5F40.10 Simple Battery

PIRA 5F40.10 Simple Battery

Click your browser's back button to return to the demo master list.

Photo of the Demonstration at the University of Texas at Austin.

top left image: no heat, top right image: with heat, bottom left image: with heat pressed down, bottom right image: potato battery setup.

Faculty Instructions:

Setup 1
Set the hot plate to a desired but safe temperature. Be cautious when using hot plate, it conducts quickly!
Lay the thermoelectric generator on the edge of the hot plate. Ensure no wires touch the hot plate
Allow the thermoelectric generator to heat up and the increased voltage will display on the multimeter
To produce a greater voltage, you may press the thermoelectric generator against the hot plate.

Setup 2.
Pushing a nail and copper wire into opposite ends of a potato (bring your own!), it acts as a battery where voltage can also be measured.

Setup 3.
If faculty desire, with a couple more potatoes from home (bring your own!) they can be set up in parallel with light bulbs attached to show the current through the circuit.

Concept Conveyed:

The thermoelectric generator converts temperature differences into electrical energy (Seebeck thermoelectric effect).
The potato battery setup acts as a salt-bridge between the nail and wire.
The voltage produced should start off relatively small >.02V and gradually increases as it sits on the hot plate (top right image) or rapidly increases if pressed against the hot plate (bottom left image).

Demo Staff Notes:

Ensure alligator clips are plugged into multimeter and are attached to the respective ends of the thermoelectric generator.
Provide faculty with hot plate and heat resistant gloves.