Flexible tandem perovskite/CIGS solar cells with 23% conversion efficiency reported by Solliance and MiaSolé

Solliance and U.S-based MiaSolé announced a new record - power conversion efficiency of 23% on a flexible tandem solar cell: a top flexible semi-transparent perovskite solar cell with a bottom flexible copper indium gallium selenide (CIGS) cell.

Solliance and Miasole's 23%efficiency tandem perovskite/CIGS cells image

This achievement comes only 9 months after the January 2019 announcement by Solliance and MiaSolé regarding a flexible solar cell with an impressive power conversion efficiency of 21.5%. The solar cell, similarly to this newly announced one, combined two thin-film solar cell technologies into a 4 terminal tandem solar cell stack: a top flexible semi-transparent perovskite solar cell with a bottom flexible copper indium gallium selenide (CIGS) cell.

The CIGS bottom cell was developed by MiaSolé Hi-Tech, a provider of CIGS production turn-key factories and manufacturer of CIGS flexible solar panels, located in Santa Clara, California. The CIGS cell used in this tandem architecture is based on a commercially available high efficiency flexible solar cell technology fabricated on lightweight stainless-steel foil using a proprietary high throughput roll-to-cell sputtering process. Recently, MiaSolé reported a flexible large area certified module efficiency of 17.44% with an active area of 1.08 m2.

As a result of the combined expertise of MiaSolé Hi-Tech in CIGS development and manufacturing and the Solliance team in the area of perovskite technology, the new record efficiency flexible perovskite/CIGS tandem cell was produced. 'A highly efficient flexible hybrid solar cell is an outlook on how perovskite solar cell technology can innovate the established solar technology, leading to a different application area with improved performance' according to Sjoerd Veenstra, Program Manager for Perovskite-based Solar Cells at Solliance.

'This significant tandem cell performance gain was achieved through process improvements in the bottom CIGS cell', adds Director of Technology at MiaSolé Hi-Tech Dmitry Poplavskyy, 'These process changes, implemented by MiaSolé, enable high efficiency CIGS cells with the spectral response better matched to the top perovskite cell. Further improvements in spectral matching as well as overall higher CIGS cell efficiency are expected to push the tandem architecture well beyond 23%'.

Posted: Sep 12,2019 by Roni Peleg