Upscaling of Perovskite/c-Si tandem solar cells by using industrial adaptable processes

The perovskite material has been introduced as a novel type of wide-bandgap (WBG) light absorber in photovoltaics. Recently, perovskite/crystalline silicon (c-Si) tandem solar cells have achieved efficiencies beyond those of the silicon single-junction limit, which makes them very promising as a next-generation solar cell technology to further increase conversion efficiency. However, most of the efficiency-record tandem cell devices are those with laboratory-relevant architectures, e.g., a small active area (≤ 1cm2) on ∼250 µm thick Float-Zone (FZ) Si bottom cells and with evaporated metallization. Scaling-up of perovskite/c-Si lab tandem solar cells with industrial adaptable processes is needed to accelerate the time-to-market. In this work, we integrate the industrial compatible process for two-terminal perovskite/c- Si tandem solar cells, which includes the combinations of “screen-printed silver (SP-Ag) grids and transparent conductive oxides (TCOs)” front-electrode setup; and large area slot-die coated (SDC) WBG perovskite layer on the Czochralski (Cz) c-Si bottom cells. It is demonstrated that SP-Ag with a low thermal budget (150 °C) curing can achieve a grid resistance of 1.6 Ω/cm on and metal-to-TCO contact resistivity of 2 mΩꞏcm2. The SDC perovskite layer exhibits good homogeneity in thickness and crystallization. There was no further degradation after the additional post-printing curing step, indicating good thermal stability. Under AM 1.5G irradiation, the champion 4 cm2 perovskite/c-Si tandem solar cells have a stabilized power conversion efficiency (PCE) of 24%.