US-20260129979-A1 - PHOTOVOLTAIC MODULE

US20260129979A1US 20260129979 A1US20260129979 A1US 20260129979A1US-20260129979-A1

Abstract

The present disclosure relates to the field of photovoltaics and provides a photovoltaic module. The photovoltaic module includes: cells, which includes welding regions and collection regions arranged along a first direction; a surface of the cells has a plurality of fingers arranged along a second direction, each finger includes at least two welding fingers located in the welding region and collection fingers located in the collection region, where the welding fingers are arranged along the second direction, and each of the at least two welding fingers is electrically connected to the same collection finger; a connecting member, located on the cells, the connecting member is electrically connected to the plurality of fingers arranged along the second direction, and the connecting member is welded to each welding finger. The photovoltaic module provided by the embodiments of the present disclosure can at least reduce power generation loss.

Inventors

Peiting ZHENG
Huimin Li
Menglei Xu
Jie Yang
Xinyu Zhang

Assignees

Jinko Solar Co., Ltd.
ZHEJIANG JINKO SOLAR CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20251111
Priority Date: 20241107

Claims (20)

1 . A photovoltaic module, comprising: solar cells, a respective cell of the solar cells including welding regions and collection regions alternately arranged along a first direction, the welding regions including a first welding region, and the collection regions including a first collection region adjacent to the first welding region; a plurality of rows of fingers, arranged at intervals along a second direction, a respective row of fingers including at least two welding fingers located in the first welding region and a collection finger located in the first collection region, wherein the at least two welding fingers are arranged along the second direction, and the at least two welding fingers are electrically connected to the collection finger; a connecting member, electrically connected to at least some fingers in the plurality of rows of fingers, and welded to the at least two welding fingers.
2 . The photovoltaic module according to claim 1 , wherein a welding finger of the at least two welding fingers has a width in the second direction that is greater than or equal to a width of the collection finger in the second direction.
3 . The photovoltaic module according to claim 1 , wherein the at least two welding finger includes a first type of fingers and a second type of fingers, where the first type of fingers and the collection finger are made of a burn-through paste, and the second type of fingers are made of a non-burn-through paste.
4 . The photovoltaic module according to claim 3 , wherein a welding finger of the at least two welding fingers include: a first sub-finger and a second sub-finger which are stacked, the second sub-finger is located between the connecting member and the first sub-finger, and materials of the first sub-finger and the second sub-finger are different.
5 . The photovoltaic module according to claim 1 , wherein the cells are back-contact cells, the plurality of rows of fingers include first fingers of a first conductivity type and second fingers of a second conductivity type, the first fingers include first welding fingers corresponding to the first welding region and first collection fingers corresponding to the first collection region, the second fingers include second welding fingers corresponding to a second welding region and second collection fingers corresponding to a second collection region, the first welding region and the second collection region are directly opposite to each other along the second direction, and the second welding region and the first collection region are directly opposite to each other along the second direction; the photovoltaic module further includes: an insulating layer, the insulating layer being located between the connecting member and the second collection fingers.
6 . The photovoltaic module according to claim 5 , wherein the insulating layer is located on the first fingers and the second fingers, extends in the second direction, and is provided with hollowed-out regions configured to expose the first welding fingers.
7 . The photovoltaic module according to claim 6 , wherein at least two of the first welding fingers of the same first fingers contact each other to form a welding pad, and a width of the welding pad along the second direction is greater than a width of the first collection finger along the second direction.
8 . The photovoltaic module according to claim 5 , wherein, in a region corresponding to each of the connecting member, a top surface of a respective welding finger of the first welding fingers close to the insulating layer is higher than a top surface of a respective welding finger of the first welding fingers far from the insulating layer.
9 . The photovoltaic module according to claim 6 , wherein a distance between the insulating layer and the first welding fingers is proportional to a thickness of the insulating layer.
10 . The photovoltaic module according to claim 6 , wherein, along the second direction and toward the first welding fingers, a thickness of the insulating layer decreases.
11 . The photovoltaic module according to claim 6 , wherein each of the second collection fingers comprise two broken fingers and a break located between the two broken fingers, the break corresponds to the first welding region, the broken fingers are located on both sides of a respective connecting member and are insulated from the respective connecting member.
12 . The photovoltaic module according to claim 5 , wherein the insulating layer not only covers the first welding region but also extends into a partial width of the first collection region, and a width of the insulating layer extending into the first collection region is in a range of 0.5 mm to 2.5 mm.
13 . The photovoltaic module according to claim 1 , wherein the connecting member has a core-shell structure including a conductive layer and a solder layer covering the conductive layer, and the solder layer is made of at least one of a tin-zinc alloy, a tin-bismuth alloy, or a tin-indium alloy.
14 . The photovoltaic module according to claim 13 , wherein a cross-sectional shape of the connecting member, perpendicular to the first direction, is one of a circle, a triangle, or an irregular shape.
15 . The photovoltaic module according to claim 1 , further comprising an adhesive film covering a surface of a cell string formed by the cells, wherein a material of the adhesive film is at least one of ethylene-vinyl acetate (EVA), polyolefin elastomer (POE), or polyvinyl butyral (PVB).
16 . The photovoltaic module according to claim 15 , further comprising a cover plate covering a side of the adhesive film away from the cell string, wherein the cover plate is made of glass or plastic, and a surface of the cover plate facing the adhesive film is an uneven surface.
17 . The photovoltaic module according to claim 1 , wherein the number of the at least two welding fingers in each row of fingers is in a range of 2 to 5.
18 . The photovoltaic module according to claim 2 , wherein a difference between the width of a welding finger of the at least two welding fingers in the second direction and the width of the collection finger in the second direction is in a range of 0.5 μm to 10 μm.
19 . The photovoltaic module according to claim 13 , wherein when the solder layer is a tin-bismuth alloy, a melting point of the tin-bismuth alloy is less than or equal to 129° C.
20 . The photovoltaic module according to claim 12 , wherein the width of the insulating layer extending into the first collection region is in a range of 1.0 mm to 2.0 mm.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of PCT Patent Application No. PCT/CN2025/128105, filed on Oct. 16, 2025, which claims priority to Chinese Patent Application No. 202411586844.9, titled “PHOTOVOLTAIC MODULE,” filed on Nov. 7, 2024, each of which are incorporated herein by reference in its entirety. TECHNICAL FIELD Embodiments of the present application relate to the field of photovoltaics, and in particular, to a photovoltaic module. BACKGROUND Solar cells are devices that directly convert light energy into electrical energy through the photovoltaic effect or photochemical effect. A single solar cell cannot generate electricity for direct use. It must be connected in series and parallel via ribbons with several other single cells and strictly encapsulated into a module before use. The solar cell module (also called a solar cell panel) is the core part of a solar power generation system, and also the most important part of the solar power generation system. The function of a solar cell module is to convert solar energy into electricity, which is then either sent to a battery for storage or used to drive a load. The busbars and fingers on the solar cell are key components that ensure solar conversion efficiency. The busbars are responsible for collecting solar energy, while the fingers increase light absorption and current transmission efficiency. The busbars and fingers work together to ensure maximum absorption and conversion efficiency of solar energy. The busbars are directly connected to the external leads of the cell (i.e., the connecting members) and are the relatively thick parts. The fingers serve to collect current and transmit the current to the busbars, are the relatively thin parts, and are made into narrow, fine fingers to overcome the resistance of the diffusion layer. However, the front-side fingers (busbars and fingers) block a portion of the silicon wafer. The light energy falling on these fingers cannot be converted into electricity, resulting in waste. Furthermore, the primary component of the paste used to make these fingers is silver, a relatively expensive precious metal, thus also involving cost issues. Based on this, technicians have enabled more and finer connecting members to directly connect to the cell fingers, collecting current while achieving cell interconnection, and eliminating traditional busbars at the cell level, known as “busbar-free” technology. However, there are still many factors affecting the yield and the power generation loss of photovoltaic modules, such as the welding effect and the welding yield between the connecting members and the fingers. SUMMARY The embodiments of the present application provide a photovoltaic module, which is at least beneficial for reducing power generation loss. According to some embodiments of the present application, an embodiment of the present application provides a photovoltaic module, including: cells, a respective cell of the cells including welding regions and collection regions alternately arranged along a first direction; a surface of the cells having a plurality of fingers arranged along a second direction, a respective row of fingers including at least two welding fingers located in the welding region and collection fingers located in the collection region, where the welding fingers are arranged along the second direction, and the at least two welding fingers are electrically connected to the same collection finger; a connecting member, the connecting member being located on the cells, the connecting member being electrically connected to the plurality of fingers arranged along the second direction, and the connecting member being welded to each of the welding fingers. In some embodiments, a width of a welding finger of the at least two welding fingers in the second direction is greater than or equal to a width of the collection finger in the second direction. In some embodiments, the at least two welding fingers include a first type of fingers and a second type of fingers, the first type of fingers and the collection fingers are made of a burn-through paste, and the second type of fingers are made of a non-burn-through paste. In some embodiments, the at least two welding fingers include: a first sub-finger and a second sub-finger which are stacked, the second sub-finger is located between the connecting member and the first sub-finger, and materials of the first sub-finger and the second sub-finger are different. In some embodiments, the cells are back-contact cells, the fingers include first fingers of a first conductivity type and second fingers of a second conductivity type, the first fingers include first welding fingers corresponding to a first welding region and first collection fingers corresponding to a first collection region, the second fingers include second welding fingers corresponding to a second welding region and second collection fingers corresponding to a second coll