Voltage drops to 3.6V after pad removal

[PeterK]

I've charged my OSTC 2 for the first time. Everything seemed to be normal, left it on the pad over night. It showed me on the screen 4.1V 99% but when I remove it from the pad it drops immediately to 3.6 V 60%, Is this normal behavior?

[jb2cool]

I’d keep it on charge till the display says 100% and goes green.