[C320-list] Battery selection; Questions & Answers

[Jeff Hare]

I won't answer for Warren here, but I will say that maybe equalization is
less important on boats.

In a ground based Solar application, batteries don't move and can become
very stagnant and deposits can form on the plates leading to varying
resistances between cells.  Equalization bubbles the battery fluid to stir
it up and flake off deposits.  On a boat, they get lots of sloshing and
mixing, so it probably isn't as important.  

Equalization may do some other things as well, but I'd avoid it unless you
are having trouble.  Some say 6V golfs in series/parallel arrangement may
want each of the batteries equalized to prevent them from drifting too far
apart in cell resistances, but the thinking on all this shifts a bit
depending on who you talk with and how "...retentive" they are.  :)

But to equalize, you have to have a charger that supports that feature
specifically.  You *may* need to have good ventilation, turn off all loads,
especially halogen lights as this uses a much higher charge voltage which
can damage some equipment.  I *think* but am not sure that you may need to
loosen the battery caps, and be prepared for some cleanup with an acid
neutralizer. But, the vendor would say how this is done.  None of the stock
chargers on our boats can do this, and only some of the high output
alternator/regulator systems can do this.
 
-Jeff


-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Bruce Stanley
Sent: Monday, January 31, 2011 5:37 PM
To: C320-List at catalina320.com
Subject: Re: [C320-list] Battery selection; Questions & Answers

Warren
thanks for posting your Q&A with Exide.

Can you explain to me, how does one 'equalize batteries"?

Thanks
Bruce Stanley/C320 #1084
Sydney

I was not able to get Exide Nautilus Batteries in Australia, so I replaced
them with commercial Exide 4D Bus batteries (starting batteries).

On Tue, Feb 1, 2011 at 6:06 AM, Warren Updike <wupdike at hotmail.com> wrote:

> Following-up on Chris Burti's comments on the Exide Com-4D-P battery, I
> posed several questions to Exide via their web site and was promptly
> answered by Paul Korinek, Engineer.
>
>
>
> Q-- I'm replacing my two 4d batteries on my Catalina 320 sailboat. Here
are
> two Exide 4Ds I've found. I want to be able to discharge up to 50% for the
> most number of cycles, however, my typical discharge is about 20-40%.  My
> typical load is between 5 and 10 amps.  Total per day about 90A.  Could
you
> advise me as to which of these would best suit my needs?
>
> NG4D                    RC250   AH160 (AH/RC=0.64)
>
> COM-4D-P           RC320   AN205 (AH calculated based on 0.64RC)
>
>
>
> A-- If you can adapt to the SAE terminal post, I would suggest the
Com-4D-P
> for your cycling app given that it has approx 30% more capacity which will
> provide for a lower depth of discharge and extend life.  But if you must
> have the marine terminal, the NG-4D has this.  Both have similar chemistry
> for cycling purposes.  (WU-post adapters can be purchased to convert the
> posts to bolt type marine posts.)
>
>
>
> Q-- Do you recommend a periodic equalization of batteries under these
> conditions?
>
> A-- An equalization charge is a good practice but you have to be careful
of
> too much of a good thing.  Excessive equalization / overcharging will
> dramatically shorten the product life due to grid corrosion and paste
> shedding.
>
> The equalization should not exceed 6hrs and water levels should be
> monitored
> before and after.  I would not equalize the battery more than once per
> month
> during use.  If the battery is performing OK and the charged voltage is >
> 12.8V when the acid levels are good, you don't need to equalize.  I would
> equalize after you add water to mix the acid to avoid stratification which
> can occur.  (WU-Others recommend that you monitor an equalization process
> with a hygrometer to avoid over charging.)
>
>
>
> Q-- Do you recommend several initial deep discharge/recharge cycles as a
> break-in before placing in-service?
>
> A-- Initial cycling is not a bad idea but not absolutely necessary for
> Exide
> batteries.  An initial equalization charge is the most important thing to
> bring the state of charge up to the 95%+ range.  Other manufactures
> design/mfg their product such that it does require 10-30 cycles to reach
> the
> rated capacity.  But this is not the situation with these Exide products.
>
>
>
> I'm going with the COM-4D-P this spring.
>
>
>
> Warren & Pattie Updike
>
> 1994 C320 #62 "Warr de Mar"
>
>
>
>