Researchers build flexible device able to convert Wi-Fi signals to electricity

Although wireless charging is becoming common, the device usually needs to be on top of a charging pad. For a true wireless charging experience, engineers have developed a new device that converts Wi-Fi signals to electricity.

Researchers from MIT and Technical University of Madrid invented a flexible, ultra-thin device that harvests energy from Wi-Fi signals and converts them into electricity that can power devices, wire- and battery-free.

The device, known as ‘rectenna’ – combination of rectifying antenna – is a type of antenna that converts electromagnetic energy into direct current (DC). The device uses a radio-frequency antenna to capture electromagnetic waves, like those produced by Wi-Fi, as alternating current (AC) waveforms.

These waveforms are then sent to 2D semiconductor that converts them into DC, producing about 40 microwatts from about 150 microwatts of Wi-Fi power. This much energy is enough to power small wearables, or medical electronic devices, eliminating the need for batteries, reported New Atlas.

Regular Wi-Fi can now be used to detect weapons, bombs

Due to the device being flexible, the rectenna can be deployed over large areas akin to wallpaper, or used in small, portable devices like flexible smartphones. The device could even be used in medical implants and swallow-able sensors, wrote Science Alert.

“Ideally you don’t want to use batteries to power these systems, because if they leak lithium, the patient could die. It is much better to harvest energy from the environment to power up these small labs inside the body and communicate data to external computers,” said engineer Jesús Grajal.

Moreover, the rectenna also relatively costs lower at larger scales and hence can be used for much bigger applications, as per the research publiched in Nature. “We have come up with a new way to power the electronics systems of the future - by harvesting Wi-Fi energy in a way that’s easily integrated in large areas - to bring intelligence to every object around us,” said engineer Tomás Palacios.