6 volt vs 12 volt batteries for boondocking

marcsbigfoot20b27 wrote:
Anyone have any feelings towards using say 3 of these batteries in parallel for boondocking?

Duracell AGM group 31 31DTMAGM

I have 1 as house batt and adding 2 more in parallel. Just installed 360 watts of solar. Converter is a WFCO 9855 3 stage.
Have a 2000 PSW inverter for microwave, Kurig, etc.

I do, firstly you want to get away from 12V batteries. the reason ?
LEAD.. not enough.. there are too many cells in a small space, so leave 12V for starting and the like.

Never parallel more than 1 set, you have no way to balance the currents and you will compromise lifespan.

Recommended best practices is to use 6,4 or 2V cells.
reason is that you can achieve better performance at lower cost
and have longer lifespan.


here is a table many won't like, but it's based on real world
recommendations that PE's like me use to size systems.

This is based on Panel Wattage and load ratings

0 to 600 watts = 12 Volts or higher
601 to 2000 watts = 24 volts or higher
2001 to 5000 watts = 48 volts or higher

so if you want to power a 4000W inverter, it's not going to be on 12 Volts. that's asking for a whole crock of trouble. voltage drop due to high current is your worst enemy here. and you don't have many volts to begin with.


looking at your apparent requirement of 300 Ah at 12V
you have 3 at $180 = $540 and probably 2 to 3 years max on one battery, you won't know which one until you disconnect the set and test them individually. PM me if you want a more technical explanation of why parallel is bad.

using 6V cells you will get much longer service and both cells will age at the same rate.