Key takeaways:
Solamet's silver-lean product portfolio progresses from Ag-Ni to Ag-coated Cu and pure Cu pastes
These products target the current mainstream TOPCon, BC, and upcoming hybrid passivated BC technologies
The pure copper pastes are designed for processing without inert or reducing atmospheres
China-based metallization paste supplier Solamet offers its latest low-silver and silver-free metallization portfolio targeting TOPCon, back-contact (BC), and heterojunction (HJT) solar cell technologies. The company presented these products at the TaiyangNews Solar & Battery Procurement Briefing.China (SSPB.C) 2026, held in collaboration with SNEC in Shanghai a day before the event.
Solamet introduced its PV3NN for the front side and PV6NN for the rear for both TOPCon and tunnel oxide back contact (TBC) cells. In these paste formulations, silver is partially replaced by nickel to reduce its consumption while maintaining cell performance. These formulations are available with nickel content ranging from 5% to 15%, depending on the customer's requirement.
The company also offers a solution for further reduction in silver that involves two-step printing on the rear side, first a silver seed layer using PV6NS, followed by a silver-coated copper paste using PV43T. The silver layer first establishes the electrical contact with the cell, and the silver-coated copper paste layer provides the electrical conductivity. The silver content in the silver-coated copper paste is about 20%.
The final solution, which further reduces silver, replaces the silver-coated copper paste with pure copper paste. The company’s solution to this is the PV46 series, including PV46B for TOPCon, PV46D for TBC, and PV46A for HJT, heterojunction-BC, and hybrid passivated BC (e.g., LONGi’s HIBC). To overcome the oxidation issue of copper, these paste solutions use an anti-oxidation design that can also enable cell processing without requiring an inert or reducing atmosphere. The company claims that with its pure copper paste solution, cell manufacturers can use existing thermal processing equipment for the post-metallization steps.
