrate layer is 0.18 mm-0.35 mm.

[0011] According to an embodiment of the present invention, the cross-sectional shape of the first protrusion and / or the first recess is a triangle, a rectangle, a trapezoid or a semicircle.

[0012] According to an embodiment of the present invention, the thickness of the first protrusion is 15 μm-40 μm, and the thickness of the first protrusion is the distance between the highest point of the first protrusion and the outer surface of the substrate layer.

[0013] According to an embodiment of the present invention, the thickness of the first recessed portion is 0-15 μm, and the thickness of the first recessed portion is the distance between the lowest concave point of the first recessed portion and the outer surface of the substrate layer.

[0014] According to an embodiment of the present invention, the thickness of the second protrusion is 25 μm-40 μm, and the thickness of the second protrusion is the distance between the highest protrusion of the second protrusion and the inner surface of the black coating.

[0015] According to an embodiment of the present invention, the thickness of the second recessed portion is 0-5 μm, and the thickness of the second recessed portion is the distance between the lowest concave point of the second recessed portion and the inner surface of the black coating.

[0016] According to an embodiment of the present invention, the number of the first protrusions is 20-300.

[0017] According to an embodiment of the present invention, the black coating is a black metal oxide layer or a black metal alloy layer, and the melting point of the black coating is higher than the melting point of the solder layer.

[0018] In order to solve the above technical problems, another technical solution adopted by the present invention is to provide a photovoltaic module, including: the welding ribbon and battery cells, wherein the welding ribbon is connected to the battery cells.

[0019] The beneficial effects of the utility model are as follows: a solder strip comprises: a substrate layer, a solder layer and a black coating; the solder layer is arranged on the outside of the substrate layer, the solder layer comprises a plurality of first protrusions and a first recessed portion formed between adjacent first protrusions, the first protrusion being formed by protruding from the outer surface of the solder layer away from the substrate layer; the black coating is arranged on the outside of the solder layer, the black coating comprises a plurality of second protrusions and a second recessed portion formed between adjacent second protrusions, the second protrusion being formed by protruding from the inner surface of the black coating toward the substrate layer; the first protrusion cooperates with the second recessed portion, and the second protrusion cooperates with the first recessed portion, so that the connection strength between the solder layer and the black coating is better, thereby improving the adhesion of the black coating and preventing it from falling off easily. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of a welding strip according to an embodiment of the utility model;

[0021] Figure 2 It is a schematic structural diagram of a welding strip of another embodiment of the utility model;

[0022] Figure 3 It is a schematic structural diagram of a welding strip of another embodiment of the utility model;

[0023] Figure 4 It is a schematic structural diagram of a welding strip of another embodiment of the utility model;

[0024] Figure 5 It is a schematic structural diagram of a welding strip of another embodiment of the utility model;

[0025] Figure 6 It is a structural schematic diagram of a welding strip according to another embodiment of the utility model.

[0026] The meanings of the symbols in the accompanying drawings are:

[0027] 100-solder strip; 10-base material layer; 20-solder layer; 30-black coating; 21-first protrusion; 22-first recess; 31-second protrusion; 32-second recess; D-diameter of base material layer; d1-thickness of first protrusion; d2-thickness of first recess; d3-thickness of second protrusion; d4-thickness of second recess. DETAILED DESCRIPTION

[0028] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0029] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0031] Figure 1 Schematic diagram of the structure of the welding strip of one embodiment of the utility model. Figure 1As shown, the solder strip 100 includes a base material layer 10, a solder layer 20 and a black coating layer 30. The solder layer 20 is disposed on the outside of the base material layer 10, and the black coating layer 30 is disposed on the outside of the solder layer 20.

[0032] The solder layer 20 includes a plurality of first protrusions 21 and first recesses 22 formed between adjacent first protrusions 21 . The first protrusions 21 are formed by protruding from the outer surface of the solder layer 20 away from the substrate layer 10 .

[0033] The black coating layer 30 includes a plurality of second protrusions 31 and second recesses 32 formed between adjacent second protrusions 31 . The second protrusions 31 are formed to protrude from the inner surface of the black coating layer 30 toward the substrate layer 10 .

[0034] The first protrusion 21 matches with the second recess 32, and the second protrusion 31 matches with the first recess 22. It can be understood that the first protrusion 21 matches with the second recess 32 in shape and size, and the second protrusion 31 matches with the first recess 22 in shape and size.

[0035] The solder strip 100 of this embodiment improves the connection strength between the solder layer 20 and the black coating 30 through the concave-convex fit between the first protrusion 21 and the second recessed portion 32 and the concave-convex fit between the second protrusion 31 and the first recessed portion 22, thereby improving the adhesion of the black coating 30 and preventing it from falling off.

[0036] See also Figure 1 The substrate layer 10 has a strip-shaped structure and a circular cross section. The diameter D of the substrate layer 10 is 0.18 mm-0.35 mm, preferably 0.22 mm-0.30 mm.

[0037] In some embodiments, the number of the first protrusions 21 is 20-300, and the first recesses 22 are formed by adjacent first protrusions 21, so the number of the first recesses 22 is the same as the number of the first protrusions 21. The number of the second recesses 32 is set corresponding to the number of the first protrusions 21, and the number of the second protrusions 31 is set corresponding to the number of the first recesses 22. The number of the first protrusions 21 can be adjusted according to actual applications, for example, it can be adjusted according to the diameter of the substrate layer 10, and the specific number is not specifically limited here.

[0038] In some embodiments, the cross-sectional shape of the first protrusion 21 and / or the first recess 22 is a triangle, a rectangle, a trapezoid or a semicircle. It can be understood that the cross-sectional shapes of the first protrusion 21 and the first recess 22 can be the same or different, and the cross-sectional shapes of the second protrusion 31 and the second recess 32 can be the same or different, as long as the shapes and sizes of the first protrusion 21 and the second recess 32 are matched, and the shapes and sizes of the second protrusion 31 and the first recess 22 are matched. For example, as Figure 1 As shown, the cross-sectional shapes of the first protrusion 21 and the first recessed portion 22 are both triangular, and the solder layer 20 is serrated as a whole, and the number of serrations may be 20-300. Figure 2 As shown, the cross-sectional shapes of the first protrusion 21 and the first recessed portion 22 are both rectangular. Figure 3 As shown, the cross-sectional shapes of the first protruding portion 21 and the first recessed portion 22 are both semicircular.

[0039] In some embodiments, the thickness d1 of the first protrusion 21 is 15 μm-40 μm, preferably 25 μm-30 μm. Figure 1 As shown, the thickness d1 of the first protrusion 21 is the distance between the highest protrusion of the first protrusion 21 and the outer surface of the substrate layer 10 .

[0040] In some embodiments, the thickness d2 of the first recessed portion 22 is 0-15 μm, preferably 3 μm-7 μm. Figure 1 As shown, the thickness d2 of the first recessed portion 22 is the distance between the lowest concave point of the first recessed portion 22 and the outer surface of the substrate layer 10. Figure 4 When the thickness d2 of the first recessed portion 22 is 0, the lowest point of the first recessed portion 22 abuts against the outer surface of the substrate layer 10 .

[0041] In some embodiments, the thickness d3 of the second protrusion 31 is 25 μm-40 μm, preferably 25 μm-30 μm. Figure 1 As shown, the thickness d3 of the second protrusion 31 is the distance between the highest protrusion of the second protrusion 31 and the inner surface of the black coating 30 .

[0042] In some embodiments, the thickness d4 of the second recessed portion 32 is 0-5 μm, preferably 3 μm-7 μm. Figure 1 As shown, the thickness d4 of the second recessed portion 32 is the distance between the lowest concave point of the second recessed portion 32 and the inner surface of the black coating 30. Figure 5 When the thickness d4 of the second recessed portion 32 is 0, the lowest concave point of the second recessed portion 32 abuts against the inner surface of the black coating 30 .

[0043] like Figure 6As shown, the thickness of the first recessed portion 22 and the second recessed portion 32 are both 0, that is, the lowest point of the first recessed portion 22 abuts against the outer surface of the substrate layer 10 , and the lowest point of the second recessed portion 32 abuts against the inner surface of the black coating 30 .

[0044] In some embodiments, the black coating 30 is a black metal oxide layer or a black metal alloy layer. Exemplarily, the black coating 30 is a black metal oxide layer, such as silver oxide, which has good corrosion resistance, aging resistance and electrical conductivity, can reduce the activity of the surface material of the soldering strip 100, improve the reliability of the component product, and greatly improve the stability of the soldering strip 100. It has a high adhesion with the solder layer 20, is not easy to fall off during use or production, and has better aesthetics after production.

[0045] In some embodiments, the substrate layer 10 may be a conductive metal material, such as copper, aluminum, etc.

[0046] In some embodiments, the solder layer 20 may be an alloy or metal with a relatively low melting point, such as a tin-lead alloy.

[0047] The melting point of the black coating 30 of this embodiment is higher than the melting point of the solder layer 20. Specifically, the melting point of the solder layer 20 can be 170°C-230°C, and the melting point of the black coating 30 can be 300°C-470°C. When the soldering strip 100 is welded, the welding temperature needs to be greater than the melting point of the solder layer 20 and less than the melting point of the black coating 30. When the soldering strip 100 enters the welding area, the solder layer 20 of the soldering strip 100 begins to melt in the high temperature environment. Because the melting point of the surface black coating 30 is higher than that of the solder layer 20, the black coating 30 will not fall off without external force. During welding, the soldering strip 100 is pressed down by the pressing needle of the string welding machine. The position where the soldering strip 100 contacts the battery grid line is subjected to the downward force of the pressing needle during welding, and the high temperature causes the solder layer 20 to melt and flow. The solder layer 20 adjacent to the battery grid line will break the outermost black coating 30 and contact the battery grid line to form a connection. In the embodiment of the utility model, since the thickness of the solder layer 20 is uneven, compared with the circular solder with uniform thickness in the related art, it is beneficial to the melting of the solder and the welding with the battery grid line during the welding process, and it can save the amount of solder, which is beneficial to the optimization of production costs.

[0048] The embodiment of the utility model also provides a photovoltaic module, including the above-mentioned welding strip 100 and a cell, wherein the welding strip 100 connects the cell. The photovoltaic module has a coordinated and beautiful appearance due to the use of the welding strip 100 with the black coating 30. At the same time, the black coating 30 has a high adhesion with the solder layer 20, and reduces the activity of the surface material of the welding strip 100, thereby improving the reliability of the module product.

[0049] Example 1

[0050] The diameter of the substrate layer is 0.26 mm, the thickness of the first recessed portion is 5 μm, the thickness of the first protruding portion is 30 μm, the thickness of the second protruding portion is 30 μm, and the thickness of the second recessed portion is 5 μm.

[0051] Example 2

[0052] The diameter of the substrate layer is 0.22 mm, the thickness of the first recessed portion is 3 μm, the thickness of the first protruding portion is 25 μm, the thickness of the second protruding portion is 25 μm, and the thickness of the second recessed portion is 3 μm.

[0053] Example 3

[0054] The diameter of the substrate layer is 0.30 mm, the thickness of the first recessed portion is 7 μm, the thickness of the first protruding portion is 30 μm, the thickness of the second protruding portion is 30 μm, and the thickness of the second recessed portion is 7 μm.

[0055] Comparative Example

[0056] Available silver round wire ribbon

[0057] The welding strips of Examples 1-3 and the comparative example were subjected to welding tensile force test, welding yield test and black coating preservation rate test after welding, respectively. The test results are shown in Table 1.

[0058] Welding tensile test: After welding the welding strips of Examples 1-3 and the comparative example to the battery cells respectively, the welding tensile test was performed using a welding tensile tester.

[0059] Welding yield test: Electroluminescence (EL) detection is performed on several welded products to identify cells without hidden cracks, cold solder joints, desoldering, black pieces and other defective cells as good products, and the yield rate is calculated, which is the welding yield rate.

[0060] Black coating preservation rate test after welding: Use a magnifying glass to observe the black coating of several products after welding, estimate the black coating drop area of ​​each product and calculate the black coating preservation rate after welding based on the drop area.

[0061] Table 1 shows the welding performance test results of the welding strips of Examples 1-3 and the comparative example.

[0062]

[0063] As can be seen from Table 1, the welding tensile test results of Examples 1-3 are all greater than the welding standard requirements, and the welding yield is not much different from the welding yield of the comparative example, indicating that the welding strips of the embodiments of the utility model can be applied to the existing welding process. Furthermore, the black coating preservation rate of the welding strips of Examples 1-3 after welding is not less than 98.0%, indicating that the black coating has strong adhesion and can still maintain a good appearance after welding.

[0064] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0065] The above embodiments only express the preferred implementation of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A welding strip, characterized in that: include: substrate layer; A solder layer, the solder layer is disposed on the outer side of the base material layer, the solder layer comprises a plurality of first protrusions and first recessed portions formed between adjacent first protrusions, the first protrusions are formed by protruding from the outer surface of the solder layer away from the base material layer; A black coating layer, the black coating layer is disposed around the outer side of the solder layer, the black coating layer comprises a plurality of second protrusions and second recessed portions formed between adjacent second protrusions, the second protrusions are formed by protruding from the inner surface of the black coating layer toward the base material layer; The first protrusion matches with the second recess, and the second protrusion matches with the first recess.

2. The welding strip according to claim 1, characterized in that: The substrate layer is in a strip-shaped structure and has a circular cross section. The diameter of the substrate layer is 0.18 mm-0.35 mm.

3. The welding strip according to claim 1, characterized in that: The cross-sectional shape of the first protrusion and / or the first recess is a triangle, a rectangle, a trapezoid or a semicircle.

4. The welding strip according to claim 1, characterized in that: The thickness of the first protrusion is 15 μm-40 μm, and the thickness of the first protrusion is the distance between the highest protrusion of the first protrusion and the outer surface of the substrate layer.

5. The welding strip according to claim 4, characterized in that: The thickness of the first depressed portion is 0-15 μm, and the thickness of the first depressed portion is the distance between the lowest concave point of the first depressed portion and the outer surface of the substrate layer.

6. The welding strip according to claim 5, characterized in that: The thickness of the second protrusion is 25 μm-40 μm, and the thickness of the second protrusion is the distance between the highest protrusion point of the second protrusion and the inner surface of the black coating.

7. The welding strip according to claim 6, characterized in that: The thickness of the second depressed portion is 0-5 μm, and the thickness of the second depressed portion is the distance between the lowest concave point of the second depressed portion and the inner surface of the black coating.

8. The welding strip according to claim 1, characterized in that: The number of the first protrusions is 20-300.

9. The welding strip according to claim 1, characterized in that: The black coating is a black metal oxide layer or a black metal alloy layer, and the melting point of the black coating is higher than the melting point of the solder layer.

10. A photovoltaic module, characterized in that: include: The soldering ribbon and the battery cell according to any one of claims 1 to 9, wherein the soldering ribbon is connected to the battery cell.

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