Who Invented the Battery?
A battery, which is actually an electric cell, is a device that produces electricity from a chemical reaction. Strictly speaking, a battery consists of two or more cells connected in series or parallel, but the term is generally used for a single cell.
A cell consists of a negative electrode; an electrolyte, which conducts ions; a separator, also an ion conductor; and a positive electrode. In 1748, Benjamin Franklin first coined the term ‘battery’ to describe an array of charged glass plates.
From 1780 to 1786 Luigi Galvani demonstrated what we now understand to be the electrical basis of nerve impulses, and provided the cornerstone of research for later inventors like Alessandro Volta.
Volta invented the voltaic pile and discovered the first practical method of generating electricity in 1800. Constructed of alternating discs of zinc and copper with pieces of cardboard soaked in brine between the metals, the voltaic pile produced electrical current.
Volta’s original pile models had some technical flaws, one of them involving the electrolyte leaking and causing short-circuits due to the weight of the discs compressing the brine-soaked cloth. A Scotsman named William Cruickshank solved this problem by laying the elements in a box instead of piling them in a stack. This was known as the trough battery.
Volta himself invented a variant that consisted of a chain of cups filled with a salt solution, linked together by metallic arcs dipped into the liquid. This was known as the Crown of Cups.
These arcs were made of two different metals (e.g., zinc and copper) soldered together. This model also proved to be more efficient than his original piles, though it did not prove as popular.
Another problem with Volta’s batteries was short battery life (an hour’s worth at best), which was caused by two phenomena. The first was that the current produced electrolysed the electrolyte solution, resulting in a film of hydrogen bubbles forming on the copper, which steadily increased the internal resistance of the battery (this effect, called polarization, is counteracted in modern cells by additional measures).
The other was a phenomenon called local action, wherein minute short-circuits would form around impurities in the zinc, causing the zinc to degrade. The latter problem was solved in 1835 by William Sturgeon, who found that amalgamated zinc, whose surface had been treated with some mercury, didn’t suffer from local action.
Despite its flaws, Volta’s batteries provided a steadier current than Leyden jars, and made possible many new experiments and discoveries, such as the first electrolysis of water by Anthony Carlisle and William Nicholson.
In 1836, an Englishman, John F. Daniel invented the Daniel cell that used two electrolytes: copper sulfate and zinc sulfate. The Daniel cell was somewhat safer and less corrosive than the Volta cell. In 1859, a French inventor, Gaston Plante developed the first practical storage lead-acid battery that could be recharged.
This type of battery is primarily used in automobiles today. Lewis Urry developed the small alkaline battery in 1949. Alkaline batteries last five to eight times as long as zinc-carbon cells, their predecessors. This was not a patentable invention, since Volta and others long ago created the principles of batteries.