Battery draining over night

[AC Question]

"Always on display" used up 30% of charge overnight(10 hours). Is this normal?

 

[belodion]

30% of the charge used, or 30% of the total battery charge?
In the first case, if say 5% of the total battery charge was used, 30% of that would be 1.5% of the total charge, which would be okay.