If you mean keep appending output to a CSV file, the export-csv cmdlet doesn't directly support this, however you could use the convertto-csv cmdlt and remove the header row as follows:

get-psdrive | export-csv ./psdrives.csv -NoTypeInformation

get-psdrive | ConvertTo-Csv -NoTypeInformation |

foreach {$start=$true} {if ($start) {$start=$false} else {$_}} |

Out-File .\psdrives.csv -Append -Encoding ASCII

The code snippet above is based on a more complete solution described by Dmitry Sotnikov:

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