Soldiers sometimes lug more than 30 pounds of batteries to run GPS units and other critical gear, so San Francisco company Ardica set out to give them a lighter power pack. Now a civilian version lets the rest of us charge our phones—and stay warm. Ardica’s Moshi Power System is the first to charge your heated winter clothes, like this jacket from Mountain Hardwear, and your gadgets.
Ardica’s military pack, now in testing, tucks hydrogen fuel cells and lithium-ion batteries into a flexible case. The Moshi uses only batteries, since fuel cells aren’t widely available. But the layout is similar: Seven 2.75-inch batteries are linked inside a foam sleeve, so the 11.3-ounce package can flex at the joints. It slips into the jacket’s back and holds enough power to simultaneously drive heat-creating conductive yarn and send current to a USB cord in a pocket. You get about nine hours of heat or 11 iPhone charges before you have to plug it in.
Sturdy plastic connectors hook the Moshi to a jacket’s wiring. Detach them, and it becomes a portable charger that you can transfer to several compatible coats or take on its own on your next mission.

138 years of Popular Science at your fingertips.
Each issue has been completely reimagined for your iPad. See our amazing new vision for magazines that goes far beyond the printed page
Stay up to date on the latest news of the future of science and technology from your iPhone or Android phone with full articles, images and offline viewing
Featuring every article from the magazine and website, plus links from around the Web. Also see our PopSci DIY feed
Science is reinventing play, from extreme sports to gamification to ridiculous roller coasters to the playgrounds of tomorrow, and this issue is chock full of fun. Also, on a less fun note: Did global warming destroy my hometown?