Future Wireless Devices Won't Need Batteries

Science is like dark magic – one day you wake up to news that phones can actually power themselves with invisible waves, all without any batteries. It’s like making energy out of thin air – something I try to do every morning but I’m not as good as these engineers from the University of Washington, whose use of ambient backscatter to wirelessly communicate will one day eliminate the need for batteries. Here’s how that battery-free concept might work: