HZB hits 23.26% efficiency with CIGS-perovskite tandem cell
Scientists from the Helmholtz Zentrum Berlin research institute this morning presented a new world record efficiency for a tandem cell combining CIGS and perovskite technology at the EU PVSEC conference in Marseille. The development of an organic coating layer between the two semiconductors was key.
Helmholtz Zentrum Berlin (HZB) has set a new efficiency record of 23.26% with a perovskite/CIGS tandem cell measuring 1cm². That represents a significant improvement on the 21.6% achieved by HZB in February.
The new record means tandem cell efficiency is approaching the 23.35% record for a standalone 1cm² CIGS cell set in January by Solar Frontier. If scientists can demonstrate an efficiency gain for the tandem structure over a standalone cell, as has been achieved already with perovskite/silicon tech, the combination could garner significantly more interest.
Belgian research institute imec also achieved 24.6% efficiency with a perovskite/CIGS tandem device last September, with a cell measuring 0.5cm² and featuring a four-terminal structure, thus avoiding losses at the CIGS/perovskite interface.
The HZB record was presented this morning at the EU PVSEC conference in Marseille by scientist Steve Albrecht, who explained one of the key innovations that enabled the achievement was the development of an organic layer between the two cells, which reduced losses at the electrode separating the two active cell layers.