Battery independant light

Anyone ever think of doing this:

A flashlight that can take one of ANY AAA, AA, C, D cell battery without any extra carriers or other stuff.

It would use multiple concentric spring loaded rings that either slide up against the battery or are pushed down if the battery is too large (and they stop the cell from moving).
The battery can't slide around either as the rings are lined with foam.

The tail cap is just a flat piece of metal.

It would be really nifty I think.

An explanation:

A C cell is placed into the battery compartment, where it slides down and presses against the AAA, AA and C rings. Pushing them down into the front part of the light.
The D cell ring slides past it but the foam still contacts the outside of the cell.

There would be of course a wide tolerance voltage regulator (or even several regulators depending on voltage) to permit use of any 1.2V to 3.6V cell in a common size.
Since the light can run from a wide variety of cells it should have a few different lighting options as well, LEDs of several colours (white, red, green, amber), and several brightness modes.

This light could not be super small due to the battery compartment design, but still should only be fairly small. (like a 1D modded Mag)

Good idea or what? (assuming it can be built)

Hmm.. this reminded me of a certain Energizer flashlight that I have seen in stores. http://www.energizer.com/products/flashlights/flashlight.asp?cat=1

May need to put in a switch or something to change from one battery setup to another or such perhaps.

That Energizer demo got me pumped.

Milkyspit's Milky Candle can use a AAA, AA, 123, CR2 without changing battery packs. Works on a modifided spring like you suggested.

Flashfirstask?later said:

Hmm.. this reminded me of a certain Energizer flashlight that I have seen in stores. http://www.energizer.com/products/flashlights/flashlight.asp?cat=1

May need to put in a switch or something to change from one battery setup to another or such perhaps.

Click to expand...

That is interesting. Add the forthcoming SMJLED PR flange based bulb from Lambda and you got a nice adaptable light.

My idea has always been to have *just* the head with a switch and electronics in it.
It could use some minimum to some maximum depenant on the driver say 3 - 12.
The battery would be connected either by a cord or snap-on depending on the use.
This would be easy to do with a Mag (screw-on rather than snap-on) and you could have 3, 2, 1, 0 cell bodies. If you wanted 20 amp hours it could go into a belt around your waist using a cord and the 0 cell body.

The Energizer Quick Switch is neat... if only it used a lux.

Didn't DSpeck's UBH project did something similar? I didn't follow that one too closely.

Well the idea was to simply drop in any common cell, close the hatch.
Push the ON button and have it work.

Having to manually select a battery type to use is silly.

I'm surprised this has not been done more often.

Has anyone ever used that energizer quich change light?

I can't imagine it being anything but plastic craptastic. (but you never know)