I just upgraded my batteries to dual 6V. I had enough trouble figuring out the mounting, that I thought I would share this with the group.

My unit is a pull-behind conventional travel trailer. Like most of them, it has a rack for batteries on the tongue next to the propane cylinders. The rack sits between the vee rails. Often the dealership will sell you a single group 24 battery with box, because that's the cheapest and they figure you don't know the difference. Often a second group 24 will fit in the same rack, and you can double your amp/hours. But group 24 are pretty anemic at best.

My trailer had a single group 27. A group 27 has a bit more capacity, and is larger, but two group 27 will not fit between the rails on any travel trailer that I have ever seen. So to add a second group 27, I had to build my own rack up on top of the rails. That worked out okay for a couple of years for me. I should add that, it's not really the battery size that is a fit problem, it is the battery box sizes. They make a group 24 box, and then they make a group 27 thru 31 box. That box is a lot larger than it needs to be, and two of them just won't fit. You can see the bolts that were used for my custom rack in the photos below.

Furthermore, a 6V battery is very close in size to a group 24 in L x W, but it is a couple of inches taller. It will not fit a group 24 box. A good RV store will have specific 6V boxes, and they are almost exactly the same L x W but are taller. Look around and you'll find them. Made by Naco, just like the other boxes. Bottom line is that, on most trailers, two 6V will fit in the factory rack if you get the correct boxes.

Why 6 Volt? They are essentially golf cart batteries. They are true deep cycle, which is not true of most 12V. Each battery is heavier, because they have more lead to acid contact surface.

Be sure to wire them correctly. They must be wired in series to yield 12V.

Pictures:

 

what was wrong with the 27's you originally had?

 

They were just tired. Didn't hold a charge for very long. That's the problem with fake deep cycle batts. If you run them low, they break down fast.

I did that to them by dry camping without a generator. Now that I have a genset, I can be nicer to my batts and hopefully get better life.

 

You'll enjoy the 6 volt. I am on my second set. The first set lasted 9 years and that was on an 95 fiver that didn't have the better converter/charger like the newer units have now. Just remember to keep adding distilled water to them and you should get long use.

 

Could you pass on how these need to be wired. I have been reading about doing this same thing on a boatng forum I visit. Seems to be some folks using the 6 volt batteries in their boats because of the same benefits you mention. I will be replacing the battery in my fiver and one in my boat so may have some interest trying this.
badger5301@netins.net
Thanks in advance for the new ideas

 

connect the postive of battery #1 to the negitive of battery #2, then use the open ends of each battery for your output.(neg to your ground wire and pos. for your +12 volts)

 

Right. You want to wire them in series. Keep in mind that you will always need at least two batteries. If you have more than two, you will need them in pairs.

You can see by the wire sizes how I wired my two in series. The big wire is the jumper between pos and neg terms. The small wires go to the trailer.

 

Have a look at this article on upgrading your RV batteries to 6-volt golf cart batteries. There are a few diagrams of how to wire up 2 and 4 6-volts and also some reasons for doing the upgrade.

6-volt Golf Cart Battery Upgrade | ModMyRV