25 July 2018

Imec’s perovskite-silicon tandem cell efficiency of 27.1% beats standalone silicon solar cell

© Semiconductor Today Magazine / Juno PublishiPicture: Disco’s DAL7440 KABRA laser saw.

As a partner in Solliance and EnergyVille, nanoelectronics research centre imec of Leuven, Belgium has reported what it claims is record solar energy power conversion efficiency of 27.1% for its four-terminal perovskite/silicon tandem photovoltaic cell, beating the most efficient standalone silicon solar cell. Further engineering of the perovskite material can raise efficiency over 30%, it is reckoned.

Perovskite microcrystals represent a promising material system for making high-performance thin-film solar cells. They can be processed into thin, light, semi-transparent modules that can achieve high power conversion efficiency, are inexpensive to produce, and have high absorption efficiency for sunlight. Because they can be made semi-transparent, perovskite solar cells and modules can also be used on top of silicon solar cells. When the perovskite is carefully engineered, the absorbance in the perovskite minimizes the thermal losses that occur in the silicon cell. As a result, a perovskite-silicon tandem solar cell can potentially reach power conversion efficiencies above 30%.

Imec’s new record tandem cell uses a 0.13cm2 spin-coated perovskite cell - developed within its Solliance cooperation - stacked on top of a 4cm2 industrial interdigitated back-contact (IBC) silicon cell in a four-terminal configuration, which is known to have a higher annual energy yield compared with a two-terminal configuration. Additionally, by scaling up the tandem device by using a 4cm2 perovskite module on a 4cm2 IBC silicon cell, a tandem efficiency of 25.3% was achieved, surpassing the stand-alone efficiency of the silicon cell.

“We have been working on this tandem technology for two years now, and the biggest difference with previous versions is in the engineering and processing of the perovskite absorber, tuning its bandgap to optimize the efficiency for tandem configuration with silicon,” says Manoj Jaysankar, doctoral researcher at imec/EnergyVille.

“Adding perovskite on top of industrial silicon PV may prove to be the most cost-effective approach to further improve the efficiency of photovoltaics,” concludes Tom Aernouts, group leader for thin-film photovoltaics at imec/EnergyVille. “Therefore, we invite all companies in the PV value chain that are looking into higher efficiencies to partner with us and explore this promising path.”

See related items:

Imec boosts efficiency of 4cm2 perovskite/Si solar module to record 23.9%

Imec and Solliance boost efficiency for 4cm x 4cm perovskite PV module to 12.4%

Imec and Solliance partners report first semi-transparent perovskite modules

Solliance sets record 10% aperture-area conversion efficiency for scaled-up perovskite-based PV modules

Imec reports record perovskite thin-film PV module efficiency of 11.3%

Imec reports perovskite PV module with 8% efficiency

Tags: IMECSolliance Thin-film PV

Visit: www.imec.be

Visit: www.solliance.eu

Visit: www.energyville.be