How To Test a AA battery, Easiest Way For Any Battery Fast, Easy!

[annunaki]

How To Test a AA battery, Easiest Way For Any Battery Fast, Easy!


http://www.youtube.com/watch?v=Y_m6p99l6ME

[conwaygolfer]

Wow - so simple and hopefully effective.

Thanks,
Conwaygolfer

[cwsmith]

Now that is cool!

I've been using batteries for decades and playing with radios and such for almost as long and I've never seen that.

Just goes to show, there's always something new to learn.

Thanks for the post,

CWS

[LCHIEN]

how many of you really believe this works?
just because they post it on the internet... must be true?
He says maybe it works because of the change in density. I say there's no mass lost* in a primary battery; no change in mass & no change in volume ==> No change in density.

* source: Wikipedia. if you look at the article on alkaline batteries at he section labeled chemistry, you will see from the chemical reaction that there's no outgassing, no water vapor, no material lost.

[gerti]

BTW it's kind of funny how originally it was the Duracell bunny, and then Energizer took over the bunny. In Europe Duracell is still marketed with the bunny. For a while I thought they had the same parent company, though apparently it's a bit more twisted:

http://en.wikipedia.org/wiki/Duracell_Bunny

[Stytooner]

I have not tried that. I did see something immediately that throws his result off.
All batteries are not created equal. Trying or testing things like this must be done with the exact same brand of battery off the same factory run preferably.

There can surely be different densities in different battery brands and models.
Different products can be used for wrapping. Different thickness material used for the poles etc....

Without doing his test correctly, I call bunk just for the obvious flaw in the visual presentation.

[capncarl]

I could see this working. When a battery is fresh and fully charged it is packed tight, as it chemically produces current it gasses off and causes the base of the can to slightly swell and create a "spring" effect on the flat base, allowing it to bounce more than the flat packed surface of the fresh cell.
Thats my story and I'm sticking to it. To test a 12 volt car battery you try to bounce in on the hood of the car.
capncarl

[woodturner]

He says maybe it works because of the change in density. I say there's no mass lost* in a primary battery; no change in mass & no change in volume ==> No change in density.

I suppose one could argue that as a battery is depleted, the energy is converted to mass (law of mass-energy conservation) but the change would be way too small to produce the effect he claims.

Still, it was on the internet, so it must be true. Next you will be telling me I can't open my car door with a potato . Silly scientists and engineers .

[ironhat]

... and I'm a French model!

[Stytooner]

Well, Bonejurr then.

[JimD]

I had two AA batteries at my desk, one that would not power the cordless mouse it is in and another from another mouse that is working fine. The "bad" battery bounces noticably more than the "good" battery. I think this test, while unusual, works. I suspect it is subtle bulging of the depleted battery that causes it to work but regardless of the reason, my little test validates this as a test method. It could be especially handy if you had 4 batteries in a device and wanted to know if all were bad.

On the other hand, at home I have a volt meter and that takes very little time too.

Jim

[cwsmith]

Well I certainly can't explain it; and I looked at the video with much doubt.

So, I grabbed my box of old batteries (I only mostly use AA Duracells and gave it a try on three different surfaces... MDF table top (RAS), the kitchen counter top (Formica), and a table in the library (pine).

The dead batteries bounced and fell over... although they didn't fall over everytime. (It depended on the height of the drop.) Of course even a brand new battery would fall over if it wasn't dropped straight.

I don't have any other size batteries other than AA around. All my AAA's are rechargeable.

But, I did try the drop at a few different heights up to about an inch... but at that height, they generally just fall over regardless. The curious thing was the "bounce" though... and dead batteries definitely bounced better than new batteries. Partially charged batteries also bounced, but not very well.

Interesting though, I think. I don't know why and I don't know if other brands have the same response to the drop.

CWS

[paultnl]

Looks like a job for Mythbusters

[annunaki]

Looks like a job for Mythbusters

Well if they're going to test it then I want to see it with car batteries !!

[JimD]

The batteries I used happened to be exactly the same as they have on the you tube. The fresh battery was an everready and the depleted battery a duracell. I needed to replace the depleted battery so I went to my admin and got a new duracell. It also falls over more readily than a fresh everready.

So be aware that while I think this works, the video is a bit mis-leading. Duracells in general fall over easier than at least one other make.

I still think this could be a discriminator if you didn't have enough fresh batteries and were trying to pick out the best one or two to go back with some fresh ones in a device needing more new batteries than you have. Otherwise I think it is just a curiosity. Without a "standard" of a fresh battery to check against I don't think the difference is so big that I would start throwing batteries away based upon a bounce test of a battery of unknown condition.

Jim