Challenges & Solutions in PV Interconnection

Photovoltaic module interconnection is facing new constraints due to emerging low-temperature cell technologies, regulatory restrictions concerning lead, and rising silver demand. This study addresses these challenges by evaluating scalable, lead-free, and silver-reduced for industrially scalable interconnection approaches. Experimentally validated solutions include lead-free SnBiAg0.4 solder alloy for low-temperature application such as silicon heterojunction solar cells (SHJ), SAC305 and SnCu solder alloys for high-temperature applications such as passivated emitter and rear cell (PERC) or tunnel oxide passivated contact (TOPCon) solar cells, and silver-reduced ECAs for sensitive solar cell technologies. A full-format module with Cu-plated TOPCon solar cells and lead-free solder demonstrated reliable process integration and performance. The resulting roadmap outlines practical material-process combinations to support compliant and future-proof PV production.