If I make the Hotspot (by train, for example), I plug it into the computer. Also by car it is still connected. In my case, the battery is not a real concern (not games but pictures, and video playback)
Note that it was delivered in JB (penultimate) and has been updated to start up and if the battery is removable ... I do not know where to buy one Replacement!
For the rest, say 1) that AcerCloud, cloud according ACER not fire my enthusiasm (It takes PC> Windows = 7) 2) and that I have put a lot of apps (including a reading light) but everything remains fluid.
Summary: excellent value for money for an experienced user, demanding but not geek.