The thin film deposited on the surface of the solar cell generally includes the following functional components:
1. Light absorption layer (absorbing layer): The light absorption layer of the solar cell is the most critical. thin film component, which can absorb light energy and convert it into electrical energy. Common light-absorbing layer materials include silicon (Si), copper-indium-gallium selenide (CIGS), copper-indium-sulfur selenide (CISS), etc.
2. Transparent conductive layer: The transparent conductive layer is used to collect the current generated by the photovoltaic cell and transmit it to the external circuit. Common transparent conductive layer materials include tin oxide (SnO2) and indium tin oxide (ITO).
3. Light-reflecting layer (rear reflector): the light-reflecting layer is located between thee light-absorbing and substrate to improve light utilization. It is usually made of metal or metal oxide, such as aluminum (Al), silver (Ag) or aluminum foil (Aluminum Foil).
4. Passivation layer: The battery protective layer is used to protect the surface of the photovoltaic cell from damage caused by the external environment, while reducing the contact between the photovoltaic cell and environmental impurities. Common battery protective layer materials include aluminum oxide (Al2O3), silicon nitride (Si3N4), etc.
5. Encapsulation layer: The encapsulation layer is used to protect photovoltaic cells from external environments such as humidity, oxygen and dust. Common materials for encapsulation layers include polymeric materials, such as epoxy resin (Epoxy Resin), polymethacrylate methyl (PMMA), etc.
Advantages of power generation
Thin film power generation technology has the following advantages: flexibility, light weight, good low light performance, adjustable color and shape in plastic. Public information shows that the efficiency of gallium arsenide flexible solar cells is 8% higher than that of global mass-produced monocrystalline silicon technology and 10% higher than that of polycrystalline silicon. In the same area, the efficiency of flexible gallium arsenide solar cells can. reach 2 times that of ordinary flexible solar cells ~ 3 times.
Scope of application
Thin film energy production allows humans to directly use sunlight like green plants. Thin film energy production can be understood as “artificial chlorophyll”. Energy production technologyThin film technology can be widely used in various fields such as distributed power generation, 3C mobile products, wearable devices, solar energy vehicles, solar drones and satellites.
Industrial development status
Recently, after measurements and certifications by the US Department of Energy and the US National Renewable Energy Laboratory ( NREL), Alta arsenic. The conversion rate of double junction cells to gallium reached 31.6%, once again setting a new world record. In 2023, the American company Alta was acquired by the Hanergy Holding Group of China
On January 26, 2023, the American thin film company MiaSolé announced that its copper thin film flexible solar cell module , indium and gallium selenide FLEX-02 had obtained IEC61646, IEC61730 and UL1703 certification, as well as UL790 certification ofhighest fire protection (class A). (Note: IEC stands for International Electrotechnical Commission and UL stands for Underwriters Laboratories) This module is the flexible and lightweight thin film solar cell module with the highest conversion efficiency on the market, with a mass production conversion rate of 16%. Applications for this high power density cellular module range from rooftop installations, tank and landfill lining, transportation applications such as cars and trucks, to off-grid products and a variety of consumption. The module is produced in Hanergy factory in Heyuan, Guangdong, which has passed UL, IEC and ISO9001 certifications. For customers, FLEX-02 components offer many advantages.
First of all, it is very light, with a mass of less than 0.7 pounds per square foot (equivalent to a weight of less than 3.5 kilograms per square meter), and can be installed on roofs or others. building structures that cannot support traditional glass-based solar panels. Secondly, since the component can be directly attached to the surface of the building or object structure, it will not cause leakage or damage to the building or object at the same time; The component is very beautiful and can be integrated into roofs, vehicles and other building structures, allowing it to maintain its original appearance without the use of unsightly supports. In addition, FLEX-02 components are thin, flexible and small, so they have excellent resistance to wind and earthquakes. In comparison, traditional rack-mounted panels are bulky and easily damaged by hurricanes or earthquakes. The MiaSolé company was bought by the Chinese group Hanergy Holding in 2023.