Researchers from RenShine and Nanjing University claim to have achieved a new world record for all-perovskite tandem solar cell efficiency
They achieved 28.2% steady-state efficiency over an area of 1.05 cm², tested by an independent international certification agency
They worked on the inhomogeneity issues seen in these cells at a large scale, as well as on ETL to improve their performance
Perovskite solar PV cell producer RenShine Solar of China, along with researchers from Nanjing University, has reported achieving 28.2% stabilized power conversion efficiency of 28.2% for all-perovskite tandem solar cell, over an area of 1.05 cm².
This, it claims, as a new world record for this kind of solar cell, and exhibits the potential of this technology. It was tested by an international 3rd party authoritative certification agency, according to Renshine.
To achieve this efficiency level, the team made more ‘precise efforts’ in the research and development (R&D) of large-area all-perovskite tandem solar cells, and solve the problem of uneven film formation of the functional layer.
One of the major problems that the researchers identified relates to the inhomogeneity in wide-bandgap (WBG) perovskite solar cells (PSC) at a large scale. It originates with the formation of the top interface and within the perovskite bulk itself. Poor electron transport layer (ETL) also significantly limits the device performance.
To enhance the efficiency, the team introduced a mixture of 4-fluorophenethylamine (F-PEA) and 4-trifluoromethyl-phenylammonium (CF3-PA) to create a tailored 2-dimensional perovskite layer (TTDL). In this, F-PFA forms a 2-dimensional perovskite at the surface, reducing contact losses and inhomogeneity while CF3-PA enhances charge extraction and transport.
These measures led to a high open-circuit voltage of 1.35 V and an efficiency of 20.5% in 1.77-eV WBG PSCs at a square centimeter scale, according to the research work.
“By stacking with a narrow-bandgap perovskite sub-cell, we report 1.05 cm2 all-perovskite tandem cells delivering 28.5% (certified 28.2%) efficiency, the highest among all reported so far. Our work showcases the importance of treating the top perovskite/ETL contact for upscaling perovskite solar cells,” reads the research abstract.
Their research has been published in Nature journal under the title Homogenized contact in all-perovskite tandems using tailored 2D perovskite.
In 2023, RenShine reported a 29% steady-state efficiency for its cell, but on a small designated area of 0.04888 cm² (see 29.0% All-Perovskite Tandem Solar Cell Efficiency).
It also features in the China Renewable Energy Society PV Committee’s highest research level solar cell efficiencies as of June 2024 for achieving 30.1% da efficiency for perovskite-perovskite tandem cells (see CPVS Releases China’s Highest Research-Level Solar Cell Efficiencies).
RenShine recently deployed its commercial perovskite modules and grid-connected a 1.2 MW perovskite rooftop solar power station in China that exceeded 3,000 kWh/day power generation on day 1 (see China Solar PV News Snippets: DAS Solar’s TOPCon 4.0 Plus Performance & More).