Re: Estimated ARC AAA runtime with new AAA lithium
Since the Arc AAA circuit is the same as the Arc AA's (from what I heard), its behavior should be similar to an Arc AA with an L91 battery. Thus, brightness should be about the same as with an alkaline of the corresponding size, but with a flatter curve as the battery discharges. Runtime should be a bit longer but not spectacularly so.
The Arc AA and AAA already overdrive their LED's considerably. Making them even brighter is probably asking for trouble. If it were me, I'd back off the drive current a bit, certainly not increase it. If you want a brighter light, use a Luxeon.