The Sweat-Powered Smartwatch

Why you may never need to charge your wearables again

For hundreds of years, self-winding watches have offered the wearer a symbiotic relationship not attained with regular automatic or manual watches. Automatic watches rely on a battery and manual watches rely on the wearer to regularly wind them by hand. But there is an aspect of the organic and the intimate with self-winding watches. They capture the motion of the wearer throughout the day to automatically wind themselves, adding back tension to the mainspring. These watches have been around since the late 1700’s but the motion-capture mechanism was perfected only recently by the iconic watchmaker Rolex. They are charming, self-reliant pieces of art.

We rarely feel the same about our smartphones, wireless earbuds, or smartwatches. An Apple Watch will only last about a day on a full charge because of the myriad of features available to its users. There is always a trade off between the number of features and the life of our batteries so that most of us can’t imagine using electronic devices without also being tethered to an outlet or carrying around a hefty battery for energy storage.

This is one of the trickiest technical obstacles facing wearables today. The challenge is to create wearables that are sleek and functional without the need to continually…