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I am reading the book "Make: Electronics" by Charles Platt. It follows a fun and very effective approach about learning by doing. Along the way (pretty much at the beginning actually) it invites the reader to short an alkaline 1.5 V AA battery. This has been asked here as well, and answered properly: https://physics.stackexchange.com/questions/30594/short-circuit-an-alkaline-battery.

The book clearly recommends NOT to use any rechargeable batteries for that experiment, by stressing that several times. Lithium batteries, particularly, could explode, but any other rechargeable batteries are dangerous as well.

What it is missing is any word about Zinc-Carbon. Those are not rechargeable, so they do not fall in the category of never-do-it. But they are not explicitly the recommended kind. So, I am really curious about what to expect. Thank you very much!

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I chose to go ahead and give it a try.

Result: The battery got hot to the point that I could not keep it in my hand for more than a few seconds, but not so much to melt the case.

Voltage dropped to 0.1 in about ten minutes, and that was the point where the temperature was at its highest.

The wires did not get as warm as I expected, probably because their resistance is negligible compared with the internal battery one.

Unfortunately I did not have a digital thermometer, so all of this test was very rough. A graph comparing temperature raise and voltage drop over time would have been cool. After dropping below 0.1V, voltage kept dropping, while temperature dropped as well - battery got less warm.

So to answer my own question: it was safe, at least in my case.

The author of the book, for what matter alkaline batteries, recommends wearing protective glasses (and I would add, gloves) just in case the battery is defective, so I advise to do the same in case you want to reproduce this.

If you do, and have more accurate measurement instruments (and patience) than I had, it would be interesting to see the behavior pictured (and compared with a test with an alkaline cell.)

By the way, in the minutes I took to write this the battery is still providing current into the short circuit. It is at 45mV right now.

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  • \$\begingroup\$ By the way, after 30 more minutes that battery is still short-circuited and is still providing 19 mA. It is (of course) much colder now, just a bit over room temperature. \$\endgroup\$
    – Dakatine
    Sep 4, 2013 at 16:31
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    \$\begingroup\$ This is interesting. I am now trying with a second new Zinc-Carbon battery and I am reading current (by protecting the ammeter with a fuse). Surprisingly, I am reading 0,8A with the fuse in the circuit. I then removed the fused and the meter read 2.7A. This leads me to think that: 1) Zinc-Carbon deliver far less current than a Alkaline one, according to the answer to the question I mentioned 2) A fuse also acts as a resistor and quite a significative one. \$\endgroup\$
    – Dakatine
    Sep 6, 2013 at 14:11
  • \$\begingroup\$ This also leads me to think that this 500mA fuse sucks since it took 800mA without melting. It got darker, it bent, but it still allows current to pass through. \$\endgroup\$
    – Dakatine
    Sep 6, 2013 at 14:16
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    \$\begingroup\$ Fuses are rated by their pass current, not their blow current. A 500mA fuse can easily take 1.5A before blowing. \$\endgroup\$ Sep 7, 2013 at 14:01

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