In March 1800 Alessandro Volta, a professor at the University of Pavia in Italy, created the first battery. He described it as a "construction of an apparatus…of unfailing charge, of perpetual power…"
Volta made an electrochemical device that consisted of pairs of coin sized discs of metal - one silver, and the other zinc – stacked in piles like poker chips. A wafer of pasteboard or leather separated each pair of discs from each other. The separating wafers were soaked in salt water or some other alkaline solution such as lye. A number of piles were placed side by side and connected with metal strips. A strip of metal was attached at each end of the battery assembly and bent down to dip in a cup of mercury, which is an excellent electrical contact. The more piles Volta assembled together, the bigger the jolt he could produce.
By 1813, Sir Humphrey Davy constructed a large battery consisting of 2,000 pairs of plates and occupying a surface area of 889 feet. He used this and other early batteries to gain a deeper understanding of the concepts of basic electricity. Davy’s experiments helped explain how elementary substances, like oxygen and hydrogen, combine through electrical attraction to form natural compounds such as water.
During the same period, Michael Faraday was using voltaic piles to discover the nature electricity and magnetism. He discovered that when an electrical current is sent through a wire, it would induce a magnetic field in a parallel wire or iron bar. He also found that moving a magnet near a wire would cause electricity to flow through that wire. The battery was essential to the discovery of how electricity works.
Scientists realized that each one of Volta’s zinc-paper-silver wafers was itself a low voltage source of electricity. This discovery led to the development of individual cells. In this process, zinc was found to be one of the best anode metals. By the 1860s, a Frenchman named George Leclanché developed the forerunner of the first widely used primary battery.
Leclanché’s original cell was a "wet cell" having a liquid electrolyte of ammonium chloride. This cell was steadily improved and in the 1880s a "dry cell" version of the Leclanché cell was developed. The anode was a zinc can, the cathode was crushed manganese dioxide whit a bit of carbon mixed in, and the electrolyte was now a paste. The carbon zinc dry cell has remains much the same to this day.
Gaston Planté invented the first lead acid rechargeable battery in 1859. The lead acid battery is the most popular battery in use today and can be found in everything from automobiles to wheelchairs.
In 1899, Waldmar Jungner invented the nickel cadmium rechargeable battery. It was expensive compared to other batteries, and its use was limited. In the 1930s new electrodes were developed, and in the 40s a sealed nickel cadmium battery that recombines internal gases produced during charge was perfected. Steady improvements have been made every decade since.
Shortly before World War II Samuel Ruben invented the mercury primary cell. At first, mercury cells were expensive, and due to their small size, there weren’t used in many applications. With the invention of the transistor in the 1950s, mercury cells found their way into hearing aids and transistor radios.
In the 1950s the alkaline manganese cell was further refined. At the same time, small cameras with built in flash units were developed that required high power in a small package. Alkaline cells worked in this and other new consumer applications so well that they gained tremendous popularity. They remain one of the largest portions of revenue for portable battery sales to this day.
Development of the nickel metal hydride rechargeable cell began in the 1970s, but it was a long time before hydride alloys performed well enough to begin production. Since the late 1980s, the performance of nickel metal hydride cells has steadily improved, and there may still be room for further performance increases.
The latest developments in batteries, both primary and rechargeable, have centered on the use of lithium. Lithium is the lightest of all metals, has the greatest electrochemical potential, and provides the most energy.
Lithium primary batteries were popularized in the 1970s and 80s. They have replaced the alkaline cell in most photo applications and are better suited to military and scientific than any other type.
Attempts to make lithium rechargeable batteries go back to the 1980s. Problems with safety prevented the commercial use of the technology at that time. Finally rechargeable cells that use lithium metal were abandoned. Research shifted to the use of lithium ions found in chemicals like lithium-cobalt dioxide. Since then lithium-ion batteries have become the most popular choice for use in high tech applications such as cellular phones and laptop computers.
What’s next? Lithium polymer batteries are already being produced in small quantities, and offer the high performance of lithium combined with unparalleled packaging flexibility. Who knows what the future will bring?