I went through something similar a while back. My car died so I went to get a new battery because it was dead. The new battery died a day later, so we realized it was the alternator. Got that replaced and got the battery recharged. Then the battery died again...took it back to the mechanic and he says that somehow power isn't getting to the alternator. Turns out that my old battery cracked and leaked on everything under it. Got the wires replaced car ran fine(until the transmission blew)
~darp~
I'm probably no help but I can give you a few pics if you want me to show you.
