This Design Idea describes a high-intensity, rechargeable flashlight system that you can build from a 6V lantern-type flashlight. The rechargeable battery comprises four 2V, 2.5-Ahr (ampere-hour) SLA ...

And if there's one item that every homeowner should have, it's a rechargeable flashlight. Long gone are the days where you ...

According to its creators, not only can the ZeroHour XD tactical flashlight blast 1,000 lumens of light into the evening darkness for up to six hours, it can charge an iPhone seven times (though it ...

Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. Don’t throw out that seemingly lifeless battery—it’s not dead ...