When I shot this video, I was still trying to figure out
battery operation but I've since solved it
The PDF at my Github repo explains how I
used the original battery and charger
Instead of using a turnoff script, I now use systemd and a unit file to send a power-off command to the Teensy when a shutdown command is given from a terminal window or the GUI.
This procedure is described in the PDF at my Github repo.
 
