you car gets its electricity from the alternator when it's running, although through the battery. chances are your alternator is dead. that would explain it. if that's the case, the small charge you put on the battery won't last long, because it's not getting charged up by the alternator, and is forced to use what little juice it has in reserve.
95 Eclipse RS - Sold and In Montana Now Project 95 GSX - In Full swing.