Researchers at the CEA's National Solar Energy Institute (INES) in France have raised their internal efficiency record for flexible perovskite solar cells to 21.2%, up from a previous 19.2%, on cells built on a PET substrate.
The improvement came from incorporating an anti-reflective coating and redesigning the cells' electrical connections to reduce energy losses. The result was achieved on an active area of 0.28 cm² - nearly three times larger than the 0.092 cm² device that currently holds the world record for flexible perovskite cells, at 24.52%. The team says the result shows that flexible perovskite cells can be scaled up in area while retaining a large share of their efficiency.
Flexible perovskite cells are of interest for applications such as smart textiles, space systems, and building integration, alongside compatibility with large-scale manufacturing. Achieving high efficiency on flexible substrates is more difficult than on rigid glass, since the polymer substrates require lower processing temperatures that can introduce defects into the perovskite structure.
The work was carried out as part of JUMP INTO SPACE, a four-year Horizon Europe EIC Pathfinder Challenge project (October 2024–September 2028) coordinated by the University of Rome Tor Vergata, with a consortium of seven partners across five countries, including CEA, ONERA, Helmholtz-Zentrum Berlin, the Universities of Turin and Siena, UNINOVA, and Polish perovskite manufacturer Saule Technologies. The project's overall goal is an all-perovskite tandem solar cell on a radiation-hardened, flexible photonic substrate, targeting 30% efficiency under AM0 (space) illumination for applications including small satellites, active debris removal, and lunar or Martian bases. The flexible single-junction cell reported here is a building block toward that tandem architecture.
The researchers said future work will focus on optimizing the cells' individual layers - including testing and adapting conductive materials to improve current extraction and environmental durability - as well as adapting the fabrication process to new flexible substrates better suited to heat, mechanical stress, and radiation exposure.
