Traian,
I was not "guessing" when I gave my recommendation to ship our ECL batteries via UPS or FedEx. I, like many others on this forum, have read all the TSA data before. I have traveled on the airlines more than a few times, both at the little pointy end and back in the tube on business.
The 1st thing we must realize is that the TSA is not the enemy. They have an extremely difficult job. They have to try and find a needle in a haystack 24/7. Their default mode when they are not sure is always to lean toward "NO, it can't go on the plane". And for the safety of all of us I am glad they are there trying to do the best they can with limited resources and dealing with an ever changing set of technologies thrown at them.
You have to be very careful when you read the TSA information. This information is directed at normal consumer battery use. Our batteries, both in type and in their configuration, are a very rare exception for the TSA official inspecting them. We are a one in a million case, NOT a common battery problem. The latest FAA SAFO is dated 6/2009. It does not even mention Lithium POLYMER Batteries. It only addresses Lithium ION Batteries and Lithium METAL Batteries (AKA Primary Batteries). This is because at this time there were NO Li Poly batteries being used by any consumer devices. This means that ALL the TSA info. is referring ONLY to these two battery types, NOT our LiPos. This is why the term "most" is used in this info. The TSA knows that there are other battery types out there (like ours) and they were only addressing the two types that covers 99.9% of all batteries taken on planes.
There is a HUGE difference between our Li Po batteries and Li Ion batteries when it comes to safety on a plane. Now that computer mfg. are starting to use LiPos in some of their smaller computers the TSA will have to address this issue soon. As of now our batteries are in a gray area for the TSA. If the TSA person you are dealing with is not sure what to do, then they will most likely use the "metal battery, primary" rules for your ECL battery. This would mean A TOTAL OF 2 GRAMS OF LITHIUM allowed. this is about 25 watt/hrs. (less than 1/2 of one of our batteries).
I could go on and on with more details about this but I think most people get it and will just ship it. ...... 90% of the time: IF YOU CARRY THEM ON THE PLANE: "YOU WILL BE PULLED ASIDE FOR A FULL BAG CHECK AND DISCUSSION". If you want to argue the fine points of the TSA Battery rules with a government official who is already, for your safety, leaning toward NO, .... then be my guest. But please don't recommend that other people fight this battle based on a lack of a complete understanding of all the facts.
Please remember, if the TSA person says NO then this means your contest trip is going to be a lot less than fun. I like to travel as smoothly as possible and know that I have done everything in my power to eliminate potential problems. ..... Of course, your milage may vary.