
Hi folks. I have an unbranded light I bought from Lee Valley Toolworks some years ago. It has a battery holder with a magnetic base and about 2 feet of flexible gooseneck with an adjustable/magnifying LED light. The base takes a Cylindrical “Triple” AA battery holder that puts all the batteries in series … so about 4.2 V. The cylinder measures 3 cm x 6 cm.
I’m wondering if there’s a protected LI-ION battery that I can use in lieu of the 3 AA batteries/holder to get a wickedly long run time. Thoughts?
Thanks!
by NC12S-OBX-Rocks
4 Comments
A protected 18650 or 21700 should work depending on size, maybe 26650 but those are in a technological dead end
And a pic of the light …
https://preview.redd.it/6ovqwwo6xnrg1.jpeg?width=3792&format=pjpg&auto=webp&s=963b0cf8ad80680bd5e19cb33782f294ac08d11d
I’m not quite sure I’d be super trusting of an unbranded light meant to take alkalines (or maybe NiMH like Eneloops) to properly handle a lithium-ion. If it CAN handle that, one thing you *could* do is use 3 14500s (the lithium-ion equivalent of AA) in a *parallel* 3 AA to D adapter. Using 3 Vapcell F15 14500 cells would give you almost double the watt hour capacity over alkalines, and that’s *before* you account for the high alkaline internal resistance that makes them cripple themselves at high current draw.
Even with a roughly matching voltage, the light might rely on the internal resistance of the (weak) batteries to limit the current. Using a Li-ion battery might end in a short flash followed by endless darkness …