If you wish to hide the battery indicator in the task bar on some devices, you can set: HKLM\Services\Power\ShowIcon = 0 (DWORD decimal) And to show: HKLM\Services\Power\ShowIcon = 1 (DWORD decimal)
Note that this icon and its feature may not be available on your device at all. For example, the HTC Wizard regularly ships with a battery indicator in the Tray instead, governed by "Windows\Startup\Init_Tray.exe".