Battery choice - unique circumstances

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.

Pat

Well-known member
Joined
Mar 17, 2005
Posts
1,234
Location
Payson AZ
I have to replace my two 12v coach batteries.  Again.  I am going to get the maintenance free ones because I can't see to add water to the back battery. I tried the battery watering system.  I think the shut off valves don't work.  Acid has slopped all over.  I understand the Optima maintenance free ones are more expensive than the regular Group 27s that I have now, and at least one person said they aren't as powerful.  Since I boondock approximately two days per year, this should not be a problem.  I don't even use the furnace, which is the main 12v draw in my mh.  I've killed too many pairs of batteries.  If these die an early death, then I'll have a better indication that something in my coach is reducing normal battery life.  I have a new converter, so at least these won't be subjected to the old defective one. 

I believe that 4 years and at least as many pairs of batteries has proved that I have tried the maintenance route.  I've been talked into sticking with the batteries that need watering a couple times now.  Time to make a change. 

--pat
 

John From Detroit

Well-known member
Joined
Apr 12, 2005
Posts
24,786
Location
Davison Michigan
One thing you should consider when changing battery types is your charger system.  My coach came with a Progressive Dynamics Intella-Charger with Charge Wizard... Near as I can tell from my research this is absolutly the best charger for the batteries that were factory installed (Interstate Work-A-Holic U220 Golf Cart batteries, flooded wet cells)

However for Optima or AGM or Gel cels,,, not so good (not good at all from the research I did)

My alternative battery charger happens to be my inverter, a Xantrex Prosine 2.0,  As it happens I do not believe (After all the readings) that it is the best charger for the Work-A-Holic flooded wet cells, but it has a bunch of settings  and if properly set it is on the "Best List" for other types of batteries including Gel, AGM and Optima

Now... I do not know if they do this but if I was Progressive Dynamics I'd make multiple charge wizards (they are fairly cheap and easily to swap out) which would customize the Intell-a-charger for each battery type.

(Does anyone know if they make a Charge Wizard programmed for AGM?)

But this is a consideration
 

Gary RV_Wizard

Site Team
Joined
Feb 2, 2005
Posts
73,522
Location
At our Silver Springs FL home
Pat,
Most likely you have fixed the battery-life problem with a new converter. Even if you didn't get one of the best types (such as the Progressive Dynamics one that John mentioned) it should be far superior to what you had before. Clearly it was overcharging if your batteries continually ran dry.

I'm not impressed with the Optima specs - their "Yellowtop" deep cycle is a "dual purpose"  deep cycle & starting battery with relatively low capacity at a high price.  In my opinion, dual purpose batteries are a waste for an RV house battery, since it sacrifices amp-hour capacity to provide high energy for engines starting, something you never will do with it.  But deep cycle only, maintenance free batteries are hard to find in stores. Now that AGM batteries are becoming popular, you may be able to find an AGM deep cycle somewhere. An AGM battery is sealed (like the Optima) and totally maintenance free. Price should be the same or less than an Optima, but local pricing can vary a lot.  I've been running a Lifeline deep cycle on my Iota converter/charger for a couple years now with no observable ill effects. Maybe it won't last as long as it might have with a proper "AGM charger", but it certainly hasn't died of abuse either.

But for your limited use, you may not care all that much about deep cycle capacity. A regular gel type, maintenance free battery of the sort usually labeled "marine deep cycle" or "marine starting/deep cycle" would be a lot less money than a Lifeline or Optima and would certainly provide what little 12V power you use when boondocking 2 days/year.  I would expect the life to be 2-3 years with a typical RV converter/charger.  An Optima or AGM would probably last 3-6 years.
 

Pat

Well-known member
Joined
Mar 17, 2005
Posts
1,234
Location
Payson AZ
I need to print this thread and take it to the battery place tomorrow.

The battery guy who is recommended on N. Country Club here in Mesa has a couple AGMs I thought I'd get.? I decided to take the mh in to have the cables checked as well, rather than doing it ourselves.?

Based on the questions raised here by Gary and JID, I called Iota.? I have the DLS 45. Their tech said normally people have to take off the IQ Smart Charger for the AGMs.? I get the impression there are different "smart chargers" for different batteries, and the battery shop might have something for the AGMs.? He said the Iota DLS 45 will be fine, though.? He said to tell the battery shop that the IQ Smart Charger attachment does the following:

Float 13.6
Bulk/turbo 14.8
Absorption/soak voltage 14.2

They might have an attachment to the charger's RJ11 jack that will manage the AGMs properly.? Does anybody know of one?

I apologize if this question was already answered in previous replies.? I have printed and have to study them a bit more to understand all of the terms.

Thanks for the info

--pat
 

Gary RV_Wizard

Site Team
Joined
Feb 2, 2005
Posts
73,522
Location
At our Silver Springs FL home
I have a DLS 90 with the IQ Smart Charger and it does indeed float at 13.6. I have not been able to find any alternate Smart modules for different battery types.

I've never seen any description of what happens if the recommended float voltage is excceded on an AGM. Lifeline recommends 13.4V for theirs but some other brands are higher, so I don't know how critical it really is. As I said, I have not had any bad experience yet with mine. And I'm breaking all the "rules" of traditional wisdom, since I have dual battery banks, one with Flooded-type 6V golf cart batteries and the other with 12V AGM. Both are charged from the same 90A charger, at the same rate in each of the three charging stages. The AGM bank is 2 years newer than the golf carts too.  I should probably expect an explosion any day now!  ;D ;D Meanwhile, though, I'm a happy camper.
 

Pat

Well-known member
Joined
Mar 17, 2005
Posts
1,234
Location
Payson AZ
Gary:  Got my AGM batteries today.  Two 12v.  The installer phoned somebody and read those specs.  Whoever was on the phone said those are fine for the new batteries, so I left the IQ Smart Charger attached. 

Sure have a nice clean battery drawer now. 

--pat
 

Pat

Well-known member
Joined
Mar 17, 2005
Posts
1,234
Location
Payson AZ
Gary:  I just hope the guy on the phone knew what he was talking about.  The fellow in front of me in the store kept thinking the specs were for the charger and not the IQ attachment. 

My batteries register about 12.9 right now.  I haven't plugged in and started the charger yet, beyond running the generator for a half hour this afternoon.  I suppose I should charge them up before I leave.

--pat
 

Gary RV_Wizard

Site Team
Joined
Feb 2, 2005
Posts
73,522
Location
At our Silver Springs FL home
The fellow in front of me in the store kept thinking the specs were for the charger and not the IQ attachment. 

Those are synonomous, Pat. Once  the IQ is attached, it takes over control of the charger and changes the voltages and duration of charging stages from the default to "smart" mode.  The specs are different with the IQ attached than without one.
 

Pat

Well-known member
Joined
Mar 17, 2005
Posts
1,234
Location
Payson AZ
Gary:  I do like having the smart charger attached, so I'm glad the settings work.  The new batteries are remaining cool.  The couple times I checked, the voltage indicator stayed at about 13.6 today.  I had plugged in toshore power to let the charger do its job on the new batteries.  About the only draw was alarm indicators.  They started the day at about 12.9.  Can't get over how much cleaner the battery drawer looks without the mess. 

I was using that Qwik Fill watering system on the old batteries, and when I removed it yesterday, I could see that some of the cells were overfilled.  The shutoff valves failed from about the third fill.  It was quite a mess.

New tires, new batteries, new (working) charger, fixed toilet.  This summer should be carefree.  With all the maintenance issues, I was beginning to refer to last summer as the summer from hell. 

--pat
 

Ned

Moderator Emeritus
Joined
Feb 1, 2005
Posts
25,107
Location
USA
AGM batteries should be kept at a float voltage of 13.1-13.3 V according to Lifeline.  This is about .2 V lower than the float voltage for flooded cell batteries.  Using the higher float voltage will shorten the life of AGM batteries due to the slight overcharging that results.  My previous Link 1000 didn't have a setting for AGM and as a result I had to replace all of the batteries after 4 years when I should have gotten 5+ years of use.
 

Pat

Well-known member
Joined
Mar 17, 2005
Posts
1,234
Location
Payson AZ
Today the voltage indicator showed over 14 while the yellow "charging" light was on.  Now the green light by "charged" is on, and the voltage indicator is back down to 13.6.  Looks like the IQ is doing its job according to specs. 

If there's an IQ adapter that will maintain the 13.1, I'll be happy to order it.  I don't want to toss the new charger, not to mention what I just paid somebody to attach it properly. 

--pat
 

Ned

Moderator Emeritus
Joined
Feb 1, 2005
Posts
25,107
Location
USA
You can ask if they have an IQ for AGM batteries, or if the IQ is adjustable for battery type.  I know nothing about the IQ device so this is conjecture.
 
Top Bottom