I haven’t had much luck with lithium primary AA’s left in a car, either. I thought they were supposed to be good with heat & cold, but I find regular alkalines last longer in a car. You might be best just replacing the batteries a couple of times per year. Or, use Eneloops, and take them out and recharge them once or twice a year. (Eneloops are much better in the cold.)
I have a couple of those lights, and they work, though not very bright. I don’t think I’d trust that the mechanics wouldn’t break if I used them a lot. Also, there’s a lot of energy in just a single AA battery, which would take hours of cranking to equal. Finally, size is a concern in a BoB.
I think a 1xAA light with a moonlight mode, will produce light longer than someone would ever need.
there is one selling on ebay for about $20 but it’s not a flashlight. A very small joule thief. Micro joule thief kit. I don’t want to post a link here.
It doesn’t use a 5mm led. Thinking about getting that and a D cell holder with wire and solder the wires together. just pop in the battery and it’s good to go.
I second the Inland R22. That little driver will start on as little as 0.7V and once it’s running keeps on going with moonlight levels until about 0.3-0.4V. Been hooked on this light since I got my first one on recommendation from Lightbringer.
You can even swap the emitter and optics in the host with a standard 16mm MCPCB and 20mm optics or reflectors.
You can use a tiny gated oscillator like a YX8018 or QX5252F to make a flashlight instead of trying to figure out joule thief. It’s even more simpler and only uses 2 components (Gated oscillator and an simple inductor). No toroids or transistors or resistors needed. You have the advantage of current control and additionally you can also charge your battery with a solar panel if needed.
Update:
If you really insist then there is this DIY joule thief flashlight kit available in ICStation store on Aliexpress for 2$.
