Hi, I a making a data capture device with a Nano. The data capture sensor is 5vdc at tiny tiny mA, my meter does not even show current drain. I would like to battery power this but space is limited but I can fit 6 x AA batteries in nooks and crannies then wire them all in series.
I would then use a small buck converter to provide the 5vdc from the batteries. I'd like to use Li-Ion, but then I think I need a balance-charger and there's no room for that. So, Ni-Mh is the next choice.
Finally the question: If I solder the Ni-Mh batteries in series, can I just charge them at 9v x 100mA or whatever is needed?