Originally posted by sausage_link
well 2 are 16 volts and the others are 25 volts
ill see if i gots some 10 volt ones
Go for the 16V ones. Consider that when you charge a battery it peaks between 9 and 10 (more if they're old!) volts. Also gives you some leeway if you decide to muck around with 7 cells
BTW they make a nice mess when they explode!