2 12 volt batterys or 2 6 volt

Gentlemen, can we agree to bring this thread to a close with a Happy Ending? Before moderators make it an unhappy locked ending?

pnichols wrote:

red31 wrote:
... are thicker plates 'easier' to recover from neglect/abuse?

The 6-volter guys always bring up the "thicker plates" defense against the 12-volter guys.

Taken at face value this is seems to make sense, but it's actually a misleading defense. 6 volt batteries MUST HAVE and BETTER HAVE thicker plates if they're going to last as long as 12 volt batteries. That's because 6 volt batteries carry twice the current per cell as 12 volt batteries carry per cell.

The caveat in my statement above of course is "all other things being equal". The 6 volt versus 12 volt discussion is rarely comparing what it should be comparing ... 6 volt apples to 12 volt apples. For instance, what should be compared is 6 volt flooded deep cycle batteries to 12 volt flooded deep cycle batteries. :)

I can assure you that a Costco 6V GC-2 carries 208 amps across the plates, while a Trojan 12V T-1275 carries 150 amps across the plates. The amps produced has nothing to do with the voltage, thickness of the plates, it has to do with what the engineers design into the battery. If the cost accountants don't screw the engineers over, they can be designed equally for amperage output. You may need 2 batteries in 6V to get to 12V, but that's got nothing do do with amperage output.

You should NEVER compare car jars, or any battery that has a "Group" in the description or naming of it... 24, 27, 29, 31, etc, to a true deep cycle battery used in traction devices, sweepers, or golf carts, or as used by some in true dry camping /boondocking non pedestal plugging in camping where you don't pay to park or hookup.

red31 wrote:
... are thicker plates 'easier' to recover from neglect/abuse?

The 6-volter guys always bring up the "thicker plates" defense against the 12-volter guys.

Taken at face value this is seems to make sense, but it's actually a misleading defense. 6 volt batteries MUST HAVE and BETTER HAVE thicker plates if they're going to last as long as 12 volt batteries. That's because 6 volt batteries carry twice the current per cell as 12 volt batteries carry per cell.

The caveat in my statement above of course is "all other things being equal". The 6 volt versus 12 volt discussion is rarely comparing what it should be comparing ... 6 volt apples to 12 volt apples. For instance, what should be compared is 6 volt flooded deep cycle batteries to 12 volt flooded deep cycle batteries. :)

pianotuna wrote:
Hi red31,

No. But because of the thicker plate they may be able to be rescued more often than thinner plate designs.

It is always a trade off.

First understand that every cycle destroys part of the positive plate. There is no way around that--but a thicker plate, under the same load, may last longer.

2nd understand that reversing hard sulfation of the plates sort of "blasts" material off the surfaces. This material falls to the bottom of the cell and may be more or less inert and can not be used to store energy any more.

The best thing to do is to charge fully each and every cycle. There are just two economical ways to do that. One is to use shore power and the other is to have a solar system.

The system needs to be designed to fit the needs of the end user. If I had more than a beer budget I'd look at LI batteries with a propane powered heating system. But....I can't justify the costs. Instead my "best fit" is 12 volt agm jars. For some other person 6 volt batteries may be a better fit.

red31 wrote:
are thicker plates 'easier' to recover from neglect/abuse?

The other advantage built into the design of 6 volt batteries is that they are taller, and the plates do not extend all the way to the bottom in the construction design. This means more shedding can fall down into the bottom of the battery before enough sheddings get high enough to short out the plates between the positive and negative sides, per cell. Advantage = 6V battery. Also, having more electrolyte capacity, they do not end up acid starved as easily as most Group 24, 27, 29, 31 car jar batteries. In general, 6V batteries don't have shape restrictions or size restrictions that inhibit them or limit them in design parameters from doing their job as best as possible. They were NOT designed to be fit or squeezed in or the tops cut off of them to fit under a slanted hood, or stuffed in next to an air filter or brake booster, or windshield washer reservoir, none of which are very good for the longevity of the battery doing what it is supposed to do, supply electricity, and recharge, many, many, many times.

pianotuna wrote:
There are just two economical ways to do that.

Don ....

I've never worked out the $-math on this, but there may be a third economical way to bring RV batteries to full charge.

For us hit-and-run type RV campers who only stay a day or two or three at any given campsite, driving between campsites in a motorhome (as opposed to a towable) can fully charge the batteries via the main engine alternator if large enough AWG cabling runs between the alternator and the coach batteries.

Only 4-6 hours of driving brings our 230 amp hour AGM battery bank back to full. At least the built-in ammeter shows zero amps going into the batteries after this amount of driving. I assume that if the batteries will no longer accept any current from the alternator, that this means they are fully charged. Is this a bad assumption?

Our situation was like this with our previous AGM batteries for years and it's turning out to be the same regarding our new set of AGM batteries. This way of fully charging our RV batteries may not be "economical" but it certainly is "not-noticeable" dollar-wise ... since we would be driving between the campsites anyway.

Hi red31,

No. But because of the thicker plate they may be able to be rescued more often than thinner plate designs.

It is always a trade off.

First understand that every cycle destroys part of the positive plate. There is no way around that--but a thicker plate, under the same load, may last longer.

2nd understand that reversing hard sulfation of the plates sort of "blasts" material off the surfaces. This material falls to the bottom of the cell and may be more or less inert and can not be used to store energy any more.

The best thing to do is to charge fully each and every cycle. There are just two economical ways to do that. One is to use shore power and the other is to have a solar system.

The system needs to be designed to fit the needs of the end user. If I had more than a beer budget I'd look at LI batteries with a propane powered heating system. But....I can't justify the costs. Instead my "best fit" is 12 volt agm jars. For some other person 6 volt batteries may be a better fit.

red31 wrote:
are thicker plates 'easier' to recover from neglect/abuse?

are thicker plates 'easier' to recover from neglect/abuse?

SoundGuy wrote:

brulaz wrote:
Well, the way *we* camp is rather a red herring.
All I'm saying above is that different people have different needs.
Seems pretty simple to me. There's no single battery technology that fits every single person out there.

The way you camp is anything but a red herring but rather exactly the point and just what I've been saying throughout this entire 10 pages of discussion. RV.NET is a public forum and as of this writing this particular thread shows 2494 views so it's obvious not just a limited few who have actually posted in the thread are interested in this topic. My point is made and IMO bears repeating because even if there's even the slightest suggestion one might camp without shore power self appointed forum pundits constantly inundate discussions like this with automatic responses that always declare the 6 volt deep cycle GC battery as the "best choice" for recreational vehicle owners when in fact the most accurate answer is it depends on how one intends to actually use their battery reserve. For many that can well mean a purpose designed 12 volt RV/Marine battery, Trojan's SCS series being an example.

I think I should start an internet ongoing concern called "Match.com" for RV battery users. Should be a pair, made in heaven. Not sure if you two need to get a room together, or a wrestling cage.

Ooooooop politics, religion, wimmens, Global Warming and now RV batteries. Sharpen them antlers and rut!

RJsfishin wrote:

Rhigley wrote:
what gives me the most bang for my money. every other rig that I have bought always had 6 volt battery's but the new one has 2 12 volt. not sure what works better.

Over the past 20 years, I've had 12'ers, then I had 6'ers, and now I'm back to 12'ers.
And w/o getting all technical,....picking each one apart for stupid little reasons, if you do not abuse them, keep them watered and charged, you will not find a dimes worth of difference between 6 & 12.
So whichever is the most AHs for the money, go for it.

:)