Airline email said 'may be restricted'. Anyone had their batteries denied? How many, what type? Is 'onboard' carry-on, checked or both? Are batteries detected at security or does the airline ask? I'm hoping or thinking the warning to passengers is mostly about legally covering their asses. Obviously, it's going to vary by airline. I have a flight tomorrow. I want to take 7 batteries. Ultrabook - unremovable battery of unknown type. Six Lithium-Ion: EM5 and PL1 - 2 each, Smartphone - 2.