People were pretty excited when the Dark Forces Team successfully ported WP7 over to the HD2, but it wasn't without its bugs. One of the more annoying of them was that the battery level indicator was inaccurate. Tired of the lies, XDA member, arkatis, decided to do something about it. He has posted a registry hack that seems to resolve the issue. Here's the quick and dirty on how to do it:
1) Charge your phone until the green light shows up
2) Unplug it from A/C and open registry editor
3) Go to the reg path
4) Edit the value from 6 to 20…press ok..Now you will see the battery indicator level has been changed! Again go and edit the value and from 20 go to 80..press ok! Restart and enjoy!
If you want to read the full post with feedback, you can check it out here.