Choice of Batteries - Which Would You Choose?

pnichols wrote:

beemerphile1 wrote:
Is there really any advantage to 6v AGM over 12v AGM?

Flooded 6v are more robust than most flooded 12v but I doubt there is much advantage to 6v AGM.

An outstanding question in your first sentence that I've asked a few times and never received an answer to.

With respect to the "thicker plate" argument when comparing 6V flooded deep cycle batteries to (true) 12V flooded deep cycle batteries:

For batteries of equivalent capacity and cycle life, 6V cells have to carry twice the current of 12V cells - and since plate destruction/erosion over time has a lot to do (but I don't know how much) with amount of current flow over time - 6V battery plates had better be thicker than 12V plates in order to last as long as the 12V plates. For equivalent batteries, I suspect that quality 6V deep cycle plates should be about twice as thick as quality 12V deep cycle plates.

All IMHO, of course.

I wouldn't be surprised if the thickness of the absorbent glass mat is the governing factor. Perhaps there is a magic ratio of mat v.s. lead thickness.

I have looked at the 6/12 data for AGMs and IIRC, there was only a slight difference either way within brands. I would guess there is little variance in plate thickness.

HTH;
John