No, the point of the 5th is that you cannot be compelled to give testimony against yourself (which is under oath and for which you will go to jail if you perjure yourself.) You are not protected from helping to convict yourself if you leave the evidence of your crimes available to the court. An encrypted drive is being considered as something like an un-crackable safe for which you have the combination; providing the password is not testifying, it is providing the court access to evidence that you would otherwise be concealing from a valid warrant.