BATLESS Microchip May Bring About IoT Devices That Don’t Require Batteries

A group of researchers from the National University of Singapore has designed a microchip capable of self-starting and continue to function even if there is no battery power. Known as BATLESS, the microchip features a tiny on-chip solar cell that measures-out to half of square-millimeter in size and can generate electricity even in low-light conditions. This is good news for small IoT devices that are deployed in remote locations where regular servicing of the device is difficult.

One of the critical issues of designing small IoT devices is battery size. Depending on the application and where those devices are deployed, they need a constant source of power, and therefore the battery needs to be incredibly efficient and long-lasting. With NUS’ new chip, battery size no longer matters as BATLESS can continue to operate even when the battery is drained. The researchers state that power can come from other forms besides the tiny solar cell, including vibration and heat energy.

The 16-bit microcontroller functions by switching between two modes — minimum-energy and minimum-power. As you might imagine, it runs in minimum-energy when battery power is present to maximize battery life and efficiency. When that battery is out of power, the chip switches over to minimum-power mode, which the researchers claim is “about a billion times smaller than the power consumption of a smartphone during a phone call,” or roughly a half of a nanoWatt.

Depending on the application, the chip can capture data, process it and time-stamp events of interest and transfer it wirelessly to the cloud when sufficient battery power becomes available to the device. The research team demonstrated their BATLESS microchip at the International Solid-State Circuits Conference (ISSCC) 2018 in San Francisco back in February of this year, which showed the chip could produce nanoWatts of power with just 50-lux indoor light intensity, the same amount of light during the twilight hours.

The researchers plan on developing new solutions to further their battery indifferent platform that covers the entire signal chain, from sensors to Wi-Fi and continue to endeavor to shrink battery technology with the long-term goal of removing the required batteries altogether.