Canon imageFORMULA P-208II Personal Document Scanner, 1.5" x 12.3" x 2.2"

Q: Is this battery-operated?

No, it is not battery powered. It is plugged into the computer by USB cable and powered by that connection. You can order a longer USB cable (we use 6' or 10') to place it farther away from your computer but it does come with a USB cable.PS - the optional wireless/battery unit is:Canon WU10 Wireless Adapter and Battery Pack for P-Series Mobile Document Scannerhttp://www.amazon.com/Canon-WU10-Wireless-P-Series-Document/dp/B00A6GHBMI

Q: Does this scan duplex?

If you are referring to scanning both sides of a document, then yes it does scan duplex. And to my surprise this device does a fantastic job with the quality of scanning.