Monocrystalline silicon solar cells are solar cells made from high-purity monocrystalline silicon rods and are currently one of the fastest-developing types of solar cells. The structure and manufacturing process of monocrystalline silicon solar cells are now standardized, and the products are widely used in space and on the ground.
The components and functions of monocrystalline silicon solar cells:
1. Tempered glass: Its function is to protect the main power generation unit (such as solar cells). There are requirements for its selection. First, the light transmittance must be high (generally above 91%). Second, it must be ultra-white tempered.
2. EVA: Used to bond and fix tempered glass and the main power generation components (such as solar cells). The quality of transparent EVA material directly affects the lifespan of the module. EVA exposed to air is prone to aging and yellowing, which affects the light transmittance of the module and thus the power generation quality. In addition to the quality of the EVA itself, the lamination process of the module manufacturer also has a great impact. For example, if the EVA adhesiveness is not up to standard, or if the bonding strength between EVA and tempered glass and backsheet is insufficient, it will cause the EVA to age prematurely and affect the lifespan of the module.
3. Solar Cells: Their main function is to generate electricity. The mainstream types in the market are crystalline silicon solar cells and thin-film solar cells, each with its own advantages and disadvantages. Crystalline silicon solar cells have relatively low equipment costs, but high consumption and cell costs, and also high photoelectric conversion efficiency. Thin-film solar cells are more suitable for generating electricity outdoors in sunlight. While their equipment costs are relatively high, their consumption and cell costs are very low. Their photoelectric conversion efficiency is slightly more than half that of crystalline silicon solar cells, but they perform very well in low-light conditions and can generate electricity even under ordinary lamplight, such as the solar cells on calculators.
4. Backsheet: Its function is to seal, insulate, and waterproof (generally made of materials such as TPT and TPE). It must be resistant to aging. Module manufacturers offer a 25-year warranty. Tempered glass and aluminum alloy are generally fine. The key is whether the backsheet and silicone can meet the requirements.
5. Aluminum alloy protective laminate: provides a certain degree of sealing and support.
6. Junction Box: Protects the entire power generation system and acts as a current transfer station. If the module is short-circuited, the junction box will automatically disconnect the short-circuited battery string to prevent the entire system from burning out. The most critical part of the junction box is the selection of diodes. The corresponding diodes are different depending on the type of battery cells in the module.
7. Silicone: Used for sealing, sealing the junction between components and aluminum alloy frames, and between components and junction boxes. Some companies use double-sided tape or foam to replace silicone, but silicone is widely used in China because it is simple, convenient, easy to operate, and has a very low cost.
