Sort of. But you will have to do some scripting.
You can use the command line tool calibredb to export all the books, using some save template.
With some effort I suspect that it would even be possible to list books updated since last time, and only export those. And it would even be possible to run this script every time you exit calibre.
More information in the fine manual:
http://manual.calibre-ebook.com/cli/...libredb-export
I do something similar, but mostly manually. I save the books in my calibre library to a shared folder on my NAS, and use an app to sync my device to that folder over wifi. After that I have all the books stored on my device. The sync app is run automatically every hour if I charge my tablet.