Here's what I have from a recent backup file I had on hand at home. It came from the system.AFD file
BATVOLTS.MAX, 90
BATVOLTS.RED_HIGH, 90
BATVOLTS.YELLOW_HIGH, 78
BATVOLTS.YELLOW_LOW, 70
BATVOLTS.RED_LOW, 68
BATVOLTS.MIN, 67
BATVOLTS.ENABLE, 1
BATVOLTS.AUDIO, 1
While I was at the airport two days ago, the EFIS did remain on after I shut off the master, and it did show the red bar on the bottom counting down to shut-off. The voltage when on battery power was still showing 2.6 volts, but it remained on until the timer ran out.