How To Make A Potato Battery

This experiment shows you how to make a potato battery and measure the voltage it produces. The current and the voltage produced will be small but it demonstrates how batteries work.

Materials needed: 1. One large potato 2. A voltmeter to measure voltage 3. A galvanized nail. A four penny or larger size will work 4. Two inch long piece of single strand copper wire. Either 12 or 14 gauge 4. Piece of sandpaper or steel wool Procedure: a. Scuff the nail and copper wire with the sandpaper or steel wool until its shiny b. Push the nail and piece of wire into the flat side of the potato about and inch keeping them an inch or more apart. Make sure they don't touch. c. Set the voltmeter on its lowest whole number DC voltage. Its 2 on my meter. d. Plug the red lead of the voltmeter into the +voltage slot. Plug the black lead into the -negative slot(also called common) e. The nail will be the negative or cathode of the potato battery and the copper wire will be the plus or anode of the battery f. Turn on the voltmeter and touch the red positive lead to the copper wire and the black negative lead to the nail My potato battery produced 0.88 volts. The current from this battery will be too small to light a bulb or power an appliance.

Tips For A Potato Battery Science Fair Project

2. Will larger electrodes increase the amount of current the potato can produce?

3. Will connecting more than one battery in series produce more voltage? What about more current?

4. What type material will work best for electrodes?

5. Do the electrodes have to be different types of metals in each battery?

6. Will the same metal such as copper work for all the electrodes?