This tiny Bluetooth chip doesn’t need a battery because it harvests energy from the air

The Internet of Things promises to connect billions of otherwise ordinary devices to the internet, but when each one needs to have its own battery, there’s a limit to how small or cheap they can become. A new paper-thin Bluetooth chip that’s able to operate entirely without a battery could be about to solve this problem. The postage stamp-sized chip from Wiliot is able to harvest energy from the ambient radio frequencies around us, such as Wi-Fi, Bluetooth, and cellular signals, and use them to power a Bluetooth-equipped ARM processor that can be connected to a variety of sensors.

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