http://safetravel.dot.gov/whats_new_batteries.html

You can not check in lithium batteries but you can carry on.

That 4 UPS batteries would be a very hard sell as the larger batteries are limited to one installed plus two spares. http://safetravel.dot.gov/larger_batt.html Who knows, maybe they were considered normal or they didn't want to mess with you or this was more than five years ago

As for carrying three laptops, I have flown more than once with three, one as a gift for my family, two personal/work.