Fenix L2D: How Draining is It?

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If one uses AA alkalines rather than lithium, will the L2D have problems draining the batteries on "Low" mode? I know they're not very efficient in the higher modes, but lithium batteries don't seem to be as plentiful as alkies and I have a bundle of alkies. I keep waiting for someone to produce a good, cheap AA lithium, but so far no one has.

I've recommended the L2D to most of my friends because they just will never get around to buying 123As (rechargeable or lithium). I charge my AAs, but in the event of a hurricane or national disaster, all I'd have are a bunch of lithium 123As and about 50 alkies. Since I've never used alkalines in my L2D, I don't know what to expect. I also have a P3D, so that's another reason I'm not sweating the lithium AAs.

Thanks.
 
All the specs give for that light are with alkalines and going from that it should do great!



Features:

* Utilizes a Luxeon Rebel LED with a life of 50,000 hours
* Two modes of output, selected by turning the bezel (patented)
* General Mode: 11 lumens (55hrs) -> 50 lumens (10.5hrs) -> 100 lumens (4hrs) -> SOS
* Turbo Mode: 175 lumens (2.4hrs) -> Strobe
28 days of survival use (2 continuous hours per day on the lowest setting)
* Digitally Regulated for Constant Brightness
* Uses two 1.5V AA ( Alkaline, NiMH, Lithium ) batteries (not included), inexpensive and widely available
* 14.7cm (L) x 2.1cm (D) ( or 5.8 in (L) x 0.8 in (D) )
* Made of aircraft grade aluminum
* Durable Type III hard anodized finish
* 56-gram (or 2.0 oz) weight (excluding batteries)
* Waterproof to IPX-8 Standards
* Toughened ultra clear glass lens with AR coating
* Push-button tail cap switch
* Capable of standing up securely on a flat surface to serve as a candle
* Batteries not included
* Includes a holster, a lanyard, two spare o-rings, and a rubber switch boot
 
I also found this and wondered if it's a good deal. Fifty-two (52) Duracell Pro-Cells for $30. Looks decent.

Added: Ah, with closer reading, they're mixing alkies and lithiums. Nevvvveeeer mind.
 
All the specs give for that light are with alkalines and going from that it should do great!



Features:
* Utilizes a Luxeon Rebel LED with a life of 50,000 hours
* Two modes of output, selected by turning the bezel (patented)
* General Mode: 11 lumens (55hrs) -> 50 lumens (10.5hrs) -> 100 lumens (4hrs) -> SOS
* Turbo Mode: 175 lumens (2.4hrs) -> Strobe
28 days of survival use (2 continuous hours per day on the lowest setting)
* Digitally Regulated for Constant Brightness
* Uses two 1.5V AA ( Alkaline, NiMH, Lithium ) batteries (not included), inexpensive and widely available
* 14.7cm (L) x 2.1cm (D) ( or 5.8 in (L) x 0.8 in (D) )
* Made of aircraft grade aluminum
* Durable Type III hard anodized finish
* 56-gram (or 2.0 oz) weight (excluding batteries)
* Waterproof to IPX-8 Standards
* Toughened ultra clear glass lens with AR coating
* Push-button tail cap switch
* Capable of standing up securely on a flat surface to serve as a candle
* Batteries not included
* Includes a holster, a lanyard, two spare o-rings, and a rubber switch boot




Those specs are for NiMH (all Fenix AAA and AA runtime specs are NiMH but only the L1T and L2T specify that now) but the lights do just fine on the low level and should get close to the listed runtimes on an alkaline........................

Check these runtimes for the Nitecore D10. http://www.candlepowerforums.com/vb/showthread.php?t=206178
alkaline actually beats NiMH on low level (granted, that's a low low).............
 
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I Have the older L2D as my primary EDC...

My understanding is that it's very efficient on low modes with any chemistry, esp. lithiums, and alks.
 
The L2D does surprisingly well on high and medium modes with alkalines. Turbo is a different story just take a look at the graphs.
 
The runtime charts for the L2D include alkaline cells.
Yeah, I looked at the chart and that was what was so disconcerting. Kirkland advertises itself as being as good if not better than other alkalines, and it also advertises that it doesn't use mercury. How Kirkland compares to other alkalines is a question mark. The lithiums look like they're worth the money, but I'm coming to the conclusion that perhaps abandoning AA entirely might be my best bet. As long as 123As are as available as they are, they beat the prices of the AA. Plus they're just as rechargeable.
 
Oh, one more thing.

The graphs refer to the pre-Q5 versions. Are there any significant differences with the Q5s?

I've given my last two L2Ds to family members who wanted them. This has driven me back to my P3D (which works just fine; I just don't like the shape as well). I use my light to peer into the dark recesses of computers, and the long body of the L2D makes it handy to hang in wires and so forth, or to situate in ways that make it more useful. So I always order another L2D.

Also, when giving as gifts, I hate giving a flashlight like the P3D, where you have to tell the person you're giving it to where they can get batteries. Knowing they can get AAs anywhere makes me give the L2D more often to friends. My family, after getting my L2Ds, immediately wanted some as gifts for friends. I just love the shape of the thing. It's not that it does a better job.
 
I have a huge lot of old style "Carbon Zinc" heavy duty Eveready cells.

They are obviously junk, compared to even Alks, and hold a fraction of Alks charge.

L2D will run on them, on lower modes.
 
If you abandon AA entirely, go for something cooler than 123s, like 17500 or 18500. Myself, I want a SureFire with 2x18650 cells. Save you a bundle on recharging. 123s will get expensive after a while.

I will EDC a 1xaa fenix however.
 
If you want to know if the L2D will drain Alkalines, I would say a qualified yes.

When I first got my L2D CE I connected the head to my lab supply just to see how it would do. I only took measurement with the light on low.

I found that it would not turn on below about 1V but if it was already running it would run much lower. At 1.2V it was drawing about 100ma. The current draw kept rising as I lowered the voltage. At 0.3V it was drawing 280ma. Any lower and I guess it drops out of regulation because the current suddenly drops to 70ma and the light turns off.

I tried two almost dead Alkaline cells once but wasn't watching close enough and missed it turning off. When I measured the cells one was -0.3V and the other was 0.5V - giving a net 0.2V. I think I missed the turn off because it happened so fast with the accelerating current draw.
 
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