14500 Charging vs AA

Why do the 14500 batteries charge faster? Does lithium allow faster charging compared to NiMH AA?

What are you charging your batteries with and what batteries in particular are you charging?

It could be because the 14500 has less mah than the nimh AA.

Trustfire 14500 900mAH charged with a Xtar MP1S. And the AA’s are Eneloops

Have you tested the mAh of those trustfires? Usually it is much less then claimed and written on it

+ 1 what The Miller said and you also have not stated what you are charging the Eneloops with.

Make sure your charger is compatible with the voltage & chemistry differences.

Sanyo NC-MDU01 to charge the eneloops at 850mA each cell.

Yeah there you go
850mAh vs “Ultrafire mAhs”
If you don’t have analyzing charger the time it takes is an indication. So if the Ultrafire takes half the time they have roughly 400mAh, still pretty decent only 100% extra mAh claim :wink: one can expect 10-25% of claimed “Ultrafire mAh” to be real mAh so +/- 80-200mAh in there.

AA nimh is 1.4V ~2500 mAhr, 14500 liion is 4.2V ~800 mAhr, a nimh would need 3x the charge current to charge in the same amount of time. Not a requirement but suggested charge current is based on a fraction of capacity in amp hours rather than watt hours which varies by cell chemistry and manufacture so even though the power capacity for the two is similar the suggested charge probably wouldn’t be. The charger should list the charge current for each cell chemistry with possibly a few choices for each in order to best accommodate different cell sizes.

I often charge my AA Eneloops at 2A, which is a 1 hour charge. That is with a Panasonic charger designed for Eneloops. I have seen tests at 4A charge, and they seem to handle that okay, though I personally wouldn’t recommend it.