The aim of this is to show how a battery works. You can link a few of these lemon in series to run a small LED light, calculator or clock. The lemon battery works because of the process of oxidation and reduction on metals. The zinc acts as the anode and is oxidized while the copper acts as a cathode where hydrogen is reduced. When the zinc hits the lemon juice, electrons jump off and try to make their way to the copper side through the electrolytic juice. We have the makings of a battery albeit not a very powerful one. But we can build on this.

If we attach a wire between the two metals then we create a path of lesser resistance which for the electrons is a rather attractive option. This creates power running through the wire which can be measured and used. Eventually the battery will reach equilibrium (stability) by corroding the surface of the copper and forming a barrier so no copper is touching the lemon juice. Since this was discovered scientists have experimented with different metals and electrolytes to create more power with less corrosion and carbon and zinc perform more efficiently than the battery shown here. Today we buy lithium batteries which use lithium salts and manganese dioxide as the anode and cathode. They use a salt of lithium dissolved in an organic solvent as the electrolytic solution and a porous carbon material as a current collector.

You can link a few of these in series and generate enough power to run a small LED light, calculator or clock. You can even recharge your iPod using a lemon! So next time you go camping remember to take a few lemons with you.