ABSTRACT Scaling flexible perovskite solar cells (F‐PSCs) into high‐performance large‐area modules remains a fundamental challenge due to intrinsic defects and mechanical fragility in perovskite films. We innovatively introduce D‐trehalose (DTA) as a multi‐functional modulator. DTA's unique flexible disaccharide backbone and multi‐hydroxyl structure enable the construction of a dynamic and continuous hydrogen‐bonding network within the perovskite film, which not only regulates crystallization kinetics over large areas but also induces collective lattice polarization. This polarization stabilizes the perovskite framework, releases residual stress, and effectively suppresses ion migration and defect recombination across scalable devices. As a result, we fabricate large‐area flexible perovskite solar modules, achieving a certified efficiency of 18.86% (active area: 619.9 cm 2 ) with a geometric fill factor of 96.95%. Remarkably, the modules retain 92.76% of their initial efficiency after 10 000 bending cycles (radius: 4.9 cm), demonstrating unprecedented scalability and durability. This work provides a molecular crosslinking approach to decouple efficiency and flexibility constraints, advancing the commercialization of high‐performance flexible photovoltaics.
Ma et al. (Sat,) studied this question.