How to 'equalize' battery?

[Roc]

I have two 4D batteries in my 2000 C34.  Always use distilled and never have to add more than a few tablespoons in each cell.  Over the winter, I usually turn the charger on every couple of weeks to keep them topped off.  Last week, I checked the voltage with a multi-tester.  I noticed 12.66 volts in one battery and 12.76 in the other.  It's been about two weeks since my last top off.  Whenever I have checked this in the past, both batteries have always been within 0.01 from each other.  I checked the water level, all ok.  I did notice that there is some caking on the plates (sulfation??).  I checked Calder's on this and there is something about an 'equalization' procedure, but it's a bit confusing (and sounds dangerous).  Has anyone tried this or should I talk to the marina and have them look at it. Any idea why one battery was 0.10 volts lower??

Thanks,
Roc-

[Ted Pounds]

Roc,

What kind of batttery chager do you have?  To do an equalization you need a charger that has that capability, such a a Statpower Truecharge.  In short equalization pumps current at 16 violts into the battery.  This helps drive sulfer back into solution (that probaly is sulfation on your plates).  It also causes vigorous gassing of the electrolyte producing hydrogen and oxygen, obviously an axplosive combo.   So you need to make sure the bateries are well ventilated and no ignition sources are present.  Of course once you are done the hydrogen rises and dissipates quickly.  You also have to carfully moniter the specific gravity of the eltrolyte during the process.  I would say it's not too dangerous if you are careful.  If your battery charger has an equaization cycle it should be discussed in the owner's manual.  Also you shouldn't have any operating equipment hooked up to the batteries during eqauization as the 16 volts could damage it (even light bulbs  can get toasted).  I plan to equalize my batteries as soon as I can set aside a few hours to do it right.

Ted

[dave davis]

Roc & Ted
I have the latest Truecharge and it has four setting for all different purposes. I also bought my battery at the American Battery factory and talked to the owner about the proper care. The 4 batteries I have are the 6 volt 220 AH type. The factory owner told me never to use the Equilizer setting on his batteries for it would distroy them for sure. He also told me not to use the lowest or first setting either( I forgot the name of this first setting). I thought I shoud pass this on for what its worth. Since he has been in the battery buis. for umteen years, I have taken his advice. I realize that we have some very knowledgeable peaple in our membership that may not agree, but now that you have other opinions, it's your turn. Good Luck... Dave

[Roc]

I have the factory Pro-Mariner charger.  I know people have had problems with these, but mine has been ok.  From what I understand there were some bad chargers installed in boats.  As I said, mine has been good and goes through the 3-stage charge procedure (I can tell from the gauge on the unit).  I'll have to check my owner's manual and see if it talks about equalization mode.  If anyone has done this with the Pro-Mariner, I would be interested to know.

Thanks,
Roc-

[Stu Jackson]

Roc

Equalization is not dangerous as long as you ventilate, ventilate, ventilate.  Make sure you are there for the process.  Never leave batteries unattended when equalizing.

The purpose of equlaizing batteries is to discharge the built up sulfite that "grows" on the cells over a period of time, and ONLY for wet cell lead acid batteries.  Gel cells should NEVER be equalized.  It's also most likely why your readings are now different: over time the batteries have built up different layers of sulfite.

Good idea to check Calder.  Another good source is the following:  http://www.amplepower.com/primer/index.html.

From this reference source and others, you will also see that it's not only the voltage of your batteries, but the specific gravity of the acid in the cells that will help you diagnose the issues.  You need an inexpensive hydrometer for this, easy to use, like a turkey baster.

Dave is right, too, if your battery manufacturer says don't, so don't.  Also, six volt batteries may well be different than standard 12 volt batteries regarding equalization.

This is not an issue of "many ideas are out there, take your pick."  Rather, the idea is for us to help you with your specific problem.  Unless your "marina" is a specialist in batteries and/or electrical systems (and most aren't), you already probably know more than they do.

Check your battery manufacturer's recommendations, figure out if your charger can do it, and do it if you need to, armed with all the technical information you can get.

[This message was edited by Stu Jackson #224 1986 "Aquavite" on May 06, 2002 at 03:47 PM.]

[This message was edited by Stu Jackson #224 1986 "Aquavite" on May 06, 2002 at 03:49 PM.]

[Roc]

Exide says that it's ok to equalize the batteries.  However, I defined that what I see is grey-ish paste over the fins and the tech guy said that's the normal stuff that they put on the plates when the batteries are manufactured.  Sulfation can be seen when the electrolyte becomes cloudy.  Mine is water clear, so he said I have no sulfation problem.  He said that equalizing the batteries will bring them both up to the same voltage.  The process is to keep the battery at 14.8 volts or higher (14.8 being the ideal voltage) and keep it there for 120 minutes.  I then called Pro Mariner.  The Flyback 20-3 charger that is installed in my boat does not have an equalization mode because Pro Mariner does not advocate doing this process in an enclosed boat (explosive gasses).  So, my question, without taking the huge 4D's off the boat, does anyone have any suggestion what type of unit could I get to bring the batteries up to 14.8 volts?

Thanks,
Roc-

[Jentine]

I am very pleased to hear that the  most major problem in your boating life is to have one battery with 1/10th of a volt less than the other.  In the scheme of things, have you noticed a perceptable difference in performance.  I suspect not!  I think you need to have less time on your hands.

[Jim Price]

Personally, being a new owner and first boat, I have enjoyed this thread of conversation as it has made me aware that I needed to follow-up on my batteries, consider the type and usage, and most importanly, determined that the charger on my boat is obsolete, will not perform these processes, doesn't do a proper job keeping the system charged adequately, is not documented anywhare, and cannot be repaired.  I am buying a new TrueCharge 40+ before I have a major (and expensive) problem.  Pay me now or mortgage me later!

[This message was edited by Jim Price, #1119, "Lady Di" on May 10, 2002 at 08:39 AM.]