Solar panels are also called solar modules and solar panels. The assembly of multiple solar cells is the core part of the solar power system and the most important part of the solar power system.
Solar cells, also known as "solar chips" or "photocells", are photoelectric semiconductor sheets that use sunlight to directly generate electricity. Single solar cells cannot be used directly as power sources. As a power source, several single crystalline solar cell must be connected in series, connected in parallel and tightly sealed into components.
1. Tempered glass: Its function is to protect the main body of power generation (such as cells), and its selection is required: the light transmittance must be high (generally more than 91%); ultra-white tempered glass.
2. EVA: used to bond and fix the toughened glass and the main body of power generation (solar cell). The quality of the transparent EVA material directly affects the life of the module, and the EVA exposed to the air is prone to ageing and yellowing, which affects the light transmittance of the module.
In addition to the quality of the EVA itself, the lamination process of the module manufacturer also has a great influence on the power generation quality of the module. For example, the adhesiveness of EVA is not up to the standard, and the bonding strength between EVA and tempered glass and backplane is not enough, which will cause EVA to age prematurely and affect the life of the components.
3. Cells: The main function is to generate electricity. The mainstream in the main power generation market is crystalline silicon solar cells and thin-film solar cells, both of which have their own advantages and disadvantages. The cost of crystalline silicon solar cells is relatively low, but the cost of consumption and cells is high. Its photoelectric conversion efficiency is also high, and it is more suitable to generate electricity in outdoor sunlight.
The relative equipment cost of thin-film solar cells is high, but the consumption and battery costs are low. Its photoelectric conversion efficiency is more than half that of crystalline silicon cells, but the low-light effect is very good, and it can also generate electricity under ordinary light, such as solar cells on calculators.
4. Backplane: function, sealing, insulating and waterproofing. Generally, TPT, TPE and other materials are used, which must be resistant to aging. Most component manufacturers have a 25-year warranty. Tempered glass and aluminum alloy are generally okay. The key is whether the backplane and silica gel can meet the requirements.
5. Aluminum alloy: The mono silicon solar panel protective laminate plays a certain role of sealing and supporting.
6. Junction box: It protects the entire power generation system and acts as a current transfer station. If the component is short-circuited, the junction box will automatically disconnect the short-circuit battery string to prevent the entire system from being burned. The most important thing in the junction box is the selection of diodes. Depending on the type of cell in the assembly, the corresponding diodes are also different.
7. Silicone: Sealing function, used to seal the junction of solar panel components and aluminum alloy frame, component and junction box. Some companies use double-sided tape and foam instead of silica gel. Silica gel is widely used in China, which is simple, convenient, easy to operate, and low cost.