Scientists Charge Batteries Using WiFi
Electronic devices like phones and cameras could be powered and charged using WiFi in the near future after successful research by scientists at the University of Washington.
The team successfully charged two types of batteries and powered a battery-free camera and temperature sensor using a system known as “power over WiFi” (Po-WiFi).
Po-WiFi uses a WiFi router to provide a field of wireless power without affecting its capabilities and without any modifications needed to existing routers.
Harvester sensors then pick up the radio frequency power and convert it into DC power in electronic devices.
The team were able to charge lithium-ion and nickel-metal hydride batteries at distances of up to 28 feet, and power a battery-free camera and temperature sensor at distances of 17 and 20 feet respectively.
They also carried out successful tests in six urban homes to demonstrate that the system works in the real world.
The scientists say PoWiFi could be used in the future to create charging hotspots where various devices can be charged from a centralized router, and could be used both at home and in offices as well as in public spaces.
WiFi routers generally do not send out a constant broadcast, but instead do it in short transmissions, which means they could not be used for Po-WiFi as-is.
But the University of Washington researchers installed a software update which can make routers deliver a steady signal so they can deliver enough power to the harvester.
They were able to provide enough power to the camera so that it had enough energy to take a picture every 35 minutes.
The team behind the research was made up of Vamsi Talla, Bryce Kellogg, Benjamin Ransford, Saman Naderiparizi, Shyamnath Gollakota and Joshua R. Smith.