Battery-free cell phones? Really!

SEATTLE – Cell-phone users are excited that the prototype for a battery-free cell phone might mean they could cut the cord to their chargers in the future. But the developing technology also may be a boon for the environment.

Developed at the University of Washington, the battery-free cell phone draws power from the air by “harvesting” radio frequency signals and turning them into energy. The prototype also uses “photodiodes,” which essentially are tiny solar panels.

Vamsi Talla worked as a research associate on the project. He says the technology would help cell phones last longer.

“Because t...