Voltaic cell

A voltaic cell is a device that changes chemical energy into electrical energy using two different metals and an electrolyte.

• The two metals react differently with the electrolyte. One metal tends to lose electrons more easily, while the other receives electrons.
• The metal that loses electrons becomes the negative terminal. These electrons travel through the connecting wire, producing an electric current that can power a small device.
• Inside the cell, the electrolyte allows charged particles to move, completing the path for the chemical reaction. Without this liquid or paste, the cell cannot keep supplying electricity.
• Think of it like a tiny chemical “push”: the different metals create a difference in electron energy, rather like water flowing from a higher level to a lower level.
• A lemon cell is a simple example. The lemon juice does not create electricity by itself; it helps the two different metals react so that electrons can move through the wire.
• As the reacting materials are gradually used up, the chemical push becomes weaker. This is why a cell eventually stops working and is called dead.