On 18/10/2011 02:45, RussellMc wrote:
> The batteries will never charge fully.
> If only 5V was available you will get either only relatively uncharged
> cells or you will need to charge portions of the pack separately in
> some manner.
> At under about 1.35v x 4 =3D 5.4V you probably don't need charge
> termination as the cells will trickle to a full stop without being
> fully charged.

At 4.76V as Russell says the batteries hardly charge at all.
For quite a while on 24mA load I measure NiMH AA as being > 1.3V  (four=20
is thus 5.2v)

Likely 5.6V approximately is a minimum charge voltage. But for any=20
reasonable charging maybe over 6V supply is needed.

It's somewhat temperature related.

The "traditional" 1.2V quoted is
1) A nominal kind of average over most of discharge time of NiCd. Not an=20
actual voltage of fresh battery.
2) NiMH are slightly higher terminal voltage. Maybe about 0.1V to 0.15V,=20
but it depends on where you decide the "end point" is.

You'll get two different voltage readings for no current and charging=20
current for a nearly charged cell.
--=20
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