I created a guest account and found the icon on the panel when I logged in as guest. A bit of guessing located the problem to my dconf database and using gsettings to locate any power/battery-related settings pointed me to
org.gnome.settings-daemon.plugins.power
which had been deactivated. Clicking 'Active' and restarting gnome-shell solved my problem.
]]>What I've tried:
* Disabling all extensions (a lot of posts about the system monitor extension causing this -- I've never used it). Extension turn off registers but still no battery.
* Checking htop and gnome power statistics to see if the system knows about my battery. Both report in detail about the battery.
* Checking /usr/share/gnome-shell/js/ui/panel.js to see if the power applet had been excluded somehow. Nope, it's listed.
* Checking dconf to see if I could find some setting there. Ubuntu user posts led me to org.gnome.power-manager but unlike those users I found no setting relevant ("icon-policy")
* Checking gnome settings and tweak settings. Found nothing that seemed relevant.
A lot of posts about this pops up around gnome 3.2 which apparently had a bug with this problem. I'm not sure what version gnome-shell was before the update but currently it is 3.6.3 and the laptop has been rebooted and had gnome-shell restarted any number of times since then.
Any suggestions?
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