Nimh or alkaline for Dorcy AAA with MJLED mod

Hi, just modded my Dorcy AAA with a cut mjled and was wondering which is best to drive it for good brightness and runtime, a nimh or alkaline battery. Wasn't sure if 1.2 volts would be enough but if it is then I would think the nimh would have a flatter curve. Did search and couldn't find any runtime plots for this mod. Thanks! Also, would a lithium AAA be too much for current for the mjled? My mjled in minimag recently stobed and died using lithiums so I put in an extra mjled I had and am now using alkalines. Read that the lithiums in minimag are just too much for it.

Another newbie question. My keymate is modded with mjled using 4 SR44's. I think that is providing 6 volts. Why doesn't that destroy the stock led or mjled. Is it that the led's can take the higher voltage and it is higher currents that they are vulnerable to? Thanks

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farscape105 said:
Another newbie question. My keymate is modded with mjled using 4 SR44's. I think that is providing 6 volts. Why doesn't that destroy the stock led or mjled. Is it that the led's can take the higher voltage and it is higher currents that they are vulnerable to? Thanks

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Those small batteries have a high internal resistance. When they supply a current to a load, their voltage drops.

Paul

I don't know a lot about mjleds but I use nimh with an unmodded dorcy AAA and although it starts out not quite as screaming blue bright it stays brighter longer than alkalines do. As far as driving LEDs off coin cells, the smaller batteries have higher internal resistance which is essentially like adding a resistor in the circuit throttling back on voltage/current. There are a lot of 6v coin cell led lights out there, most use 3 LR44 or 2 lithium cells.

A battery with lower internal resistance will be able to provide current needed under increasingly heavy loads. I have a 3led 1AAA light that seems to work better on nimh than alkaline probably due to the same reason.

if anybody has pictures or descriptions here of your dorcy AAA mods , i would certannly be interested.
i got some to modify, because it looked like a workable platform in a psudo chrome look.

To find some cool Dorcy AAA mods seach for posts by Robocop . He's done several original jobs.

thanks