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Backup-MyBitLocker

This function will backup all BitLocker ExternalKeys (BEK), KeyPackages (KPG), and RecoveryPasswords (TXT) to a Directory (Path)
Backup-MyBitLockerKeys -Path F:\BitLocker\$(Get-MyBiosSerialNumber -Brief)
In the command above, I backed up everything to a Directory matching my BIOS Serial Number on my USB Drive

Multiple Paths

Supported.
Backup-MyBitLockerKeys -Path F:\BitLocker1, F:\BitLocker2