I want to expand my agm backup system, and can get 6v 12ah cells new for 10x for $45 shipped.
Is it possible, to use mosfets on pwm outputs to switch between batteys (1x 12v 18ah agm, 5x (2x 6v parallel 12ah wired in series), and a single pwm charger (morningstar sg-4 @ 15v 2a powered from ac/dc wall adaper (or ww, wallwart).
IE, (x amount of time, switch to next battery, etc), later adding battery voltage sensors to make it smat as to what cells need to be charged/equalized the most and thus get more charging time.
Jus an idea rahter than messing around with a large bank and a ton of chargers, or parallel/series wiring of banks. Just mosfet switch the charger to batterys on a timer, or using voltage analog input sensors from each cell bank (2x 6v 12ah, and sngle 12v 18ah) to determine which needs a charge more.
Any thoughts?