JP-7855729-B2 - Manufacturing method for solar power generation modules

Inventors

• シェン イレイ
• マルコ シュテルツェル

Assignees

• 中建材玻璃新材料研究院集団有限公司

Dates

Publication Date

20260508

Application Date

20231124

Claims (7)

1. A method for manufacturing a solar power generation module, The aforementioned solar power generation module is Front electrode and, The buffer layer below the front electrode, The absorber below the buffer layer, The back electrode below the absorber, A group of protrusions formed on the front electrode, wherein each group of protrusions includes at least two protrusion structures, at least two rows of protrusion groups form a set of protrusion arrangements, a gap is formed between two adjacent groups of protrusions to limit the width of the liquid to be applied, and a height difference is formed between the top of the protrusion and the upper surface of the front electrode to limit the thickness of the liquid to be applied; Includes, The method for manufacturing the aforementioned solar power generation module is: A step of forming the group of protrusions using laser light, wherein the laser light is absorbed at the interface between the buffer layer and the absorber, and the group of protrusions protrudes upward from the interface between the buffer layer and the absorber and penetrates the front electrode. A method for manufacturing a solar power generation module, characterized by including the following:
2. The method for manufacturing a photovoltaic module according to claim 1, characterized in that the wavelength of the laser light is greater than the wavelength corresponding to the optical band gap of the material of the front electrode and less than the wavelength corresponding to the optical band gap of the material at the interface between the buffer layer and the absorber .
3. The aforementioned arrangement of protrusions is one of the following: a juxtaposed arrangement , a staggered arrangement , or an irregular arrangement. A method for manufacturing a solar power generation module according to claim 1 or 2 .
4. A method for manufacturing a photovoltaic module according to claim 1 or 2, characterized in that the spacing between two adjacent rows of protrusion groups is greater than 10 μm in each case.
5. The method for manufacturing a solar power generation module according to claim 1 or 2, characterized in that the laser light is pulsed laser light.
6. The aforementioned solar power generation module includes one of CIGS , CdTe , or perovskite. A method for manufacturing a solar power generation module according to claim 1 or 2 .
7. A method for manufacturing a solar power generation module according to claim 1 or 2, characterized in that the liquid includes a metallic ink or a dielectric ink.

Description

This application relates to the technical field of aspect ratio optimization of metal lattices, and more specifically, to a method for optimizing the aspect ratio of metal lattices based on surface modification. Thin-film photovoltaic modules typically consist of a back electrode, absorber, buffer layer/i layer, and front electrode. To avoid high series resistance and the resulting high current loss, the module is usually designed as a series of monolithic interconnected cells, the specific structure of which is shown in Figure 1. Generally, such a cell sequence is shown in Figure 2 (a plan view of Figure 1), where the front and back electrodes are insulated at P1 and P3, and the front and back electrodes are electrically in contact at P2 for the series connection of two adjacent cells. The structural regions of P1, P2, and P3 do not generate electricity and are therefore also called the "dead areas" of the solar cell; the remaining area is called the active cell area. Figure 3 shows a monolithic connection of three separate cells, where the first and third batteries are not in contact. To optimize the power conversion efficiency of solar cells, a common approach is to increase the transmittance of the front electrode by, for example, reducing the thickness of the layer and increasing the generated photocurrent. However, this increases the sheet resistance of the front electrode, leading to increased conduction losses. To reduce such conduction losses in the front electrode, a highly conductive, narrow metal grid wire may be applied to the front electrode layer to improve its conductivity; this is known as the metallization process in photovoltaic power generation. As shown in Figure 4, because the grid wire material has low series resistance, applying a metal grid to the front electrode collects charge carriers from the front electrode material, causing a concentrated current to flow to the end of the cell. In the case of a monolithic interconnected cell, the current collected by the metal grid wire and directed toward the end of the cell is directly connected to the back electrode of the next cell via the P2 patterning line. While the above metal grid structure reduces conduction losses in the thinned front electrode and offsets the increase in series resistance, it also leads to an increase in dead area due to shading caused by the opaque grid wire above the active cell area. The shading area of the lower absorber material is defined by the width and length of the metal wire. While the length of the metal wire should not be altered to benefit from carrier collection within the wire and the thinning of the front electrode (i.e., to increase photocurrent without increasing series resistance), optimizing the width and thickness of the metal wire can reduce the seeding area, thereby increasing the photocurrent and efficiency of the solar cell. The relationship between the width and thickness of the metal wire is called the aspect ratio. The series resistance of a metal wire is determined by the specific series resistance and cross-sectional area of its constituent materials. Therefore, to improve the efficiency of solar cells, the width of the metal wire should be reduced to minimize light obstruction, while the thickness of the metal wire should be increased to prevent conduction losses. Conventionally, commercial thin-film/CIGS solar power manufacturers and their related research institutions have introduced a method called ALD (i.e., aluminum wire deposition) for depositing a metal lattice structure on the front electrode of a CIGS module. This method involves depositing an aluminum wire structure via a mask using thermal evaporation. The resulting structure is shown in Figure 5 and has the following various drawbacks. 1) Low throughput and yield due to the use of masks. 2) The high cost of this special mask for producing large-area modules. 3) High material waste due to evaporation. 4) High workload due to mask maintenance, which is crucial for the efficiency of solar cells. 5) Limitations on the width (and aspect ratio) of the metal grid wires (the openings of the mask are too narrow, smaller than several hundred micrometers, and prone to clogging during or after use). Another metallization process involves depositing metal grid lines using a screen printing method. However, screen printing is not suitable for large-area printing due to its significant technical limitations. Specifically, large printing patterns result in low deposition accuracy and poor line shape (i.e., broad lines), especially in the intermediate regions of large printing areas (e.g., >1 m² ), due to the low rigidity of the central screen (i.e., bending effect). Furthermore, printing narrow lines using screen printing requires high-quality screens (e.g., hardened and calendered stainless steel screens or knotless screens). For full-size thin-film solar cell modules (e.g., >1 m² ), high-quality large screens are extremely difficult to