12volt 6 volt(12)

[bmm32005]

Is there a advantage or disadvantage and what is the difference between say a 100 amp 12 volt battery and say a 100 amp 2- 6 volt batteries?

[noelex 77]

Usually 6v batteries are better deep cycle batteries than the equivalent 12v batteries (2v cells are often better again) from the same manufacturer.

You need 2x 100AHr 6v batteries to make a 12v 100Ahr battery bank.

[Vasco]

From a non electrical viewpoint, the 6 volts are lighter and easier to lug around, especially if the bank is in some god forsaken hole in the boat.

[denverd0n]

To elaborate on Vasco's answer... Roughly speaking, a 6 volt, 200 a/h battery will weigh neighborhood of half what a 12 volt, 200 a/h battery will weigh. Hence, for large banks, it is easier to move around a number of 6 volt batteries than it is to move around the equivalent a/h in 12 volt batteries.

The other issue is that in the U.S., 6 volt deep cycle batteries are used for golf carts. As such, it is easy to find relatively inexpensive, high capacity, 6 volt batteries that are truly made for serious deep cycle use.

[Thin Line]

If you look at the rating for almost every 12v battery on the shelf you'll see an average of 300 cycles, 6v batteries are normally more than twice that number. The 215ah 6v Deka are rated at 700 cycles to 50% and the tall 370ah 6v 8L16 are rated to 1000 cycles! Heavier plates, more lead and a lot longer life are the reason I have 6v. My old boat I installed the big 370ah batteries, not a single complaint here!

The new boat has a bank consisting of 8 6v's for a total of 860ah