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

Abstract

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.