Photovoltaic modules are mainly composed of the following parts:

1. Battery Cells
   Battery cells are the core components of photovoltaic modules, and their function is to directly convert solar energy into electricity. Common types of battery cells on the market currently include monocrystalline silicon battery cells, polycrystalline silicon battery cells, and thin-film battery cells, etc. Monocrystalline silicon battery cells have a relatively high conversion efficiency, but the cost is relatively high; polycrystalline silicon battery cells have a lower cost and a considerable efficiency; thin-film battery cells have the characteristics of good flexibility and excellent performance in low light conditions.
   For example, in large-scale solar power stations, efficient monocrystalline silicon battery cells are often adopted to increase the total power generation; while in some distributed photovoltaic power generation projects that are more sensitive to costs, polycrystalline silicon battery cells are a more common choice.
2. Glass Panel
   It is located on the outermost layer of the photovoltaic module, playing the role of protecting the battery cells, transmitting light, and withstanding the influence of the external environment. Ultra-white tempered glass is usually adopted, which has good light transmittance and mechanical strength and can effectively resist the invasion of harsh weather such as sandstorms, rain, and snow.
3. EVA Film
   The EVA film is sandwiched between the battery cells and the glass panel, as well as between the battery cells and the backsheet, and is used for bonding and encapsulation. It has good flexibility and weather resistance, which can ensure the stability of the module during long-term use.
4. Backsheet
   The backsheet is located on the back of the module, and its main role is to protect the battery cells from erosion by water vapor, oxygen, etc., and at the same time play an insulating role.
5. Frame
   The frame is generally made of aluminum alloy materials and is used to fix and protect the module, enhance the mechanical strength of the module, and facilitate installation and transportation.
   These constituent parts of photovoltaic modules collaborate with each other to jointly convert solar energy into clean and renewable electricity. With the continuous advancement of technology, the composition of photovoltaic modules is also constantly optimized and innovated to improve efficiency, reduce costs, and make greater contributions to our energy transformation and environmental protection.