Batteries, Technology, and Chemistry

In this highly technological world, electronics have been woven into almost every aspect of everyday life. Batteries are integrated into the majority of any electric appliance found in the home and work place, as well as our various entertainment devises. Therefore batteries could be titled as one of the most important tools to ever be invented in modern life (Elaine, 2001). The knowledge of how batteries operate is integral to understanding the basics of most modern electrical devises.

The first evidence of batteries was dated around 250B.C. (Ament, 2007). These ancient batteries were discovered in archaelogical digs in Iraq. The batteries were used in simple operations to add a thin layer of metal to objects, much the same way we plate things with gold and silver today (Fiorino, 2001). Batteries were re-discovered in the 1800’s by a man named Alessandro Volta. The volt, which is the modern electrical unit of potential, was named after him. He developed the battery by alternating pieces of electrolyte soaked discs of sodium chloride with zinc, and copper plates. These plates and discs were stacked in order, and when a wire was placed on the two poles of the battery it would produce electricity (Ament, 2007).

Battery chemistry is complex. Looking at a simple and common battery will allow us to understand the concepts of batteries as a whole. For example, the Zinc/Carbon battery uses energy released from a chemical redox reaction to generate electric current. The current is derived from the flow of electrons conducted through the metal and the movement of ions in a solution, producing an electrical conduction. For example if a container of Sulphuric acid (H2SO4) and a zinc metal rod was placed inside of the battery, the rod would immediately start to be corroded away by the acid, gas bubbles will start forming on the Zinc, and the rod and acid will begin to heat up. This happens because the acid molecules break up into three ions, two Hydrogen ions and one Sulfate ion. The atoms on the surface of the Zinc rod lose two electrons (2e-) to become Zn+2 ions. The Zn+2 ions combine with the SO4 ion to create ZnSO4, which dissolves in the acid. The electrons from the Zinc atoms combine with the Hydrogen ions in the acid to create Hydrogen gas. If a Carbon rod is placed into the acid, nothing will happen but if a wire connects the Zinc and Carbon rod two changes will occur. The electrons will flow through the wire and combine with Hydrogen on the Carbon rod, so Hydrogen gas begins bubbling of the carbon rod, and there is less heat.