That was the most I've ever had, but I always have 50 or so in my bag when traveling on business. I've never been told that they were a problem or that I shouldn't take them on the plane. Security always knows about the batteries because my bags get have searched pretty much every trip thanks to a bag full of lights. My only real worry is taking a light that has been on a gun since they swab for residue of bomb materials. I don't know if that would flag the sensor, but I'd rather not find out.
