Infiniti G20 2000 Battery problem

I started driving my boyfriends 2000 Infiniti G20 and over the past few months the battery light and e-brake light will flash and eventually after a few days the car will just die, even if you're driving it. I've recently replaced the battery and the problem still happens. I've taken it to a repair shop and they can't find anything wrong. He suggested the daytime running lights might be draining the battery even when the car is off. So I've started to turn the lights completely off when turning off the car, but the problem still happens.

Anyone have any suggestions to what might be the problem?

hey i had a g20 and that would happen to me it was the alternator ....

Same thing here, I replaced the Altenator and everything was fine for 3mos but last week died while driving. Any ideas??