Which battery box do you have? Has it set off metal detectors?
The one I have from SP is almost completely plastic and almost certainly would not set of any metal detectors.
My Core Sound battery box does seem to be mostly metal, and I've even taken it through some metal detectors with no problem, though I usually put it in the bin to go around, with my keys, phone and glasses. Very rarely I get asked what it is, and I say it's a cell phone charger battery, never had a problem.
You're almost certainly needlessly worrying. Just use what you have already.