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New Coach Batteries

Bionic_Man
Explorer
Explorer
It is about time to change batteries in the coach. I have the standard two 12-volt system, which I think I will stay with. But I am considering going to AGM batteries.

When we camp, we usually have electricity. At least until fall when we put the boat away, and then we switch to more federal lands in the mountains without electricity. The RV is stored at home, and is left plugged in so that we don't have to load/unload the fridge every trip. I do my best to add water to the batteries over the course of the year, but sometimes I forget.

Would there be an advantage to going to AGM batteries in the above scenario?
2012 RAM 3500 Laramie Longhorn DRW CC 4x4 Max Tow, Cummins HO, 60 gallon RDS aux fuel tank, Reese 18k Elite hitch
2003 Dodge Ram 3500 QC SB 4x4 Cummins HO NV5600 with Smarty JR, Jacobs EB (sold)
2002 Gulf Stream Sea Hawk 29FRB with Honda EV6010
32 REPLIES 32

MEXICOWANDERER
Explorer
Explorer
486 years old and it still lives!!!!!

Igor hit it with another jolt!



SEE!!

SEE!!!

Ten steps!

At first, it took 15,000 steps

But it's still LiVVVVVES

Turn up the dial igor

ccchuck
Explorer
Explorer
BFL13 wrote:
ccchuck wrote:
I am considering this battery for my "house" battery on a 2006 Grayhawk - would it work with my original charger system?

https://www.samsclub.com/p/duracell-agm-deep-cycle-marine-and-rv-battery-group-size-31dtmagm/prod3590232?xid=plp_product_1_2


Which converter does it have? Some earlier ones had the Iota with no jack for the IQ4. That would be no good. Then they went to PDs ISTR. That would be good but only with the Charge Wizard for it.


I will try and determine what converter I have - thanks
RVing since '74..

pianotuna
Nomad III
Nomad III

https://www.samsclub.com/p/duracell-agm-deep-cycle-marine-and-rv-battery-group-size-31dtmagm/prod359...
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

BFL13
Explorer II
Explorer II
ccchuck wrote:
I am considering this battery for my "house" battery on a 2006 Grayhawk - would it work with my original charger system?

https://www.samsclub.com/p/duracell-agm-deep-cycle-marine-and-rv-battery-group-size-31dtmagm/prod3590232?xid=plp_product_1_2


Which converter does it have? Some earlier ones had the Iota with no jack for the IQ4. That would be no good. Then they went to PDs ISTR. That would be good but only with the Charge Wizard for it.
1. 1991 Oakland 28DB Class C
on Ford E350-460-7.5 Gas EFI
Photo in Profile
2. 1991 Bighorn 9.5ft Truck Camper on 2003 Chev 2500HD 6.0 Gas
See Profile for Electronic set-ups for 1. and 2.

ccchuck
Explorer
Explorer
I am considering this battery for my "house" battery on a 2006 Grayhawk - would it work with my original charger system?

https://www.samsclub.com/p/duracell-agm-deep-cycle-marine-and-rv-battery-group-size-31dtmagm/prod3590232?xid=plp_product_1_2
RVing since '74..

MEXICOWANDERER
Explorer
Explorer
The definition of careful




I've not tried this with Bird's Nest Soup, brand batteries. Or Telecomm. But left on for days, in 100-degree weather, the Lifeline gained around 4.5 degrees F.

Higher than recommended float voltage over time, lots of time, accelerates plate erosion so NO it is not good for the longevity of ANY battery. Flooded, AGM, Gel, Alkaline, Lithium.

But this ain't like Baked Alaska, where a slight error ruins the dessert. And 14.4 volts will kill a flooded battery much faster than an AGM. Three or four extra unneeded hours at 14.4 volts for a thousand times may render an AGM devoid of .010" positive plate material. The battery still would have an infintely longer usable lifespan than it will living in an underchaged state.

Let's say we DOLBLE the plate thickness

Ring any bells?

The manufacturer who refuse to reveal plate thickness does it for a reason and that reason isn't pretty.

"And how many karats is the gold in this solid gold 5000 dollar watch?"

"Enough"

But then I squeeze pesos so tight I make the Aztec fart...

BFL13
Explorer II
Explorer II
Mex- "It takes an intense amount of ignorance to harm an AGM battery. And the first correction is

14.4 volts static will not, cannot, won't and does not cause gassing"

I was just sayin, that mine heat up with rising amps after amps bottom out when they are full and I leave them on at 14.4. (as confirmed by LY) That can't be good for them, even though they are not (yet?)gassing.

Meanwhile, if you do that with Wets, they do gas but not heat up like that, so you are ok as long as you get there before the plates are exposed. Just add water.

To me, that means you have to be more careful with the AGMs
1. 1991 Oakland 28DB Class C
on Ford E350-460-7.5 Gas EFI
Photo in Profile
2. 1991 Bighorn 9.5ft Truck Camper on 2003 Chev 2500HD 6.0 Gas
See Profile for Electronic set-ups for 1. and 2.

pianotuna
Nomad III
Nomad III
landyacht318,

Thanks for the reply. May your batteries never fail!
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

landyacht318
Explorer
Explorer
pianotuna wrote:
landyacht318 does your AGM behave in the same manner as BFl13's?


Yes and No.

When newer, below about ~750 deep cycles or so, amps would simply keep tapering to 0.0X if left at 14.7v indefinitely.

From 750 to ~1000 deep cycles it would not taper much if any below 0.3v at 14.4 to 14.7v, but remain steady(90Ah capacity). A high amp recharge from a well depleted state would return its ability to taper to 0.2 amps before rising, but many low and slow recharge cycles and it would stop tapering above 0.4 amps and plateau or slowly start rising.

Now in the 1200 deep cycle range, and approaching 6 years of age in November, the amps do not taper below 2.1 amps and once they bottom out they start rising, and so does battery temperature at that point.

High amp recharges at this point, from a well depleted state, do not change this minimum amperage at absorption voltage, but do affect voltage retention during subsequent overnight discharge cycles.

But what i find surprising is the voltage retention during overnight usage. For the Ah removed, the voltage retained under load has remained impressive. It is still better than any previous flooded group 27 or marine battery even when they were new, at least until ~55 to 60Ah from full. I can pull 55Ah from it at upto 2x the 20 hr rate load, and will still read 12.0+ volts under a 5 amp load and rebound to 12.15 range with most of the loads removed.

It can still accept 65 amps for more than 15 minutes before voltage rises to 14.7v when discharged below 50%.

if it were not for the voltage it falls to when engine starting, and the amps never being able to taper to 0.5% of capacity before beginning to rise again, I would proclaim the battery to be 'still going strong' but it has to be approaching the end, I assume.


I bought a UB12180 AGm battery Last December for when Mine can no longer start my engine on its own.

This Ub12180 battery was difficult to get to taper to 0.5% of capacity when new and rarely now either, though I do not cycle it often, mostly just hold it at 14.7v for a few hours each week on its own ammeter unless I use it to jumpstart someone else, then I recharge it immediately.

Once amperage at absorption voltage bottoms out, there, or above there, amperage instantly starts rising along with temperature and if I do not reduce voltage or remove charger, I assume both amperage and temperature would keep rising.

While I can't argue with plate thickness being an obvious attribute for a deep cycle battery, I also cant argue that this Thin Plate Pure Lead Northstar AGM battery has far exceeded my expectations as far as deep cycles accumulated and dual purpose ability. It is still able to easily meet my needs, as long as I ensure the regular true full recharge, and it can still easily start my engine 55Ah from full in mild/warm ambient temperatures.

When it does need replacement, I'll go well out of my way to acquire another, perhaps stepping up to a G31 instead of a 27, and pay top $ for it, even though I could have a lifeline g31-XT delivered to me fresh from West Covina, for similar price.

pianotuna
Nomad III
Nomad III
Hi Mex,

I do want to learn. But perhaps I'm a slow learner, or my background is not similar to yours.

On the other hand, few folks here would know what a hemidemisemiquaver is.

Thanks for the information that a Telecom design is nothing like a car battery. I have, in the past, compared them to flooded deep cycle batteries. Thanks for correcting that bit of misinterpretation on my part. I know they are a weird format. I do follow the specific makers recommendations for charging as well as I am able to.

Was I correct in my guess that the Lifeline batteries have thicker plates? If not, would you grace us with the answer please?
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

MEXICOWANDERER
Explorer
Explorer
It takes an intense amount of ignorance to harm an AGM battery. And the first correction is

14.4 volts static will not, cannot, won't and does not cause gassing. You know how I know this without question? instead of armchair dart throwing I actually created an environment with my own two hands with a genuine AGM battery not some abortion telephone morphidite but a real BCI battery in 100-degree weather, set the Borg on 14.4 volts and left it there for 5 days. Afterward the battery measured 104.4F

Let me count the ways...

  • At 80F ambient, it takes voltage in excess of SEVENTEEN to Maybe crack the vents for a second or two to relieve pressure. Have you ever done this?
  • Now tell me, is SEVENTEEN anywhere near fourteen point four volts?
  • Is a hundred degree day anywhere close to rational for doing a reclamation on sn an AGM battery?
  • Leave your dog or your children in a car overnight lately? How the hell can anyone start charging a battery and just walk away? Does the thought of a timer shutoff ring any bells out there?
  • Have any of you baked a cake or roasted a turkey before. Temperature and Voltage are amplitudes and time is time? Well, lessee, three hours at 375F is the same as nine hours at 215 or seventeen minutes at 1,700F right?


Some of the answers border on the ludicrous. If you want to LEARN ask questions. Don't assume to create a qualitative or quantitive answer out of thin air. The reality in the form of hard facts jump up and will screw up even the best efforts of fiction. Like recombinant cell caps. Like pure virgin lead paste.

It is foolish to compare an automotive battery to a telecom battery. They exhibit different traits in different environments both chemical and electrical. To do so is like trying to compare a heavy-duty truck gasoline engine to a diesel.

A moderate overcharge will dry a flooded battery to dust. The same -percentage overcharge- will erode AGM plates without venting one molecule into the atmosphere. Are we on the same page here? Again and again, amplitude and time enter the picture here.

And for chrissakes, please get it clear that a battery charger is not the same as a converter. Apparently, some converters can be reprogrammed with a setting t become a constant voltage device. These critters are rare indeed and REGARDLESS only a fool would entertain the idea of time has no bearing on a constant voltage condition.

A stupid 14.4 volts with a stupider timer is all that is needed to bring an AGM battery to 14.4 volts. Sixty bucks for a Meanwell or Megawatt and a million cycle durable wind up timer. No complex voltage and time formulas like with a wet battery. But then when I read complaints on this forum that a person needs to rise off their dead *** a few times to discover WHEN a flooded battery starts to bubble and thereafter use the voltage and amperage displayed on their wall meter as a valid reference from then on I gave up. Suffer excessive battery problems but don't take personal malfeasance public and try to blame it on bad batteries.

And LY, this subject has as much to do about politics as margarine has to do with antifreeze. If an individual wants nothing to do with their batteries then suffer silently.

pianotuna
Nomad III
Nomad III
landyacht318 does your AGM behave in the same manner as BFl13's?
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

BFL13
Explorer II
Explorer II
PT---"It is my understanding that 'normal' AGM cells are a "starved acid" design. So once all the electrolyte has been moved to the plates, charging more won't cause the battery to gas."

My AGMs get down to about 0.5a/100AH but if I don't get back to them till later, the amps will be higher and climbing. The batts feel hotter, confirmed by IR gun temps. Must yank the charger if that happens!

So now I always try to be there at the low amps stage so I can drop the voltage.

I don't know what "kind" of AGMs I have. The ones this happened with are same as these, but branded "Stark".

http://www.bestconverter.com/UB121000-100-AH-Deep-Cycle-_p_293.html#.XWm2vknsZpw
1. 1991 Oakland 28DB Class C
on Ford E350-460-7.5 Gas EFI
Photo in Profile
2. 1991 Bighorn 9.5ft Truck Camper on 2003 Chev 2500HD 6.0 Gas
See Profile for Electronic set-ups for 1. and 2.

landyacht318
Explorer
Explorer
How soon before this thread too, devolves into politics?

5.4.3.2.1.....