You may have used different battery-powered wearable devices, like a smartwatch, wearable camera, fitness trackers, etc. But, researchers at the University of Colorado Boulder have created an innovative, low-cost wearable device that’s powered by the human body.
The device, described today in the journal Science Advances, is stretchable enough to be worn like a ring, a bracelet, or any other accessory that touches your skin. Intended to turn the human body into a biological battery, this device contains thermoelectric generators that make use of the body’s internal temperature to generate electricity.
This ring-shaped device is self-healing and can power wearable gadgets like fitness trackers, and IoT devices.
How the wearable generator produces electricity from human skin?
The team of the University of Colorado researchers embedded thermoelectric generators — that works on thermoelectric principle — into a thin film that is made from polyimine, a stretchable polymer, and wired them together with a liquid gallium-indium alloy to create flexible bands. Such bands can be worn on arms, legs, and fingers. The device costs less than $10.
Futuristic wearable device
The team at the University of Colorado Boulder is hoping to power wearable electronics without the need for an external battery. According to the researchers, their devices can generate approximately one volt of energy for every square cm of the skin. The generated energy is less voltage per area compare to what many existing batteries offer. But it’s enough to power your wearable electronics, like fitness trackers or watches.
Jianliang Xiao, senior author of the new paper and an associate professor in the Paul M. Rady Department of Mechanical Engineering at CU Boulder, said, “Whenever you use a battery, you’re depleting that battery and will, eventually, need to replace it. The nice thing about our thermoelectric device is that you can wear it, and it provides you with constant power.”
Xiao and his team earlier experimented with designing a wearable device that appears and behaves just like natural human skin. However, the android epidermis needs to be connected to an external power source for its functioning.
‘Electronic skin’ is a recyclable substitute for wearable devices
But now the group’s newest innovation stats with a base that’s made from a stretchy polyimine. After that, scientists attach a series of thin thermoelectric chips within this material and connect all of them using liquid metal wires.
According to Xiao, the design makes this entire system stretchable without adding stain to the thermoelectric material that can be brittle. When these thermoelectric generators are in close contact with the human body, they use the body’s natural heat to dissipate into the environment.
He also mentioned that this power can also be increased by adding more generator blocks into the device. Xiao has compared this new design to a bunch of small Lego pieces whereby small units are attached to make a large structure, enabling flexible customization.
Just like electronic skin, this new wearable device is as resilient as biological tissue. In case, this device tears or breaks, the broken pieces can be pinched together and sealed again within a few minutes. The broken parts can also be immersed into a special solution that dissolves the polyimine base and separates the electronic components, allowing the components to be reused.
However, there are still many improvements that need to be made for the success of this device. Xiao believes that it could take up to five to ten years to bring these new wearable devices into the market.