23 METAL WRAP THROUGH SILICON HETEROJUNCTION SOLAR CELLS - A SIMPLE TECHNOLOGY INTEGRATING HIGH PERFORMANCE CELL AND MODULE TECHNOLOGIES

摘要

Metal wrap through silicon heterojunction (MWT-SHJ) cells and modules combine the positive benefits of both underlying technologies: namely high Voc, higher Jsc and higher FF maintained before and after module encapsulation. We obtained 22.0% efficiency with low temperature Ag paste metallisation of front side and more than 23% on copper plated front metallisation. Voc values above 730 mV have been achieved, demonstrating that this architecture maintains the exceptional passivation of SHJ devices. The MWT cell and module structure offers even greater advantages when applied to SHJ solar cells: i) front side Ag consumption reduction up to a factor two; ii) low temperature cell interconnection concurrently with the encapsulation. Our record MWT-SHJ solar cells and modules are manufactured using industrially proven tools. The metallisation choice gives ample room to manufacturers to optimise based on internal cost structure and business strategy.