Photo/IllutrationThis shirt contains an ultra-thin solar battery. (Provided by Riken)

  • Photo/Illustraion

Japanese researchers said they have developed solar cells that are so slim that they can be used in clothing and still function after being cleaned in a washing machine.

The team was led by Kenjiro Fukuda, a researcher at the Riken Center for Emergent Matter Science, and Takao Someya, an electrical engineering professor at the University of Tokyo.

The research on the batteries, which are 3 micrometers thin, was published on Sept. 18 on the website of Nature Energy, a British science journal.

The solar batteries were created by coating an organic compound with semiconductor properties onto a polymer membrane to create photovoltaics.

The photovoltaic was about twice as efficient in converting solar rays into electricity than ordinary ultra-thin solar batteries.

The stretchability and water resistance of the batteries were improved when the cell was sandwiched between two layers of transparent rubber film.

The function of the cell did not decrease even after it was washed with detergent.

Fukuda said the battery could be attached to clothing and used to power medical devices that constantly monitor the wearer’s blood pressure and body temperature to detect early signs of illness.

The battery could also be used for an ultra-thin smartphone that is sewn into clothing, Fukuda added.