That old fruit battery experiment comes around each year, as regular as Thanksgiving, Christmas, and Clockwork. We’ll include an example in this post for the sake of completeness. However, we were more interested to know why some fruit and veg conduct electricity effectively while others do not. So we were real pleased when we stumbled over Farming Portal in our search. The following information will add value to your next fruit experiment.
Some Fruit and Veg are Better Ionic Conductors
Copper and silver wires popularly conduct electricity in our homes and devices. However, organic materials including vegetables and fruit – and our own bodies too – can also power electricity via free-moving ions.
Michael Hickner is an associate professor of materials science and engineering at Penn State University. He was chatting with Live Science when he explained:
- Fruit and veg conduct electricity the same way a salt solution does
- But this is due to the ions, because neither of these conduct electrons
Ionic Conductors Have Positive and Negative Ions
Any ionic conductor contains negative and positive ions. If we dissolve salt in water, the positive ions in sodium, and negative ones in chlorine create an ionic solution. Electrolytes such as these exist in every living thing. That’s why in theory any fruit or vegetable could serve as an ionic conductor, although some are better than others.
Here’s Why Some Fruit and Veg Conduct Electricity Well
Use the following information to help you choose the right fruit and veg for your experiment.
- The best fruit and vegetable batteries have high levels of superconductive ions
- Potassium and sodium are good examples, although the internal structure also counts.
- Potatoes have consistent structures. Pickles have high sodium and acidity levels.
- We could even ‘supercharge’ a potato by soaking it in salt water before the experiment.
- By contrast, tomatoes are messy inside, and oranges have internal compartments
However, We Still Need Electrodes to Make the Battery Work
All the while we have been speaking about the electrolyte in vegetable and fruit batteries. But you will also need electrodes to drive the electrons through the external circuit beyond. Because only then can the electrolyte respond by triggering a corresponding flow of ions. Happy hunting for the best combination.
More Information
The Chemistry of an Electric Battery
Planté’s Choice of Lead & Why He Made It
Preview Image: Fruit and Vegetable Baskets
