Some people have powered an electric clock with a lemon, or potato. Some have used electrolytes like lemon juice, vinegar, or even salt water. But the secret is in the cathode and anode materials. Usually use a glass or plastic jar to hold the electrolyte.
Here is a selection of DIY batteries you can make from household items. Reduce, reuse, recycle.
- Battery from carbon rod and zinc strip.
- Copper and aluminum in coke. This has a better description of using different materials and electrolytes, and the voltage output from each trial.
- Try magnesium strips (from Ebay) with one other metal, in salt water. Which metal gives the most volts?
- Stacked cell battery made from copper pennies, silver strips, and paper or cardboard soaked in salt water. This will work well until the paper/cardboard dries out. This says to use nickels, but only US nickels before 1964 contain silver. A medicine bottle might make a good container for these.
- Ye olde lemon battery.
- Grant Thompson builds a penny battery to power an LED for 2+ weeks.
- Aluminum: soda cans, aluminum foil, some old house wiring is aluminum.
- Carbon: pencil leads are carbon. Carbon rods are also found in old batteries.
- Copper: use old copper pipes. Sand off any oxidation with fine sandpaper. Use old copper wire. Older US pennies are mostly copper, but newer ones only have a thin coating of copper.
- Zinc: galvanized nails are coated in zinc. Zinc strips can be found online. The newer US pennies have a zinc core; sand off the thin copper coating.