Wouldn’t expect the bar itself to get hot; just the battery. The bar will be very low resistance and therefore only a tiny portion of the total heat will end up in it.
Now, if you stuck one terminal to one piercing and another terminal to another piercing, then you might have a bad time…
0ops@piefed.zip 3 days ago
Can confirm, I used to be a professional idiot-kid who liked playing with batteries and paperclips