[C320-list] Battery Charging

[crashley at gte.net]

Warren,

The battery literature I've found says that the AGM and flooded marine 
batteries use the same charge voltages since it's the same battery 
chemistry, the difference being that the electrolyte is contained in a glass 
mat as opposed to liquid form. And they are truly sealed never requiring 
water to be added (which is maybe the main reason I went with them). As you 
say, it also mentions that the AGMs are more sensitive to overcharge and 
temperature compensation is recommended. Apparently the GEL cells are a 
whole different animal.

Some links:

http://www.eastpenn-deka.com/default.aspx?pageid=468

http://www.vonwentzel.net/Battery/

CRA
Rosebud #882


----- Original Message ----- 
From: "Warren Updike" <wupdike at hotmail.com>
To: <C320-List at Catalina320.com>
Sent: Tuesday, February 12, 2008 4:26 PM
Subject: Re: [C320-list] Battery Charging


>I presume y'all new owners of AGM batteries know that the charging voltages 
>for AGM are different than for Gel or AGM.  If your charger cannot be set 
>for specific battery types, you might not want to leave your new AGMs on 
>charge all the time.  They may seem like small differences; but, 
>apparently, it makes a difference.
>
>                                Absorbtion    Float
> Flooded (wet cell)    14.2 to 14.5V 13.2 to 13.5V
> AGM                      14.4 to 15.0V  13.2 to 13.8V
> Gell Cell                  14.0 to 14.2V 13.5 to 13.8V
> Source: www.batterystuff.com
>
> I'm not an expert here, just aware of stuff.  Check with your battery 
> manufacturer.  Or, perhaps one of our "experts" can check-in on this.
>
> Warren & Pattie Updike
> C320, #62, 1994, "Warr De Mar"
> Frog Mortar Creek, Middle River
> Chesapeake Bay
>
> ----- Original Message ----- 
> From: <crashley at gte.net>
> To: <C320-List at Catalina320.com>
> Sent: Tuesday, February 12, 2008 1:21 AM
> Subject: Re: [C320-list] Battery Charging
>
>
>> Doug,
>>
>> That seems to be the general consensus. Up to now I have always left the 
>> charger on but I had a cell go bad (shorted) in one of my two 4D flooded 
>> batteries a couple of months ago. They were only 5+ years old, but the 
>> boat was used and I'm not sure how deeply or frequently the previous 
>> owner may have disharged them. I replaced them with two 4D AGMs and 
>> certainly don't want to abuse them.
>>
>> Thanks,
>> CRA
>> Rosebud #882
>>
>>
>> ----- Original Message ----- 
>> From: "Doug Stieber" <djstieber at gmail.com>
>> To: <C320-List at catalina320.com>
>> Sent: Monday, February 11, 2008 6:59 PM
>> Subject: Re: [C320-list] Battery Charging
>>
>>
>>> Batteries last best if kept at full charge.  If your battery charger is
>>> operating properly, it will cut out when the batteries are fully charged 
>>> and
>>> only cut back in when they need to be charged.  My advice is to keep the
>>> charger plugged in all the time.  By the way I replace my batteries 
>>> after 7
>>> years even though they still had life in them.
>>>
>>> Doug Stieber, Second Chance #406
>>>
>>> On Feb 11, 2008 5:06 AM, <crashley at gte.net> wrote:
>>>
>>>> I've heard that one should not keep boat batteries on charge for 
>>>> extended
>>>> periods. That is, when docked in my slip (which is most of the time), 
>>>> should
>>>> I leave the charger on continuously or leave it off and only charge 
>>>> once a
>>>> month (or so)? The charger is a 3 step type which ends up in "float" 
>>>> mode at
>>>> about 13.5 volts. Also, the charge is a Pro Mariner 1230 which seems to
>>>> have a bad reputation. Any advice?
>>>>
>>>> Rosebud
>>>> #882
>>>>
>>>
>>
>>
>>
>>
>
>