Best practice for battery while sitting for long periods of time?

[Penny Loafer]

Hi all!
I have a 2016 27FB, purchased this past June. I have taken it on a couple trips but nothing too large this summer because as of May we had no intention of buying a trailer at all and thus had not booked off any time.

So for this summer she has been sunning herself in my driveway, plugged in to the house to run the lights and fans etc. I love having it right out the back door as a reading nook/getaway and a second bedroom when needed.

Our intention is to store it there through the winter as well, so we will winterize the pipes and tanks etc, but I'm wondering - What is considered the best practice when it comes to the battery/electrical - is there any harm in leaving it plugged in continuously for months on end? Does that prematurely age the battery? Is it better to let it run down completely on occasion and then recharge it?

Thank you in advance for your words of wisdom on this issue and my apologies if it's been covered extensively elsewhere - sometimes I find the sheer volume of archived information to be overwhelming to navigate.

[Boxite]

Keep it charged, either by a battery-maintainer/trickle-charger, or by a quality onboard converter.
That last option is a challenging discussion on the forums. If you follow the most prolific advice you'll spend a lot of money on sophisticated converters trying to save a $100 battery....not worth it, IMO.

My little trailer has it's original WFCO converter which has stayed plugged-in now for two years and the 3-yr-old WalMart, cheap flooded cell battery is doing just fine with an annual addition of distilled water. (WFCO is hated by some, but I'm not sure those who hate it have had any experience with it. It's often said that a multi-level converter is necessary for battery longevity and the WFCO is a 3-stage charger, so I don't understand what the claimed problem is. My experience so far is good with it, and it's one of the least expensive on the market. If it dies I'll buy another just like it, but so far it's not indicating any weakness and it's 8 years old.)
So... if you have a common flooded cell battery, keep it charged so it won't freeze or sulfate and will last long.
Hope that helps.

[Rich W]

If you are using it as a reading room, winter included, I would just leave it plugged in all the time. You'll have AC power and the converter will provide the DC and charge the batteries. You don't want to overcharge, so when you leave the AS to go back inside, put the switch by the door to 'store'. AC and DC power will be on, but it won't be charging the batteries. If you go out there daily for an hour, batteries should stay charged. When you go back to read, turn it back to 'Use'.

I have a solar panel and the internal monitor has a voltmeter so I can check the charge. You might want to see about having a small voltmeter plugged in. The voltage should be between 12v (discharged) and 12.7v (charged). When the charger is running the voltage will be about 13.3 so to check, you want the switch in 'store' for a couple hours before you check it.

The best state for a battery is fully charged with occasional discharge. You never want to fully discharge a wet cell, it shortens the life each time that happens and will sulfate if you leave it discharged; all bad things.

If it is not a sealed battery, you need to check the water level occasionally. I'd check monthly and if you don't need to add distilled water then bi-monthly.

I envy you, having it right outside. We have to keep ours in storage 22 miles away.

[68 Overlander]

I'm sure you have a Parallax converter and it will not drop back to a float/storage mode. You will need to either pull them and store inside, disconnect the batteries (You probably have DC shut off switch) and connect a maintainer to them, or upgrade to a 4 stage like the PD4655 that many have done (assuming you have 30 amp service)

[lewster]

If you intend to remain plugged in, put the 'use/store' switch to 'store' and remove the batteries. Bring them into your garage and get a battery maintainer to keep them happy till spring.

Your Parallax single voltage converter WILL still provide all of the 12VDC that the trailer needs while you are plugged in. No batteries required!!!


Lew Farber

[Beamer]

I've just retired from working on BMW motorcycles for 36 yrs. One observation I made was battery life with customers. The battery that was cycled up and down regularly by being used daily lasted the longest. Of course, the batteries that were left to discharge for long periods died quickly.
Also, the batteries that just sat on a trickle charger for long periods without use died almost as quickly as the ignored batteries.
I compared it to our health. You can't sit on the couch and eat vitamins and expect to live long.
I think the best product would be a charger/load combo devise that works the battery for a couple hours, then recharges it, like an exercise program.

[WindyJim]

I have a 25' AS with a single 100 watt solar panel on the roof. I keep it in the back yard when I'm not using it and never plug it in (unless I decide to run the air conditioner or the microwave, which I sometimes do if I'm using it for a reading room). I know the solar controller charges it to 14.02 volts daily. I have two Trojan 6-volt batteries in series and am very happy with the system performance.

Having said all that, I don't know if this is this is doing what is best for the batteries. I know the 6-volt golf cart batteries typically last a lot longer than the 12-volt batteries, so I hope this is a satisfactory way to operate.

Any comments as to whether or not this is the proper method for maintaining my system would also be appreciated.

[franklyfrank]

Originally Posted by Boxite

Keep it charged, either by a battery-maintainer/trickle-charger, or by a quality onboard converter.
That last option is a challenging discussion on the forums. If you follow the most prolific advice you'll spend a lot of money on sophisticated converters trying to save a $100 battery....not worth it, IMO.

My little trailer has it's original WFCO converter which has stayed plugged-in now for two years and the 3-yr-old WalMart, cheap flooded cell battery is doing just fine with an annual addition of distilled water. (WFCO is hated by some, but I'm not sure those who hate it have had any experience with it. It's often said that a multi-level converter is necessary for battery longevity and the WFCO is a 3-stage charger, so I don't understand what the claimed problem is. My experience so far is good with it, and it's one of the least expensive on the market. If it dies I'll buy another just like it, but so far it's not indicating any weakness and it's 8 years old.)
So... if you have a common flooded cell battery, keep it charged so it won't freeze or sulfate and will last long.
Hope that helps.

Ditto, we have ours plugged in 24/7/365. Stock converter with the original Interstate batteries it came with over three years now. I keep it clean, check them before every trip and all they need is an occasional addition of distilled water. Mainly when we are wintering with it in FL.

[A W Warn]

If you are going to "use" the trailer at home occasionally during the winter I assume you would want to leave the batteries in place. (I would)
A charged battery will not freeze. If batteries are discharged, possibly they could freeze and burst, leaking the acid.
When I stored my trailer over winter prior to replacing the converter with a multi-charge rate one, I used a timer on the receptacle where I plugged in the power cord. 2 to 3 hours per day should keep your batteries in good shape. Since I replace the converter in my 25' a few years ago, I leave it plugged in 100% of the time it's parked/in storage.

[lsbrodsky]

Please note that 68 Overlander and Lewster are professionals in this discipline. I would weight their advice the most.

Larry

[lewster]

Originally Posted by Boxite

Keep it charged, either by a battery-maintainer/trickle-charger, or by a quality onboard converter.
That last option is a challenging discussion on the forums. If you follow the most prolific advice you'll spend a lot of money on sophisticated converters trying to save a $100 battery....not worth it, IMO.

My little trailer has it's original WFCO converter which has stayed plugged-in now for two years and the 3-yr-old WalMart, cheap flooded cell battery is doing just fine with an annual addition of distilled water. (WFCO is hated by some, but I'm not sure those who hate it have had any experience with it. It's often said that a multi-level converter is necessary for battery longevity and the WFCO is a 3-stage charger, so I don't understand what the claimed problem is. My experience so far is good with it, and it's one of the least expensive on the market. If it dies I'll buy another just like it, but so far it's not indicating any weakness and it's 8 years old.)
So... if you have a common flooded cell battery, keep it charged so it won't freeze or sulfate and will last long.
Hope that helps.

Perthaps, but many folks aren't satisfied with the lack of performance from $100 batteries and upgrade to quality batteries that far outlast the garbage that's available. All batteries ARE NOT created equal!

And BTW, your WFCO converter IS an automatic 3 stage unit, even though it is of Chinese origin and is the #1 replacement that I do in SOB trailers. Airstream used them in very limited numbers in some of the Sport line, but ALL regular Airstream trailers still get the Parallax POS that will cook a battery quicker than you can blink your eyes.

To many, dealing with the issues of cheap, liquid cell batteries like constant maintenance, outgassing that causes corrosion and lack of long term capacity are just not worth the hassle. After all, Airstream IS a luxury brand of RV.

[Northerngirl]

Originally Posted by 68 Overlander

I'm sure you have a Parallax converter and it will not drop back to a float/storage mode. You will need to either pull them and store inside, disconnect the batteries (You probably have DC shut off switch) and connect a maintainer to them, or upgrade to a 4 stage like the PD4655 that many have done (assuming you have 30 amp service)

I am having to put my trailer into storage this winter and will get little use of it. I have been considering a battery maintainer as the trailer will be stored indoors and power is available. I have an older Parallax that is not a smart charger.

So if I am understanding the above correctly I can just shut it all down with the DC storage/shut off switch and connect the maintainer? or do I need to disconnect &/or remove the batteries in order to leave the maintainer running?

[Penny Loafer]

Thanks to each of you who replied with such helpful and detailed responses!

I've learned a ton from this board over the last 4 months, and that's just been the tip of the iceberg, I'm sure!

Thank you again for taking the time. Truly appreciated


Jennifer

[68 Overlander]

Originally Posted by Northerngirl

I am having to put my trailer into storage this winter and will get little use of it. I have been considering a battery maintainer as the trailer will be stored indoors and power is available. I have an older Parallax that is not a smart charger.

So if I am understanding the above correctly I can just shut it all down with the DC storage/shut off switch and connect the maintainer? or do I need to disconnect &/or remove the batteries in order to leave the maintainer running?

Depends on whether you have power where you are storing it. If you have power there, connect a maintainer. If you don't have power there, you will need to pull them to a place that does. Another option is a solar maintainer depending on where you live or store the Airstream.

[Northerngirl]

Originally Posted by 68 Overlander

Depends on whether you have power where you are storing it. If you have power there, connect a maintainer. If you don't have power there, you will need to pull them to a place that does. Another option is a solar maintainer depending on where you live or store the Airstream.

Thanks. It will be stored away from my home indoors with a power supply.
I have solar and its is what I have been using when the trailer is stored at home.

[Caffeinated]

I have a 2015 27 ft FB FC. Your trailer but one year older. My interstate batteries failed completely one month out of warrenty. I believe their failure came from becoming overly discharged while sitting on the dealers lot and also while in my storage site due to parasitic battery drain. The "store" switch does not shut off all the current from the battery. I replaced the one year warrenty interstates with three year warrenty Trojan batteries. I also replaced the factory Parallax single stage converter with the Progressive Designs 4655. I now completely disconnect all the positive leads from my battery's when I store the trailer for a short time, insuring there is no parasitic discharge. When winter comes, I'll pull the batteries from the trailer, and store them in my garage where I will put them on a battery tender from time to time to insure they stay topped off. I've learned the hard way.

Mike

[Trailbob]

I recently upgraded to the PD4655 converter, but prior to that I kept a Battery Tender or Ctek battery maintainer connected to the batteries when the trailer was in storage. I rarely had to add water to the batteries.

My original Interstate batteries are over 3.5 years old, and still working well. But I will be upgrading in the near future to higher quality batteries, probably 6Vs, for more capacity.

[centennialman]

So......I guess I will pull the batteries from my 2016 FC20 (Interstates) and put them in the garage with a trickle charger on them for the winter. Or, if I am not moving the trailer at all....is it ok to leave them hooked up to the trailer with the charger on them? Which is best? I have been diligent in keeping them charged with either periodic shore power charges or a solar panel during this summer.

Time to get ready for winter

[OTRA15]

Steve, if I lived in Colorado, I think I would be inclined to pull the batteries and store them in the garage with the trickle charger, as you will have better access to them, and more control over them not freezing during a winter power outage etc.. We are planning another short trip or two this Fall, but have started making plans for the winterization process as well.

Happy Trails.

Peter

Originally Posted by centennialman

So......I guess I will pull the batteries from my 2016 FC20 (Interstates) and put them in the garage with a trickle charger on them for the winter. Or, if I am not moving the trailer at all....is it ok to leave them hooked up to the trailer with the charger on them? Which is best? I have been diligent in keeping them charged with either periodic shore power charges or a solar panel during this summer.

Time to get ready for winter

[centennialman]

Thanks Peter - it actually gets cold enough to freeze in the garage as well. I guess I could cart them down to the basement and hook them up there.

I was hoping the trickle charger would be enough to keep them from freezing if I left them hooked up to the Airstream.