In the above video, BuzzFeed demonstrates how to find out if you have a fully-juiced AA battery: Rest the battery upright atop a table, pick it up with two fingers (not too far off the table) and then gently drop it. I decided to get my Galileo on and conduct a little in-office gravity experiment.  I took a brand new AA battery and a well-worn battery from a remote to one of the office TV monitors (the new battery is on the left, the old battery on the right):  I did simultaneous battery drops to see if, like the video said, the full battery would stand tall while the empty battery wobbled and fell over.