I recently purchased another K2 Energy K2B12V10EB battery (4 cells in series, 10AH, 123 Watt-hour LiFePO4 chemistry – in a package similar to a 7AH SLA battery but about 1/3 the weight).
I noted with interest that the package had a very large red warning label that read “Primary Lithium Batteries — Forbidden for transport aboard passenger aircraft”.
Concerned that might prevent me from traveling by air with my radio and battery; I found and read a government document that describes the situation. In summary it seems that carrying such a battery in your carry-on bag is OK, but you are not allowed to pack it with equipment in your checked bag. I’m no lawyer, your mileage may vary, etc., but here’s the document:
http://safetravel.dot.gov/whats_new_batteries.html
LiFePO4 Battery (12V, 10AH, 2.5Lbs)
