Best 14500 cells for Fenix LD11 ?

Hi! New here.

This is not entirely "battery-specific", so I hope I did the right thing by posting in this forum.

So, in total, I've had 5 or 6 flashlights (and 1 headlamp) made by Fenix. So far I've been doing just fine with the standard AA and AAA batteries.
However, now that I'm about to get the LD11, the time has come for me to step into the Li-ion world. Since I am completely new to this kind of cells, I have a few questions:

1. What's usually the shelf life (approx.) with the 14500's? And by "shelf life" I mean: how long do they stay charged when not in use? Days? Weeks? Months?
2. Which brand should I buy for the LD11 flashlight? And this is a big one....

First of all, from what I understand, not every type of 14500 cells can be used with the LD11 because of the weird thing Fenix have done with the positive terminal contact. Which means that the flat-tops are out. Unfortunately, this kinda limits my choice but does it really? Because I simply want to get the best 14500 cells for this flashlight (and my requirements).

a. Longest stand-by time: Cells that retain their charge the longest (when not in use). This is not my top priority but it is up there.
b. Highest capacity (longest burn time).
c. Best voltage for the LD11. I've seen ones that are 3.6V, 3.7V, others that are 4.2V... And I don't even know if it would make any difference in the LD11. I'm new to this, so, sorry for the stupid question.
d. Protection circuitry. I know that this feature may somewhat limit the cell's capabilities but it is a must.
e. Longest battery life. I don't want cells that expire after 2 years of "no-use" or just 50 cycles.
f. Price: Any (within reason). I want the best, premium stuff, as long as the price isn't "stupid high". *I need a pack of at least 2 but preferably 4 AA, 14500 cells.
g. Availability: Online, preferably ebay but I am willing to go the extra mile to get what I need from wherever else.

3. What about the charger? I was thinking about getting the ARE-C2 from Fenix but obviously, I need a charger that knows how to handle properly the type of cells that I'll have. In any case I'm looking for a good charger that can charge at least 4 cells in one go.

4. And since this is the flashlight forum: What does the "G2" stand for? On Fenix's site it's the "LD 11 G2", while everywhere else it's just "LD 11". Are there any variations of this model?

Sorry if some of the questions are stupid.

Thanks.

Look at the manual for the light very closely. They may list a cell length limit for the 14500 cell option. Some makers do that which saves a lot of headaches. The G2 denotes the XP-G2 emitter type that is in the light. This LD11 has one of the latest versions, the XP-G2 R5, which is a good thing. I looked on the Fenix site it does not denote 14500 cell size limit. Safest bet are 750mah 14500 cells from Fenix, Keeppower and Olight. They are protected cells with button tops so they will work in the light and are pretty much a lock on not being to long like an 800 or the 840mah protected 14500's that are around the 750mah cells will average 52mm long. I bought 4 840mah Keeppower protected 14500's and all 4 showed up at a to long for just about any of my lights that take this cell type 55mm despite being advertised at 52.5mm. The Fenix cell will be the most expensive of the 3 I listed its an excellent cell but youre paying a premium for the brand name. Keeppower 750mah and Olight 750mah should be below 10 bucks each.

When it comes to AA primary cells Energizer Ultimate Lithium AA L91's(thats their model #)are as good as AA primaries get. They are 3000mah per cell and crank 1.5v right until they die. But of course max output calls for 14500's. The LD11 is a lower output light so even the low capacity 14500's should last in the light an average nights worth of max output before they need charging again. The L91's hold over 3 times as much juice just at a lower voltage youll get far more runtime with them just at a lower output level.

Charger-I myself use Xtar chargers. Their build quality is usually better than the Nitecore range. Idk much about the Fenix chargers I am sure they are good though. Just think of if youll be getting any more lights as you can get most multi chem chargers in 2 slot or 4 slot versions. I use Xtar 4 slot VC4's. There is also a 2 slot VC2 available.

Battery life all depends on how often you use the light to the point of needing to charge the cell again. For example the 750mah cells I listed are solid for 300 recharge cycles. So if you use the light every night you should get about a year out of each cell.

The 14500's say 3.7v because that is the lowest usable voltage rating that is how these cells are rated. They charge from 3.7v out of the package to 4.2v full. The LD11 has a mechanical switch not an electronic switch that draws current even with the light off. These cells hold their charge very well when sitting in the light when it is off.

These questions are not stupid feel free to ask anything light related here. From what I know there is an older LD11 the G2 is the newest version.

Shelf life-my 750mah 14500 cells for example I charged 2 Olight 750mah cells to 4.2v almost 2 months ago. I just put them on the charger and they came up at 4.17v so they have very good shelf life.

G2= generation 2

One other consideration. Not only are the higher capacity cells longer, they are also much more expensive. Usually one will see a significant price break by going for the next to highest capacity cells. The only reason I would ever buy the highest capacity cell I could find would be if I absolutely needed the most run time possible in a situation where it would not be possible/advisable to have to change cells while in use.

PS: The reason higher capacity cells will likely be longer is because that is the only option manufacturers have. The chemical makeup of the cells doesn't change, so to get more capacity a cell needs more content. Since the diameter is constrained by the diameter of the cell holder, the only option to make room for more content is to make the cell longer.

I just purchased a bunch and Xtar came as the best balance of cost economy and capacity (tested by lygte-info.dk). They were $4.50 each.

Wow, am I glad I came here!

I didn't think much of the "G2" in the model name. And I almost didn't ask about it. I'm glad I did because I would have made a mistake.
Thank you all so much for replying and educating me. I am learning a lot and there is a bunch of stuff to process. Now I need to do an in-depth research, based on the newly acquired information but I feel like I'm finally getting somewhere.

I have been using AA and AAA Energizer Lithium cells almost exclusively in all of my Fenix lights. They're the best but they can run you into a potential problem. You can read about it in my reply to this thread:
http://www.candlepowerforums.com/vb/showthread.php?423941-Fenix-HL35-review

Anyway... Like I said, I need to spend some time checking out specs and comparing prices but it looks like I've got the basics covered.

One more question (and probably not the last):

Basically, I'm need the LD11 G2 to replace my E21 flashlight which has been an excellent companion to me for a number of years. The reasons for the switch are the reduced bulk and weight, period. Other than that, the E21 is perfect for what I need to do with it.
The output that I get with the E21 in the High mode is right on the dot. The beam has a nice hot spot which gives me a very decent (and also needed) reach in the mountains.
Unfortunately, the output of the LD11 with regular AA's is not that great. So, the only workable type of batteries in my situation are the 14500's.
Being used to the non-rechargeable Lithiums that I can just grab and use whenever, EVERYTHING about the 14500's, to me, is a major pain in the rear. So, the hassle better be worth it.

And so my question is:

With the LD11 G2 and the best 14500 cell, will I be able to get the same (or better) amount of reach that I'm getting with my E21 flashlight?
*The shorter burn times of the LD11 are within the range of my requirements.

I've seen a video on youtube that demonstrates fairly well the type of throw on the LD11 and it looks very similar to my E21... There is the nice hot spot that I'm looking for. But then it's only a video, so I had to ask.

So, I don't know... Maybe someone who actually owns an LD11 can chime in.. I'm pretty sure the beam pattern and the light output are indeed what I'm looking for but it never hurts to get a second opinion.

Anyway, thanks again!

I don't have a E21 but I do have a LD11 that I run on either Fenix 14500s or Efest 14500s. The price differences and mah ratings for the batteries are negligible.

As for the light itself, I really like it. It's a great light that can run on AA, eneloops, or 14500. It's small but puts out big power. Great edc light. Plus, it's small enough to hold in my mouth when I have my hands full--such things are important when your other hobby is vintage racing.