What causes the battery to drain completely after a day or two usage.

What is your question?

Ref: 2001 Chevrolet Lumina The battery has been replaced 5 times with a new battery each time, from various retailers. The alternator has also been replaced with a new one. There are no lights or power is left on after usage. It initially starts well when a new battery is installed, but once its parked for a day or two, the battery requires to be jumped everyday afterwards.

What makes this problem better or worse?

It occurs after letting the car sit overnight. The alternator has been replaced to eliminate that as a potential problem.

How long has your 2001 Chevrolet Lumina had this problem?

About two month