How is this type of flashlight powered?

Question

At wal-mart they have flashlights with a little lever you pull out then crank around and it charges the flashlight. I'm going to get one next time I'm out there and open it up to see what I find, but I thought I'd ask anyway...how does the crank charge the battery?

Answer 1

Its just a miniature generator that charges a capacitor (battery). No big deal.

Handy lights, though. Good to throw in your glovebox or trunk or whatever. No worries if you forget about it for a couple years, it will still work. (And it won't be full of acid oozing, dead batteries)

Answer 2

The crank spins a magnet inside of a coil of wire - the kind of flashlight that you shake moves a magnet up and down through a coil - both types produce a current in the coil caused by the moving magnetic field. Some types charge a small button battery and others charge a capacitor.
Both types utilize LEDs because the current produced isn't very significant and LEDs use much less power than incandescent bulbs. The types with an actual battery require much less frequent charging vs. a capacitor type.
It's really pretty cool technology - you can also purchase a crank powered portable radio. I'm sure the battery manufacturers are really excited about these devises!

Answer 3

This is a simply manual generator hooked to a storage capacitor. when you crank the handle it turns a small generator which charges a large capacitor which in turn powers the LED bulbs for about 60 seconds or so.

Answer 4

Military Grade Tactical Flashlight : http://FlashLight.uzaev.com/?HZZh

Answer 5

He's right, basically when you turn the handle your spinning a magenet in a ring of wires. this creates the electricity needed, it's then stored in a capacitor until you push the button.
They're great flashlights to have. I have 1 in my car for emergencies.

Answer 6

You know how hydro electricity works, the water turns big turbines that convert the mechanical energy into electric energy. The same is true for this system.