Date:         Tue, 15 Mar 2011 07:39:26 -0700
Reply-To:     mark drillock <mdrillock@COX.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         mark drillock <mdrillock@COX.NET>
Subject:      Re: Auxilliary batteries
Comments: To: David Beierl <dbeierl@ATTGLOBAL.NET>
In-Reply-To:  <4d7ed632.9279e60a.5c15.2cc4@mx.google.com>
Content-Type: text/plain; charset=windows-1252; format=flowed

I have a simple setup with a 1314 and the 125ah led acid deep cycle. The
aux battery sees about 14.5 volts while I am driving. My battery did not
experience any loss of water but it did lose at least half of it's rated
capacity in less than a year. Whether this problem is due to charging
method or simply a poor battery is a question I would like to answer but
can't.

My current plan is to put in a switched voltage drop to let me reduce
the charging voltage on long drives, after some initial period of full
voltage to allow fast charging. I plan to use a big diode for the
voltage drop.

Mark



David Beierl wrote:
> At 10:04 PM 3/14/2011, Daryl Christensen wrote:
>> OK…My van charges at about 13.6 to 13.8 or9 max. All the spiffy
>> temp/voltage AGM battery chargers I see are 120V AC input..
>> Is there an onboard “charger widget” for upping the charge voltage to
>> the 14.4 the AGB batts need?
>
> Yes, but you're not going to like it. Because getting up there is easy
> (at least on Bosch alternators) - drop-in adjustable regulators are easy
> to get. It's getting back down that's the problem, 'cause if you keep
> the voltage up there you'll boil the thing dry.