A solar cell thinner than spider silk has been unveiled today by a team of Austrian and Japanese researchers. The ultra-thin solar cell has a thickness of 1.9 micrometers and can be bent around a single human hair.
The solar cells considered so far to be the thinnest are about ten times thicker than the new cell.
“The total thickness of this device is less than a typical thread of spider silk,” the researchers said in a report carried by online science journal Nature Communications.
“Being ultra-thin means you don’t feel its weight and it is elastic,” said one of the researchers, Tsuyoshi Sekitani from the University of Tokyo.
The new ultra-thin solar cell was built on a PET substrate and has one of its electrode made from Calcium/Silver with a thickness of only 115 nanometers.
The active layer is actually something that has been invented a while ago – an organic solar cell called P3HT:PCBM, which in 2009 had been considered the most efficient of its kind (5 percent)
The other electrode is PEDOT:PSS, a polymer that’s both transparent and conductive .
“You could attach the device to your clothes like a badge to collect electricity (from the sun)… Elderly people who might want to wear sensors to monitor their health would not need to carry around batteries,” Sekitani told AFP, quoted by physorg.com.
Official efficiency figures haven’t been yet disclosed, but Sekitani said they’re currently working on making the cells convert more light into electricity.
The device is also less prone to mechanical damage even if they make it bigger. Its ultra-low thickness allows it to bend extremely and avoid being torn.
Well, this is just cutting edge news right now, but in five years, as the researchers estimate, we’ll also have practical uses to this cell and it may also be made available commercially.
The above image represents as follows: (a) Scheme of the ultra-light and flexible organic solar cell. The layer thicknesses are drawn to scale. (b) Extreme bending flexibility demonstrated by wrapping a solar cell around a 35-μm-radius human hair. Scale bar (also in c,d) 2 mm. (c) Stretchable solar cells made by attaching the ultrathin solar cell to a pre-stretched elastomer. They are shown flat (left) and at 30% (middle) and 50% (right) quasi-linear compression. (d) The device attached to the elastomeric support, under three-dimensional deformation by pressure from a 1.5 mm-diameter plastic tube. (e) SEM image of the PET surface of the solar cell in compressed state. The radius of curvature for the shown wrinkles is estimated to be on the order of 10 μm. Scale bar 500 μm. Image (c) Nature Communications 3, Article number: 770 doi:10.1038/ncomms1772
The research team: Martin Kaltenbrunner, Siegfried Bauer and other researchers from Johannes Kepler University of Austria as well as Sekitani and other contributors from University of Tokyo.