Report to Windows the status of an external battery system - typically when a computer is running off of a solar system
Originally I wanted to create a custom Windows battery driver so it would interface nicely.
Now I will be creating a custom app in Java with similar behaviour (% charge, time left of battery at current load levels.)
The hardware will be pretty simple, just a voltage divider to read the voltage with an arduino, and a current shunt (with an op-amp).
This will be transferred over serial over USB (bluetooth setup could be used for a laptop), into a Java application which will draw graphics to the screen in the system tray. Will look into making the code Windows and Linux / MacOS friendly. Will hopefully have some kind of cli interface.