Best batteries for the maximum brightness

[mailint]

Given the space of a tube (a laser pointer) for 2xAAA batteries, what are the best batteries to power a Cree XR-E or Luxeon Rebel or SSC P4 LED, wanting the maximum brightness for 10 minutes?

[ak645]

Energizer lithium L92.

Given the space of a tube (a laser pointer) for 2xAAA batteries, what are the best batteries to power a Cree XR-E or Luxeon Rebel or SSC P4 LED, wanting the maximum brightness for 10 minutes?

[Marduke]

Energizer lithium L92.

+1

[mailint]

+1

This is what I thought too but then I thought that under the load of the LEDs the voltage of 2xAAA would go around a total 2.5V that would be too low.

Look here what happens to a AA Energizer lithium battery under load:


I think that I would better fill my 2xAAA-format laser tube with another combination of batteries, with an higher total voltage.

Any suggestions?

[Marduke]

Detailed info here:
http://data.energizer.com/PDFs/l92.pdf

L91 is AA format

[ak645]

Let me see if I understand.You want to direct drive an LED at 1.4 amps on 2XAAA? In a tiny little pen light? Good Luck with that.

Andy

[onthebeam]

You will get extra pop from a Panasonic Oxyride. Brighter than the lithiums in my experience but without the smoother runtime curve.

[LEDcandle]

There are only so many batteries available commercially.... and if you decide to go with li-on 10440, be careful that the capacity is only 300mah... its probably safer to stick within 1.5C.

And what's up with starting so many threads practically talking about the same thing.....

[Marduke]

And what's up with starting so many threads practically talking about the same thing.....

Yeah, just noticed that too. mailint, you've asked the same question several times and gotten the same answer. You can't get 2A out of 2xAAA. Even 1A would be pushing it. The only way to get more power would be to use a capacitor setup, but that would release all the energy much, much faster (in seconds, or milliseconds). I would suggest lowering your standards in this instance.

[mailint]

There are only so many batteries available commercially.... and if you decide to go with li-on 10440, be careful that the capacity is only 300mah... its probably safer to stick within 1.5C.

I also noticed that apparently low "300mah". Isn't it that it's calculated at a different load?

[mdocod]

a li-ion has about 3x the voltage and about 1/2(or less) the AH capacity of a similar sized NIMH cell. Overall energy density is usually higher with li-ion but in cell formats that small, li-ion isn't exactly on the bleeding edge...

I think I would find the smallest 500+mA driverboard I could, run it on a pair of NIMH AAAs and call it a day.

[Marduke]

Just don't confuse lithium-ion with lithium primaries. They are different chemistries with different performance.