>>Using a large capacity batteries mean a longer charge time right?
Yeah, but I just plug it in overnight and that takes care of it.
>>Smaller capacity and size can reduce the weight, right?
Depending on the cell, yes.
>>Do you know the voltage of the batteries under load?
I would guess that it is close to 7.2 volts. I don't think the Epods draw that much current so the voltage probably drop too much.
>>Your Epod is permanently hacked? How "risky" is it to perfrom the permanent hack?
My original plan was to just have the 4500 mah battery "piggyback" the original via an exteranl jack, but my original epods battery is junk so now I am just using 4500. If I could buy the battery connectors somewhere I'd build a couple spare batteries...