I am planning to get the EMISAR D4. I know people recommend using high drain 18650. If I don’t want to that power, can I use laptop pulled 18650 and still get decent performance? Thanks.
Sure, just keep in mind that if you use high output you will be sort of torturing the cell, reducing its capacity and lifespan.
Edit: So unless you have battery pulls you want to use its better to just throttle down the power.
The D4 will provide decent performance no matter what kind of cell you use in it.
The downsides of using a mediocre battery in it are:
A. Won’t get the best performance.
B. While on high load, the bad cell will have big voltage sag.
C. As a result the cell’s capacity (at high load) will be way less than the advertised one.
D. Cell might severely overheat.
I use Sanyo GA, and I only charge to about 4.0V. Max output is a lot less, which is quite noticeable because the light does not get super hot quickly. Cell is also not strained more than usual I believe.
Sanyo GA has too little amps for the XPL-HI Emisar, it chokes on it.
you will just give up the highest output levels
it may be worth it if you otherwise like the light, - quality, good UI, color, feel, etc
i certainly don;t use $10 cells just to get the last 200 lumens out of say, my astrolux S1
but i like everything else about it
Just don’t be cheap and use quality cells like Samsung 30Q or Sony VTC6. You will get the best performance. The D4 is a great flashlight, you will love it 
I was thinking about being cheap. I pulled like 20 laptop batteries. Want to make use of them. 
it might act weird but no big deal, you could get one expensive cell to show off with
then use the freebies the rest of the time
wle
I have some 30Q batteries, but Most of my sells are Panasonic 18650B or laptop pulls.
I tend to keep a better battery in my best lights just in case I need it, but the crappy cells are fine for 90% of what I do with the flashlight. You should eventually invest in one or two good high drain cells especially if you spent more than a few seconds on turbo.
I get that, but what’s the point of spending money on a high output quality light like D4 and then feeding it leftovers?
Why not save the money and get a Convoy S2+ or alike?
Akin to buying a Maserati and running it on 87 octane fuel.
Just did a test on my D4(3 xpl-hi 5000k) LG HG2. On start up 4000+ lemons. Settling at 3700 lemons at about(15 seconds) as long as it took to write down 3700. Another 20-30 seconds it was under 1000 lemons.
I let it cool a bit and installed a laptop pull (samsung ICR 24B).
At start up it was 3300 lemons in about 15 seconds it was down to 3000 lemons and another 20-30 seconds it was down to 2700 lemons.
My light is modded, so I would only consider the start up outputs against each cell.
The laptop cell started out lower but stayed longer. Both have there uses.
Man, you have lots of lemons.
Something I’ve been wondering about is reflashing the code to reduce the max ramping brightness to a level where it doesn’t get quite so hot.
I’ve been thinking the same thing.
Anduril is the UI we need. Gotta get the flashing equipment then figure out how to use it and do it. I figure set the max ramp at just below the level where it would burn a hole in my pants if it turned on in the pocket and ramped up. I could still activate turbo by double-clicking while on.
Done it. I am running a 3 channel Lexel TA driver 1—3+fet. Adjusted the ramping tables so I have about 550 regulated lemons at the ceiling. Fet only comes on with a double click. Ceiling configured from 1-5 clicks to adjust the pwm levels on the FET.
I just found this thread which seems to have some useful information.