New record for flexible thin-film solar cells

Never before has such an efficient flexible CIGS solar cell been built. Empa researchers achieve an efficiency of 20.8% for the first time - breaking their own record. Empa

Flexible solar cell with unprecedented efficiency: The Empa Laboratory for Thin Films and Photovoltaics, headed by Ayodhya N. Tiwari, has broken its own record. The researchers improved the efficiency of energy conversion in CIGS solar cells on flexible polymer substrate to 20.8%.

This is 0.4% higher than the previous mark – which is held by the same group. The technology of choice is copper indium gallium diselenide (Cu(In,Ga)Se2) or CIGS, which enables the manufacture of flexible, lightweight solar cells on polymer films.

The technological achievements and scientific findings are described in the special issue “Excellence in Energy” of the journal “Advanced Energy Materials”.

Three measures for success

The new record is the result of a combination of three major improvements, explains Romain Carron, head of CIGS research at Empa's laboratory. “First, we have carefully adjusted the chemical composition of the absorber layer to improve its electronic and optical properties.

Then we developed new methods for alkali metal doping. And finally, we have adapted the properties of the absorber-buffer interface to improve cell performance.” In particular, Shiro Nishiwaki's meticulous work was essential to improve the performance of the cells, says Carron.

Flexible CIGS solar modules are already commercially available, in particular from the Empa spin-off Flisom, which was co-founded by Tiwari. “Such high efficiency as we have now achieved in our laboratory demonstrates the potential of the technology. Future developments will be aimed in particular at transferring our new process from laboratory to industrial scale in order to increase the power generation and profitability of photovoltaic systems,” says Tiwari.

Dr. Romain Carron
Thin Films and Photovoltaics
Phone +41 58 765 47 91
romain.carron@empa.ch

R Carron, S Nishiwaki, T Feurer, R Hertwig, E Avancini, J Löckinger, S‐C Yang, S Buecheler, A N Tiwari, Advanced Alkali Treatments for High‐Efficiency Cu(In,Ga)Se2 Solar Cells on Flexible Substrates, Advanced Energy Materials, DOI 10.1002/aenm.201900408

https://www.empa.ch/web/s604/cigs-record-2019

Media Contact

Karin Weinmann Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All latest news from the category: Power and Electrical Engineering

This topic covers issues related to energy generation, conversion, transportation and consumption and how the industry is addressing the challenge of energy efficiency in general.

innovations-report provides in-depth and informative reports and articles on subjects ranging from wind energy, fuel cell technology, solar energy, geothermal energy, petroleum, gas, nuclear engineering, alternative energy and energy efficiency to fusion, hydrogen and superconductor technologies.

Back to home

Comments (0)

Write a comment

Newest articles

A new puzzle piece for string theory research

Dr. Ksenia Fedosova from the Cluster of Excellence Mathematics Münster, along with an international research team, has proven a conjecture in string theory that physicists had proposed regarding certain equations….

Climate change can cause stress in herring larvae

The occurrence of multiple stressors undermines the acclimatisation strategies of juvenile herring: If larvae are exposed to several stress factors at the same time, their ability to respond to these…

Making high-yielding rice affordable and sustainable

Plant biologists show how two genes work together to trigger embryo formation in rice. Rice is a staple food crop for more than half the world’s population, but most farmers…