6 or 12 That is the question

The fact that the unit has solar indicates the intention to dry camp. In that scenario, it is all about amp hour capacity. 2 - Group 29 or 31 deep cycles are going to be right around 100 amp hours each. That should be compared to the amp hour rating of a single 6V battery.

One solar panel on the roof isn’t likely to refill even two batteries…6 or 12…for “normal” use much less if they use the inverter much.

Unlikely they would be using the Micro as it's a big draw so let's eliminate that from the equation. I assume the Inverter is item specific??? I have a 1000 and it's only hooked to the Residential Refrigerator. They have dual WH along with a dual Refrigerator.

If they dry camp a lot and need the batteries then the 6 volts are the way to go. They are a true deep cycle battery that can withstand deeper draws on their reserves and not get damaged. But the downside as ktmrfs states is the 6 volts have a high resistance. So for normal loads like lights and television and water pump and charging laptops etc they are fine. But if you try to run the microwave through an inverter they will not be able to keep up with the current draw.


If they mostly have electrical hookups when camping then they should go with 12 volts as they are cheaper and don't really get drawn down between campsites.

Cummins12V98 wrote:
Friends just bought a new 32-34' Cougar 5er (much better quality than I expected) . They have not added the batteries yet at the Dealer. They have a Solar Panel on the roof and a 2,000 Inverter. I told them to be sure they get two 6V batteries and when asked why I couldn't give an exact reason other than it's the best way to go.

So please help either tell me I am wrong and why or that I am correct and why.

Thanks!

If they expect to use the full 2000W or even 1000W from the inverter to run a microwave, don't expect a pair of 6V to work unless they are 80%+ charged. Internal resistance of 6V is the downfall for heavy loads.

If they don't dry camp much if at all, stick with a pair of the typical "marine" 12V, much less expensive and will serve the purpose well.

If they dry camp a lot, usually only use lights, ceiling vent fan, furnace etc. then a pair of GC is a good choice.

If the dry camp a lot and want to use the microwave or heavy draws (>50ish amps) often, two choices, 4 GC2's, or a pair of real 12V deep discharge batteries.

And more than likely the trailer has a WFCO charger. if they dry camp and want to charge the batteries from a generator quickly don't expect the WFCO to do much. They are seldom if ever known to go into boost mode, instead only stuffing 15A or so into the bank. Toss it out and do a drop in PD replacement and easily get 55A of charging current when needed.

If they don't dry camp much, no need to replace the WFCO

My $0.02 worth from 10 years experience with batteries, camping etc. for us and many friends we camp with.