This sounds like the problem I had with my 2000 Impala, except mine would start again after about 5 - 10 minutes. The only indication when it would happen was the "Battery" on the message center.
After the Crankshaft Position Sensor was replaced, there has been no problems. That was3 years ago.
Good luck and I would definitely advise changing the crank sensor.
TakeSargeSarge
Tuesday, June 30th, 2009 AT 10:41 PM