Alessandro Volta: From Frog Leg Experiment to Battery Invention

A battery is a device consisting of one or more electrochemical cells that have external connections to provide electrical power. Batteries can be used to power remotes, wall clocks, mice, cell phones, electric cars, and much more. However, the battery doesn't just appear out of thin air. There is a long history behind the invention of batteries. The term battery was first used by Benjamin Franklin, an American scientist and politician, in 1749. He used the term battery to describe a series of capacitors that he connected together for his electrical research. Capacitors are devices that can store static electrical charges. Then, the term battery is also used for electrochemical cells that are connected together to provide electrical power. An electrochemical cell is a device that can convert chemical energy into electrical energy using redox reactions. Redox reactions are reactions that involve the transfer of electrons between the substances involved. In an electrochemical cell, there are two electrodes made of different metals and immersed in an electrolyte solution. Electrolytes are substances that can conduct electric current. The electrode that has a positive sign is called the cathode, while the one that has a negative sign is called the anode. Electrons will flow from the anode to the cathode through an external electrical circuit and produce an electric current. The inventor of the battery for the first time was Alessandro Volta, an Italian physicist and chemist. In 1800, he created a battery with a simple method called the Volta stack. The Volta stack is an alternating arrangement of metal disks, such as copper and zinc, separated by paper or cloth moistened with an acid or salt solution. The ends of the Volta stack were connected by wires to form an electric circuit. The Volta stack could produce a high enough electric voltage by increasing the number of metal disks. Electric voltage is the potential difference between two points in an electric circuit. The unit of electric voltage is named volt to honor Volta's service. Volta was inspired to make a battery after learning about Luigi Galvani's research, an Italian doctor and biologist in 1780. Galvani discovered that a cut frog leg could twitch when touched by a scalpel made of different metals. Galvani hypothesized that there was animal electricity flowing from the nerves to the muscles. However, Volta refuted Galvani's hypothesis and proved that the movement of the frog leg was caused by the electric current generated by the contact between two different metals. Volta replaced the frog leg with paper moistened with an acid or salt solution and detected the electric current by another way. The invention of the battery by Volta was a great breakthrough in the field of science and technology. The Volta battery enabled scientists to conduct experiments with stable and measurable electric current. The Volta battery also became the basis for the development of subsequent batteries such as the Danielle battery, the Leclanche battery, and the dry battery. These batteries have differences in the type of metal, electrolyte, and shape.