Max current draw when charging at 240v appears to be 15a

The two main benefits of the high voltage are less voltage drop over distance and less heat generated due to huge reductions in current for the same power. Our 900 HP 4,160V air compressor where I used to work used about the same sized motor leads as our other 100 HP 480V motors.

 

^ either:
(*) less heat and voltage drop for the same wire, or
(*) smaller cheaper wire for the same heat and %-voltage drop, or
(*) any tradeoff choice in between.

 

I think that the bottom line is that it is easy to measure how much power is coming out of the wall into the car, but measuring how much is actually going into the battery is more difficult. Not impossible, but you have to use the right tools.