Four Batteries vs. Two

[coasttocoast]

In my 2016 Interstate, I have the stock 2 batteries. I do have 300 watts of solar. Has anyone upgraded to the 4 battery system by adding the brackets, wires, and 2 additional batteries? I would have this done at the Mercedes/Airstream dealer. How has this affected performance with the amount of time the batteries last after sundown? Currently, I believe if I leave the fridge and freezer running overnight to around 9am, the batteries will be run down to the point of potential damage. Of course, the inverter and alarm and sub pull some current. The batteries are currently in perfect condition.

My wife and I are planning a west coast trip, and we have a pile of hotel points that we might use along the way in some places. I want to be able to park the vehicle overnight with the fridge and freezer running and not have to worry about batteries.

There are other times where I find myself in the middle of nowhere on a cool night and don't need AC or heat and would like to be able to just pull over without worry of battery capacity.

If you have installed this package through an Airstream dealer, what are you paying? If you have a new Interstate with 4 batteries, how is it performing?

thanks

[rowiebowie]

I have seen previous posts of Interstate owners who have upgraded to 4 batteries. Unfortunately in a few cases, their added battery boxes did not hold up to the extra weight and dumped the extra AGMs on the roadway.

I'm sure they will be along shortly to advise you on how they liked the extra battery capacity and also how to make sure the are supported correctly.
.

[Tobbun]

Take a look at Wachuko’s “The journey begins thread” he did the work himself. Be warned your todo list grows the more pages you read on that thread.
As Rowiebowie mentioned others have seen mixed results with having the work done elsewhere. It seems like 400 watt solar and 4 AGM batteries plus controller upgrade allow you to be pretty self sufficient.

[TN Princess]

I have a 2017 Interstate. I added 2 additional 12 v batteries. With night time temps in the 70 - 80 range, I can run the frig over night. Can not run freezer and frig. I have used frig only several times when we will spend the night in a motel with no place to plug the Interstate.

No problem with brackets holding up. Those who talk of bracket failure have changed to 6 volt batteries. 6 volt batteries weigh more than 12 v batteries.

I install extra batteries with the Interstate parked in my driveway.

[wachuko]

Correct. Those that had issues with their trays had heavier batteries installed.

If you do the install yourself, make sure you use stainless steel rivets to secure the trays. And go with stock size batteries.

Let me get you the direct link to where I started to do the install. Here you go:

http://www.airforums.com/forums/f240...ml#post2046122

I took several pages for this as I was also doing the BlueSea ACR and the Solar controller... so be ready to go over several pages... I should have created a separate thread documenting it but was lazy....

[c21]

My wife and I are planning a west coast trip, and we have a pile of hotel points that we might use along the way in some places. I want to be able to park the vehicle overnight with the fridge and freezer running and not have to worry about batteries.

On our 2014 AI Twin with interior batteries we changed to 6V AGM's and could easily leave it in a hotel parking lot overnight with the frige running. I believe you have seperate frige and freezer while we had an internal freezer in the frige. Not sure what your power draw would be but do keep in mind that you won't be accessing the frige overnight which help it stay cool. You might want to run a test in your driveway and see how it performs.

thanks[/QUOTE]

[Jdurossjr]

No sure where to start with this info. We removed the2-12V AGM batteries and replaced with 4- 6V AGM’s. We also added a solar panel to get to 400 watts. My wife and I have only plugged in once. We have had no issues with the test. Did about 8K miles last year. The work was done in Ohio by the factory.
I am getting a lesson on batteries. They need to be plugged in to restore to full charge.

[VAtom]

Not a direct response to the OP but I added 2-12V AGM to the 2014.

They are safely inside and not under-slung. I also changed the embarrassingly anemic solar from 50w to 150w.

To be brutally honest, the new set up allows the small NovaKool to remain running all night and that's about it.

I could probably watch TV, if I watched TV or use the induction cooker or coffee maker for a short period.

Dreams of endless boondocking are, alas, still dreams.

[Mcrid]

Much information on the site on how to upgrade fro extended Boondocking. Here is a thread that was very active a while back.

http://www.airforums.com/forums/f240...ml#post1806655

I'm now looking at the Volta system and will be visiting an installer Wednesday to see what all is involved. If you follow the thread above, you will see I also changed to a MPPT Solar controller and it does make a difference. We have no problems with 24 - 36 hour runs with our tired 4 batteries.

[swilly43]

I am in the process of assembling the parts to perform an upgrade to 4 6V lifeline batteries in place of the 2 12V This will triple the available amp hours available to safely use the batteries. With the 2 GRP 24's you have 80 useable hours. With 4 6V lifelines you have 220 AH. Ok not quite 3 times. I purchased the OEM battery trays for the passenger side. I will remove the existing trays on the driver side. I will cut the trays in half and lap weld in 14 G steel to increase the width by .5 inch to accommodate the width of the 6V. I will use the Airstream specified or stainless steel rivets with as yet to be determined approach to secure the heavier batteries. Other posters have shown how to do this but I am looking at a different approach. The cost of the 2 battery trays was about $300. The cost to split all four trays, weld in a patch and paint is about $300. So for about $2K I can almost triple my AH's. I will post when I get it all done in about a month. I investigated a custom tray but this was turning out to be much more expensive and time consuming.

[Ryoungca]

I used a different approach to adding the additional amp hours. In my case I removed the existing battery box which was under the back seat and converted the rear storage box to hold 4 X 6 volt Lifeline golf cart batteries (GPL-4CT). Phaeton313 had the initial idea. Here is the main thread:
http://www.airforums.com/forums/f240...es-172072.html
and this is a link to the completed installation in my van
http://www.airforums.com/forums/f240...ml#post2038448
I've been very happy with the extra capacity, 2+ days of boondocking.

[Boxster1971]

Originally Posted by swilly43

I am in the process of assembling the parts to perform an upgrade to 4 6V lifeline batteries in place of the 2 12V This will triple the available amp hours available to safely use the batteries. With the 2 GRP 24's you have 80 useable hours. With 4 6V lifelines you have 220 AH. Ok not quite 3 times. I purchased the OEM battery trays for the passenger side. I will remove the existing trays on the driver side. I will cut the trays in half and lap weld in 14 G steel to increase the width by .5 inch to accommodate the width of the 6V. I will use the Airstream specified or stainless steel rivets with as yet to be determined approach to secure the heavier batteries. Other posters have shown how to do this but I am looking at a different approach. The cost of the 2 battery trays was about $300. The cost to split all four trays, weld in a patch and paint is about $300. So for about $2K I can almost triple my AH's. I will post when I get it all done in about a month. I investigated a custom tray but this was turning out to be much more expensive and time consuming.

SWILLY43 - good choice of method to add more batteries.

[Jack Houpe]

We installed an additional 4 T105 golf cart batteries in parallel to the 2 agm batteries, now we have 380 amp hour total. We don't boondock all that much but its nice to know we can go 3 days on the refrigorator without the voltage dropping below 12.2 volts. Had to build a air tight box with a vent to the original box which is vented outside. Works very well so far been over a year. Recently we converted to twin beds, here is a picture of the 2 boxes, both are black. Sorry about the picture being sideways.

[AI Joe]

Hah Jackson Center install 4 6v Lifeline batteries to our 2016 GT in October 2017. Added 2 solar panels for 300w. Fall 2019 replaced the original Atkinson controller with their new “MPT” controller designed specifically for the Lifeline spec and can run fridge and freezer all day and end day with 100% batteries; so could theoretically run all night and be OK, but usually shut off freezer overnight and all is well. Check out the new Atkinson controller: contact abnerj@atkinsonel.com. It is a simple “plug & play” install that takes less than 2 hour. Also, check out the through the roof plug connection done by Airstream-had to hardwire on my 2016 as the original Airstream connection was very poorly thought out.

[AI Joe]

Had Jackson Center install 4 6v Lifeline batteries to our 2016 GT in October 2017. Added 2 solar panels for 300w. Fall 2019 replaced the original Atkinson controller with their new “MPT” controller designed specifically for the Lifeline spec and can run fridge and freezer all day and end day with 100% batteries; so could theoretically run fridge & freezer all night and be OK, but usually shut off freezer overnight. Check out the new Atkinson controller: contact abnerj@atkinsonel.com. It is a simple “plug & play” install that takes less than 1 hour. Also, check out the through the roof plug connection done by Airstream-had to hardwire a new one on my 2016 as the original Airstream connection was very poorly thought out and severely corroded.

[swilly43]

AI Joe, Would you be able to provide details or pictures of how the factory supported the larger batteries? I have already installed my new (wider) battery boxes but it would be informative to see how the factory did it. I will have my install complete by this week and will post the project at that time. Thanks to all who have provided input so far.

[AI Joe]

Originally Posted by swilly43

AI Joe, Would you be able to provide details or pictures of how the factory supported the larger batteries? I have already installed my new (wider) battery boxes but it would be informative to see how the factory did it. I will have my install complete by this week and will post the project at that time. Thanks to all who have provided input so far.

Attachment 1. Factory adjusted size of box and put back where it was, added two more to opposite side and wired it up. Boxes were adjusted by welding about a 1” spacer to accommodate new batteries. Attachment 1

[Boxster1971]

Originally Posted by AI Joe

Attachment 337063Attachment 337064Attachment 337065Attachment 1. Factory adjusted size of box and put back where it was, added two more to opposite side and wired it up. Boxes were adjusted by welding about a 1” spacer to accommodate new batteries. Attachment 1

From the photos looks like the factory did nothing to add support to those heavier batteries. They just made the boxes bigger. I thought they were adding more support after the reported problems with the batteries falling down.

[Jererae]

I did the 200 watt solar upgrade and I upgraded the controller. By upgrading the controller - I have found that I have basically no issues. Before the solar upgrade - I was constantly running out of battery power. The additional 200 watts of solar insures that I can be self sufficient during the day when the vehicle is parked. I had planed to add additional batteries if needed - but continue to postpone that decision. I have the 2017 AI

[swilly43]

I completed my upgrade to 4 6V Lifelines. Please see attached write up. Thanks to all who commented and provided support during the process.Battery Upgrade.pdf