12v battery voltage

[Ian and Lins]

Got a couple of motorcycle 12v batteries and wondered what the 'resting' voltage should be? I'm asking because I've got readings of 17.2 ish from all of them. I suspect my (very cheap) multimeter.

[lees]

Just checked my GSXR 1000 12.56v

[AdrianC]

SEVENTEEN?
Definitely duff meter.

They'd have been boiling away merrily on whatever charger took 'em that high, apart from anything else.

[California Dreamin]

It is possible to see 13.5 or more just after taking off charge but 17.2 volts
Basically all batteries will hold on to a residual (high reading) just after being disconnected from a charger, however, leave them for a few hours and this soon drops to a 'nominal' standing state of around 12.6 volts (lead/Acid) and slightly higher (12.8 - 12.9 volts approx) for newer sealed Calcium/Silver types.

Martin

[Ian and Lins]

Cheers all. suspicion confirmed really.

[richlaz]

I've never seen a 12v battery measuring over around 13.5ish (you normally don't get over 14v going in from the alternator)

[Oldiebut goodie]

I had one read 16+ v after a battery charger malfunctioned - it didn't do it much good as it was on for quite a while. Apparently that model of charger had several reports of that happening.

[Ian and Lins]

The ~17v reading is on three batteries (its an Aprilia RSV1000 so needs 'em) so I imagine it must be the meter.

[Ian and Lins]

Quick update. It's a digital meter and the battery was dead so put in a new one and getting a sensible 12v+ reading. Never had this with my old dial meter.

[richlaz]

Digital meters can often give strange results when battery dying