Rechargeable battery advice

[FsTop]

I've got an ARC_Mania Extreme III on the way, and I'm looking for advice on the trade-offs between AAA rechargeable battery types.

If the choices are Eneloops vs. unprotected Li-on cells, it looks as if they have comparable watt-hour capacity: 900mah @ 1.2v vs. 320mah @ 3.6v

My question is regarding run-time...

I know that the Li-on cells would be brighter, but I don't have any feel for how much brighter - maybe 50%? Maybe more?

If the light output were 50% greater on the Li-on cells, would the run-time drop by 1/3 due to the greater current consumption?

I'm looking for a general comparison of run-times between these two battery types in a AAA flash - any threads that explore the topic?

 

[VidPro]

using a unprotected li-ion in a light that will drain a 1.5v battery is not a choice its a disaster
only if you really watched what was happening , would it be a choice, as the unprotected li-ion would be drawn down to well below spec, this will ruin the battery and make it dangerous to charge.
ask people who have done this AFTER they have done 25+ runtimes of that , not when they first try it and go "WOW, that is bright", because it is all about the longevity issues vrses brightness of the moment.

If the light output were 50% greater on the Li-on cells, would the run-time drop by 1/3 due to the greater current consumption?

no the runtime would can drop to less than 50% , factoring in loads of stuff. like efficiency of the led at lower drive levels, and when heat can be removed. and factoring in if the led is then being overdriven even, which is fun and bright and all, but will reduce the time that the led last , with it dimming over time. most of what your asking here depends on how the driver itself acts with the hugely higher voltages, most of them act hugely different. it will also depend on the cell item your using, as they can act different, more different when driven hard.

now the li-ion of the AAA size , depending on the one, will not be ABLE to put out the full amperage anyways, so in some respects the drive of the flashlight will depend on how the voltage saggs from the li-ion. and that can vary GREATLY depending on the cell itself, even from the same manufacture.

so UN-protected li-ion for grand brightness, and short run, and short lived of all parts, normal voltages like ni-mhy and alkaline for , normal usage, and longevity of all items.

 

[mdocod]

the 320mAH rating on the AAA li-ion 10440 cell is probably a bit ambitious to say the least. 200mAH is more realistic for that size of Li-Ion cell. I don't think it's really worth it. A NIMH cell will deliver the power safely and probably survive a long healthy life in the light.

 

[FsTop]

Well, the light is rated to take up to 5.0v, and Li-on use is approved by ARC_Mania, so I'm not worried about frying the light instantly.

The Extreme also has selectable over-discharge protection - it cuts off at 3v, so the Li-on cells should last OK.

If it's really only 200mah output, that would certainly be an issue as to runtime, and I guess that if the efficiency drops off that badly, I don't see much point in having a solar flare that only lasts ten minutes.

So, bottom line is that I guess that I should be asking ARC_Mania, regarding the longevity of the light when using Li-on...

 

[EntropyQ3]

Well, the light is rated to take up to 5.0v, and Li-on use is approved by ARC_Mania, so I'm not worried about frying the light instantly.

The Extreme also has selectable over-discharge protection - it cuts off at 3v, so the Li-on cells should last OK.

If it's really only 200mah output, that would certainly be an issue as to runtime, and I guess that if the efficiency drops off that badly, I don't see much point in having a solar flare that only lasts ten minutes.

So, bottom line is that I guess that I should be asking ARC_Mania, regarding the longevity of the light when using Li-on...

The Extreme III is built around the LiteFLux LF2, which is as good as it gets as far as unprotected LiIon AAA safety goes. Not only is the light regulated at all outputs (check with ARC_Mania to what current) so the cell shouldn't get punished to hard by excessive discharge rates, the light also has a built in varning/protection against over discharge.

Neat and tidy.

That said, I'm not sure NiMH isn't preferable overall anyway. I run unprotected LiIon AAAs in my LumaPower Avenger, which also offers regulated output, but no protection against over discharge. I'd really prefer if it had that, and may go back to NiMH for that light as well. On the other hand I have had good experience with AW 10440 cells, I really do seem to get the advertised 320 mAh out of them.

You've got a great little light there, try it with both options and see what you prefer. At the cost of the Extreme III, you can afford it.

 

[VidPro]

Well, the light is rated to take up to 5.0v, and Li-on use is approved by ARC_Mania, so I'm not worried about frying the light instantly.

...

great, so i might recind the idea that it overdrives like almost everything else does
but the stats people are getting with other arcmania driver items , still show it will use more with more voltage.

so much info its confusing, but the basic premises are usually the same, no regulation is perfect, with huge voltage ranges and you might not want it to be either

http://candlepowerforums.com/vb/archive/index.php/t-89598.html
extreeme , super, ahh heck i dont know which one it is, so i shouldnt have said anything. just watch out for Claims of ability vrses actual regulation, the graphs usually tell it all.
so many time i have been told, even completly convinced, that things do what they say they will, and so many times the math and science and meter readings show that they do not.