What Are Photovoltaic Cells or Solar Cells Made Of
Introduction
Photovoltaic cells, also known as solar cells, are devices that convert sunlight into electricity. They are a key component of solar panels and are widely used in renewable energy systems. But what exactly are photovoltaic cells made of? In this article, we will explore the materials and components that make up these important devices.
Semiconductor Materials
Silicon
The most common material used in photovoltaic cells is silicon. Silicon is a semiconductor, which means it can conduct electricity under certain conditions. In a photovoltaic cell, silicon is doped with small amounts of other elements to create a p-n junction, which is essential for the functioning of the cell.
Thin-Film Photovoltaic Cells
In addition to silicon, thin-film photovoltaic cells are made of other semiconductor materials such as cadmium telluride (CdTe), copper indium gallium selenide (CIGS), and amorphous silicon. These materials are used to create thin layers of photovoltaic cells, which are more flexible and less expensive to produce than traditional silicon-based cells.
Metal Contacts
Front and Back Contacts
Photovoltaic cells have metal contacts on the front and back to allow for the flow of electricity. The front contact is usually made of a grid of thin metal wires, while the back contact is typically a thin film of metal.
Busbars and Ribbons
In addition to the front and back contacts, photovoltaic cells also have busbars and ribbons that connect multiple cells together to form a solar panel. These components are typically made of copper or other conductive metals.
Encapsulation Materials
Encapsulant
To protect the semiconductor materials and metal contacts from environmental factors, photovoltaic cells are encapsulated with a clear, durable material such as ethylene-vinyl acetate (EVA) or Tedlar. This encapsulant also helps to trap sunlight within the cell, increasing its efficiency.
Backsheet
The backsheet of a photovoltaic cell is typically made of a polymer material that provides additional protection from moisture, UV radiation, and other potential sources of damage.
Conclusion
In conclusion, photovoltaic cells are made of a combination of semiconductor materials, metal contacts, and encapsulation materials. These components work together to capture sunlight and convert it into electricity, making solar cells a crucial technology for clean and sustainable energy production. As technology advances, new materials and designs are constantly being developed to improve the efficiency and durability of photovoltaic cells.