Will we ever see battery-less phones? Maybe. Think of the biggest drawback to every mobile experience. Actually think of every portable device you ever owned and tell me what's the only thing that renders them useless after a period of time of usage.
The battery limits every single device. It renders them helpless as soon as is drained and your phone becomes useful only for throwing. But imagine if you didn't need a battery to send a message, upload a photo, or check your news feed. How could this be possible?
Every time you send a message your device directs a small amount of power to its radio to send a signal carrying your information, but researchers from the University of Washington have proposed the exact opposite: there might be no need for power to send small signals. They are calling the technology "ambient backscatter". It requires no battery and can wirelessly transmit simple messages.
This technology is different from RFID, the first battery-less technology proposed, in the fact that RFID requires the device to be close to a station that is close to a power source. With ambient backscatter there is no other pieces needed.
It works like a fish net. Since radio waves are all around us, ambient backscatter simply catches radio waves and converts them into small amounts of power. Now don't expect to FaceTime with this small amount of energy in your device. But it's enough to send a signal, store information, and light up a LED.
They also use less power when sending signals. They simply tweak existing air waves and re-write them in order for other devices to pick up the signal. The latest research done indicates that ambient backscatter works from almost 6.5 miles away from the nearest broadcasting station, maintaining a strong wireless signal. Although the distance might be not impressive for some, it should be noted that is not technology's limit, this is only the distance that they tested.
Because it's so early in the development the possibilities are incredible, but in the end they are still that, possibilities. Below is a video that further explains ambient backscatter. Will we ever see it in our phones? We hope so.