nanowinupdate

#Scan for available updates
$ci = New-CimInstance -Namespace root/Microsoft/Windows/WindowsUpdate -ClassName MSFT_WUOperationsSession  
$result = $ci | Invoke-CimMethod -MethodName ScanForUpdates -Arguments @{SearchCriteria="IsInstalled=0";OnlineScan=$true}
$result.Updates

#Install all available updates
$ci = New-CimInstance -Namespace root/Microsoft/Windows/WindowsUpdate -ClassName MSFT_WUOperationsSession
Invoke-CimMethod -InputObject $ci -MethodName ApplyApplicableUpdates
Restart-Computer; exit

#Get a list of installed updates
$ci = New-CimInstance -Namespace root/Microsoft/Windows/WindowsUpdate -ClassName MSFT_WUOperationsSession
$result = $ci | Invoke-CimMethod -MethodName ScanForUpdates -Arguments @{SearchCriteria="IsInstalled=1";OnlineScan=$true}
$result.Updates