6v series vs. 12v parallel

RoyB wrote:
Personally I would rather have 12VDC batteries in parallel just for the possible rare occasion I have a 6VDC battery failure which would put me dead in the water...

If you plan on running your batteries into the ground before replacement, then 12v is a better choice because one will surely fail first. Catastrophic premature battery failure is extremely unlikely.

You will sacrifice AH capacity for that choice however.

You can get more bank for the bucks up to a point. Thanks to the golf cart world you can find 6vdc 220AH batteries fro around $70-$80 each. Of course you will need two of these 220AH batteries in series to give the 12VDC you need for the trailer. Two 6V 220AH batteries in series will give you 12VDC at 220AHs capacity for $140-$160... Try buying two 12VDC 110Ah Batteries to connect in parallel to give you the 220Ahs capacity for #140 - $160...

You also will see the two 6vDC batteries will weigh more then the two 12VDC batteries which means they will have larger cores inside. This almost directly gives you more RESERVE POWER to use time wise...

That was the way I justified it in my mind...

Personally I would rather have 12VDC batteries in parallel just for the possible rare occasion I have a 6VDC battery failure which would put me dead in the water...

Roy Ken

Misleading to compare GC2 and 8D :R

wnjj wrote:
A typical group 27 12V battery is around 100 Ah and the 6V of similar size is more than 200. So usually you gain a little going to 6V.

x2

The 12v example above is true, but misleading. You are not likely to find a 12v battery (that you can lift) of much over 100ah.

While the article is correct about series and parallel amp-hours, the examples they used are not even close.

A typical group 27 12V battery is around 100 Ah and the 6V of similar size is more than 200. So usually you gain a little going to 6V.

I think the reason golf carts prefer 6V is because the same case only has 3 (2V) cells and therefore the plates are thicker and more rugged.