Solar photovoltaic cell
By replacing silver grid lines with metal wire layers and double-layer seed layer grid lines, the problems of high silver consumption, large shading area, and high resistance loss are solved, thereby improving the output power and photoelectric conversion efficiency of solar photovoltaic cells.
Patent Information
- Application Number
- CN202520029908.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-06
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2035-01-06
AI Technical Summary
Existing solar photovoltaic cells suffer from problems such as high silver consumption, large shading area, complex current transmission path, high resistance loss, and low output power.
A metal wire layer is used to replace the silver gate line. The seed layer gate line structure is a double-layer structure, including a first gate line layer and a second gate line layer, and a metal wire layer is covered on top of it. The metal wire layer and the seed layer gate line structure are fixed by welding or conductive adhesive material. Current is conducted vertically to reduce resistance loss.
It reduces material costs, lowers the shading area, increases the output power and photoelectric conversion efficiency of photovoltaic modules, simplifies the current transmission path, and reduces resistance loss.
Smart Images
Figure CN223943105U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of solar cell technology, and in particular to a solar photovoltaic cell. Background Technology
[0002] In the existing crystalline silicon photovoltaic industry chain, silicon substrates are used to manufacture solar cells, and the surface electrodes of the solar cells are silver grid lines formed by printing silver paste. The silver grid lines are generally divided into mutually perpendicular main grids and fine grids. Among them, the fine grids are uniformly and densely arranged in parallel on the surface of the solar cell to collect local currents on the surface of the solar cell; the main grids are uniformly arranged with a larger spacing to collect the currents of the fine grids on both sides.
[0003] This type of solar cell, made with silver paste, consumes a large amount of silver and has a large light-shielding area, leading to reduced efficiency. Furthermore, the electrode structure using a silver main grid and silver fine grid requires conductive solder strips to be covered on the main grid during module fabrication. The current transmission path is complex: current is collected through the fine grid, then laterally transmitted through the fine grid to the main grid, then from the main grid to the conductive solder strip, and finally out of the solar cell. This complex current transmission path results in significant resistance loss, reducing the output power of both the cell and the module. Utility Model Content
[0004] The purpose of this invention is to provide a solar photovoltaic cell to solve the technical problems of existing solar photovoltaic cells, such as high silver consumption, large shading area, complex current transmission path, high resistance loss, and low output power.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A solar photovoltaic cell includes a cell substrate, a seed layer grid structure, and a metal wire layer, wherein:
[0007] The front and back sides of the battery cell substrate are respectively covered with a seed layer grid line structure, and the seed layer grid line structure includes a first grid line layer and a second grid line layer stacked sequentially in a direction away from the battery cell substrate.
[0008] The metal wire layer covers the seed layer grid structure.
[0009] As an optional embodiment, the wire layer includes wires arranged in parallel and / or vertically.
[0010] As an optional embodiment, the equivalent diameter of the metal wires in the metal wire layer is 5-70 μm.
[0011] As an optional embodiment, the cross-section of the metal wires in the metal wire layer includes one or more of the following: triangle, circle, and rectangle.
[0012] As an optional embodiment, the main material of the metal wires in the metal wire layer includes one or more of oxygen-free copper and pure copper.
[0013] As an optional embodiment, the surface of the metal wires in the metal wire layer is provided with a tin-based alloy coating.
[0014] As an optional embodiment, the surface of the metal wires in the metal wire layer has high reflectivity.
[0015] As an optional embodiment, the main material of the first gate layer includes one or more of nickel, titanium, tungsten, cobalt, tantalum, nickel-tungsten alloy, nickel-cobalt alloy, titanium-tungsten alloy, and nickel-titanium alloy.
[0016] As an optional embodiment, the main material of the second gate layer includes one or more of tin and tin-bismuth alloy.
[0017] As an optional embodiment, the seed layer grid structure is connected and fixed to the metal wire layer by welding or conductive adhesive material.
[0018] The beneficial effects of this utility model are:
[0019] The solar photovoltaic cell provided by this utility model includes a cell substrate, a seed layer grid structure, and a metal wire layer, wherein: the front and back sides of the cell substrate are respectively covered with the seed layer grid structure, and the seed layer grid structure includes a first grid layer and a second grid layer stacked sequentially along the direction away from the cell substrate; the metal wire layer covers the seed layer grid structure.
[0020] The solar photovoltaic cell provided by this invention abandons the grid lines made of silver paste, and instead uses metal wires to collect and transmit local currents on the cell surface. Using extremely fine metal wires instead of expensive silver grid lines not only reduces material costs but also reduces the shading area of the photovoltaic module, thus improving the output power of the photovoltaic module. Furthermore, the seed layer grid line structure is a double-layer grid line structure, including a first grid line layer and a second grid line layer. The first grid line layer mainly serves to conduct current, while the second grid line layer mainly serves to protect the first grid line layer and connect the first grid line layer and the metal wire layer. This double-layer grid line structure is more conducive to current conduction. In addition, the seed layer grid line structure is covered with a metal wire layer. This structure avoids current conduction parallel to the cell surface in the grid lines, and only allows current conduction perpendicular to the cell surface from the seed layer grid line structure to the metal wire layer. This reduces resistance loss and further improves the photoelectric conversion efficiency of the cell. Attached Figure Description
[0021] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of the structure of a solar photovoltaic cell provided in an embodiment of the present invention.
[0023] icon:
[0024] 1-Battery cell substrate; 2-Seed layer grid structure; 21-First grid layer; 22-Second grid layer; 3-Metal wire layer. Detailed Implementation
[0025] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0026] It should be noted that in the description of this utility model, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0027] It should be noted that in the description of this utility model, the terms "connection" and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or a connection through an intermediate medium; they can refer to a mechanical connection or an electrical connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0028] This utility model embodiment provides a solar photovoltaic cell, referencing... Figure 1 The solar photovoltaic cell includes a cell substrate 1, a seed layer grid structure 2, and a metal wire layer 3, wherein:
[0029] The front and back sides of the battery cell substrate 1 are respectively covered with a seed layer grid structure 2. The seed layer grid structure 2 includes a first grid layer 21 and a second grid layer 22 stacked sequentially along the direction away from the battery cell substrate 1.
[0030] The metal wire layer 3 covers the seed layer gate structure 2.
[0031] The solar photovoltaic cell provided by this invention abandons the grid lines made of silver paste, and instead uses metal wires to collect and transmit local currents on the cell surface. Using extremely fine metal wires instead of expensive silver grid lines not only reduces material costs but also reduces the shading area of the photovoltaic module, which is beneficial for improving the output power of the photovoltaic module. Furthermore, the seed layer grid structure 2 is a double-layer grid structure, including a first grid layer 21 and a second grid layer 22. The first grid layer 21 mainly conducts current, while the second grid layer 22 mainly protects the first grid layer 21 and connects the first grid layer 21 and the metal wire layer 3. This double-layer grid structure is more conducive to current conduction. In addition, the seed layer grid structure 2 is covered with a metal wire layer 3. This structure avoids current conduction parallel to the cell surface in the grid lines, and only allows current conduction perpendicular to the cell surface from the seed layer grid structure 2 to the metal wire layer 3. This reduces resistance loss and further improves the photoelectric conversion efficiency of the cell.
[0032] As an optional embodiment, the cell substrate 1 includes one or more of PERC cells, TOPCon cells, HJT cells, and IBC cells.
[0033] As an optional embodiment, the seed layer grid structure 2 and the metal wire layer 3 are connected and fixed by welding or conductive adhesive material, and a conductive connection is formed between the seed layer grid structure 2 and the metal wire layer 3, which is beneficial to the conduction of current.
[0034] As an optional embodiment, the metal wire layer 3 includes metal wires arranged in parallel and / or vertically.
[0035] As an optional embodiment, the metal wire layer 3 includes a plurality of parallel metal wires.
[0036] As another optional embodiment, the metal wire layer 3 is in the form of a mesh, which includes multiple metal wires arranged in a crisscross pattern.
[0037] As an optional embodiment, the equivalent diameter of the metal wires in the metal wire layer 3 is 5-70 μm. Preferably, the equivalent diameter of the metal wires is 10-30 μm, which allows for efficient current conduction while minimizing the light-blocking area.
[0038] As an optional embodiment, the cross-section of the metal wires in the metal wire layer 3 includes one or more of the following: triangle, circle, and rectangle.
[0039] As an optional embodiment, the main material of the metal wires in the metal wire layer 3 includes one or more of oxygen-free copper and pure copper.
[0040] As an optional embodiment, the surface of the metal wires in the wire layer 3 is coated with a tin-based alloy coating. The tin-based alloy coating is a material composed of tin and other elements, including one or more of bismuth, lead, antimony, and silver. The tin-based alloy coating gives the metal wires a bright appearance, strong oxidation resistance, and excellent solderability, facilitating the welding of the seed layer grid structure 2 and the wire layer 3, and also improving the reflectivity of the metal wire surface.
[0041] As an optional embodiment, the surface of the metal wires in the metal wire layer 3 has high reflectivity to reflect more light to the surface of the solar cell, thereby improving light utilization. The surface of the metal wires can be chemically polished to achieve a bright effect, thus giving the surface of the metal wires high reflectivity.
[0042] As an optional embodiment, the primary material of the first gate layer 21 includes one or more of nickel, titanium, tungsten, cobalt, tantalum, nickel-tungsten alloy, nickel-cobalt alloy, titanium-tungsten alloy, and nickel-titanium alloy. These metals possess excellent electrical conductivity, enabling effective current conduction.
[0043] As an optional embodiment, the main material of the second gate layer 22 includes one or more of tin and tin-bismuth alloy. The second gate layer 22 serves two purposes: firstly, it protects the first gate layer 21; secondly, tin and tin-bismuth alloy can melt and fill the space between the first gate layer 21 and the metal wire layer 3 during the soldering process, making the connection between the first gate layer 21 and the metal wire layer 3 tighter, which is more conducive to current conduction.
[0044] The method for preparing solar photovoltaic cells provided in this embodiment includes:
[0045] First, patterned grooves are generated on the front and back sides of the battery cell substrate 1. These patterned grooves can be obtained by methods such as laser film opening, mask etching, and paste etching.
[0046] Next, a first gate line layer 21 and a second gate line layer 22 are sequentially covered in the patterned groove to form a seed layer gate line structure 2. The preparation method of the seed layer gate line structure 2 includes one or more of electroplating, chemical plating, magnetron sputtering, and vapor deposition.
[0047] Finally, a metal wire layer 3 is superimposed on the seed layer grid structure 2, and the seed layer grid structure 2 and the metal wire layer 3 are fixed together by welding or conductive adhesive material to form a photovoltaic cell structure with superimposed grid lines and metal wires.
[0048] As described above, the solar photovoltaic cell provided in this embodiment completely abandons expensive silver raw materials and instead uses metals with excellent conductivity, such as nickel, as the seed layer, which reduces the series resistance of the cell and reduces material costs. In addition, a metal wire layer 3 with extremely high surface reflectivity is covered on the seed layer. The seed layer grid structure 2 and the metal wire layer 3 are fixed to each other and form a conductive connection through conductive connecting materials, which completely avoids the conduction of current in the sub-grid line parallel to the cell surface. Instead, the current is only conducted in the direction perpendicular to the cell surface from the seed layer grid structure 2 to the metal wire layer 3, which reduces resistance loss and further improves the photoelectric conversion efficiency of the cell. In addition, using the metal wire layer 3 instead of silver grid lines can reduce the shading area of the photovoltaic module, which is beneficial to improving the output power of the photovoltaic module.
[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A solar photovoltaic cell, characterized in that, It includes a solar cell substrate (1), a seed layer grid structure (2), and a metal wire layer (3), wherein: The front and back sides of the battery cell substrate (1) are respectively covered with a seed layer grid structure (2), and the seed layer grid structure (2) includes a first grid layer (21) and a second grid layer (22) stacked sequentially in a direction away from the battery cell substrate (1). The metal wire layer (3) covers the seed layer grid structure (2).
2. The solar photovoltaic cell according to claim 1, characterized in that, The metal wire layer (3) includes metal wires arranged in parallel and / or vertically.
3. The solar photovoltaic cell according to claim 1, characterized in that, The equivalent diameter of the metal wires in the metal wire layer (3) is 5-70 μm.
4. The solar photovoltaic cell according to claim 1, characterized in that, The cross-section of the metal wires in the metal wire layer (3) includes one or more of the following: triangle, circle, and rectangle.
5. The solar photovoltaic cell according to claim 1, characterized in that, The main materials of the metal wires in the metal wire layer (3) include one or more of oxygen-free copper and pure copper.
6. The solar photovoltaic cell according to claim 1, characterized in that, The surface of the metal wires in the metal wire layer (3) is coated with a tin-based alloy.
7. The solar photovoltaic cell according to claim 1, characterized in that, The surface of the metal wires in the metal wire layer (3) has high reflectivity.
8. The solar photovoltaic cell according to claim 1, characterized in that, The main materials of the first gate layer (21) include one or more of nickel, titanium, tungsten, cobalt, tantalum, nickel-tungsten alloy, nickel-cobalt alloy, titanium-tungsten alloy, and nickel-titanium alloy.
9. The solar photovoltaic cell according to claim 1, characterized in that, The main material of the second gate layer (22) includes one or more of tin and tin-bismuth alloy.
10. The solar photovoltaic cell according to any one of claims 1 to 9, characterized in that, The seed layer grid structure (2) and the metal wire layer (3) are connected and fixed by welding or conductive adhesive material.