Buying new batteries, 6V or 12V what is better?

I have a 2007 WW FSC3200 and i am looking to by new batteries but I don't know what to get. Is it better to get 2 12V batteries or get 2 6V batteries? What are my advantages to these choices? Any recommendations would be greatly appreciated.

Thanks, Rob

Bob, you will get many forms of advice on this subject.  Also search our library for more information on batteries.

The important thing is to get true deep cycle batteries.  Usually 2 - 6V golf car batteries wired in series will provide more amp hours (usable reserve capacity) than their 12V cousins.  JMHO

So the best recommendation is to use 2 6V batteries. 

  Thanks,

Assuming you're talking about wet-cell batteries (not Optima or other AGMs), two 6 volt batteries are better than two 12 volt batteries.

Golf cart batteries are true deep cycle batteries - they're made for long, deep discharge cycles.  Due to economies of scale (they have a huge market in electric golf carts) they're pretty much the best bang for the buck.  Too often 12 volt "RV/marine" deep cycle batteries are a compromise between deep cycle and starting uses, not really best for either use. 

The dual 6-volt version has half as many cells, so for a given total amp-hour capacity, each cell will be twice as large as the cells in the 12 volt version.   Bigger is better in deep cycle usage - larger plates, more electrolyte, etc.

The 6 volt batteries will be connected in series, meaning there's one and and only one current path through them.   All of the cells are charged and discharged at equal rates, keeping them in balance with each other.

A pair of 12 volt batteries connected in parallel divide the current between the two batteries.  Under ideal circumstances, each battery will get half of the total charging current and will contribute half of the load current.  But things are frequently less than ideal.  A little bit of terminal corrosion, unequal amounts of wire resistance or changes in the battery's internal resistance frequently make one battery work harder than it's mate, decreasing the overall performance of the pair.

6 volt batteries are slightly taller than their 12 volt counterparts - make sure you have enough vertical clearance for them.

In the past I have done several "Bang for your buck" comparisons on batteries and to date the six volt golf car batteries, which as others have mentioned are flooded wet cells (The kind you add water to) gave the most Bang (Amp hours) for yout dollar investment.

So.. That is what I recommend.

NOW there are things happening that may change that down the road.. (mostly 36 volt golf carts that use six 12 volt bateries instead of six volt like the 18 volt carts do)  but that's down the road.

And of course a good sale can make a difference

Costco and Sams usually have good prices but finding six volt can be a trick.

Lou Schneider said:

Assuming you're talking about wet-cell batteries (not Optima or other AGMs), two 6 volt batteries are better than two 12 volt batteries.

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Well and crisply said.  This should go in library.

Joel

I agree, Joel,

Almost every time this subject comes up the smoke gets so thick it's hard to tell if everyone is saying the same thing or not. JMHO

An accurate and concise library piece to point to would be great. 

We've had this article in our library for some time. I suppose it could do with a little embellishment.

Tom, that is an excellent article, but it doesn't address the blunt question of;
 
"Is a two 6v battery arrangement superior to a one or two 12v battery arrangement?"

I guess I liked Lou's response to this particular post because it made a few statements and supported each of them with concise explanations, if not facts.

Lou,

You're welcome to rewrite the article  ;D  I consciously didn't offer a link to the article earlier in this discussion because I'm aware of the conflicting opinions that exist.

Tom,

I was trying to take "opinion" out of the equation.

I wouldn't want to rewrite the existing article as it does a good job of supporting it's title and objective.

If I can come up with material for an additional article that might just be a collection of "opinions", re-packaged as "conventional wisdom", to answer the 6v v/s 12v question, I'll submit it for your consideration. ;D ;D

In the mean time, keep on keepin' on.  You do a great job, and I mean that seriously, in spite of all us experts and critics.

In the mean time, keep on keepin' on.  You do a great job, and I mean that seriously, in spite of all us experts and critics.

Click to expand...

Thanks for the kind words Lou, much appreciated.

I've been a proponent of golf cart style batteries for many years, for the reason that Lou S stated. But, I've modified my position from "this is the best (only) way to go", recognizing that there are alternatives.

There's also a couple of paragraphs on selecting batteries in this article, but there's other stuff in there that's not relevant to this discussion. So, again, I hesitated on posting the link.

The simple answer is as Lou says: Any 6v golf cart battery is a better deep cycle than 98% of the 12v batteries brands offered to RVers in RV & automotive stores.  And in many cases the cost, when amortized over the life of the battery, will be notably less as well. The bottom line is you get more amp hours for less money and they last longer.

In the interests of technical accuracy, there are excellent 12v deep cycles available from manufacturers such as Trojan, but they are mostly special order items and quite pricey.

AGM or gel batteries are a different question and bringing them into this discussion confuses the issue.

Thanks to all for you input, I did go ahead and purchased 2- 6V batteries form CostCo, they work great!!  Once again Thank you All


  Robert

COngrats on a good choice... One standard Which I may have mentioned is "Bang for the Buck"

I recall a car and driver type magazine that tests out "hot cars"in a "Bang for the Buck" oh they get all the big names in sports cars sending them product to test but more often than not the winner,  is the relatively lowely JEEP

Why, because when you divide the amount of fun you can have with a jeep (BANG) by the price tag (BUCK)  Well... It beats Lamborghini 9 times out of 8!!!

Same here, when you divide amp hours by dollars.. IT don't get much better than Costco Golf Car batteries

Now a question... If you have the receipt handy.. What is the SKEW or other Catalog number for that item.. Thanks

Lou (onaquest) said:

Almost every time this subject comes up the smoke gets so thick it's hard to tell if everyone is saying the same thing or not. JMHO

Click to expand...

Lou,

I see what you mean by smoke!

Richard

Naa. if you hook 'em up right, there is no smoke

Now hook 'em up wong... And you can get a WHOLE LOT of SMOKE!!!!!

If you venture any opinion at all here, you will get lots of SMOKE! Certainly much more than light!

Is there any problem using a 6v in an RV due to chargers being wired for 12 v?

I am a major novice when it comes to batteries and wonder if I put 6v batteries in will they, or the RV get messed up due to charger issues?

I have an '05 Itasca if that matters.

What are GSM batteries and are they worth looking at?