US-12628438-B2 - Welding ribbon component and preparation method therefor, and photovoltaic module

US12628438B2US 12628438 B2US12628438 B2US 12628438B2US-12628438-B2

Abstract

The present application provides a welding ribbon component and a preparation method therefor, and a photovoltaic module. The welding ribbon component includes: a first welding ribbon segment, a second welding ribbon segment, and a connecting segment, and the connecting segment is located between the first welding ribbon segment and the second welding ribbon segment. The first welding ribbon segment includes a first welding ribbon body, a surface of the first welding ribbon body being provided with a depression; and a first welding coating located at least on a surface of an inner wall of the depression. The welding ribbon component of the present application can increase the thickness of the welding coating to improve the welding tension, and can reasonably control the thickness to prevent cracking, while also achieving high-density packaging.

Inventors

Qi Guo
Ruizhi Luo
Daoren GONG

Assignees

Anhui Huasun Energy Co., Ltd.

Dates

Publication Date: 20260512
Application Date: 20230329
Priority Date: 20221027

Claims (10)

1 . A welding ribbon component, comprising a first welding ribbon segment, a second welding ribbon segment and a connecting segment, wherein the connecting segment is located between the first welding ribbon segment and the second welding ribbon segment; and the first welding ribbon segment comprises a first welding ribbon body, a surface of the first welding ribbon body being provided with a depression; and a first welding coating located at least on a surface of an inner wall of the depression; wherein the second welding ribbon segment comprises: a second welding ribbon body; a welding surface of the second welding ribbon body at least being a plane, the welding surface and the depression being located on upper and lower side surfaces of the welding ribbon component in a height direction respectively; and a second welding coating at least located on the welding surface of the second welding ribbon body; wherein one end of the connecting segment is connected with one end of the first welding ribbon segment, and the other end of the connecting segment is connected with one end of the second welding ribbon segment; wherein a thickness of the connecting segment gradually decreases in a direction from the first welding ribbon segment to the second welding ribbon segment; and wherein the first welding ribbon body is welded to one side of a light receiving surface of a first battery piece through a first welding coating and the second welding ribbon body is welded to one side of a backlight surface of a second battery piece through the second welding coating.
2 . The welding ribbon component of claim 1 , wherein the first welding ribbon body has a first cross section perpendicular to the length direction of the first welding ribbon body, an outer edge line of the first cross section comprises a first line region and a second line region connected with the first line region, the first line region is located on the surface of the inner wall of the depression, and the second line region is located on an outer surface of the first welding ribbon body at two ends of the depression; wherein-a shape of the first line region comprises a circular arc, a “V”-shape or a trapezoid; and wherein a shape of the second line region comprises a circular arc, a triangle, a trapezoid or a rectangle.
3 . The welding ribbon component of claim 1 , wherein a shape of a cross section of the second welding ribbon body perpendicular to the length direction of the second welding ribbon body comprises a rectangular or trapezoidal shape or a partially arced surface.
4 . The welding ribbon component of claim 1 , wherein one side of the connecting segment facing away from the depression is an inclined plane.
5 . The welding ribbon component of claim 1 , wherein a melting point of the first welding coating is smaller than a melting point of the first welding ribbon body, the melting point of the second welding coating is smaller than the melting point of the second welding ribbon body.
6 . The welding ribbon component of claim 1 , wherein the first welding coating has a thickness ranging from 20 μm to 30 μm, and the second welding coating has a thickness ranging from 15 μm to 22 μm.
7 . The welding ribbon component of claim 2 , wherein a depth of the depression is smaller than or equal to a half of a maximum distance between any two points in the second line region; a maximum distance between any two points in the second line region is in a range from 250 μm to 350 μm.
8 . The welding ribbon component of claim 1 , wherein the size of the second welding ribbon body in the height direction is smaller than the maximum size of the first welding ribbon body in a height direction.
9 . The welding ribbon component of claim 1 , wherein the size of the second welding ribbon body in the height direction is in a range from 130 μm to 200 μm.
10 . The welding ribbon component of claim 1 , wherein the first welding coating comprises a first tin-bismuth-lead welding coating or a first tin-bismuth-silver welding coating; the second welding coating comprises a second tin-bismuth-lead welding coating or a second tin-bismuth-silver welding coating.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application claims priority to Chinese Patent Application No. 202211339959.9, entitled “WELDING RIBBON COMPONENT AND PREPARATION METHOD THEREFOR, AND PHOTOVOLTAIC MODULE”, filed to the China Patent Office on Oct. 27, 2022, the entire content of which is incorporated herein by reference. TECHNICAL FIELD The present application relates to the field of solar cells, to a welding ribbon component and a preparation method therefor, and a photovoltaic module. BACKGROUND Solar cells are apparatuses that directly or indirectly convert solar radiation energy into electrical energy through photoelectric or photochemical effects by absorbing sunlight. After the preparation of solar battery pieces, it is necessary to use welding ribbon components to weld the solar battery pieces together to form a cell string, and then form the cell string into a solar cell assembly. Heterojunction cells, as an efficient technical route that has attracted high attention in the industry in recent years, have become a recognized ultimate solution for future cell technology in the industry due to their high photoelectric conversion efficiency, excellent performance, and large cost reduction space, and they are also referred to as the leading technology for the next generation of commercial photovoltaic production in the industry. However, the heterojunction cells are limited by special properties of transparent conducting oxide (TCO) and other conductive layers, such as indium tin oxide (ITO), which is sensitive to high-temperature and requires a low-temperature welding process, and the production cost is high, which restricts the rapid development of the heterojunction cells. Due to the limitations of the low temperature in the production process of the heterojunction cells, only low-temperature tin-lead-bismuth component welding ribbons with higher prices can be adopted. At the same time, to reduce costs, enterprises are increasingly paying attention to a path of achieving “high-density packaging”, that is, more battery pieces are added within a limited size range to improve power generation efficiency, hoping to share the constantly rising single watt cost with higher power generation efficiency. A conventional welding ribbon component is a whole round wire since the contact area between the round-wire-shaped welding ribbon component and the battery pieces is too small, the conductivity is restricted, the welding tension is insufficient, and after welding, it is prone to occurring phenomena of false welding and desoldering, and the one-time forming rate of a photovoltaic module is reduced. In addition, after a welding coating on the welding ribbon component is melted, it will gather at positions of silver paste points on the battery pieces to form molten aggregates. When there are gaps between the welding ribbon component and the battery pieces, these molten aggregates will condense and form irregular foreign matter points. When the battery pieces which are connected by the welding ribbon component in series are covered by upper glass and subjected to lamination processing by using a lamination machine, such foreign matter points will greatly increase the probability of single-point stress on the battery pieces, causing hidden cracks. Therefore, a method for increasing the thickness of the welding coating is adopted currently and commonly to ensure a sufficient contact area. However, a thickness of a tin-lead-bismuth coating of the low-temperature welding ribbon is more than 5 μm higher than that of a welding ribbon coating for a conventional passivated emitter and rear cell (PERC), the increase of the thickness of the welding coating will lead to an increase in the volume of the foreign matter points, and the problem of cracking of the battery piece is exacerbated. Therefore, it is necessary to seek a welding technical solution that can increase the thickness of the welding coating to improve the welding tension and can reasonably control the thickness to prevent cracking, while also achieving high-density packaging. SUMMARY OF THE INVENTION Therefore, the technical problem to be solved in the present application is to overcome the problems that the welding tension of a welding ribbon component on battery pieces is insufficient and cracking of the battery pieces is prone to in the prior art, and achieve a high-density packaging technology, to provide a welding ribbon component and a preparation method therefor, and a photovoltaic module. The first aspect of the present application provides a welding ribbon component, including a first welding ribbon segment, a second welding ribbon segment, and a connecting segment, and the connecting segment is located between the first welding segment and the second welding ribbon segment; and the first welding ribbon segment includes: a first welding ribbon body, a surface of the first welding ribbon body being provided with a depression; and a firs