Lab-to-Fab development and long-term greenhouse test of stable flexible semitransparent organic photovoltaic module

The Lab-to-Fab transfer from cell to large-area flexible semitransparent organic photovoltaic (OPV) module by the slot-die coating based on halogen-free host solvent and under ambient air environment is developed. The bulk heterojunction structure (BHJ) and formation mechanism of slot-die-coated active layer on flexible substrate are different from those usually reported. The relationship among processing, film thickness/BHJ morphology, transmittance and performance for the slot-die-coated module, and the optimum strategy are studied in this article. The flexible semitransparent modules with active areas of 45 and 22.5 cm² have the average visible transmittance of 21.3%–16.7%. The corresponding average power conversion efficiency (PCE) values are 4%–6.2%. The highest PCE can achieve 7.8%. Compared to all large-area flexible semitransparent slot-die-coated OPV modules reported with PCEs (usually ≤5%), the modules prepared here have the best PCE. The electric behavior and stability of these OPV modules and a Si-PV panel under the greenhouse test are studied. Among the stability data (usual T₈₀ lifetime ≤100 days) reported for semitransparent flexible OPV modules under greenhouse test, the T₈₀ lifetime of the OPV modules prepared here can reach 200 days and also remain the highest PCE with the least burn-in loss.