I would save the recovery key on a USB stick or the numeric password into a password manager in addition to Account if I were you. I in fact do both. If you do not want unencrypted recovery material to ever be on an unencrypted USB storage, you can see the numeric password using elevated command line and copy it from there:
C:\> manage-bde -protectors -get C:
. . . .
Numerical password:
ID: {1234CDEF-xxxx-xxxx-xxxx-xxxxxxxxxxxxx}
Password:
NNNNNN-....-NNNNNN
The first 8 of the ID, 1234CDEF in this example, is the same number as the Key ID on the Account website, and NNNNNN-....-NNNNNN is the 48-digit unlock password. Copy both from console into your password manager secure note or something, repeat for every encrypted drive letter, and then close command prompt window.
A recovery key is saved to USB stick as a hidden system file with the .BEK extension (the above command will display its name as "External key"). Use 'X:\> attrib -H -S *.BEK' in a command prompt on the USB drive (X: here) root to make them visible if you want. You can have as many saved on the same drive, they have GUID names, and Windows will pick the one it needs to decrypt a drive (the key protector GUID is stored unencrypted). The numeric password is saved as a normal text file.
For an ultimate security, a keypad-secured USB stick from a reputable vendor goes a long way. Whether you need one is your call based on the value of the BitLocker-encrypted data to the malicious party.