I'm thinking, from what I see, that the LED, star, Heat sink, Driver and contact plate will have to be inside the body.
If I add all that up
- LED/Star - 3mm
- Heat sink - 15mm
- Driver - 8mm
- Contact plate - 4mm
So, I am looking at about 30mm. If I go with 65mm as the starting point, then it only leaves me with 35mm room for batteries. That's not a lot of room for batteries and it leaves me with my first thought (2/3A NiMHs). They are only 1600mA, but they are 10C batteries, so they will take high drain. 4 of them would work well for the XM-L2.
But..... if I go with a shorter stack up, the obvious thing is to cut back on the heat sink, go with 10mm thickness and make it a tight fit in the body, (no small chore when you think of the clover leaf opening in the body).
- LED/Star - 3mm
- Heat sink - 10mm
- Driver - 8mm
- Contact plate - 4mm
Gives me 25mm, so it leaves 40mm room for batteries. I can also get 5mm more if I use shorter springs, so that would give me a total of 45mm room. Now, let's look at what choices I have.
RCR123A - 17mm x 34.5mm not much power there 900mA max and that's asking a lot, but with 4 in parallel, it might work.
18350 - 18mm x 37mm at 1200mA and with 4 in Parallel it gives me plenty of power.
4/5A NiMH - 2000mA and I don't see the High C rating, so I assume not more than 2C. Still, it might be ok.
I am just showing you what I go through when I look for what battery configuration I am going to use on a light and of course I favor NiMHs. I usually use two sources for battery dimensions Wiki and Allbattery.
I am really tempted to go with the 2/3A NiMH due to the High C rate, but what do y'all think about it?