How a battery works

13th Apr 2016


  • A battery is a device that stores chemical energy and converts it to electrical energy.
  • The chemical reactions in a battery involve the flow of electrons from one material (electrode) to another, through an external circuit.
  • The flow of electrons provides an electric current that can be used to do work.
  • To balance the flow of electrons, charged ions also flow through an electrolyte solution that is in contact with both electrodes.
  • Different electrodes and electrolytes produce different chemical reactions that affect how the battery works, how much energy it can store and its voltage.

Imagine a world without batteries. All those portable devices we’re so dependent on would be so limited! We’d only be able to take our laptops and phones as far as the reach of their cables, making that new running app you just downloaded onto your phone fairly useless.

Luckily, we do have batteries. Back in 150 BC in Mesopotamia, the Parthian culture used a device known as the Baghdad battery, made of copper and iron electrodes with vinegar or citric acid. Archaeologists believe these were not actually batteries but were used primarily for religious ceremonies.

The invention of the battery as we know it is credited to the Italian scientist Alessandro Volta, who put together the first battery to prove a point to another Italian scientist, Luigi Galvani. In 1780, Galvani had shown that the legs of frogs hanging on iron or brass hooks would twitch when touched with a probe of some other type of metal. He believed that this was caused by electricity from within the frogs’ tissues, and called it ‘animal electricity’.

To read the full article, click here.

Source: NOVA