A future without phone chargers may be coming soon

Cell phones have advanced a lot in just a few years, but we’re still living in the age of portable battery packs and constantly searching for a free outlet at a coffee shop to recharge. Now, a group of computer scientists have a phone prototype that has no battery at all — instead, it gets its energy from ambient radio signals and light.

“We’ve built what we believe is the first functioning cellphone that consumes almost zero power,” Shyam Gollakota, an associate professor of computer science and engineering at the University of Washington, said in a release.

Here’s how it works

In order to create a phone that can run on ambient power, scientists had to eliminate some energy-sucking processes. Instead of designing phones that convert analog signals into digital data to make sound, scientists opted to rely on small vibrations in the device’s speaker and microphone.

“This process essentially encodes speech patterns in reflected radio signals in a way that uses almost no power,” the release said.

However, there are some issues that make it not quite ready for consumption. It doesn’t look exactly like a cell phone — there’s no screen and users have to push a button to toggle between speaking and listening modes. The phone also doesn’t communicate with ordinary cell phone towers, though scientists imagine a future where Wi-Fi and base towers all have this technology integrated into it.

“You could imagine in the future that all cell towers or Wi-Fi routers could come with our base station technology embedded in it,” Vamsi Talla, a former electrical engineering doctoral student and Allen School research associate at the University of Washington, said in the release. “And if every house has a Wi-Fi router in it, you could get battery-free cell phone coverage everywhere.”

But they’re not done yet — the next step is to add a display screen and encrypt the phones so that conversations are safe. And if these cell phones become market-ready, they could rid of us chargers once and for all.