How to solve power, battery icon missing from taskbar

This solved it for me:

https://www.computerhope.com/issues/ch001560.htm

Steps:

Scan for hardware changes

1. Open the Windows Device Manager.
2. Click the Action menu at the top of the Device Manager window and select Scan for hardware changes.
3. Expand the Batteries section in the Device Manager.
4. Verify the Microsoft AC Adapter and Microsoft ACPI-Compliant Control Method Battery devices are displayed.
5. Check the notification area on the Taskbar and see if the battery icon is now visible.
6. If the battery icon is still greyed out, proceed to the next section.

Disable and Re-enable Microsoft Drivers

1. Open the Windows Device Manager.
2. Expand the Batteries section.
3. Right-click on the Microsoft AC Adapter and Microsoft ACPI-Compliant Control Method Batterydevices and select the Disableoption.
4. Right-click on the two devices again and select Enable.
5. Restart the laptop and see if the battery icon is now visible in the notification area on the taskbar.