9V Battery Discharge Experiment

During a break on working on my Ludum Dare 30 entry (which I’ll post about a bit later), I conducted this little experiment:

You might want to watch it in HD on Youtube. The changes are subtle!

It’s a timelapse through a macro lens of a 9V battery (with the outer skin removed) being discharged for 20-25 minutes or so. I’d have liked to run it longer but my camera ran out of power! I discharged it the rest of the way off-camera and it looks rather dramatically different from a new one.

Note that only cheap, generic 9V batteries look like this on the inside! Brand-name batteries tend to be constructed of a set of 6 roughly AAAA-sized cylindrical cells. Which is kind of neat in its own right, but doesn’t give you a nifty view of what’s going on inside like these cheap ones do. 🙂