Don’t chargers monitor the terminal temperature to determine when to shut off? (I know lithium profiles don’t, but the chargers I have with lithium profiles monitor temp and stop charging if it goes over a certain temperature)
Some manuals I’ve read for chargers with adjustable current say not to use too small a current as it doesn’t generate a big enough temperature rise to end charging.
Definitely something new that I haven’t seen before though. Where abouts did you buy them?
These adapters is for Nickel based (NiMh or NiCd) cell, as its only fit for C or D cell, don't think its common to see Li-Ion type in these sizes.
Charging process use the usual primary full charge detection algorithm which most good smart desktop charger have, using the usual voltage plateau (Negative Delta V / NDV) detection as full charge sign, of course as long the user doesn't charge it at too low C.
Most smart chargers capable of pushing 2 or 3 Amp current, which is enough for these > 3000mAh cell. Although at the photo I used is the old popular Powerex MH-C9000, as it happened it was within my reach, I used SkyRC MC3000 most of the times, which is much better charger, and it works flawlessly.
Even though most modern Ni-Mh based desktop smart charger does monitor temp, as "part of" the protection mechanism, yes, this adapter simply made thermal sensing (delta temp in Ni-based) useless, time out protection mechanism is a must for the charger in this case for overcharge protection.
Acquired them thru AliExpress.