If they ask the dumb question of what you use a flashlight for, answer them politely and restrain from sarcasm. And use brightnorm's idea of info sheets for your lights. Also, before you enter the airport, take a moment to open up the light and air out that lithium odor. If they smell it when inspecting a light they may have questions. Your spares should be placed in a small bag and secured with a rubberband or tape. You wouldn't want them shorting out. Consider putting them in checked baggage.
Don't risk setting off the walk thru detector by carrying something metal on you, even something small, since it may make them suspicious and submit you to closer scrutiny when they pull you aside. Don't give them the chance. When I fly, I put all objects that might set of the walk-thru detector in a ziploc bag inside my carry-on. I even put my belt and watch in there. That seems to be better and more efficient than putting your stuff in the basket. If they ask to see something, they don't have to go through my whole bag, just look through the ziploc. Chances are though that they won't even ask.
I've started carrying the TSA list of permitted and banned items in case they try to talk me into surrendering a permitted item they claim is not. If they insist, I would politely ask to speak to a supervisor. Be sure to allow a little extra time before your flight so you don't have to choose between missing your flight or giving up your gear.
Bottom line, make it as easy and non-threatening as you can for them. They may be a little jumpy as it is. Put their mind at ease and cooperate. But stand your ground when you know your right.
In some counties, though, I wouldn't take anything for granted. Probably every item is open to interpretation. (Escuse me sir, did you really think you could take that wristwatch on the plane?)
And as for the confiscated AAA, that guard definitely took it for himself. Bummer. /ubbthreads/images/graemlins/frown.gif