Installing a second battery

[bigrockbruce]

First I want to thank everyone for the valuable information I received from this website. I am comfortable now that our Monty brake problem has been resolved. We took our first trip to Mission Beach, north of Ocean Shores Washington 2 weeks ago and it sure was nice to have trailer brakes. The weather was beautiful and our first attempt of setting up and taking down went well. (Although we didn’t attempt the awning yet)
We did find a few more problems that needed to be addressed so last Friday we took our rig back to the dealer. I am a little disappointed that we should even have these quality control problems but I’ll give you an update when we get our rig back from the service department.
While we have it at the dealer’s service shop we are having 3 slide toppers installed. With a little negotiating, our cost will be $1,360 which includes labor and tax. A much better price than the $2,009.00 that we were originally quoted.
My next add on feature that I would like to do is install an additional 12 Volt battery as we will be using our Monty this winter in places without hookups. I don’t anticipate any problems in hooking up the battery and gauge so I can keep an eye on the voltage.

I do have a question as to where did you, that have second batteries, find the plastic cover for the new battery and how do you vent the fumes to the outside like the factory unit? Do they make a unit to hook into the existing vent system or is there a new cover that will cover both batteries? Any other suggestions on getting this 2nd battery hooked up properly will be greatly appreciated.
Thanks,
Bruce

[OntMont]

If you use Absorbed Glass Mat (AGM) batteries, you won't need to worry about either venting or spillage because they are sealed and don't vent hydrogen gas. I am told that two 6v "golf cart" is the best way to go. No doubt someone will be along to explain why.

Thinking about doing something similar myself, so I will monitor this thread with interest.

[Broome101]

AGM batteries not my pick, and yes they do vent just not as much. Short life for AGM batteries go with two six volts wired in series to give you 12 volts.

[padredw]

I've posted this image several times, but it seems to be highly relevant to the question just asked. This is a photo of my installation of the Bluesea Battery Box for 2 6 volt "golf cart batteries". I am very pleased with this installation.

[padredw]

Here is another thread on this same question:

http://www.montanaowners.com/forums/...rms=deep,cycle

Hope this helps.
Note the vent which uses the existing tubing. Just cut a hole to fit in the top of the battery box. We also cut a hole in the bottom using existing hole in frame. Will be glad to respond to specific questions: email, PM, or on topic.

[Clyde n Deb]

Our dealer put a second battery in our '05 2955RL before we took delivery last February. Box and venting with it. Put it right beside the existing battery. They said it was standard whenever you had 2 or more slideouts. It didn't show up as an add-on on the invoice either. Apparently this was something this dealer does on their own, and not necessarily standard practice according to Montana? I put switches on both of them, shut them off always when stored so there is no battery drain from gas detector, Fantastic Fan, etc.