Make a Lemon Battery
Use two different metals pushed into a lemon to make a tiny battery that lights an LED.
Materials
- Fresh lemon
- Copper coin/strip
- Galvanized nail (zinc)
- LED or buzzer
- Jumper wires
Steps
- Roll the lemon to loosen juice, then insert copper and zinc far apart.
- Connect wires: copper to LED +, zinc to LED −.
- If dim, add a second lemon in series (zinc of lemon #1 to copper of #2).
- Measure voltage with a multimeter and record results.
What’s happening (the science)
- The lemon’s juice acts as an electrolyte. Zinc atoms give up electrons (oxidation) and copper accepts them (reduction).
- Series connections add voltage; parallel adds current capability.
Safety & cleanup
- Wash hands after handling zinc‑coated nails.
- Don’t ingest metals or lemon after experiment.
- Dispose of parts responsibly.
Tip: Extend this activity by asking students to measure, graph, or compare versions (e.g., different designs or variables).