WOW
Justin, you said you “hope” to get 10,000 lumens from this light at 3A drive current? The LED is rated for up to 3.6A at 36V and up to 18,000 lumens. I don’t know what the normal curve is, but I think you should easily get over 10,000 lumens. I’m looking forward to seeing the build!
A conservative 10000 OTF. It all depends on that unknown converter. If it's true that a higher voltage input will help it to get a 3+ amp output, then it should do it easily. Time will tell. I hope I can get 4 amps out of it, but won't know till I get the led in and start testing.
Why did you choose a boost driver instead of a buck? Is there such a thing as a buck with ~36V out?
I’m sure there probably are. These were available and had youtube reviews and I didn’t really want to go with more cells. They were what I found when searching the net. Lots of boost converters, probably meant more for 12V automotive than anything else.
That makes sense. Thanks!
Updated the OP - 06/05/15
You wont be the least surprised about this but l dont know what your doing. It seems to keep me enthralled though. 
The battery pack with all the charging components looks like a real doozy.
This look like an interesting build, good luck 
I am sorry to hear you got unemployed 
Not your run of the mill mag mod.
Subbed
Great build as always, can't wait to see it finished.
Correct me if I'm wrong but this looks like protection circuit board (PCB), not a battery management system (BMS). This should work in charging mode but only with that charger that You bought that has a end cut-off voltage. BMS would work with any power supply with correct voltage. Hope You can provide status of every single cell in this battery pack after a few charging and discharging cycles. That would be very interesting.
PCM, but from what I read, besides balance charging, it also manages output, so that no one cell is getting very low. If one cell is lower, it “supposedly” balances the power to the other cells, but that may just be my lack of knowledge. I certainly don’t have a clue about these boards.
Very impressive.
OL, the best of luck with this build but even more luck with the search for a new job.
This build looks like it will really light the way!
Another OL monster in progress and it's going to be more powerful then ever. Love it.
Every time i see a new flashlight build by OL a popcorn comes to my mind
About this boost converter does it give constant current ? i had used converter like it called qskj also bought it from aliexpress and it was working perfectly
LEDs came in today. Photo in the OP. Hopefully I will have some testing done this week-end.
Justin, I didn’t know until I was looking at it on the PCT the other day: this CXA3590 takes over 42V to reach its highest rated current draw! But, it starts at ~35V on the bottom end. That is a HUGE jump! If a person wanted to, they could use 10X 18650 or 26650 cells with a DD/FET driver (assuming the driver can handle up to ~42V input/output) to power one of these. I know that’s not what you’re doing with this light, but maybe the other CXA3590 could be powered this way?