CN108987517A - The trapezoidal copper-based structure of optically focused painting tin copper strips - Google Patents

Abstract

The invention relates to a trapezoidal copper-based structure of a light-concentrating tin-coated copper strip. The cross-sectional profile of the copper-based structure is trapezoidal, and there are two surfaces of the first surface and the second surface along the length direction. The angle is 46°～90°. Surface 1 and surface 2 are respectively equipped with a reflective surface structure composed of triangular peaks and inverted trapezoidal grooves. The distance between two adjacent triangular peaks or the distance between two inverted trapezoidal grooves is 0.1mm ~0.4mm, the height of the triangular peak or the depth of the inverted trapezoidal groove is 0.025mm~0.12mm. The trapezoidal slopes on both sides of the trapezoidal copper-based structure form an included angle with surface 2 to maximize the utilization of light incident on the photovoltaic module cells; surface 1 and surface 2 are equipped with reflective surface structures, which is conducive to the dual-wave modules to increase the power To a higher level, the concentrating tin-coated copper strip product prepared by the copper-based structure is connected to the battery after high-temperature series welding, and the internal stress of the material increases due to thermal expansion to release the stress.

Description

Trapezoidal copper-based structure of light-spotting tin-coated copper strips

technical field

The invention relates to a trapezoidal copper-based structure of a light-condensing tin-coated copper strip.

Background technique

At present, the tin-coated copper strip used in the solar photovoltaic industry for series welding of cells is based on a flat copper-based strip with uniform width and thickness, and its surface is coated with 15-30 microns by electroplating or hot-dip plating. Tin-based solder to achieve the purpose of welding with the grid wire of the cell. Since the tin-coated copper strips are welded in series on the surface of the battery sheet, a part of the light-receiving area of the battery is blocked, thereby reducing the light utilization rate. Therefore, it is necessary to set up a structure with reflective conditions on the light-receiving surface of the tin-coated copper strip, which is conducive to the light passing through the tempered glass of the component and irradiating the reflective structure surface on the surface of the strip, and then reflecting back to the glass again, and being reflected by the glass again through the principle of optical total diffuse reflection Back to the surface of the battery to achieve the purpose of secondary use of light.

The existing tin-coated copper strip with reflective structure on the surface, due to the uneven coating (thicker or thinner) on the welding surface, will cause the problem of virtual welding and over-soldering in the process of stringing the cells, especially the backside. Welding is particularly serious. Since the reflective structure on the surface of the tin-coated copper strip is set on one side of the surface of the tin-coated copper strip, the internal stress increases after being stretched and welded by the serial welding equipment, especially after lamination. There is no gap between the cells to release the residual stress, which will easily lead to the risks of cracks and fragments in the laminated photovoltaic module cells. Moreover, the current heterogeneous tin-coated copper strips in the industry are only suitable for ordinary photovoltaics and cannot be used in On the components of double glass technology. Therefore, there is a need for a high-efficiency concentrating tin-coated copper strip product that satisfies the need for a reflective structure on the surface, reduces the risk of debris after lamination, and is suitable for the manufacture of conventional or double-glass components. The key to preparing this product lies in the preparation of high The copper base material and its surface structure design used in high-efficiency concentrating tin-coated copper strips.

Publication No. CN204243063U discloses reflective ribbons and photovoltaic modules with the reflective ribbons. Reflective strips are attached to the flat front of flat conventional ribbons. Unevenness, when the reflective strip is attached, it will cause problems such as unreliable attachment, edge curling and curling, and the cumbersome process in the mass production process of this product will cause higher cost and unstable quality.

Publication No. CN204441304U discloses a hot-dip reflective soldering ribbon. Only one side of the soldering ribbon is provided with an indentation surface (reflective surface), which cannot maximize the utilization rate of light absorbed by the battery. After stretching, the stress becomes larger and cannot be released, leading to the risk of cell fragments and cracks after lamination (especially after the reliability mechanical load loading test of photovoltaic modules).

Publication No. CN105374885B discloses a heterogeneous high-efficiency photovoltaic ribbon. Publication No. CN205016540U discloses a high-utilization ribbon, which is designed for reflective surface twill and reflective surface with a coupling platform structure. The immersion tin plating process will cause tin alloy solder to fill the grooves or coupling platforms set on the reflective surface, which will eventually lead to a large reduction in the area of the reflective surface that reflects light and cannot achieve ideal optical gain. Preparation, there is a lot of water pollution and consumption, and it also poses a greater threat to human health, so it is not suitable for the promotion of mass production. Secondly, due to the particularity of the electroplating process, the production cost is relatively higher than that of the hot-dip plating process.

Publication No. CN106024959A discloses a structured high-gain reflective solder ribbon for solar cells. Its reflective structure cannot maximize the light utilization of component cells, and the solder coatings on its reflective surface and soldering surface are two solders with different melting points. This technical route is too idealistic, and the current technology is difficult to solve the problem of coating two or more tin alloys on the surface of the same material, or the cost is too high to achieve batch preparation.

The common feature of the above technologies is that the shape of the product configuration is rectangular, which cannot effectively maximize the utilization rate of the light entering the battery, and the welding surface is smooth due to the surface of the copper base strip, and the hot-dip plating process After tinning, the surface is actually a circular arc surface, and uneven coating can easily lead to false welding, especially after lamination, there is no gap between the tin-coated copper strip and the cell to release residual stress, resulting in an increase in fragmentation rate.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide a trapezoidal copper-based structure of a light-condensing tin-coated copper strip.

The purpose of the present invention is achieved through the following technical solutions:

The trapezoidal copper-based structure of the light-spotting tin-coated copper strip is characterized by: the cross-sectional profile of the copper-based structure is trapezoidal, and there are two surfaces of surface 1 and surface 2 along the length direction. Surface 1 and surface 2 are respectively provided with triangular The reflective surface structure is composed of peaks and inverted trapezoidal grooves, the distance between two adjacent triangular peaks or the distance between two inverted trapezoidal grooves is 0.1mm~0.4mm, the height of the triangular peaks or the depth of the inverted trapezoidal grooves is 0.025mm~ 0.12mm.

Furthermore, in the above-mentioned trapezoidal copper-based structure of the light-concentrating tin-coated copper strip, the included angle between the trapezoidal slope and the second surface of the copper-based structure is 46°-90°.

Furthermore, in the above-mentioned trapezoidal copper-based structure of the light-concentrating tin-coated copper strip, the angle between the two waist surfaces of the inverted trapezoidal groove is 90°-138°.

Furthermore, in the above-mentioned trapezoidal copper-based structure of the light-concentrating tin-coated copper strip, the length of the bottom surface of the inverted trapezoidal groove is 0.01mm-0.03mm.

Compared with the prior art, the present invention has significant advantages and beneficial effects, which are embodied in the following aspects:

① The invention has a unique design and a novel structure. The trapezoidal copper-based structure forms a trapezoidal concentrating tin-coated copper strip or reflective soldering strip with a reflective effect. The angle between the trapezoidal slope and the second surface set on both sides of the trapezoidal copper-based structure is 46°-90° , which can maximize the absorption of the light utilization rate incident on the photovoltaic module cells;

②The surface 1 and surface 2 of the copper-based structure are provided with a reflective surface structure composed of triangular peaks and inverted trapezoidal grooves. This structure on the surface is reflected to the surface of the cell for a second time, so that the power of the photovoltaic module can obtain a large photoelectric gain, which is beneficial to the dual-wave module to increase the power to a higher level;

③The concentrating tin-coated copper strip product prepared by the copper-based structure and the battery after high-temperature series welding can release the stress due to the increase of the internal stress due to thermal expansion, and greatly reduce the fragmentation rate of the component after layout, lamination, and lamination. risk, significantly reducing the production cost of photovoltaic modules.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and thus It should be regarded as a limitation on the scope, and those skilled in the art can also obtain other related drawings based on these drawings without creative work.

Fig. 1: structural representation of the present invention;

Figure 2: A partially enlarged schematic diagram of the triangular peak and the inverted trapezoidal groove;

Figure 3: Schematic diagram of the angle between the trapezoidal slope and the second surface;

Figure 4: Schematic diagram of the connection structure between the concentrating tin-coated copper strip and the first cell;

Figure 5: Schematic diagram of the connection structure between the concentrating tin-coated copper strip and the second cell;

Figure 6: Schematic diagram of the light gain of the concentrating tin-coated copper strip.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Accordingly, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts belong to the protection scope of the present invention.

It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures. Meanwhile, in the description of the present invention, orientation terms, order terms, etc. are only used to distinguish descriptions, and cannot be understood as indicating or implying relative importance.

As shown in Figure 1, the trapezoidal copper-based structure of the light-concentrating tin-coated copper strip, the cross-sectional profile of the copper-based structure is trapezoidal, and there are two surfaces of surface 101 and surface 2 102 along the length direction, surface 101 and surface 2 102 is provided with a reflective surface structure composed of triangular peaks and inverted trapezoidal grooves. The height of the peak or the groove depth D of the inverted trapezoidal groove is 0.025mm~0.12mm, the angle B between the two waists of the inverted trapezoidal groove is 90°~138°, and the length C of the bottom surface of the inverted trapezoidal groove is 0.01mm~0.03mm . As shown in FIG. 3 , the included angle E between the trapezoidal inclined surface 103 and the second surface 102 of the copper-based structure is 46°-90°.

The above-mentioned trapezoidal copper base with two-sided reflective surface structure, after the tin plating process, prepares the light-concentrating tin-coated copper strip (coating tin solder on the surface of the copper base) with the structure shown in Figure 4 and Figure 5, the structure of Figure 4 and Figure 5 Any side of the light-spotting tin-coated copper strip is arranged alternately and cyclically according to the customer’s size in the length direction, and the surface 2 102 of the light-spotting tin-coated copper strip is welded to the front grid line of the first cell 103 in a cycle section, as shown in the figure As shown in FIG. 4 , the first surface 101 of the light-concentrating tin-coated copper strip is welded to the back grid of the second battery sheet 104 , as shown in FIG. 5 .

The above-mentioned light-concentrating tin-coated copper strip is applied to a photovoltaic module. As shown in FIG. The reflected light N is reflected towards the glass 105, and secondly reflected to the surface of the first battery sheet 103 by the glass medium and then used by the battery. Therefore, the structural design of the present invention is conducive to maximizing the secondary utilization rate of the light of the photovoltaic module, and compensates for the tin-coated copper strip. Shade and reduce the power loss caused by the light-receiving area of the battery. Concentrating tin-coated copper strips are used in dual-wave modules, because the front and back sides of the module receive light, which will further increase the power gain of the module.

In summary, the present invention has a unique design and a novel structure. The trapezoidal copper-based structure forms a trapezoidal concentrating tin-coated copper strip or reflective soldering strip with a reflective effect. °～90°, it can maximize the absorption of light incident on the cells of photovoltaic modules.

The surface 1 and surface 2 of the copper-based structure are provided with a reflective surface structure composed of triangular peaks and inverted trapezoidal grooves. This structure on the surface is reflected to the surface of the battery sheet again, so that the power of the photovoltaic module can obtain a large photoelectric gain, which is beneficial to the dual-wave module to increase the power to a higher level.

At the same time, the concentrating tin-coated copper strip product prepared by the copper-based structure and the battery after high-temperature series welding can release the stress after the internal stress of the thermal expansion increases, which greatly reduces the fragmentation rate of the component after layout, lamination, and lamination. risk, significantly reducing the production cost of photovoltaic modules.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention. It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present invention, which should be included in the scope of the present invention. within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope described in the claims.

It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is a relationship between these entities or operations. any such actual relationship or order exists between them. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

Claims (4)

1. the trapezoidal copper-based structure of optically focused painting tin copper strips, it is characterised in that: the cross-sectional profiles of copper-based structure are trapezoidal, along length Direction has two faces in face one (101) and face two (102), is respectively arranged on face one (101) and face two (102) with triangle The reflective surface structure that peak and upside-down trapezoid slot staggered cycles are constituted, the spacing at adjacent two triangle peak or two upside-down trapezoid slots Spacing (A) is 0.1mm~0.4mm, and the height of triangle peaks or the groove depth (D) of upside-down trapezoid slot are 0.025mm~0.12mm.

2. the trapezoidal copper-based structure that optically focused according to claim 1 applies tin copper strips, it is characterised in that: copper-based structure it is trapezoidal The angle (E) in inclined-plane (103) and face two (102) is 46 °~90 °.

3. the trapezoidal copper-based structure that optically focused according to claim 1 applies tin copper strips, it is characterised in that: the two of upside-down trapezoid slot Angle (B) is 90 °~138 ° between central plane.

4. the trapezoidal copper-based structure that optically focused according to claim 1 applies tin copper strips, it is characterised in that: the bottom of upside-down trapezoid slot Face length (C) is 0.01mm~0.03mm.