Researchers use new process to fabricate perovskite solar cells with fill factors of over 86%

Researchers from the Australian National University (ANU), China's Sun Yat-sen University and Chinese Academy of Sciences (CAS) have reportedly set a new record conversion efficiency for perovskite-based solar cells, improving on a record they already held.

The recent research details how a solar conversion efficiency of 22.6% for a one square centimeter cell was achieved through improvements on previous perovskite solar cells.

ANU researcher and report co-author professor Kylie Catchpole said the latest achievement represents an important step towards commercially available perovskite solar cells. 'We're always trying to reach the highest efficiency we can. Commercialization won't happen without high efficiency,' Catchpole said. 'But we need a cheap process as well. This is an approach that definitely combines those two elements in a way that's different to how it's been achieved previously.'

The ANU research team said that the new solar cell design delivered a boost to efficiency and made the cells easier to manufacture.

Key to the efficiency boost was the discovery by the research team of a previously undetected flaw in earlier perovskite solar cell designs that has now been rectified for the first time.

'We've also been able to overcome an energy loss in one of the layers that scientists didn't previously realize was there,' professor Catchpole added. 'The modelling we've done shows this was a limitation in previous types of solar cells.'

ANU researchers set a solar conversion record for perovskite solar cells in 2019, achieving an efficiency at the time of 21.6%.

Last year, a separate research team also set a performance record for two-sided solar cells, which allow electricity to be produced from light hitting both sides of a solar cells.

The ANU had also initially set a world record efficiency for the tandem solar cells, using silicon and perovskite cells stacked together, achieving an efficiency of 27.7%. The Australian research team were eventually overtaken by a German-based research group, which has successfully achieved a 29.8% conversion efficiency.