Yeah, my own insurance covered the courtesy van but my van is kitted out with all my kit and spare parts etc, it's a toolbox on wheels so working out anything else is a pita.
Ah!
If you've got to keep the show on the road in your current van then I guess @Skyliner33 might have a point. The system will show the battery has been disconnected but that could be explained as you removing it to charge it up.