Since it's being discussed again, here's some pics of the popular eBay Power Bank battery
mounted under my 70D with blu-tack. The battery cable is a cheapo off eBay also, just like this one
. You want to look for a "left angle" on the miniUSB end for the cable to go this way. XLR cables are custom "blacked out" GAKables.
I've mentioned this before in some other thread - the battery is not really 20,000 mAh. From the item description:
High capacity: 20000mAh.
Note:nominal capacity: 20000mAh, battery, actual capacity: 12000-18000mAh
Not that it really matters in practice, though. Mine runs for at least 10 hours powering 4 mics, and after that it still shows 50% capacity (if the indicators are to be trusted, which they're not).
As for rechargeable AAs, I use the Duracell Ion Core in my FP24. They are re-branded Eneloop XX's
but sell for much less where I am. My local grocery store stocks them.