This thread seems to be essentially all wrong.
"What does this do to its edibility once the energy has been all used up? "
The energy used to run the clock doesn't came from the potato. It comes from the coal used to smelt the zinc from its ore.
"Not sure how it will taste, but it will reduce the ascorbic acid content."
Probably true, but not a big deal
"Potatoes have a higher content of vitamin C than even oranges do."
Not true
http://en.wikipedia.org/wiki/Vitamin_C#Plant_sources
"You will also get some metal ions in your potato.
Copper ions, zinc ions, etc, depending on what your electrodes are."
Not quite true, there's no "probably" about it. The energy is released by the conversion of metallic zinc to zinc ions.
"Perhaps some organometallic compounds."
I doubt it; most organozinc compounds are not stable in the presence of air or water.
"Some of the metal ions may in fact be vitamins"
No, they may be minerals which the body uses, but they can't be vitamins since ther are not organic compounds.
https://www.thenakedscientists.com/forum/index.php?topic=474...
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Is a potato used as a battery still edible?
This thread seems to be essentially all wrong. "What does this do to its edibility once the energy has been all used up? " The energy used to run the clock doesn't came from the potato. It comes from the coal used to smelt the zinc from its ore. "Not sure how it will taste, but it will reduce the ascorbic acid content." Probably true, but not a big deal "Potatoes have a higher content of vitamin C than even oranges do." Not true http://en.wikipedia.org/wiki/Vitamin_C#Plant_sources
"You will also get some metal ions in your potato. Copper ions, zinc ions, etc, depending on what your electrodes are." Not quite true, there's no "probably" about it. The energy is released by the conversion of metallic zinc to zinc ions.
"Perhaps some organometallic compounds." I doubt it; most organozinc compounds are not stable in the presence of air or water.
"Some of the metal ions may in fact be vitamins" No, they may be minerals which the body uses, but they can't be vitamins since ther are not organic compounds.
Nobody has mentioned the fact that spuds exposed to light generate toxic chemicals http://en.wikipedia.org/wiki/Solanine#Solanine_in_potatoes
The simple answer is no. Throw the used potato away.
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Apparently potatoes are not natural batteries, the conversion of zinc to zinc oxide produces energy.
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They dig zinc oxide out of the ground The add coal and heat it to get zinc 2 ZnO + C --> 2 Zn + CO2
If they just burned that coal they would get energy. This way some of that energy is "stored" by making metallic zinc.
When the zinc is oxidised that energy is released.