What Size and type of Battery to Use?

[Buck Rabbit]

I have a 1990 Excella 29' that I just purchased in November. It had been setting on shore power, without use, for 2+ years. Both batteries are shot. One is an Interstate Deep Cycle batter. The other is a regular car battery. I have learned in the past to not trust the previous owner of anything on if they did things right. My question is, What type of batteries should I use and what size should I get? In that I mean what specs should I be looking for? I have a friend that is an Interstate Battery dealer and he can get me a fairly good deal if that is the way to go.

On a separate note, the charging system sends out a constant ringing, wine, hum that will drive a def man crazy when it is quiet outside. What is the best replacement option here?

Thank you, to anyone who can help.

[Caffeinated]

My '15 came with two group 24 interstate wet cell deep cycle batteries. That is the default from the factory, I think because it's what Thor can get at the cheapest price.

There seem to be almost limitless systems and batteries to chose from. It would probably help if we knew how you want to use the trailer. Ie, do you intend to boondocks extensively, or mostly have full hookups, or 50/50?

Mike

[Caffeinated]

There seem to be many choices for both batteries and charging sysrems. It would be helpful to know how you intend to use the trailer. Ie, will you be boon docking a lot, or mostly full hookups? Or some of both?

Mike

[Scorge-ION]

1. Both batteries must be the same.
2. Get VRLA (Valve Regulated Lead Acid) deep discharge batteries. Select by weight: heavier batteries have more lead in them, giving longer service.
3. Use the largest size that will fit into your compartment. That’s usually Group 27 or Group 31.

[Buck Rabbit]

we will be mostly in campgrounds on full hookup. Little off the grid for now. Batteries fill the compartments and look to be a typical car battery size.

[Caffeinated]

Measure your batteries. Length, width, and height. Then you can check out specs to see which batteries will fit your battery holder. Batteries are like everything else, you pay for what you get. I had to replace my interstates after a year. Interstates have a one year warranty. I went with Trojans, same size and amp hours but a three year warranty. The Trojans cost more that the Interstates. Some people upgrade to AGM batteries, so they don't have to worry about adding water to the cells, and I think they get more amp hours. But more money. Some go to lithium batteries and solar chargers. More money still. Check out the battery threads in the repair section of the forum.

Mike

Mike

[m.hony]

Seems like my trailer came with 2 Group 27 Interstate batteries.
When the original batteries died I replaced them with AGM batteries.
I'm thinking Group is just the actual size of the casing.

[Jacob D]

Originally Posted by Buck Rabbit

I have a 1990 Excella 29' that I just purchased in November. It had been setting on shore power, without use, for 2+ years. Both batteries are shot. One is an Interstate Deep Cycle batter. The other is a regular car battery. I have learned in the past to not trust the previous owner of anything on if they did things right. My question is, What type of batteries should I use and what size should I get? In that I mean what specs should I be looking for? I have a friend that is an Interstate Battery dealer and he can get me a fairly good deal if that is the way to go.

On a separate note, the charging system sends out a constant ringing, wine, hum that will drive a def man crazy when it is quiet outside. What is the best replacement option here?

Thank you, to anyone who can help.

In our '67 we replaced the original UniVolt with an Intellipower 9100 solid state converter which is completely silent and does not fry the battery. We also switched to an Optima gel battery which is lighter weight than the average wet cell and it has outlasted all the wet batteries we have bought by several years. All that said, the advice of the other posters all sound good. We plan to replace our single battery with two Optimas or equivalent when this one goes to give us more power when boondocking.

[Rgentum]

Upon acquiring our 2016 AS 27, I replaced the two Group 24 lead-acids with two Group 27 AGMs, at approx. $200 each. I've had boats for decades & learned long ago that for me, paying extra for AGMs over lead-acids was worth it: no upkeep requirements, totally sealed, approx. 2X lifetime.

[planosteve]

I'm with Rgentum. I use the Optima Blue top AGM batteries. Much longer life than the factory-supplied Interstates.

[franklyfrank]

Originally Posted by planosteve

I'm with Rgentum. I use the Optima Blue top AGM batteries. Much longer life than the factory-supplied Interstates.

Do you guys keep a trickle charger going on the AGM while in storage or do you disconnect them ? Also these are maintenance free correct.

[m.hony]

Sometimes I leave it plugged in to the house for weeks or months at a time.
Right now it is just sitting out there with the use/store switch in the store position.
We use the trailer too often to worry about disconnecting or removing the batteries.

[Jim Arnold]

Newbie here!! My wife and I are going to Phoenix first of April, for our first long trip!! Are wanting to use route 66 as much as possible. Leaving from Indianapolis! Opinions are very much appreciated!!

[planosteve]

Originally Posted by franklyfrank

Do you guys keep a trickle charger going on the AGM while in storage or do you disconnect them ? Also these are maintenance free correct.

I just disconnect. I considered installing a cutoff switch, but the ones I saw on amazon looked like they would not fit inside the box. So I simply disconnect one of the terminals. BTW, disconnecting or trickle charging is very important. I recently had to replace my Optimas because I neglected to disconnect before storing. 3 months later, the batteries were totally drained and could not be recharged (I left one of the interior lights on). Fortunately for me, they were still under the full 24-mo Optima replacement warranty.

And yes, they are sealed and totally maintenance free.

BTW, even if you press the "storage" button, the system will still be taking power from the battery unless you disconnect, because CO monitor continues to operate.

[Scorge-ION]

Originally Posted by franklyfrank

Do you guys keep a trickle charger going on the AGM while in storage or do you disconnect them ? Also these are maintenance free correct.

Always keep a 3-stage charger on the battery, Old fashioned "trickle chargers" are horrible for killing batteries. Either (1) they're too low voltage to keep the battery voltage at 13.7Vdc (float voltage) or (2) they're too high voltage, causing loss of water (which you can't replace because the battery is sealed) by electrolysis.
The marketer who invented the term, "maintenance free" should be dragged through the cactus naked with bamboo shoots under his fingernails and wasps stinging him!
An AGM-VRLA battery self-discharges just the same as a flooded battery.
An AGM-VRLA battery loses water by overcharging just the same as a flooded battery.
AGM-VRLA has two things going for it. AGM:Absorbed Glass Mat uses a fiberglass sponge to hold the sulfuric acid. VRLA: Valve Regulated Lead Acid has tiny one-way pressure valves to release the pressure of hydrogen and oxygen produced via electrolysis and has a small catalyst to (we hope) convert the hydrogen and oxygen back into water.
AGM: means never having to worry about it leaking because the acid stays in the fiberglass mat. 1. AGM has less battery acid than a flooded cell. 2. The battery acid isn't as mobile in the mat as it would be in a flooded cell. Result: AGM has slightly less storage capacity (amp*hours), can supply less peak current (amps), can't absorb charge as quickly, and is slightly less efficient (due to increased electrical resistance from pushing acid ions through the mat rather than allowing them to circulate freely in a liquid.
Safety and convenience trumps all those negatives.
None of this makes any difference whatsoever on lead-acid self discharge.
VRLA: it's still lead-acid although the manufacturers alloy the lead a little differently. And it still can vent if overcharged. But you can't restore the lost water. Its venting is greatly reduced, compared to a flooded battery but you still need to charge it properly.
So, AGM-VRLA greatly reduces the need for maintenance but you still must maintain it.
I'm getting dizzy up here on this soap box. I hope you'll excuse me while I get down and rest.
-Dave, the Scourge of the ION