Nimh cells charged voltage !!

What voltages are your NIMH cells coming off your charger ? Mine are reading 1.4v !! this seems very high !!


Sounds about right to me - older ones (knackered) can go above 1.5V. My Eneloops normally come off the charger at around 1.45V

O right these are brand new !! I was going to DD my XML but with these voltages i'm not so sure.. Even ms SST-50 starts to smoke unless i discharge the batteries a bit first.

Keep in mind that that is just the at rest voltage. As soon as you apply a load, the voltage will go down some. The voltage usually drops off pretty fast at first and settles in below 1.3V. But check the current at first anyway just to make sure you aren't killing the LED.

This is what I've noticed also. My batteries come off at about 1.45v and settles at around 1.30v to 1.35v so, since I have plenty of extra batteries, I don't have to use batteries that came right off the charger.

The voltage rating on the label refers to nominal voltage, which will be lower than the open circuit voltage at full charge. 1.4V hot off the charger is perfectly normal, and the cell will settle down a bit after a brief rest for it to cool and chemically stabilize. The normal range for NiMHs from discharged to charged is 1.0V to 1.4V, give or take half a volt.
Compare with Lithium-ion (3.7 nominal vs 4.2 open circuit) or NiZn (1.6 vs 1.8), for example.
Ideally the sag from load is supposed to bring the cell to nominal voltage during use, but as there’s no such thing as an ideal circuit you should not count on that property for protection.