Researchers create a 'battery-free' mobile phone

Researchers at the University of Washington have created a cellphone that requires no batteries.

The prototype requires just a few microwatts of power. It uses ambient power from radio signals and light to transmit a signal back to a base station 50 feet away.

Using just capacitive button, a circuit board and other "off the shelf" components, the team of researchers were able to prove that prototype can transmit speech and data and receive user input via buttons. They were also able to receive Skype incoming calls, dial out and place callers place callers on hold with the battery-free phone.
The new technology is published in a paper "the Proceedings of the Association for Computing Machinery on Interactive, Mobile, Wearable, and Ubiquitous Technologies."




“We’ve built what we believe is the first functioning cellphone that consumes almost zero power,” said co-author Shyam Gollakota, an associate professor in the Paul G. Allen School of Computer Science & Engineering at the UW. “To achieve the really, really low power consumption that you need to run a phone by harvesting energy from the environment, we had to fundamentally rethink how these devices are designed.”