Researchers at the Ningbo Institute of Materials Technology and Engineering (NIMTE) in China have achieved a significant breakthrough in solar technology by developing flexible tandem solar cells with a stabilized efficiency of 24.6 percent, marking one of the highest efficiencies recorded for flexible solar cells. This advancement utilizes a novel antisolvent-seeding approach to effectively bond the different layers of tandem solar cells, combining a copper indium gallium selenide (CIGS) layer with a perovskite top layer. Traditional solar cells have a maximum efficiency of around 22 percent, often losing as much as 80 percent of sunlight to waste. By stacking solar cells with different energy-absorbing capabilities, tandem cells can increase overall efficiency, thus promising greater energy harvest from solar power.
The innovative methods employed by the NIMTE research team involved using high and low-polarity solvents to create a well-adhered monolithic structure, which addressed past challenges of poor bonding between CIGS and perovskite layers. In testing, the newly developed solar cell maintained 90 percent of its initial efficiency after enduring over 300 hours and 3,000 bending cycles, demonstrating both stability and mechanical durability. This achievement signals potential for practical, commercially viable applications of flexible tandem solar cells in various environments, offering a promising avenue for expanding the capabilities of solar energy technologies. The study’s results were published in the journal Nature Energy, emphasizing the future prospects of higher energy conversion efficiencies in flexible solar applications.