2011 FAA Transportation Regulations are as follows:
All batteries must be in carry-on luggage. Each traveler can have up to a 96wh lithium ion battery (8g of lithium content) connected to a device (camera, monitor, etc).
Travelers can also have up to 2 spare batteries that do not exceed 300wh(25g lithium content).
For example, having an XP-L90S connected to a camera, and carrying on an additional XP-L190Si, and XP-L90S(total is 280wh, or 23.3g lithium content).
