Due to its universal applicability, electrical power plays a central role in the technology which surrounds us. The "disadvantage": Electricity must be consumed by the way. It cannot be stored or created by simple devices; it must be obtained directly from a power station. The quantities of electrical energy which can be stored directly, e.g. in capacitors, are so small that they can only be used in units with very low power requirement to bridge interruptions in supply. Therefore electrical energy must be converted into other forms of energy if it is to be stored.

Batteries, also known as "accumulators", formerly "piles" are electrochemical energy stores which use the energy of chemical bonding for storage. In an overview we tell the history of these storage systems. We start with the history of electrochemical energy stores and present the early days of the lead-acid battery.

The early scientific investigations of electricity are at the same time the start of early development of electrochemical energy storage systems. Names such as Luigi Galvani (1737 to 1798) and Alessandra Cont di Volta (1745 to 1827) are associated with this work, and live on today in terms such as "galvanic cell" and "volt".

In experiments Galvani noticed that the leg of a dead frog began to twitch when it came into contact with two different metals. From this he concluded that there is a connection between electricity and muscle activity. Volta investigated the effects which are produced when different metals are wetted with salt solutions. He stacked copper and zinc plates alternately and placed a piece of card soaked in salt solution between each plate. This "voltaic pile", or the "artificial electrical organ" as Volta named it, provided electricity when the plates were connected with a wire. In further research the connection between chemical reactions and electrical energy was quickly recognized.

Within the scope of these investigations the lead/sulfuric acid/lead dioxide system was discovered: the lead-acid battery. This system was used for storing electricity for telegraphy, e.g. by Gaston Planté (1834 to 1889) in 1859. He used lead plates as electrodes. They obtained a certain capacity through repeated charging and discharging. These batteries were not yet suitable for industrial production.

At the end of the 19th century the development of electrochemical stores proceeded quickly. The dynamo and the light bulb were invented and, due to industrial developments, there was a great need for storage of electrical energy. The industrial production of lead-acid batteries began around 1880, when Emile Alphonse Faure applied for a patent for manufacture of pasted plates for lead-acid batteries.

Around 1880 Emile Alphonse Faure developed a process for covering both sides of a lead plate with a paste of lead powder and sulfuric acid. This meant that the plates could achieve a particularly high capacity with the first charge, the so-called "formation". This was a significant breakthrough which led directly to the industrial manufacture of lead-acid batteries. A number of specialized companies arose, including S. A. La Force et la Lumière in which William Thomson, later Lord Kelvin of Largs, worked as an engineering associate. The scale of absolute temperature was named after him.

At the beginning plans were made for large electricity stores in the electric power supply. For instance, W. Thompson drew up a plan to supply the city of Buffalo with electricity from the Niagara Falls. It was to be generated at 80,000 volts and supplied to Buffalo via a battery with 40,000 cells. Tapping of groups of 50 cells was to provide households with 100 volt power supply.

However, the Faure cells, in which positive and negative electrodes were wound spirally, proved not to be very durable and failed after only a few charge/discharge cycles. This was the reason for the failure of the first attempts at industrial manufacture.

In 1881 Sellon applied for a patent for a procedure in which the paste was applied to a perforated plate rather than a smooth plate. He thus achieved significantly better bonding than Faure. Sellon used antimonides as the material. At the same time Volkmar developed a similar procedure in which he used a lead grid. Thus the grid plate was invented, which was soon to be tested and applied in a range of variants. Also in 1881 C. Brush applied for a patent for a large-surface lead electrode with a ribbed surface. This was the forerunner of the large surface plates still common today.

Another type of plate which still plays an important role today was thus also available: the tubular plate or ironclad plate. In this plate design there is a lead rod, which serves as current diverter, in the center of a tube of (normally) 8 mm diameter. Mechanical support of the active material is achieved by using an outer covering. Thus different components are used for current diversion and mechanical stabilization. The result of this design: many charge/discharge cycles and a higher degree of utilization of the active material. At first the tube was made of slotted hard rubber. After the Second World War, braided glass fibers, woven material of glass and man-made fibers and purely man-made fabric or non-woven material (polyester) were introduced as tube materials.

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