Battery Voltage

[sparkie]

Hi all, I know this question has been asked and answered before, but the Forum search facility is out of commission at the moment.

What should a fully charged, a partially discharged and a flat battery show when tested with a simple voltmeter? Mines showing 12.55 at the moment and I suspect it should be higher.

Cheers

Sparkie

 

[mormargh]

http://www.ybw.com/forums/showflat.php?C...rue#Post1826114

A whole 3 days ago.

 

[VicS]

Different souces give different figures. They vary between battery types and with temperature anyway and there is a wide band that can be applied at both fully chahrged and completely discharged ends which the graph from the Voltwatch indicator site shows
I use 12.7V fully charged and 11.7V effectively flat a convenient 1V difference making estimating % charge easy. Both are measured after 12 to 24 hour rest without charge or discharge. (Wet lead acid batteries)

There is a link to an excel spread sheet of data which may not be in the link already given mentioned at www.batteryfaq.org


PS the search is working but it does not work from the bottom of the index page, you mst use it from the top of the pages

 

[sparkie]

Thanks both, looks like there's life in the old thing yet. I'll print off the graphs etc so I don't have to ask the same question again in six months time............

Cheers

Sparkie

 

[reeac]

The old mnemonic states:
12.7 you're in Heaven
12.5 still alive
12.2 lots to do.

That's accurate enough for most purposes.

 

[sparkie]

I like that. Useful for auld gits like me. Cheers.