While I love the happy buzz I get after a good workout, sometimes I could do without the actual glow. So I was pretty excited to learn all my hard-earned sweat could soon be put to good use, thanks to a new biobattery that uses the lactate in sweat to keep electronics at full charge. Imagine never having to worry about your playlist cutting out or losing your Strava stats mid-run again, thanks to nothing more than the power of your very own perspiration.
Sounds pretty cool, but totally far fetched, right? That's what I thought too, which is why I reached out to Dr. Joseph Wang—a nanoengineer at the University of California San Diego, who presented his work at the latest meeting of the American Chemical Society—to find out how, exactly, a little sweat could do all that.
Basically, it's science at its coolest: Electrodes are printed on temporary tattoo paper and transferred to your skin just like those colorful, wet-and-stick tats that you loved as a kid. The lactate in your sweat is then turned into useable energy to power whatever electronic device is on top of the tattoo (so, for instance, you could put the tat on your wrist and keep your fitness tracker charged). "This is the first device to harvest energy from your body’s lactate in a noninvasive way," says Wang. "It allows us to power a wearable device without having to insert electrodes under the skin."
Right now, the tiny tattoo (it's only 1 square-inch) is strong enough to power small devices such as a watch, fitness tracker, and a wearable glucose monitor, but Wang and his team hope future models will be powerful enough to charge your smartphone. Another perk: The device also works as a fitness tracker. You can see how efficiently you’re working out based on the power output that reflects your lactate levels. (The more efficiently you work out, the less lactate you produce.)
So when will the average exerciser be able to get their hands on them? There's no release date yet, but the San Diego-based company Electrozyme is working hard to bring the technology to consumers. So while we're still stuck with regular ol' watch batteries for now, the future of exercise is looking pretty darn cool.
