parallel batteries correction
If you have three 12V batteries:
1 x 75 Ah;
1 x 95 Ah;
1 x 130 Ah;
in parallel, they will act as one 12V unit of 300 Ah. No need to devide by 3.
In series, they could act as one 36V unit of 75Ah (smallest capacity) but only if you know what you are doing and are very careful in use. Not a practical setup.
If you must connect in series (to obtain higher voltage like 24V), then use identical batteries (manufacturer, model, and age) and connect them when they are flat. Then charge. Since discharging lead-acids to flat state costs you in battery life, you can use plan B: charge them separately fully, connect them briefly in parallel to further equalize the charge, and only then connect them in series. If the two batteries are identical it should be safe enough. Periodically you should check whether the voltage across all batteries is about the same.
I hope this helps someone.
bm.
Last edited by balsa model; 26th Jul 2007 at 18:39.