Under the impetus of the "dual carbon" goals, photovoltaic power generation is rapidly emerging as a dominant force in promoting the green and low-carbon transition. As the core component of photovoltaic power generation systems, a photovoltaic module refers to the smallest indivisible photovoltaic cell assembly device that has encapsulation and internal connections and can independently provide direct current. It is composed of eight core materials. Today, let's delve into the eight main materials of photovoltaic modules.
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Photovoltaic Glass
Photovoltaic glass, considered the first line of defense for photovoltaic modules, is a special type of soda-lime silicate glass, typically presented in low-iron tempered or semi-tempered forms. It not only requires high light transmittance but also strong impact resistance. The high transparency of quality photovoltaic glass effectively enhances the light absorption efficiency of photovoltaic cells, while its high mechanical strength ensures the stability and durability of the module in harsh environments. -
Encapsulant Film
The photovoltaic encapsulant film, located on both the top and bottom sides of the cell, is used not only to firmly bond the cell to the glass and backsheet but also to provide encapsulation protection, safeguarding the cell circuit from external environmental interference and extending the module's service life. High-quality encapsulant films can effectively enhance the module's light transmittance, thereby improving the power generation efficiency of photovoltaic modules. -
Photovoltaic Cell
The cell is the core power generation unit of the photovoltaic module, tasked with the important mission of converting solar energy into electrical energy. Its technological route and process level directly affect the power generation efficiency and service life of the photovoltaic module. Through the precise arrangement of series and parallel connections, cells ultimately form a complete module with a certain rated power and voltage. The working principle of photovoltaic cells follows the photovoltaic effect, utilizing light to excite the generation of electron-hole pairs and achieving carrier separation through the electric field of the P-N junction, ultimately forming a stable current output, which is crucial for the overall power generation capability of the module. -
Backsheet
The backsheet, located on the back of the photovoltaic module, primarily serves to protect the cell and encapsulant film from erosion by harsh environmental factors such as humidity, heat, and ultraviolet rays. Backsheets are generally divided into two types: fluorinated and non-fluorinated, with white backsheets offering unique advantages. They can scatter light, increasing the cell's light absorption efficiency, effectively reduce the module's operating temperature, enhance insulation performance, and comprehensively improve the module's stability and reliability. -
Frame
The photovoltaic frame is installed on the glass extension, mainly used for fixing and sealing the solar cell module, facilitating the transportation and installation of photovoltaic modules. The installation of the frame protects the glass edges; the combination of aluminum alloy and silicone enhances the module's sealing performance; significantly increases the overall mechanical strength of the module; facilitates the installation and transportation of the module; and serves as the connecting carrier between the module and the bracket, achieving optimal load-bearing capacity through fixation. -
Ribbon
Photovoltaic ribbon, also known as tin-coated copper ribbon, is a composite conductive material formed by coating a tin-based solder on the surface of a copper strip. It is used in the series or parallel connection of photovoltaic cells, playing a role in collecting and conducting current, and is an important material in the welding process of photovoltaic modules. Ribbons are divided into interconnect ribbons and bus ribbons. Interconnect ribbons are used to connect photovoltaic cells, collecting and transmitting the current from photovoltaic cells; bus ribbons are used to collect the current generated by the cell strings and lead it out to the junction box. -
Silicone
Silicone is a key material for sealing and connecting photovoltaic modules, commonly used for bonding the frame to the glass, and the junction box to the backsheet (or glass). Its main function is to prevent air and moisture from entering the module, ensuring the module's stability over long-term use. Depending on the application site, silicone is divided into sealant and potting compound. Sealant is used for sealing the frame groove and the bottom of the junction box, while potting compound is mostly used inside the junction box to protect the circuit from moisture and oxidation. -
Junction Box
The junction box is an important electrical accessory of the photovoltaic module, responsible for connecting the electrical energy generated by the cells to the external circuit. The junction box is usually equipped with key components such as diodes, sealing rings, and heat dissipation devices, ensuring stable current output and preventing reverse current from damaging the cells. Its design must not only meet electrical and mechanical performance requirements but also possess good heat resistance, corrosion resistance, and weather resistance to adapt to various environmental conditions.