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Equalizing AGM batteries

April 05, 2017, 10:52:10 am

Do you equaliz your AGM batteries every now and then. Specifically East Penn ( O'Rllies, MK) brand?

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Re: Equalizing AGM batteries

Reply #1 – April 05, 2017, 11:51:35 am

Go to your manufacture's web site and they will have all the voltages, settings.  After purchasing ours, I went to their site where they specifically said NO to equalization on our AGM.

Pierce

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Re: Equalizing AGM batteries

Reply #2 – April 05, 2017, 11:56:39 am

Some manufacturers suggest yes, some no.  If the website isn't helpful, call the company, and ask them for their literature.  For our AGMs, the literature/settings were different based on whether the battery was used in renewable energy (solar) or not, so that's probably worth mentioning.

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Reply #3 – April 05, 2017, 11:59:05 am

Bruce if you go to the East Pen site you will find the info as I was looking at it a week or so ago and  I seem to remember they give the voltages and  info on what to do for equalizing.
My Lifeline (concorde) batteries state up to 15.5 v for a limited time and my solar controller is programmed fot 14.8 for 60 mins every 28 days. I fell the batteries are still really good and now are 6 yrs old.. Concorde actually have a little manual that comes with every battery giving recommended settings and when I bought them thru AMSolar they too recommended it.
JohnH

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Re: Equalizing AGM batteries

Reply #4 – April 05, 2017, 12:26:27 pm

My guru buddy mentioned equalizing AGM's recently and the lifelines in particular.

He had a warranty issue with a lifeline Agm installation and returned them.

Their comment to him was that needed and had not been equalized.

His response is that they are sealed units.  No vents....

Maybe someone else can contact their manufacturer and ask about this.

Part of his reason to only use gels as they do not require equalization and have a longer cycle life span.

All uni's from Foretravel came with gels.

Damaged many sealed units long ago from overcharging and equalizing Agm batteries.

Bulging cases were regularly encountered.  Majority 25+ years ago.

Not as smart of chargers and poor equalization?

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Reply #5 – April 05, 2017, 12:34:45 pm

Equalizing is a controlled OVERCHARGE.
It effectively does a fast desulfation.
Not recommended for sealed batteries because it produces high volumes of gas (hydrogen and oxygen), which can pressurize a sealed battery and cause permanent damage.
A "Desulfator" will safely desulfate but requires a day per amphour, so seven months for an 8D sized battery.
I have a desulfator on each battery, purchased on eBay for about $25.00.
A fully charged and resting wet cell battery will have a voltage of circa 12.7 volts.
A fully charged and resting AGM battery will have a voltage of circa 12.8 volts.
A fully charged, desulfated and resting AGM battery will have a voltage of circa 12.95 volts.

I am not positive that desulfation increase the service life of an AGM battery for deep cycle?
My desulfated Lifeline AGM batteries provided 5 years of service ( 1200 cycles).
However, my Lifeline Gel battery from 2003, provided 12 years of service (2500 cycles), was in better condition then the 5 year old AGMs, and is still in light duty service today (still provides circa 50 amphours).

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Re: Equalizing AGM batteries

Reply #6 – April 05, 2017, 12:47:45 pm

Discharging a battery is a sulphation chemical process.
Charging a battery is a desulphation chemical process.
I do not agree with Caflashbob that Gel batteries do not need desulphation, because discharging/charging a Gel battery still involves sulphating/desulphating.

Unfortunating, charging does not completely desulphate a battery, so the advantage of Equalizing or Desulphating, is that it completes the desulphation (i.e. charging).

While Equalizing or Desulphating definitely extends the life of a flooded battery and is required - it is not clear to me that it extends the life of AGM or Gel batteries.

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Reply #7 – April 05, 2017, 07:44:09 pm

So my buddy was in error removing my  electronic desulphating equipement from my gels?

I though mk gels had calcium in them?  Not that makes a difference. 

Your service life difference matches mk's web sites projected cycle life's

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Reply #8 – April 06, 2017, 10:16:46 am

Looked on East Penns web site (actually MK) it mentioned equilizing with a brief description but that's it. So I e-mailed them, got a reply right back. They are mailing the information for some reason they don't e-mail it. So we'll see what we get.

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Reply #9 – April 06, 2017, 10:29:24 am

This is from Lifelines website.

Can I equalize AGM batteries? - Lifeline Batteries

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Reply #10 – April 06, 2017, 12:38:40 pm

Caflashbob posted in Reply#7:
"So my buddy was in error removing my  electronic desulphating equipement from my gels?"
Yes, I believe that your statement is true, if you prefer to have Gel batteries that last a long time! 
A "desulphator" works by applying an intermittent 50 volt, 6 amp spike for 1/10000 second. This spike happens a thousand times a second and can safely be applied constantly.
Equalizing works by applying a higher then normal charge voltage while limiting the amperage. The danger with equalizing is heat and fast out gassing.
Equalizing has been done for decades and manufacturers know about it and recommend it.
Desulphating was discovered by an unknown guy who was experimenting with restoring failed batteries 15 years ago. The first desulphator I used 13 years ago, was built from components. They are commercially available now but battery manufacturers are not endorsing them yet - this I do not understand.

Caflashbob posted in Reply#7:
"I though mk gels had calcium in them?  Not that makes a difference." 
I am not sure what calcium does but it may make a difference. Battery manufacturers are experimenting with chemical additives in an attempt to make better batteries than their competitors. However, battery manufacturers make money if their batteries last three years, than if their batteries last five years, or ten years. I believe that it is possible that AGM battery manufacturers could make batteries which last 20 years, however, it would not be financially prudent for them to do that.

Caflashbob posted in Reply#7:
"Your service life difference matches mk's web sites projected cycle life's."
Yes, I have noticed that (Gel batteries will cycle 2500 times while AGM batteries will cycle 1200 times).
When I bought Lifeline AGM batteries in 2010, the salesman told me that Lifeline had modified their AGM batteries so that they cycle as many times as a Gel battery.

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Re: Equalizing AGM batteries

Reply #11 – April 06, 2017, 12:47:43 pm

The mk engineer mentioned to me that east penn had changed two major things in their gels that they and he thought could double the already excellent cycle life.

Different plate separators and being able to pre charge the plates in production before installing them in the cases  allows them to test and eliminate bad plates before installation.

He mentioned he had a lot of Foretravel owners with 12-13 year old gels talk to him over the years so the newer design could be interesting.

Will reinstall my  units as I cannot see any possible harm from them 

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