Hi all.
I need to find a (17mm) driver that will support a single 1.2v-1.5v AA battery, and that will also support a 3.7v 14500 Li-ion battery. I’m looking to power an XP-G2 LED (to moderately high levels preferably). Any such critters out there?
Short of that, any drivers that will support just a single 1.2v-1.5v to drive a (XP-G2, XM-L2 etc) to fairly high levels? I’d be using an Eneloop Pro or Energizer Ultimate Lithium Primary cell.
Many thanks, J&H.
Anyone?
Is it just too large a voltage range?
Maybe I need to have a go at disassembling one of my Preons?
Beginner here. Any and all info welcome. 
Thanks,
J&H
Don’t know if this will be bright enough for you…
Or this one:
https://www.fasttech.com/products/1612/10002000/1143101-1-2-aa-aaa-1-18650-1-mode-1a-led-flashlight
I went to 14500 only on my AA sized mods… More mode and driver selection available. I lose the AA/Eneloop ability, but not a big deal to me.
HKJ has tested many of the available drives here: http://lygte-info.dk/info/indexLedDrivers%20UK.html
Just pick the one you like
Thanks for the suggestions. Yeah, looking for excellent output on high with a 14500, with a decent medium setting. And decent output on high with an AA.
J&H
Thanks for the link. Wish there were more .8v - 4.2v drivers around.
J&H
It’s a combination that is fraught with compromises. It needs to boost 1.5V AA and yet survive 4.2V 14500 and that in combination with the small driver size limits what can be done. ~800mA-1A is about it for LED current and isn’t optimized for both cell types. Alkalines suck at supplying that kind of current(more than twice led current) and boost drivers typically go direct drive when battery voltage is above LED voltage. A high drain imr cell could easily poof the driver and efficiency when using pwm to get lower modes from DD current is not good. If you’re ok with the compromises then by all means do it. I have a Thrunite Saber 1A with this type of driver and like how handy it is but run time would be better with a driver matched to one type of cell. A 14500 matched to an fet driver can easily supply 2A or more to the LED without straining either the cell or the driver but won’t work at all with a 1.5V cell. The Nanjg110 is a boost driver and there are 15mm versions out there as well as a thread running on a project to add an Attiny 13A for modes to a custom driver pcb but it’s only available as a DIY project.
This is what makes me wish for drivers in tailcaps — switch the tailcap along with the cell — NiMH, Li primary, or NiMH.
Instead I find myself color coding my AA lights (SK68s and #3 zoomies) as a reminder which kind of driver’s in each one, so I can lend them out.
The most powerful boost drivers I have are salvaged from upgraded, junked and cannibalized 1 x AA zoomies, such as SK-68 clones, SK-58s and especially #3 zoomies as these are cheap and new. They are however 15 mm. I thought 17 mm. boost drivers were only for CR-123A lights, and even the one of those I am working on prefers 15 mm.
These all work with 1x/2x/3x AA or 14500 or CR123A.