Each Sony NPF style camcorder battery runs at 7.4V. By running them in series, it works at 14.8V which is the minimum power required for the 600 and 900 LED light panels at full brightness. I took two basic Sony NPF battery chargers, gutted them, and then wired them in Series to provide 14.8V DC.
Remove two screws under the rear sticker and then pry apart case
To wire up the cases for Series, basically you take the Negative wire from one and the Positive wire from the other and connect them to the barrel plug. The other two wires (negative and positive) from each charger would be connected together.
Sorry for poor diagram
Next I added a bit of extended wire and used my Barrel Plug (shown here) to connect directly to the LED light. The Barrel Connector is super easy to work with (no soldering), and is clearly marked with + and - for positive / negative placement. It's a very simple and cheap DIY to provide portable power for these large LED panels. If you want use heavier batteries, just make the wiring longer and mount to your light stand.
[Disclaimer] Attempt this DIY at your own risk. Using your batteries in other ways than intended may cause premature failure of your batteries, or damage.
Caleb over at DSLRVideoShooter.com, reviews one of the ePhoto 600 LED Video panels, and seems pretty happy with them. I agree that they could have done a better job with the power cords because if you have your lights fairly high, they are dangling at the barrel connector. I'm in the habit of tying my cables to the Yoke to prevent stress on the connector. I guess using batteries would solve that problem. [Thanks for the shot out Caleb]
I've got a 3pc set of the 900 LED panels, which I chose specifically because it has a bit more power than the 600s, but still has the battery mount option. They are also not too big so that I can pack them in a roller travel carry on luggage. If you have no plans for a battery mount, the 1200's will give you the most amount of power. I'll be honest to say I don't really have a proper bag, and these lights get bumped around quite a bit. They have been in constant use lately for the last few weeks and are still operating perfectly.
New in that lineup of LED panels is a '1200 Bi-Color' (color changing) version, but keep in mind that's only 600 LED's actually going full power in either Daylight or Tungsten temperatures. While they are back in stock, you can find them on Amazon available for Prime - Click Here.
Dimmable LED Video Light Panels
Don't forget that there are some bags available to make them easier to travel with. Not so much protection from dropping, but keeps the buttons, switches, and barndoors from getting snagged. Those baggies can be found on Amazon (click here).