How to enable battery status indicator in gnome shell?

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http://askubuntu.com – I'm using Ubuntu Precise with Gnome Shell on a Dell Latitude E6520 and I'm missing the battery status icon. When I run gnome-power-statistics then the battery info is displayed correctly so I'm sure Linux and Gnome can see the battery (So there is no ACPI problem). But there simply is no indicator icon in the gnome shell menu bar. In the Power settings the combo box Show battery status in the menu bar is always empty. I can choose between the values When battery is present, When battery is charging/in use and never but it doesn't matter what I select here, the icon never appears and when I e (HowTos)