12V Deep Cycle Battery or Two 6V Deep Cycle

[RUSSELL5000]

So, the new trailer has arrived at the dealer and is in the queue to be "prepped" and awaiting my first available time to go inspect and receive. The dealer says they put a new 12V deep cycle battery in as well as other stuff, so you are all ready to go.

I have done quite a bit of reading, and it seems that many like to use two 6V deep cycle batteries (golf cart batteries) in series. I guess the point is you increase your capacity at a lower cost.

I am wondering if I should accept the one 12V deep cycle that comes with the trailer or just arrange to have two 6V right out of the gate.

Anybody want to offer opinions on which way to go?

And yes, I do want to boondock, as it seems like lots of interesting places to came that don't have hook-ups.

Thanks!

[Camper_bob]

I would think that it would depend somewhat on what the dealer will charge you for the "upgrade". When I was shopping, I had one dealer say "the techs don't recommend that because it doesn't do much good". I didn't buy from that dealer and this comment added to the long list of reasons why.

If they won't make you a deal on 2 6V, see if they'll knock something off for not having to put on a 12V and then go get the 6Vs on your own. Call your favorite battery retailer for a price and see if the dealer can match it. If you know you're going to configure it with 2 6V, you may as well not pay for the one 12V if you can avoid it IMHO.

[WIBadger]

It's great that you're thinking about battery capacity. You could request (of your dealer) that two 6V batteries be installed (which is recommended over a single 12V battery), but I anticipate that you'll be paying too much for the batteries via the dealer. You'll also need a battery case (or cases) for the 6V batteries and it's unlikely that your dealer will have the appropriate size in stock. If you're going to boondock periodically, it might make more sense to match the dealer's new 12V battery (check the battery codes to confirm) with an additional new 12V battery having the exact/similar battery specs and wire in parallel. After you become more familiar with your energy needs, you can then upgrade to 6V batteries.

Either way, you should also consider how you're going to re-charge your batteries. I have no knowledge as to the OEM converter in your TT, but if it's not a multi-stage charger, consider upgrading that, too, along with wiring (eg, 8AWG to 4-6AWG depending upon the length of your circuit). Alternatively, a portable genny (a Honda or Yamaha) will work, but some places have restrictions on genny run times.

To summarize, it might make most sense to just add a new 12V battery (in parallel) with the dealer supplied battery, and learn/calculate your energy needs before upgrading to 6V batteries (if the dealer battery was not new, upgrading to 6V might be a better option). In any event, I'm merely making a suggestion that would be easiest for you at this time, especially as you become more acquainted with your new TT and your intended use.

[Mustang65]

I just posted this on another post, but figured you may be interested.
The 12VDC vs. 6VDC battery debate has been going on since day 1. Is there a real answer? As always, it depends on who you ask. The key thing you should consider is the batteries output. What will the Ah output of combined batteries be? (12VDC battery bank and the 6VDC battery bank) If both the 12VDC battery bank produces 200Ah and the 6VDC battery bank produce 200Ah, there is no difference. They will (should) produce the same output for the same amount of time. Battery life is based on cycles. The easy way to look at a battery cycle is 1 day. So that being said, if the batteries (6 or12vdc) will both have about the same number of cycles around 1000 cycles (3 years), they should last for the same amount of time. After that point (age) the amount of charge that the battery can hold slowly starts to drop off over time. You will begin to notice that the amount of time to charge the batteries will increase (with age). So, after about 3-4 years you will begin to notice a reduction in the batteries performance.

All things alike, the benefit is in the maintenance requirements. Maintaining 2 - 12 volt batteries vs. 4 - 6 volt batteries is a lot easier. One benefit of using 12 volt batteries is that if one should go bad (bad cell or something), you can take that battery out of the bank and the rest of the batteries will still continue to produce 12 volts. With the 6 volt batteries, if you only use 2, you have no 12 Volt battery power, with 4 or more you can rewire their output for 12 volts.

When I need to replace my 2 6 volt Trojan T145 batteries, I will probably go with 2 - 12VDC batteries .

Just my thoughts,
Don

[Mustang65]

Originally Posted by RUSSELL5000

I am wondering if I should accept the one 12V deep cycle that comes with the trailer or just arrange to have two 6V right out of the gate.

I overlooked one major question. When you decide to which battery types you want to use, do not go to the RV dealer to get them. Don't get me wrong, most dealers are GREAT, but BATTERIES are not their area of expertise.

When I was purchasing my 6 Volt batteries, I shopped around just to see what the dealers had to say and offer. They suggested 2 - 12 volt Interstate (marine) batteries and said they were the best for my needs. When I looked at the battery dates, one battery date was over a year old (I think it was 14 months old), while the other was like 6 months old. I do not believe that those batteries were properly shelf maintained, as there was a thick layer of dust on them and there were no marks on the terminals, indicating that they were being charged on a regular basis. Had I purchased them, the battery life would probably have been a lot less than a current manufacturing date. They said that this is not an issue (mfr date). I went to my first choice which was a Trojan battery supplier for the area. I got the best price also.

To get the most from your batteries purchase, purchase TRUE deep cycle batteries. The easy way to identify them is that they do not have a (Cold Cranking Amps) CCA rating in their specifications (as on car/marine batteries). The cost a little more, but you can expect a lot more output from them.

What ever you decide on, ALL the batteries that you purchase should have the same manufacture date on ALL of them.

Good luck,

Don

[RUSSELL5000]

I appreciate the responses.

I think I will just take the battery that the dealer puts in now to get me going. This is clearly an involved subject which will require that I gain familiarity with my trailer and approach to power management; i.e., a "deep cycle" of study.

[Imnaha.Mansion]

I think you are making a good decision. See if you need more for your needs and inform yourself as to what's out there.

My first pop came with one 12v. We only boondock and that one battery didn't cut it, so added another. That was OK but had to frequently recharge with 1000w generator. Then we got a TT and eventually switched it to 2 6v Trojan's, better but still requires use of 2000 Generator with a solar trickle charger. With our new FW we got 4 6v AGM and will add 600 Solar later. We only boondock so this is best for us. Your results may vary.

[Rustic Eagle]

Originally Posted by RUSSELL5000

snip....I am wondering if I should accept the one 12V deep cycle that comes with the trailer or just arrange to have two 6V right out of the gate. Anybody want to offer opinions on which way to go? ....snip

I don't know of any RV dealers that supply a "true" deep cycle battery with a new TT unless it was specifically requested (usually costs more). Most RV dealers supply a standard RV/Marine battery that has very limited deep cycle capacity.

This is my (2) 6V "true" GC2 Deep Cycle battery installation, works great for all my boondocking needs:

http://www.jaycoowners.com/forums/sh...upgrade&page=2

Bob

[Seann45]

Since you want to boondock it is best to go with the 2-6's. The plates are thicker in them, they hold a better charge and last longer.. IF you have not yet picked up the RV ask him to omit the battery then show up with a good pair of 6's and have him install them before you leave ... remember you do need a battery on the tongue to operate the breakaway switch..

[Tail_gunner]

Generally when it comes to 12v deep cycle batteries, one of two sizes are typically used, group 24 or a group 27.

When I worked as a parts guy at the local RV dealer, I noticed that a group 31 deep cycle battery was available from our supplier. I was curious and found out the group 31 battery fits inside the group 27 battery box. A size 27 box was usually the largest box most RV's would accommodate. So as long as it fit in the box, a stronger group 31 could be used. So I hooked up my favorite customer with one, namely "ME".

When we upgraded to our current Eagle 284BHS, I wanted to have as much battery capacity as possible. The battery box mounting locations on the tongue would accommodate 2 batteries, but not 2 group 27 boxes. The front one was not long enough for a 27, just a 24. I modified the forward mounting location to accept a size 27 box. I was then able to use dual size 31 batteries. My previous thread showing the dual battery mounting mod

I know 6 volt batteries are heavy. But how they compare to 12v batteries namely group 27 or 31's, I don't know. But I know the twin 31's are REAL heavy. But weight isn't a real concern with me. I have weight capacity to spare with my GMC Duramax.

[Imnaha.Mansion]

The base sizes do not vary a whole lot, height does. When I was deciding on batteries for my new trailer size was a big issue, but I wanted plenty of capacity as I will be eventually adding Solar and an Inverter. So went with 4 Lifeline 6v AGM Batteries, quite pricey. They are almost 100 pounds each so installation planning must account for the weight. This setup should give me 600Ah at 12V. I do have concerns about being able to charge them adequately till I get Solar, but he generator is being installed right now.

I've heard that generally the better the battery the heavier the battery, as the plates are thicker.

As far as tongue weight, you shouldn't be so close to your limit that a few pound difference is much of a factor.