Last week, researchers at the University of Washington announced successful tests of a battery-free cell phone.The phone harvests radio wave energy from a wireless base station (such as Wi-Fi) and converts light through miniature photo-diodes. It used very low power to transmit back to the base station. As a result, the phone does not have a battery, and thus never needs to be charged.
The researchers demonstrated voice call and even skype calls using this battery-free phone.
The prototype is made completely of commercial components.
At this time, the phone must be up to 30 feet away from this special base station, and is limited only to voice communications.
