Introduction to Materials of Photovoltaic Modules
What are the raw materials of photovoltaic (PV) modules?PV materials refer to materials capable of converting solar energy directly into electrical energy. PV modules are primarily composed of eight key materials:
Aluminum Alloy Frame
Protects the edges of the glass.
Enhances sealing performance when combined with silicone.
Significantly improves the overall mechanical strength of the module.
Facilitates installation and transportation of the module.
Acts as the connecting carrier between the module and its mounting structure, optimizing load resistance and improving the mechanical stability of the solar power system from unit level to integration.
Silicone
Used for bonding and sealing the laminated glass of PV modules.
Bonds the junction box and backsheet.
Enhances UV resistance of the PV modules.
Tempered Glass
Must be clean, moisture-free, and not touched directly by hand on both surfaces.
Provides structural support for PV modules and enhances load-bearing capacity.
Features include light transmission, anti-reflective transparency, and resistance to water, gas, and corrosion.
EVA Encapsulation Film
A copolymer of ethylene and vinyl acetate, functioning as a hot-melt adhesive.
Encapsulates the solar cells to protect their electrical properties from external environmental impacts.
Improves the light transmittance of the module and bonds the cells, tempered glass, and backsheet together.
Enhances electrical performance output of the solar cells while providing adequate bonding strength.
Photovoltaic Ribbon
Interconnect Ribbon: Connects the solar cells within the module, conducting electricity and collecting current from the cells.
Bus Ribbon: Connects the cell strings within the module, transferring the electrical current generated by the cells to the junction box.
Solar Cells
Devices that directly convert light energy into electrical energy using semiconductor materials.
When exposed to sunlight, electron-hole pairs are generated.
The electric field in the P-N junction separates these pairs, and the separated electrons and holes are collected by electrodes to create an electrical current.
Backsheet
Serves as a protective encapsulation material on the back of the module.
Common materials include TPX, KPX, and PET.
Enhances the module's resistance to aging and corrosion, prolonging its lifespan.
White backsheets scatter light entering the module, improving light absorption efficiency.
High infrared emissivity reduces operating temperature, and the backsheet also improves insulation performance.
Junction Box
Installed on the module to transfer current.
Must exhibit excellent electrical properties while meeting environmental requirements for electrical, mechanical, thermal, corrosion, and weather resistance.
Should not pose any risks to users or the environment.
The above is an introduction to the eight main materials that compose photovoltaic modules, as detailed by Hengyuan Tai.