Date: Mon, 30 Jul 2007 11:47:40 -0700
Reply-To: Michael Elliott <camping.elliott@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Michael Elliott <camping.elliott@GMAIL.COM>
Subject: Re: Deep Cycle Batteries
In-Reply-To: <BAY125-F403F2EBE490E94A7093ED1A0EE0@phx.gbl>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I gotta re-check the output voltage of my alternator. It's adjustable,
at least. Maybe I have it set too low. Dennis suggested 13.8V to me
quite a while back and maybe that's where it runs now. Memory, ah what a
fleeting thing!
--
Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
KG6RCR
Dennis Haynes typed:
> Ideally, the stock alternator-regualtor set up should be putting out
> 13.8 volts. Yes, they do drop a little after the alternator gets hot but
> that is the set point. Many cars push to 14 volts or more.
> The 13.8 is consered ny many battery folks to be the ideal compromise in
> fixed voltage systems for flooded batteries.
> Dennis
>
>
>
>> From: Michael Elliott <camping.elliott@GMAIL.COM>
>> Reply-To: Michael Elliott <camping.elliott@GMAIL.COM>
>> To: vanagon@GERRY.VANAGON.COM
>> Subject: Re: Deep Cycle Batteries
>> Date: Sun, 29 Jul 2007 22:28:09 -0700
>>
>> Proper charging of a deep cycle wants a proper two- or three-stage
>> charger (better). Good solar controllers do it, too. If I leave a
>> campground in the morning w/o first charging up the battery w/ the
>> panels, and rely on the alternator to charge the battery, drive a few
>> hours, then check the state of charge, the battery monitor generally
>> reports that I'm still 4 to 7Ah short of a full charge. This is with an
>> adjustable alternator set to higher than stock voltage -- about 13.6V
>> when temps are cool, 13.4V after driving for a while. Such voltages are
>> too low to bring the deep cycle to full charge. Our controller applies
>> current until the battery reaches 14.1V then chokes back the current to
>> hold it there. After the controller is able to hold 14.1V with less than
>> an amp for more than two minutes, the monitor declares the battery full.
>> These alternators are not so smart. But I'm not complaining -- getting
>> into camp with a battery that is 90% full is good enough for our use.
>>
>> And, as John said, Dennis knows his onions when it comes to this stuff.
>>
>> --
>> Mike "Rocket J Squirrel" Elliott
>> 71 Type 2: the Wonderbus
>> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
>> 74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
>> KG6RCR
>>
>>
>>
>> Geza Polony typed:
>>> Sorry to have hijacked this thread with my own aux battery probs, but
>>> I hope
>>> there's enough general info here for others to use.
>>>
>>> Interesting:
>>>
>>> On Sun, 29 Jul 2007 21:24:32 -0600, John <vanagonvw@GMAIL.COM> wrote:
>>>
>>>> if you
>>>> invest in true deep cycle batteries, and don't use a three stage
>>>> charger
>>>> to keep them topped off, you are not getting the max life out of it,
>>>> and
>>>> in fact, are never getting it "filled up" in the first place. It may
>>>> say
>>>> 100aH, but without the proper charge rates and controlled currents, you
>>>> won't see those numbers in real life. These are not 'starter'
>>>> batteries,
>>>> and are not made to be bulk charged, with a constant dump of current
>>>
>>> In other words, just putting the Optima (or whatever) in and
>>> connecting it
>>> to the relay, etc., is NEVER going to be enough to keep it fully
>>> charged?
>>> That sounds like the problem here--it's never quite fully charged. (This
>>> goes back even before my mishap with the espresso maker.) So to
>>> really get
>>> the max out of a deep cycle battery, you have to use a separate charger?
>>> I'll try it but sure seems like a PITA to have to do.
>>>
>>> If they're not made to be charged "with a constant dump of current,"
>>> then
>>> how can you connect them to our typical alternator/relay systems to
>>> good effect?
>>>
>>>
>>>> Just wanted to point that out....Dennis knows of what he speaks. Those
>>>> who are paying for true deep cycle batteries, who want to take care of
>>>> their investments, and get the most out of them, would do well to do
>>>> some web work, and get the details on how to best take care of them.
>>>>
>>>> HTH,
>>>>
>>>> John
>>>
>>> Thanks, good post!
>>>
>
>
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