The principle of the fruit battery is that the metal pieces displace the hydrogen ions of the acid in the fruit, which can generate an electric charge.

The reason why fruits can generate electricity, its principle is that fruits contain a large number of fruit acids, which is a good electrolyte; secondly, inserted into the fruit of the two metal pieces usually electrochemical activity is not the same, which is more active metal piece can replace the fruit in the acidic substances of hydrogen ions, can generate a charge, resulting in a change in voltage, so the formation of a primary cell.

In the process of fruit power generation and voltaic pile of electricity experiments, the two metal pieces are the same, the fruit acid in the fruit is equivalent to dilute sulfuric acid. And there are experiments to prove that under the same conditions, different fruit battery voltage is different, one of the key factors in the formation of fruit battery also lies in the acid content of the fruit.

Method of making fruit battery

1, 3 lemons (lime, apple, pear, pineapple can also be).

2, 3 shiny copper coins. We use nickels (or copper pieces).

3, 3 galvanized screws (you can also use other more active metals, not necessarily zinc, as long as you can do the displacement) (or aluminum pieces).

4, 4 wires, preferably with clips on the wires (to hold the copper coins and screws).

5, a knife and small paper sticker labels.

6. Light-emitting diodes (LEDs) with low voltage drivers. We use RadioShack's Model 276-330.

7. A 35mm plastic film case or similar small container. It is best to use a black opaque film case. (For shading and easy viewing).

8, a nail or small awl (for drilling holes in the blackout container).