Find out if that disposable battery’s dead without any extra gear (and learn why it works)
posted Thursday, October 2, 2014 at 2:52 PM EDT
Have you got a dozen disposable AA batteries knocking around at the bottom of your camera bag, and you're not quite sure if they've got any life remaining? It's a situation we too have found ourselves in before now, and it tends to self-perpetuate. You leave them in there, intending to check them when you get home, but you never quite get around to remembering to do so. In the meantime, more disposables get opened, used for a while in a flash strobe or other high-drain piece of gear, and then added to the pile of batteries that probably still have some more use left in them.
It turns out, there's a remarkably easy way to test these cells and decide whether you should just throw them away now. Among the masses of gear required, you'll need a battery to test, and a smooth, hard surface to test it on. OK, not quite masses of gear -- this is about as simple and elegant as you can get. All you do is drop the cell on its end from a short distance, and see whether it bounces.
If there's a significant bounce, the cell is dead and can be disposed of. If it doesn't bounce, there's life left and it's worth hanging onto. But why does this trick work? (And work it does, even though it sounds like it shouldn't.) There is, not surprisingly, a fairly simple explanation -- but proving the theory was a bit more complex.
Thankfully, somebody else has already done the grunt work, as you'll see in the video above. So now, you not only have a quick and easy way to test your batteries, your curiosity is already satisfied as well. All thanks to Lee Hite, a member of the Cincinnati East branch of the Romeo Club, who decided to get to the bottom of the mystery after it became a talking point at a club luncheon. Thanks, Lee!