Lemon Battery

A lemon battery is a kind of battery usually made for educational purpose. Most commonly, a piece of zinc metal (such as a galvanized nail) is needed along with a piece of copper (such as a penny). They both are inserted into a lemon and connected by wires. Power is generated because of the reaction of the metals and it helps to power a small device such as a light-emitting diode (LED).

What is a Lemon Battery?

A lemon battery is a very basic kind of battery made using zinc metal like a galvanized nail and a copper piece for educational purposes. The lemon battery gives us an idea about the type of chemical reaction (oxidation-reduction) that happens in batteries.

The chemistry Behind the Lemon Battery

With the help of an external circuit when the cell is providing an electric current, the zinc present at the surface of the zinc electrode dissolves into the solution. Zinc atoms dissolve into the liquid electrolyte as electrically charged ions \(\left ( Zn^{2+} \right\), thus leaving 2 negatively charged electrons \(\left ( e^{-} \right\) behind in the metal:

\(Zn \rightarrow Zn^{2+} + 2e^{-}\) .

This is an oxidation reaction. As zinc enters the electrolyte, two positively charged hydrogen ions \(\left ( H^{+} \right\) from the electrolyte combines with two electrons at the copper electrode’s surface to form an hydrogen molecule \(\left ( H_{2} \right\):

\(2H^{+} + 2e^{-} \rightarrow  H_{2}\)

This is reduction reaction.

How to Make a Lemon Battery

Supplies Required

• 4 pieces of lemon
• 4 pieces of copper metal
• 5 alligator clip wires
• 4 pieces of galvanized nails
• A LED light to power up.

Procedure

1- We need to squeeze the lemons to release the juice and pulp inside.

2 – We need to Insert one galvanized nail and one piece of copper into each lemon.

3 – Now we have to connect the ends of one wire to a galvanized nail in one lemon and the other wire to the piece of copper in another lemon. One has to do this with each of the four lemons until all are connected. When you finish, you should have one nail and one piece of copper unattached.

4 – Now the most important part is to connect the unattached piece of copper (positive) and the unattached nail (negative) to the positive and negative connections of your light. As soon as the connection is complete, the lemon will act as the battery.

5 – Turn on your light and change the voltage using lemon power.

Learning Outcomes

For pupils, in the range of 5–9 years of age, the educational goal is utilitarian. They get to learn that batteries are devices that can power other devices, as long as they are connected by a conductive material.

For children ranging between the age of 10−13, they learn that how batteries are in use to illustrate the connection between chemistry and electricity as well as to deepen the circuit concept for electricity.

Older students and college students learn that batteries serve to illustrate the principles of oxidation-reduction reactions.

FAQs on Lemon Battery

Q.1. How much power can a lemon battery produce?

Answer – A single lemon produces about 7/10 of a volt of electricity. If you connect two such lemons together then you can power an inexpensive digital watch that uses about 1.5 volts.