Researchers develop technology to charge phones with sound

Cell phone users face problems at times, when they need to charge their handsets, as during travelling. In such situations, when the handset goes dead, cell phone users are left with no choice but to reach for the nearest power point.

However, that might soon become a thing of the past, with researchers now developing sound powered chargers. Thanks to the development, traffic noise, music and other sounds could soon be used to charge cell phones, phys.org reports. And of course, one's own voice could be put to the same use.

The development was confirmed by scientists from Queen Mary University of London and Nokia. Reports said, scientists had created an energy-harvesting prototype (a nanogenerator) to charge cell phones with everyday background noise.

According to Dr Joe Briscoe from QMUL's School of Engineering and Materials Science, being able to keep mobile devices working for longer, or do away with batteries completely by tapping into the stray energy that was all around us was an exciting concept.

The researchers used the key property of zinc oxide, a material which when compressed or stretched creates a voltage by converting energy from the mechanical stress resulting from the action, into electrical energy.

It is possible to create a sheet of zinc oxide nanorods and coat it on various surfaces in different locations, which makes the energy harvesting quite versatile. The nanorods bend when sound waves hit the surface, generating a voltage in the process.

A device based on the technology can generate five volts, which is good enough to charge a phone.