This post is also available in: heעברית (Hebrew)

Solar cells as an energy source are integral for building electrical devices, but high-efficiency solar cells often lack flexibility, therefore their application in wearable devices has so far been very limited, until now.

In order to build stretchable solar cells that can function under strain, their photoactive layer (the layer that converts light into electricity) has to show high electrical performance while possessing mechanical elasticity. However, achieving both of these capabilities is challenging, which makes the development of practical stretchable solar cells difficult.

A research team from the Department of Chemical and Biomolecular Engineering (CBE) led by Professor Bumjoon Kim announced in December that they are developing a new conductive polymer material that achieves high electrical performance and high elasticity, essentially introducing the world’s highest-performing stretchable organic solar cell.

According to Techxplore, organic solar cells are devices whose photoactive layer is composed of organic materials. These cells are lighter and more flexible than the standard non-organic material-based solar cells, which makes them highly applicable to wearable electrical devices.

The team joined a highly stretchable polymer and an electrically conductive polymer with excellent electrical properties through chemical bonding and developed a new conductive polymer with both electrical conductivity and mechanical stretchability. This new polymer has the highest level of photovoltaic conversion efficiency ever reported while being 10 times more stretchable than existing devices.

The team managed to build the world’s highest-performing stretchable solar cell that can be stretched up to 40% during operation and demonstrated its applicability for wearable devices. Professor Kim, who led the research, said that beyond the development of the cells themselves, the major achievement is the development of a new polymer that can be applicable as a base material for various electronic devices that need to be malleable and/or elastic.