Enabling Outdoor Operation of Tin–Lead Perovskite Solar Cells via Lamination-Based Encapsulation

Tin–lead (Sn–Pb) perovskites are essential narrow-bandgap absorbers for two-terminal perovskite–perovskite tandem solar cells, yet their extreme air sensitivity has confined stability studies indoors, leaving real-world durability unexplored. Here, we substantially lower this barrier using industrially relevant, lamination-based encapsulation that enables, to our knowledge, the first outdoor demonstration of Sn–Pb devices. Combining polyisobutylene edge sealing with polyolefin elastomer encapsulation, we demonstrate that the lamination process is highly compatible with Sn–Pb devices, causing negligible performance loss while preserving optoelectronic quality during short-term air exposure. Under package-oriented accelerated aging, epoxy-based encapsulation fails rapidly, whereas the lamination-based package remains intact. Outdoors under tandem-relevant filtered illumination, lamination-encapsulated devices retain ∼80% of initial efficiency after 12 days, while epoxy-encapsulated devices lose all output within 6 days. By adapting manufacturable module packaging to Sn–Pb devices, this work enables their realistic field evaluation, marks a critical step toward deployable all-perovskite tandems, and strengthens confidence in their commercial viability.