I have a way to measure battery power

[DrD]

The teensy advantage might be your control over the resolution. In order to get anything more meaningful, you would need to get metrics on the actual battery... hence, the request "Please let us know it calculated values correlate with measured battery levels, especially at the 25% incremental points, as Cyrille posted..."

Otherwise, Cyrille has completely addressed the issue here, including your novel idea to pick apart the level points. There really isn't any earth-shaking point ... it is more a matter of something that could also be done, being done, and provides a hands on opportunity to learn more about the prime, etc.