L2D Lithium

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schwim

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Hi all, new to this cool site. Just ordered a Fenix L2D CE and can't wait for the shipment. Did a search and found that Energizer makes non-rechargable AA Lithium batteries. Will these work in this light? Will they provide higher lumens than alkaline bats?
anyone.gif
 
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The L2D is current regulated so no matter what AA cell you use, it will be the same brightness. NiMH AA cells will give the same brightness as lithiums but not run as long. Alkalines will probably give a short runtime due to the high current draw which that chemistry does not stand for long.

Lithium AA cells are a great choice if you use the L2D on rare occasions or as a long running emergency light. If you use the light all the time, NiMH rechargable AA cells will give you the same brightness and much longer runtimes than alkalines.

Enjoy your L2D CE and aim away from face! :)
 
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They will work but they wont provide higher lumenes, just longer run times as its got 3000mAh capacity as apposed to the the 2800 mAh average of Alkalines Lithiums also have a 10-15 year battery life.
 
The Energizer 1.5 volt lithium AAs should be fine, but they won't provide more brightness - only (slightly) more runtime. You'll have to decide if they're worth the increased cost over alkalines or NiMHs.

DON'T use Li-ion 14500 batteries, though. Although they are physically the same size as an AA cell, they are 3.7 volts each. While one of them would be fine, two of them together would supply too high a voltage with potentially disastrous consequences for your Fenix.
 
The Cree 7090 XRE input voltage is somewhere around 1-9 volts so 2 14500 batteries may actually work with the L2D (at your own risk). I have the new Huntlight with the same Cree and I use 2 RCR123 3.6 v batteries which is okay with Huntlight also. The circuit boards may be different so this may cause damage to the L2D circuit. I'm sure somebody will try it tho.

As it has been discussed here, LED's can be overdriven with the known risks of shortening the life of the LED and possibly burning out the circuit.
 
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light_emitting_dude said:
The Cree 7090 XRE input voltage is somewhere around 1-9 volts so 2 14500 batteries may actually work with the L2D (at your own risk). I have the new Huntlight with the same Cree and I use 2 RCR123 3.6 v batteries which is okay with Huntlight also. The circuit boards may be different so this may cause damage to the L2D circuit. I'm sure somebody will try it tho.

it has nothing to do with the led, and everything to do with the circuitry.. i would NOT try 2 14500s.
 
light_emitting_dude said:
The Cree 7090 XRE input voltage is somewhere around 1-9 volts

Why do you say that? Have a look at the I/V graphs. If you apply 9V to the led you will have a huge current through it and the led will be destroyed inmediately.
 
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light_emitting_dude said:
Why? because I read it here. Read post # 34 this thread.

http://www.candlepowerforums.com/vb/showthread.php?t=147329&page=2&pp=30
The input voltage of the flashlight's circuit might be 1-9V indeed, but that is not the same as the input voltage of the LED. The maximum current of the Cree XR-E is 1000 mA and that is already reached at around 3.8 V. Anything above that might kill the LED.

Please edit your post above to avoid confusion and possible damage that might result from it.
 
Like I said, "at your own risk" I tried 2 14500's in my Minimag LED and it would not turn on. Must have overvoltage protection in the circuit.
 
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schwim Welcome to CPF,
The Fenix L2D CE was a good choice,
looking at the specs its got it all,
I can't wait to get mine
 
lithiums will not give the same high output, as they cant stand the current draw.
Stay with Ni-Mhs or Ni-Cads for that
 
light_emitting_dude said:
Like I said, "at your own risk" I tried 2 14500's in my Minimag LED and it would not turn on. Must have overvoltage protection in the circuit.
light_emitting_dude said:
The Cree 7090 XRE input voltage is somewhere around 1-9 volts
You don't understand. The following are 2 different things :
- input voltage of a flashlight
- input voltage of the XR-E LED
Why? Because there is a driver between the batteries and the LED. The driver might have an input voltage upto 9V. Then the driver adapts the voltage to a suited level to drive the LED, and that is maximum around 3.8V.
 
light_emitting_dude said:
Like I said, "at your own risk" I tried 2 14500's in my Minimag LED and it would not turn on. Must have overvoltage protection in the circuit.

You are not even speaking about the same flashlight! Every one has a different regulator circuit with different value ranges. Some have protections, while some others don't. Other Fenix flashlight have regulation circuits which admit up to ~4V.

Anyway, don't directly feed the led (if you apreciate it) with any voltage greater than 3.8V as Erasmus stated above.
 
Any newbies reading this post listen to ERASMUS or you are going to end up with a fried driver or LED or even both. Manufacturers give the min and max voltage for a reason and thats so there lights dont get fried.
 
Getting more and more tempted to buy rechargable lithiums. How would the runtime be on L2D running on 14500s? Same, shorter or longer?

And another question, cr123 are 3,0, so in theory all 2AA lights could be driven by cr123 with the exact same performance in brightness compared to NiMH AA? Or does the fact that it's lithium change anything? And I'm guessing the runtime gets shorter?
 
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did You not read anything that has been mentionned above? (except for light_emitting's EDITED)
or
have You not read ANY other Fenix tread?
:(

just for Your info:
2 Li-Ions in the L2D-CE have too much Voltage and will probably immediately kill the circuit inside!
probably because some of the Fenix' circuits seems to enter into "direct drive" when input voltage is higher than needed for feeding the led. So with 2 14500s I think, 1st the circuit will give full voltage to the led, which will die an immediate flash dead, then (with NO LOAD) the circuit will be killed.

DONT SAY YOU HAVE NOT BEEN WARNED IN CASE OF FAILURE


PS; answer to question: runtime thus will be shorter :evilgrin07:
 
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yellow said:
did You not read anything that has been mentionned above? (except for light_emitting's EDITED)

:awman:

This is inappropriate language here at CPF. You should consider editing your post. I'm just a noob here and still learning. I just simply stated a theory and I am not deliberately trying to get anyone to fry their L2D. Ease off the large and bold text, I think most of us can read here.

Does anyone actually know the input voltage of the L2D circuit? I can't seem to find it. I would assume that it should be somewhere around 4 volts to the circuit. I use a 14500 in my L1T and will do the same in the L1D.
 
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You are not able or willing to CHANGE ALL YOUR POSTS IN THIS TREAD HERE and seem to not understand that YOUR NOT CHANGED POSTS IN THIS TREAD HERE will lead to immediately destroyed lights of "beginners",
just read what Lobo thinks to do,
only entering a "(do at Your own risk)" is a bit lame, dont You think?

So please dont bother ME with inappropriate language
(I really tried not to type anything concerning Your above posts, but the ones like Lobo's and Your constant ignoring that You are much more than wrong just made me angry, and I will not make an excuse, if You wait for that)
Also I am absolutely certain any inappropriate language will find a very quick reaction from the moderators in here.

input voltage is 4 Volts max, there are only a few dozens treads here, where people like "7777" typed this.
 
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light_emitting_dude said:
yellow said:
did You not read anything that has been mentionned above? (except for light_emitting's bullshit)

:awman:

This is inappropriate language here at CPF. You should consider editing your post.
Dude, not yellow but YOU should consider editing your post. It still states the wrong information as I told twice above.

light_emitting_dude said:
I'm just a noob here and still learning.
I am also a noob and still learning, but at least I am willing to edit my posts if I write some wrong information and someone learns me what is wrong and how it should be.

light_emitting_dude said:
I just simply stated a theory and I am not deliberately trying to get anyone to fry their L2D.
If your theory is wrong and we tell you that, then why don't you change your theory? It's like saying to someone to jump from a 50-floor building and saying it is at their own risk and they might get hurt. Well I can tell you for sure you won't survive it.


light_emitting_dude said:
Does anyone actually know the input voltage of the L2D circuit? I can't seem to find it. I would assume that it should be somewhere around 4 volts to the circuit. I use a 14500 in my L1T and will do the same in the L1D.
Maximum 4V as far as I know.
 
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