Learn how to make battery from lemon
Successfully creating battery from a lemons is not easy.
Batteries consist of two different metals suspended in an acidic solution. Copper and Zinc work well as the metals and the citric acid content of a lemon will provide the acidic solution.
Lemon batteris will not be able torun a motor or something liek that, but it would be able to produce a dom glow from an LED.
What you need? Lemon (fresh, juicy works best), nail (I used a 2″ galvanized common nail) and the penny.