Has anyone found a place where one can test the actual voltage on the Prodigy battery. I would like to test the voltage against the display to verify that I am truly charging between 50 and 80 percent by voltage. The Prodigy display does give the percentage and there is also a bar graph but from what is written these kind of readouts are notoriously incorrect. I just want to verify for a benchmark on my display that corresponds with voltage so I know when to charge and when to stop by the display without having to have a volt meter connected while charging..