Let's tally the results.

Pass: You checked local rules for every city on your itinerary, and you're clear. Your vape is in your carry-on with the battery protected, and your airline's policy allows it.

Fail: You didn't check local rules, your vape is in your checked bag, or your battery is loose in your pocket. If any of these apply, fix them before you head to the airport.

A fail isn't the end of the world—you can usually correct it. But it might mean missing your flight or losing your device. Nobody wants that.