Sound-Charging Cellphone Could Let Your Power Your Phone By Talking

In the future, you could charge your cell phone just by chatting.

 Researchers at South Korea's Sungkyunkwan University have developed a new technology that converts sound waves into electrical energy, The Telegraph reports. With the sound-harvesting tech, batteries could be charged by everything from the human voice and music to the sound of highway traffic.

       Researcher Dr. Sang-Woo Kim said, "The sound that always exists in our everyday life and environments has been overlooked as a source. This motivated us to realize power generation by turning sound energy from speech, music or noise into electrical power."

      Currently, the researchers have created a prototype that converts sounds around 100 decibels (think: noisy traffic) to 50 millivolts of electricity. Here's how it works: a pad absorbs sound waves and causes zinc oxide wires mounted between electrodes to compress and release, creating an electrical current that can be used to charge a battery.

      Fifty millivolts isn't enough to charge a mobile phone, but Dr. Kim said that the technology could be improved by using different materials. Fortunately, the current prototypes create enough energy to be usable in small, low-power sensors and implantable devices.