However , the Air does not indicate its power level, only 'good' and 'no good', so there's no real way to cut off the power as you suggest, without using an intelligent charger that shows voltage as its charging, like the nitecore d4.
As it's been discussed before, vaping while charging will end up in system failure, so, I really recommend a separate charger so you can always have one charged battery ready to go.
Yes, you can discharge the Air far enough to hit cutoff, try it and see. I can't speak to colors, but there is a real cutoff. It's about 55 minutes out from 'full', give or take. At that point you need several minutes on charge to get going again. It takes about 2050 mAh of charger current to bring it back to full. Presumably that level is set at a safe level, at least for the factory battery.
I sure don't agree with "the red 'discharged' light on the Air kicks on at or below 3.49 volts.
This is way too low for most 18650 batteries" as I said, I don't know any Li-ions with lower limits that high. Consider this popular 18650:
http://industrial.panasonic.com/www-data/pdf2/ACA4000/ACA4000CE240.pdf
The chart upper right clearly shows we still have over a third of the useful capacity at 3.5 Volts. E-cigs typically regulate to 3.2 or so for this very reason (longest safe run time from their Li-ions), that seems logical here? Do you have an example of any Li-ion that's not safe discharged to 3.5? TIA
You can actually use current sense to detect the shift from CC to CV with the internal charger, I've been doing it with Solo for a year or so, the current one looks like this:
It's tripping about 650 mA IIRC. That's 12 VDC, of course, so you need a regulator to work with Air (5 VDC) my original looked like this:
Since the currents at normal charging levels (discharged battery) are basically the same for Solo and Air (about 800 mA max) the settings I've been using for Solo work fine for Air. The internal charger stops about .1 Volt early, about 10%, say six minutes run time? I still get four full sessions (I count 'em), and need around 1900 mAh to recharge. It can be done.
I don't agree that charging while using will end in failure. It's leaving it fully charged that's the issue. IIRC the charger can supply about 40% of the needed power, since it's a Norton node current summing game current from the charger doesn't have to come from the battery. That means it doesn't have to be replaced later. So the battery is discharged and recharged less. This will actually make the battery last about 40% longer
if the owner is careful to avoid full charge as a matter of routine......which I think most would if they got into the habit? That (full time 'charged, ready to go') is what typically kills cell phone and laptop batteries. I'm sure we all know of such devices that no longer run very long, that's probably why. Not a good feature in a portable vape I think.
Confusing stuff for sure, but that's my understanding of the rules.
Regards to all.
OF