In case you missed it, there's a new US Department of Transportation rule regarding the number of lithium grams you can bring onto an airplane in your rechargeable batteries. As Xantrex's PowerSource Mobile 100 proves, there's one little problem: there's no way to tell how much lithium is inside of a lithium-based battery. From the Consumer Electronics Show in Las Vegas, TechWebTV's David Berlind uncovers the poorly thought out policy.