Now new research promises a way to recharge phones using nothing but the power of voice alone. A new technique, developed by a researcher at a South Korean university could use the sound around the devices to trickle-charge batteries, and get a boost by using the surplus energy when a person speaks into their mobile phone.
Yet, there might be a downside to this innovated technology, it could give people a new excuse to shout into their phones as they try to squeeze in every bit of extra power they can.
Dr Sang-Woo Kim, who has been developing the design at the institute of nanotechnology at Sungkyunkwan University in Seoul, South Korea, stated that "The sound that always exists in our everyday life and environments has been overlooked as a source [of scavenged energy]. This motivated us to realise power generation by turning sound energy from speech, music or noise into electrical power." "Sound power can be used for various novel applications including cellular phones that can be charged during conversations and sound-insulating walls near highways that generate electricity from the sound of passing vehicles.
The technology uses tiny strands of zinc oxide sandwiched between two electrodes. A sound absorbing pad on top vibrates when sound waves hit it, causing the tiny zinc oxide wires to compress and release. This movement generates an electrical current that can then be used to charge a battery.
