Semi-related. I bought a Anker Astro usb battery for my Edirol R09HR. 5600 mah.
Coupled with one of Ted's usb/dc cables, I got over 12 hours and 20 minutes before the battery finally drained.
http://www.amazon.com/5600mAh-Portable-External-Battery-Smartphones/dp/B005K7192GI highly recommend Anker for the Edirol R09HR. Ths size and run times are perfect.
EDIT: Swapped out my PNY 16GB card for a Centon 16GB card and
got 15 + hours of run time. Tested it twice to confirm. For some reason, the Centon draws less power when writing than the PNY. Centon is sold at Tigerdirect