shutdown -f now, thinking it will do a full power off sequence.
Instead, it ends with
*Checking battery state...
and just hangs there.
Should I add
-h switch to fully take power off, or is there some other problem?
You're supposed to run
This doesn't preclude another issue which would cause
Could be an ACPI issue. Look if your distro provides an ACPI package for your brand of laptop.
It's possible this message could also come from a script executing at shutdown. Find out how your distro handles shutdown scripts and you might be able to edit that particular script to not check battery state on shutdown.