Flexibility

Researchers from CHOSE (Centre for Hybrid and Organic Solar Energy) at Tor Vergata University of Rome, ENEA Frascati Research Centre, Fraunhofer FEP, University of Guilan and Halocell Europe have developed perovskite solar cells (PSCs) on polycarbonate films.

Despite polycarbonate's widespread use in many applications, poor chemical resistance and roughness have hindered its adoption as a substrate in solar cell technologies. These challenges were solved by developing a new planarizing layer over the polycarbonate films applied in liquid form using blade coating. This innovation reduced surface roughness from 1.46 µm to 23 nm, cut the water vapor transmission rate in half, and improved solvent resistance. As a result, the scientists achieved a power conversion efficiency of 13.0% for solar cells on polycarbonate substrates, with good durability and flexibility.

Australian start-up Halocell will reportedly begin producing flexible 7 centimeter-long photovoltaic strips that are said to generate enough power to replace the pair of disposable batteries in a TV remote, or the charger cable for a set of headphones. This represents the first large-scale manufacturing in Australia of perovskite PV technology.

The 5-volt Halocell perovskite strip. Image credit: Halocell

The Halocell modules will each cost less than a dollar to make and the Company has ambitious plans to produce millions per year, its CEO Paul Moonie said.

Flexell Space, an in-house venture of Hanwha Systems, has announced that it has signed a letter of intent (LOI) with Airbus Defence and Space GmbH (Airbus) to develop next-generation space solar cell modules using perovskite/CIGS tandem solar cell technology. This collaboration aims to revolutionize the efficiency and weight of space solar cells, marking a significant milestone in the aerospace industry.

Through this agreement, Flexell Space and Airbus plan to design and develop space solar cell modules that are more than half the weight of existing models while maintaining performance and efficiency. By applying Flexell Space's tandem solar cell technology, the new solar cells will aim to offer low cost, high efficiency, rapid production, and flexibility.

A collaborative project by leading Helmholtz Centers for photovoltaic research aims to accelerate the deployment of multi-benefit photovoltaics based on emerging printed PV-Technologies like organic photovoltaics and perovskites. 

Core Lab Perovskite PV at KIT. Image from Solar TAP website

The Solar Technology Acceleration Platform (Solar TAP) for emerging Photovoltaics brings together 3 Helmholtz Centers, 9 major research infrastructures, and more than 25 scientists. The three Helmholtz centers are: Forschungszentrum Jülich, Helmholtz Zentrum Berlin and Karlsruhe Institute of Technology. They are aligning their world-class infrastructures in order to create the joint Technology Acceleration Platform and providing fast and simple access to laboratories, equipment and scientists through collaborative pre-financed projects.

Rayleigh solar Tech has announced two significant lifetime stability results. First, a 15cm x 15cm glass solar module exhibited zero degradation after seven months of outdoor testing. Second, a 15cm x 15cm flexible solar module achieved T80 after 1200 hours of damp heat testing.

“Stability is the crux of any perovskite company’s business model” said Rayleigh CTO and Founder, Dr. Sam March. “This is a huge step towards the commercial viability of our perovskite PV. Rayleigh’s all-ambient slot-die coated carbon-based perovskite solar modules are efficient, low-cost, and are stable in the field”, he said.

Researchers from Australia's Monash University and CSIRO Manufacturing have reported a lamination technique, known as cold isostatic pressing (CIP), to build a perovskite solar cell based on a flexible bilayer electrode made of carbon and silver. The resulting electrode can reportedly compete with gold-carbon electrode based counterparts in terms of efficiency and stability.

The back side of a C-PSC with a custom-designed electrode after CIP processing. Image credit: Communications Materials

The researchers, led by CSIRO Manufacturing, which is part of Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO), explained that while perovskite solar cells (PSCs) with evaporated gold (Au) electrodes have shown promising efficiencies, the maturity of the technology still demands low-cost and scalable alternatives to progress towards commercialization. Carbon electrode-based PSCs (C-PSCs) represent a promising alternative, however, optimizing the interface between the hole transport layer (HTL) and the carbon electrode without damaging the underlying functional layers is a persistent challenge, which the team set out to address.

Researchers from Austria's Johannes Kepler University Linz have developed lightweight, thin (<2.5 μm), flexible and transparent-conductive-oxide-free quasi 2D perovskite solar cells by incorporating alpha-methylbenzyl ammonium iodide into the photoactive perovskite layer. 

The team fabricated the devices directly on an ultrathin polymer foil coated with an alumina barrier layer to ensure environmental and mechanical stability without compromising weight and flexibility.

High power conversion efficiency (PCE) flexible perovskite solar cells (FPSCs) are highly desired power sources for applications like aerospace and flexible electronics. However, their PCEs still lag far behind their rigid counterparts. To address this issue, researchers from Tsinghua University and National Center for Nanoscience and Technology developed a new fabrication technique that increases the efficiency of FPSCs, paving the way for use of the technology on a much larger scale. The scientists reported a high PCE flexible perovskite solar cell by controllable growth of a SnO₂ electron transport layer through constant pH chemical bath deposition (CBD). 

The team developed a new chemical bath deposition (CBD) method of depositing tin oxide (SnO₂) on a flexible substrate without requiring a strong acid, which many flexible substrates are sensitive to. The new technique allowed the researchers more control over tin oxide growth on the flexible substrate. Tin oxide serves as an electron transport layer in the FPSC, which is critical for power conversion efficiency.

Researchers from Hanyang University, Nankai University and Kookmin University have developed a room-temperature-processed tin oxide (SnO₂) ETL preparation method for flexible perovskite quantum dots (PQD) solar cells. Low-temperature ETL deposition methods are especially desirable for fabricating flexible solar cells on polymer substrates.

The process involves synthesizing highly crystalline SnO₂ nanocrystals stabilized with organic ligands, spin-coating their dispersion, followed by UV irradiation. The energy level of SnO₂ is controlled by doping gallium ions to reduce the energy level mismatch with the PQD. 

Eight mini-modules of the Commonwealth Scientific and Industrial Research Organization's (CSIRO) printed flexible solar cells were attached to the surface of Australia-based space transportation provider Space Machine Company’s Optimus-1 satellite, that was sent into orbit from the United States as part of Elon Musk’s Space X’s Transporter-10 mission.

A statement from the national science agency following the launch from Vandenberg Space Force Base in California explained that it is exploring such solar cells as a reliable energy source for future missions. Eight mini-modules of the printed flexible solar cells were attached to the surface of Optimus-1.