- 10×10 cm2 perovskite single-junction module with an initial active area efficiency of 14% and 12% steady-state efficiency
- Demonstrated scalability of single-junction perovskite-based solar cell, using industrially compatible processes
- Full laser patterning allowing for minimal dead areas
- Both NIP and PIN single-junction perovskite modules with steady state efficiency above 12% relying on industrial sputtering processes such as sputtering (ALD as slot die coating)
In a first step, modules with planar SnO2 Electron Transporting Layer (ETL) were fabricated by varying the perovskite deposition and the layout. The planar architecture was based on SnO2 processed at low temperature by spin-coating.
The results showed the performance of planar SnO2-based modules, which guaranteed higher open circuit voltage (Voc) and fill factor (FF) values, compared to standard architecture based on mesoscopic TiO2 scaffold. The absorber layer for these modules was composed by a mixed cation perovskite using the following precursors: PbI2, PbBr2, FAI, MABr, CsI. A DMF/DMSO mixture was used as a solvent of the perovskite (PK) solution. In a successive stage, modules with non-optimised layout were fabricated and formed on 10 cells with 7mm width.
The results show an efficiency of 10.9% on as substrate area of 10×10 cm2. The main factors limiting the efficiency were both low FF and low short circuit current (Jsc) values, equal to 58.8% and 16.7mA/cm2. In order to improve these important parameters, two factors were optimised: the PK layer and the module layout. The light absorption of the PK layer was increased by varying the spin-coating program during the PK deposition. Furthermore, an optimised layout design was developed in order to reduce the impact of the ohmic losses due to the fluorine doped tin oxide (FTO) substrate. The new layout was formed by 15 series connected cells with a cell width of 4.5mm. An optimised condition for P1-P2-P3 laser ablations was used to pattern the modules. The results show an active area (47.2 cm2) efficiency of 15% for a module fabricated with planar architecture on a SnO2 ETL and substrate area of 10x10cm2. Lastly, a Maximum Power Point Tracking was used to assess the stabilised efficiency of the modules which results to be equal to 12% after 180s.
The improvement of photovoltaic (PV) parameters on substrate areas equal to 10×10 cm2 is an important requirement for the further development of perovskite photovoltaic technology and to achieve the final scaling-up needed for commercialisation. The demonstration of mini-modules produced with up-scalable processes and materials are equally important to demonstrate the potential of perovskite photovoltaics technology outside the laboratory and beyond the realm of academic research. This result is therefore not only targeting PV researchers.
The 10x10cm2 perovskite single-junction module results were achieved in collaboration between the CHEOPS partners Centre Suisse d’Electronique et de Microtechnique (Project Coordinator) CSEM and
Università degli Studi di Roma ‘Tor Vergata’.
The 10×10 cm2 result is described further in Deliverable 1.5 available for download under reports.
The proof-of-concept result help further development and up-scaling of the perovskite/silicon tandem technology. Read more about CHEOPS’ results in on perovskite/silicon tandem technology.