Single 12v battery, or two 12v in parallel

[PhoneDude 8289]

Originally Posted by Tonybrown32

Hi all,

New to owning an RV this spring, and have a 2015 Forest River Shamrock IKSS which we are enjoying...

We still have the original battery, and it needs to be replaced.. not sure how well maintained it was by the previous owner, but 3 years lifespan is about all we will get I expect anyway..

As I'm looking to replace the original group 24 deep cycle 12v battery, I'm contemplating just getting two group 27s, as I have room for both in the battery compartment on the tounge.

We only camp 3-4 times a summer... we like to have electric hookups, but many of the state parks here in WI have the electric sites all booked up well before we are ready to plan camping weekends so don't always have electric. We camp weekends, so maybe 2-3 nights max, and without hookups, the single group 24 doesn't last us the whole weekend, and generators aren't allowed in the state parks here...

I'm thinking it would be nice to have two 12v batteries, for 2 reasons... so that on short trips, we don't have to drain the battery as deeply.. and to make sure we have enough power to last us through 2-3 days.

I don't feel like we camp enough yet to justify the more expensive AGMs, and I doubt we will get that much more life out of them to justify the cost given the way we use them, so I've decided on average 27 size wet cells for my application.

My question is, should I just hook up one at a time, and then switch the terminals to my 2nd battery once the first is depleted to around 50%, or should I just hook them both up in parallel for simplicity?

I just plug the rig into the house power to keep the batteries charged up, and don't plan on updating or upgrading the converter, wiring, etc...

Pro's and cons? Any benefits to parallel vs. just switching to the "spare" battery?

Any comments or suggestion welcome.. appreciated!

If you have not purchased a battery yet let me recommend the 12v Duracell Ultra deep cycle 120AH Group 31M. I am on my fourth year with this one, Test as good as when I purchased and put a full charge on it. I test with a hydrometer, the test light panel on the RV just don't do it.

[rk06382]

Originally Posted by Jonol

You will never beet the presision of a acid densety tester for the price!

True, but I wouldn't like to use a battery hydrometer daily to see how much power is left in the batteries. Safety glasses and gloves should always be used. Not to mention my back leaning inside the battery compartment. The RV also has limited water to wash off any accidently spilled acid.
That is why a good battery monitor is better. I'm supposed to be retired.