For my project, I will have 3-9 198650's in a 3sXp relationship as a power source in conjunction with a wall wart 12V DC source. I would like to be able to install a switch, such as this one?, http://i00.i.aliimg.com/photo/v0/253934072/3_Way_rocker_switch.jpg
, to enable me to switch back and forth between the two power sources. My question is, how do I connect up the negative leads of the battery and the DC wall source?
Good 18650's are expensive, and I don't want to degrade them if I can help it, hence my concern. With this in mind, would it be a good idea to wire the negative leads of the wall wart and batteries together?
Thanks for tolerating a dumb question