Does the Battery Bounce Test actually work?

I heard that a good way to test if a battery is dead or alive is to see if it bounces. Supposedly, dead batteries bounce higher than living ones. Can someone tell me if this is a legitimate claim, and if it is, an explanation would be nice. 




Yes.
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The battery bounce test *kind of* works. You can tell whether the battery still has a charge greater than 90%, but bounce hight levels off at about 50% and doesn't go higher. This means that it is not clear whether the battery is completely discharged when you observe a bounce.


Why?
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[Steingart *et al.*](http://pubs.rsc.org/en/content/articlelanding/2015/ta/c5ta01576f#!divAbstract) just recently published a paper on the subject, and through scientific rigor could confirm this claim. The reason they give has to do with how an alkaline battery is built:


![Schematic cut through an alkaline battery.](https://i.stack.imgur.com/IY5wH.png)


([Source](http://en.wikipedia.org/wiki/File:Alkaline-battery-english.svg))


As you can see, a large part of the inside is devoted to the zinc anode. During the discharge, a redox reaction takes place to produce the current:
$$ \ce{Zn + 2MnO2 -> ZnO + Mn2O3} $$
The zinc (usually in some gel form at first) is slowly oxidized. As a result of this oxidization, crosslinks between the small zinc granules are formed, which make the whole center more rigid. As such, its "bounce" (or [*coefficient of restitution*](http://en.wikipedia.org/wiki/Coefficient_of_restitution)) becomes greater, because the downward kinetic energy cannot be fully absorbed by the gel anymore.


If you are interested in more details, check out the [article](http://pubs.rsc.org/en/content/articlelanding/2015/ta/c5ta01576f#!divAbstract) they published. If you don't have access you can read a summary given on the [Princeton University News](http://www.princeton.edu/main/news/archive/S42/72/95S25/index.xml?section=topstories) web page, where you also can see an animation of a series of discharged batteries bouncing to different heights.


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