Engineers at the Russian company Hevel, which specializes in the production of solar panels in Novocheboksarsk (Chuvash Republic), together with scientists from its own Scientific and Technical Center, introduced a new conductive paste into the production cycle for forming the current-collecting grid of silicon photovoltaic converters. The key difference of the development was the partial replacement of expensive silver with copper, which made it possible to significantly reduce production costs without compromising electrical performance.
Previously, the paste composition contained 100% silver, but now its content has been reduced to 60%. The new formula contains microscopic spheres up to 4 microns in diameter, inside which there is a copper core coated with a layer of silver. This innovation prevents copper oxidation, while the main characteristics of the product remain unchanged.
According to Igor Shakhray, Chairman of the Board of Directors of Hevel Group, in the near future the company intends to reduce the share of silver in the paste to 10%, continuing to optimize materials to improve the economic efficiency of solar modules.
As industry experts note, reducing the silver content in photovoltaic elements is a global trend driven by the growth in the specific consumption of this precious metal as technological generations of solar cells change. According to the Chinese manufacturer Changzhou Fusion New Material, the use of composite copper-silver pastes in the production of heterojunction elements makes it possible to reduce silver consumption by 2.5-3 times.