This function returns the number of levels the battery driver can return.
LONG WINAPI BatteryDrvrGetLevels ( void );
This function always returns 0x00020002, indicating two levels for the main battery and two levels for the backup battery.
The return value gives the number of levels that the driver is capable of returning in the BatteryFlag and BackupBatteryFlag members of the BATTERY_STATUS structure, as used by the BatteryDrvrGetStatus function.