Working up a good sweat can be its own reward. But instead of letting all that bodily moisture go to waste, why not let it power your smartphone — via a smart tattoo?
Researchers at the University of California in San Diego, led by Joseph Wang, are wringing more out of sweat — specifically, enough electrical current to potentially power personal electronics while you’re still on the treadmill.
See also: 50 Tattoos That Prove Nerds Are Badass
They’ve developed a temporary tattoo sensor that responds to lactate — a byproduct of physical activity, found in sweat and in the bloodstream.
The sensor strips electrons from the lactate, enough to generate an electrical current. That enables doctors to measure lactate levels — but the team also built a bio-battery into the sensor, storing some of the electricity. Read more…