I have no idea how my S7 Edge is doing this, I've had it since the day they came out and I just got 8 hours of screen time for the first time ever. I've been seeing 5 hours a day for awhile now but this is insane.
Just browsing around, I would lose about 1% per 2 minutes...
Yikes... But I jost got it so no problem, go over to BlackBerry support
and download the images to the latest firmware.
I fresh install 6.0.1 and now I get about 1% per 5-6 minutes of heavy browsing
and it literally only took 3% from 11PM to 8:30AM of standby.
It could standby for probably 7 days