Believe It or Not—a Battery-Free Cell Phone信不信由你：無電池手機時代來臨！
Do you sometimes worry that your phone will run out of power right when you need it most? Wouldn't it be great if you never had to worry about charging your phone ever again?
It might sound impossible, but a team from the University of Washington has built a cell phone that doesn't need a battery. The phone is powered by radio waves that are sent from a base station, which can be up to 31 feet away. Additionally, power can be provided by light.
The phone is very simple. It has no screen or casing. It can't take pictures or send text messages, but it has a number pad and can handle voice calls. It works similarly to a walkie-talkie, as only one person can speak at a time.
The phone's designers hope that the base stations used to provide power will one day be a common wireless technology like Wi-Fi. Don't throw away your charger just yet, but a battery-free future for phones is now possible—and that's something to get energized about.