Researchers at the University of Colorado Boulder have developed a new, low-cost wearable device that transforms the human body into a biological battery.
The device, described in the journal Science Advances, is stretchy enough that you can wear it like a ring, a bracelet or any other accessory that touches your skin. It also taps into a person’s natural heat–employing thermoelectric generators to convert the body’s internal temperature into electricity.
The concept may sound like something out of The Matrix film series, in which a race of robots have enslaved humans to harvest their precious organic energy. These devices can generate about 1 volt of energy for every square centimeter of skin space–less voltage per area than what most existing batteries provide but still enough to power electronics like watches or fitness trackers.
Scientists have previously experimented with similar thermoelectric wearable devices, but this device is stretchy, can heal itself when damaged and is fully recyclable–making it a cleaner alternative to traditional electronics.
This research team previously experimented with designing “electronic skin,” wearable devices that look, and behave, much like real human skin. That android epidermis, however, has to be connected to an external power source to work.
The group’s latest innovation begins with a base made out of a stretchy material called polyimine. The scientists then stick a series of thin thermoelectric chips into that base, connecting them all with liquid metal wires. The final product looks like a cross between a plastic bracelet and a miniature computer motherboard or maybe a techy diamond ring.
This design makes the whole system stretchable without introducing much strain to the thermoelectric material, which can be really brittle.
Just pretend that you’re out for a jog. As you exercise, your body heats up, and that heat will radiate out to the cool air around you. This device captures that flow of energy rather than letting it go to waste.
The thermoelectric generators are in close contact with the human body, and they can use the heat that would normally be dissipated into the environment.
We can easily boost that power by adding in more blocks of generators, similar to lego bricks.
The researchers calculated that a person taking a brisk walk could use a device the size of a typical sports wristband to generate about 5 volts of electricity–which is more than what many watch batteries can muster.
These devices are as resilient as biological tissue. If your device tears, for example, you can pinch together the broken ends, and they’ll seal back up in just a few minutes. And when you’re done with the device, you can dunk it into a special solution that will separate out the electronic components and dissolve the polyimine base–each and every one of those ingredients can then be reused.
News source: University of Colorado Boulder
