Yea u are correct, the word alternator means that it alternates. Do it does go back and forth to battery

 

Well not quite....
Alternators are used in modern automobiles to charge the battery and to power the electrical system when its engine is running.

An alternator is an electromechanical device that converts mechanical energy to electrical energy in the form of alternating current.

http://en.wikipedia.org/wiki/Alternator....

The current flows from the Alt to the battery to keep it charged while running...
You do not alternate from where the power comes from... the battery & the Alt are connected together, and by design the power distribution for the entire car starts at the battery positive terminal...

Just FYI....
Mike

 

Cool, thanks, I understand now