The link to the .pdf says a lot in that as far as the FAA and US DOT are concerned, the batteries can be brought aboard as carry-on, and checked in certain instances. However, if you read at the top, it says "Based on US DOT regulations (49 CFR, Sec. 175.10). TSA security, individual airline, and international rules may, at times, be more restrictive". So TSA, the airline, and international rules dictate what can be done, NOT the FAA. I would expect TSA interpretation to change depending on the terrorist level, and the other two opinions can change on a whim. In other words, we all roll the dice and take our chances. I would hope though that a copy of the .pdf guidance would be good ammunition in any discussion. I'm facing this same thing in November, so it is of great interest.