Date:         Fri, 19 Mar 2010 14:53:44 -0400
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: Normal voltage of a battery at rest?
Comments: To: courtney hook <courtneyhook@SHAW.CA>
In-Reply-To:  <f317b50333958.4ba352ab@shaw.ca>
Content-Type: text/plain; charset="us-ascii"; format=flowed

At 01:32 PM 3/19/2010, courtney hook wrote:
>1) What is a "healthy" battery voltage at rest??

Nominal full charge voltage for a lead-acid battery that has rested
for 24 hours and has no drains on it is right about 12.6 at
20C/68F.  Fully discharged under same conditions is about
10.8-11.0.  The float voltage you mentioned is correct (again at 20C)
for gel batteries and 0.4 volts low for flooded cells.

Specific-gravity readings corrected for temperature will be accurate
any time.  For voltage checks the battery must rest with no drains
for about 12-24 hours before testing.

Take a look at <http://en.wikipedia.org/wiki/Lead-acid_battery>

Yours,
David