> never having heard not to put a battery in checked luggage
Maybe not conventional batteries, but you've been disallowed from putting lithium batteries in checked luggage for at least 16 years. I remember being dragged into the bowels of an airport by security to open my checked bag because I'd forgotten a device in it. That was in 2009.
When you check in bags they ask you to make sure there aren't any rechargeable devices or battery packs in them and this has also been going on for a long time.
Maybe not conventional batteries, but you've been disallowed from putting lithium batteries in checked luggage for at least 16 years. I remember being dragged into the bowels of an airport by security to open my checked bag because I'd forgotten a device in it. That was in 2009.
When you check in bags they ask you to make sure there aren't any rechargeable devices or battery packs in them and this has also been going on for a long time.