How low can the Tesla battery go?

While not really on purpose, I had the opportunity tonight to run the Tesla down to 3% tonight (9 miles of range). The alerts in both the Nav system and the energy console were helpful. Was very happy to see the battery drain at the predicted rate in the Nav screen (taking your destination into account along with your average driving and the coming terrain / elevation). I did notice that it was very accurate on the last drive back from Las Vegas - much more so than before the v6.1 update. 

Now if I could just get the battery in my iPhone and Mac to behave the same at single digit percentages of remaining life....