Glass powder for TOPCon crystalline silicon solar cell main grid slurry and preparation method thereof

The invention discloses glass powder for TOPCon crystalline silicon solar cell main grid slurry and a preparation method thereof.The glass powder is obtained by mixing glass frits A and B obtained after cold rolling according to the mass ratio of (1.5-2): 1 and then conducting secondary melting and cold rolling, the glass frits A comprise PbO, SiO2, B2O3, Li2O, Na2O and the like, the glass frits B comprise Bi2O3, SiO2, AgNO3, B2O3, Li2O, Na2O and the like, and the glass frits A, B and B are mixed according to the mass ratio of (1.5-2): 1. Wherein distilled water is added during batching of the glass frit B to enable AgNO3 to be fully combined with other oxides, the glass frit B is dried to be in a viscous state to be fired, and AgO in glass is reduced into silver microcrystals by utilizing a laser enhanced contact optimization technology in the sintering process, so that the electrical property of a main grid line is improved, the damp heat attenuation of a printed battery piece is reduced, the reliability of