I know. AIKO has been using copper in their BC cells, and LONGi is making the transition. Many TOPCon cell manufacturers are using silver-coated copper pastes

I know. AIKO has been using copper in their BC cells, and LONGi is making the transition. Many TOPCon cell manufacturers are using silver-coated copper pastes, but full copper metallization is unlikely to happen in the next year or two.