"Dead" battery bounce effect.
For years I've mentioned to my physics students that hydrogen gas bubbles increase the internal resistance of simple batteries as they are used. I've also mentioned that dropping a battery helps dislodge some of that hydrogen buildup and perhaps giving a little extra life to the battery (particularly in low current draw applications like a TV remote control). Pretty much all of us have experienced this when the remote doesn't respond until we give it a rough shake.
Well, I did not know of the battery bounce test until told of it by a physics student. Apparently bad batteries bounce (I'm thinking because of the hydrogen build up but this article suggests otherwise).http://lifehacker.com/test-if-your-batteries-are-dead-by-dropping-them-on-a-h-1630525062
Thanks to student +Alex Brnjac
for suggesting I check this out. You may find it interesting as well.