An Interconnection Strategy for Thermally Sensitive Solar Cells Employing Electrically Conductive Tape

The electrical interconnection of high‐efficiency silicon heterojunction and perovskite–silicon tandem solar cells is constrained by their sensitivity to elevated processing temperatures, which precludes the use of conventional solder‐based interconnections. As a low‐temperature alternative, electrically conductive tapes (ECTs) offer a promising solution; however, their applicability in photovoltaic modules has been underexplored. This study evaluates the feasibility of commercially available ECTs as solder‐free interconnection materials for silicon heterojunction solar cells. To assess their performance, we characterized the effects of lamination pressure and temperature on adhesion and electrical contact resistance, followed by rigorous long‐term stability testing under damp heat (2000 h) and thermal cycling (200 cycles) per IEC 61215 standards. Anisotropic ECTs demonstrated low and stable contact resistances, comparable to those of low‐melting‐point solders, while also exhibiting robust mechanical durability. Among the tested materials, ECT‐2 exhibited the highest adhesion strength, achieving a peak value of 1.8 N/mm, whereas ECT‐3 provided the lowest and most consistent contact resistance. Specifically, ECT‐3 maintained contact resistance values in the range of 10 −3 –10 −2 mΩ·cm 2 throughout both damp heat and thermal cycling tests, matching the performance of soldered interconnections. Silicon heterojunction modules utilizing ECT‐based interconnections showed superior stability during accelerated aging, with efficiency losses below 5%, outperforming both isotropic tapes and soldered references. Furthermore, ECTs enabled effective electrical connections in perovskite–silicon heterojunction tandem solar cells, facilitating solder‐free interconnection without the need for thermal curing. An encapsulated perovskite–silicon tandem cell with an effective area of 1 × 1 cm 2 achieved an efficiency of 28.6%, with unchanged open‐circuit voltage ( V oc ) and fill factor (FF). These findings underscore the potential of ECTs as a scalable, low‐temperature interconnection solution for next‐generation photovoltaic technologies.