2 x 12 volts or 2 x 6 volts batteries?

In general terms (all else being equal): 12V batteries have double the voltage but half the amp-hrs

The net effect is two of either are about the same for overall voltage and amp-hrs.

In reality all things are not equal. As mentioned, 6V batteries are typically true deep cycle batteries and will provide more overall amp-hrs.

The available amps (think cranking amps from car batteries) is generally not relevant to house batteries. Even a big inverter pulling 3600watts is only going to draw around 300amps, which should be no problem for a pair of 6V deep cycle (I'm talking amps not amp-hr which is a much different measurement and of course, 300amps cannot be sustained for any significant length of time for any reasonably sized battery bank before it goes dead). For normal house loads, the amp draw is typically under 20amps (often less than 5amps) so CCA ratings are pretty much irrelevant.

If you have DC loads that require more than a single battery 6V is really the way to go.

2oldman wrote:

Kidoo wrote:
I was planning a tempory installation of 3 x 6 volts to get more juice. Two in parallel and one in series with the two parallel, isn't it possible, I am just about to connect the setup!

It's possible, but won't get you 'more juice.'

What you're doing is connecting a big 6v battery (the 2) in series with a smaller one. The current will be limited by the smaller one, so the 3rd battery will be redundant.

kinda of ridiculous I guess I should have said.no one does it and
there would no defined reason or advantage.

Of course it's possible. You know what you are doing.

Batteries are like containers. Having two containers will give you the available power from two. Having three containers will give you the available power from three.

Kidoo wrote:
I was planning a tempory installation of 3 x 6 volts to get more juice. Two in parallel and one in series with the two parallel, isn't it possible, I am just about to connect the setup!

It's possible, but won't get you 'more juice.'

What you're doing is connecting a big 6v battery (the 2) in series with a smaller one. The current will be limited by the smaller one, so the 3rd battery will be redundant.

Kidoo wrote:

MrWizard wrote:
Not a useful comparison
You can't use (3) 6's in an RV, you need two or four

Two sixes is still only 245 amp hrs at 12v
And two 12's will be from 160>210 amp hrs, depending group size and rating
Cheap grp 24 75 amp hrs each
Good grp27 110 amp hrs each

In many cases when going fla batteries, 6v GC give the best results,
Unless you are planning for heavy inverter loads,, then 12 AGM give better results

One of my 6 volt AGM battery failed, it read 4.2 and the other reads 6.4. I need some batteries to get me going until I am in USA to buy new ones at Costco or Sam, none available in my Costco. I have two old acid 6 volts, still useable but not very strong, that I want to pair with my 6 volt AGM.

I was planning a tempory installation of 3 x 6 volts to get more juice. Two in parallel and one in series with the two parallel, isn't it possible, I am just about to connect the setup!

no u cant use Three 6 volts at all TWO or FOUR must be used

on a side note buying six volters at Costco in usa will cost u about 116$ cdn;;don't know what its like in Quebec but in BC you can buy Rv six volts for $115.00 cdn so really don't understand your point at all

MrWizard wrote:
Not a useful comparison
You can't use (3) 6's in an RV, you need two or four

Two sixes is still only 245 amp hrs at 12v
And two 12's will be from 160>210 amp hrs, depending group size and rating
Cheap grp 24 75 amp hrs each
Good grp27 110 amp hrs each

In many cases when going fla batteries, 6v GC give the best results,
Unless you are planning for heavy inverter loads,, then 12 AGM give better results

One of my 6 volt AGM battery failed, it read 4.2 and the other reads 6.4. I need some batteries to get me going until I am in USA to buy new ones at Costco or Sam, none available in my Costco. I have two old acid 6 volts, still useable but not very strong, that I want to pair with my 6 volt AGM.

I was planning a tempory installation of 3 x 6 volts to get more juice. Two in parallel and one in series with the two parallel, isn't it possible, I am just about to connect the setup!

MrWizard wrote:
Not a useful comparison
You can't use (3) 6's in an RV, you need two or four

Two sixes is still only 245 amp hrs at 12v
And two 12's will be from 160>210 amp hrs, depending group size and rating
Cheap grp 24 75 amp hrs each
Good grp27 110 amp hrs each

In many cases when going fla batteries, 6v GC give the best results,
Unless you are planning for heavy inverter loads,, then 12 AGM give better results

on contraire its very usefull in showing where in most cases the use of two 6v batterys has a better amp hour rate than a single twelve
or in the case of a golf cart 6x6 is double the good of 3x12
why cant u use six 6 volts or Three twelve Volt in a RV?
The very best rating for a 27Rv even at 210 if u can find one is
actually 125amp hours and there expensive.
I had no idea though that 12V AGM were far superior to (2)6V AGM

One of the very important things to consider is the physical size of the batteries, particularly the height. Sometimes the 6V batteries are too tall for the battery box, so measure carefully and be aware of that.

Not a useful comparison
You can't use (3) 6's in an RV, you need two or four

Two sixes is still only 245 amp hrs at 12v
And two 12's will be from 160>210 amp hrs, depending group size and rating
Cheap grp 24 75 amp hrs each
Good grp27 110 amp hrs each

In many cases when going fla batteries, 6v GC give the best results,
Unless you are planning for heavy inverter loads,, then 12 AGM give better results

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