Researchers investigated thermal aging in silver-coated copper electrodes for heterojunction solar cells, finding that silver-copper interdiffusion significantly increases contact resistance and degrades electrical performance. The study links microstructural evolution to a shift from sintering-enhanced conductivity to defect-driven network breakdown, providing guidance for improving long-term metallization reliability.
Researchers from the East China University of Science and Technology have investigated degradation mechanisms in low-silver electrodes used in heterojunction (HJT) solar cells, with the aim of developing design guidelines for manufacturing cost-competitive and high-efficiency photovoltaic modules.
“Our study systematically investigates the thermal aging behavior of silver (Ag)-coated copper (CU) electrodes in heter solar cells, revealing significant increases in contact resistance due to interdiffusion between the Ag and Cu layers,” corresponding author Xiaojun Ye told pv magazine. “It clarifies the underlying degradation mechanisms and provides important guidance for the design of cost-effective and reliable metallization strategies for HJT solar modules.”
The research was based on the premise that the thermal aging behavior of silver-coated copper electrodes is still not fully understood, particularly for thin Ag shells used in commercial pastes. With this in mind, the scientists investigated, in particular, degradation under accelerated aging, linking microstructural evolution and interdiffusion to electrical performance and long-term reliability.
