the glass on the solar panel is a kind of low-iron tempered glass, also known as white glass, with a common thickness of about 3.2 mm. the light transmittance is over 90% in the wavelength range of the solar cell's spectral response (320-1100nm). the infrared light of 1200nm has a higher reflectivity. solar panel glass has the advantages of resistance to ultraviolet radiation and ensuring that the light transmittance does not decrease.
the toughening performance of solar panel glass must meet the national standard gb9963-88, and the impact resistance of the packaged module must meet the performance indicators specified in the national standard gb9535-88 ground silicon solar cell environmental test method before it can be put into use.
because the solar cell module is laminated by 5 layers, the surface glass and the original module are glued together by eva. eva is a hot-melt adhesive with a thickness between 0.4 mm and 0.6 mm. the surface is flat and the thickness is uniform, with cross-linking agent inside. eva is non-sticky and anti-sticky at room temperature. after a certain heating and pressure adjustment, it will melt and bond, cross-link and solidify, and become completely transparent.
the cured eva can withstａnd atmospheric changes and is elastic. it covers and underlays the cell, encapsulates it, and combines it with the upper protective material glass and the lower protective material backplane (tpt, bbf, etc.) using a vacuum layer the pressing technology is integrated. on the other hand, it can increase the light transmittance of the glass after being bonded to the glass, play an anti-reflection effect, and have a gain effect on the output of the solar panel. the original solar panel is very thin, so it is easy to damage the fragile cell if you just take out the glass.