Instruct: Given a question, retrieve relevant passages that can help answer the question.
Query: Who developed the capacitor?
In October 1745, Ewald Georg von Kleist of Pomerania, Germany, found that charge could be stored by connecting a high-voltage electrostatic generator by a wire to a volume of water in a hand-held glass jar.[4] Von Kleist's hand and the water acted as conductors, and the jar as a dielectric (although details of the mechanism were incorrectly identified at the time). Von Kleist found that touching the wire resulted in a powerful spark, much more painful than that obtained from an electrostatic machine. The following year, the Dutch physicist Pieter van Musschenbroek invented a similar capacitor, which was named the Leyden jar, after the University of Leiden where he worked.[5] He also was impressed by the power of the shock he received, writing, "I would not take a second shock for the kingdom of France."[6]
With the development of plastic materials by organic chemists during the Second World War, the capacitor industry began to replace paper with thinner polymer films. One very early development in film capacitors was described in British Patent 587,953 in 1944. The introduction of plastics in plastic film capacitors was approximately in the following historic order: polystyrene (PS) in 1949, polyethylene terephthalate (PET/"polyester") and cellulose acetate (CA) in 1951, polycarbonate (PC/Lexan) in 1953, polytetrafluoroethylene (PTFE/Teflon) in 1954, polyparylene in 1954, polypropylene (PP) in 1954, polyethylene (PE) in 1958, and polyphenylene sulphide (PPS) in 1967. By the mid-1960s there was a wide range of different plastic film capacitors offered by many, mostly European and US manufacturers. German manufacturers such as WIMA, Roederstein, Siemens and Philips were trend-setters and leaders in a world market driven by consumer electronics.
The easy-to-mold ceramic material facilitated the development of special and large styles of ceramic capacitors for high-voltage, high-frequency (RF) and power applications.
With the development of semiconductor technology in the 1950s, barrier layer capacitors, or IEC class 3/EIA class IV capacitors, were developed using doped ferroelectric ceramics. Because this doped material was not suitable to produce multilayers, they were replaced decades later by Y5V class 2 capacitors.
In the 1960s, the better availability of niobium ore compared with tantalum ore prompted research into niobium electrolytic capacitors in the former Soviet Union. Here they took the place that was filled by tantalum capacitors in the West. With the collapse of the Iron Curtain, this know-how has been publicized in the West. In the late 1990s the interest in this technology awoke in the major capacitor manufacturers. The materials and processes used to produce niobium capacitors are essentially the same as for tantalum capacitors. However, a price rise for tantalum in 2000/2001 encouraged the development of niobium electrolytic capacitors with manganese dioxide electrolyte, as well as polymer electrolyte which have been available since 2002.
Every electrolytic capacitor in principle forms a "plate capacitor" whose capacitance increases with the electrode area (A) and the permittivity (ε) and decreases with the thickness (d) of the dielectric.
Faulty capacitors have been a problem since capacitors' initial development, but the first flawed capacitors linked to Taiwanese raw material problems were reported by the specialist magazine Passive Component Industry in September 2002.[1] Shortly thereafter, two mainstream electronics journals reported the discovery of widespread prematurely failing capacitors, from Taiwanese manufacturers, in motherboards.[3][4]
The development of tantalum electrolytic capacitors in the early 1950s with manganese dioxide as solid electrolyte, which has a 10 times better conductivity than all other types of non-solid electrolytes, also influenced the development of aluminum electrolytic capacitors. In 1964 the first aluminum electrolytic capacitors with solid electrolyte (Solid aluminum capacitor (SAL)) appeared on the market, developed by Philips.
This development to low ESR capacitors with high CV-volumes in chip style for the rapid growing SMD technology in the 1990s increased the demand on tantalum chips dramatically. However, another price explosion for tantalum in 2000/2001 forced the development of niobium electrolytic capacitors with manganese dioxide electrolyte, which have been available since 2002. The materials and processes used to produce niobium-dielectric capacitors are essentially the same as for existing tantalum-dielectric capacitors. The characteristics of niobium electrolytic capacitors and tantalum electrolytic capacitors are roughly comparable.
A stolen recipe for such a water-based electrolyte, in which important stabilizing substances were absent, led in the years 2000 to 2005 to the problem of mass-bursting capacitors in computers and power supplies, which became known under the term "capacitor plague". In these e-caps the water reacts quite aggressively and even violently with aluminum, accompanied by strong heat and gas development in the capacitor, and often led to the explosion of the capacitor.
Last but not least the electric double-layer capacitor (now Supercapacitors) were invented. In 1957 H. Becker developed a "Low voltage electrolytic capacitor with porous carbon electrodes".[14][15][16] He believed that the energy was stored as a charge in the carbon pores used in his capacitor as in the pores of the etched foils of electrolytic capacitors. Because the double layer mechanism was not known by him at the time, he wrote in the patent: "It is not known exactly what is taking place in the component if it is used for energy storage, but it leads to an extremely high capacity."
With the development of plastic materials by organic chemists during the Second World War, the capacitor industry began to replace paper with thinner polymer films. One very early development in film capacitors was described in British Patent 587,953 in 1944.[14]
A stolen recipe of such a water-based electrolyte, in which important stabilizing substances were absent, led in the years 2000 to 2005 to the problem of mass-bursting capacitors in computers and power supplies, which became known under the term "Capacitor Plague". In these capacitors the water reacts quite aggressively and even violently with aluminum, accompanied by strong heat and gas development in the capacitor, and often leads to the explosion of the capacitor.
Industrial espionage was implicated in the capacitor plague, in connection with the theft of an electrolyte formula. A materials scientist working for Rubycon in Japan left the company, taking the secret water-based electrolyte formula for Rubycon's ZA and ZL series capacitors, and began working for a Chinese company. The scientist then developed a copy of this electrolyte. Then, some staff members who defected from the Chinese company copied an incomplete version of the formula and began to market it to many of the aluminium electrolytic manufacturers in Taiwan, undercutting the prices of the Japanese manufacturers.[1][42] This incomplete electrolyte lacked important proprietary ingredients which were essential to the long-term stability of the capacitors[4][23] and was unstable when packaged in a finished aluminum capacitor. This faulty electrolyte allowed the unimpeded formation of hydroxide and produced hydrogen gas.[36]
Capacitors store energy in an electrostatic field between their plates. Given a potential difference across the conductors (e.g., when a capacitor is attached across a battery), an electric field develops across the dielectric, causing positive charge (+Q) to collect on one plate and negative charge (-Q) to collect on the other plate. If a battery is attached to a capacitor for a sufficient amount of time, no current can flow through the capacitor. However, if an accelerating or alternating voltage is applied across the leads of the capacitor, a displacement current can flow. Besides capacitor plates, charge can also be stored in a dielectric layer.
Dielectric absorption occurs when a capacitor that has remained charged for a long time discharges only incompletely when briefly discharged. Although an ideal capacitor would reach zero volts after discharge, real capacitors develop a small voltage from time-delayed dipole discharging, a phenomenon that is also called dielectric relaxation, "soakage" or "battery action".
The Dubilier Condenser Company was the earliest commercial manufacturer of electronic capacitors, formerly known as condensers, which were widely used in early radio receivers (wireless sets). The company was founded in New York in 1920, by William Dubilier, who was responsible for many early developments in the field of electronics and radio, including the use of mica in capacitors. Dubilier was a name commonly found on capacitors in early wireless sets in Britain alongside TCC, Wima, and others. Dubilier Condenser was later merged into Cornell Dubilier.
Another price explosion for tantalum in 2000/2001 forced the development of niobium electrolytic capacitors with manganese dioxide electrolyte, which have been available since 2002. Niobium is a sister metal to tantalum and serves as valve metal generating an oxide layer during anodic oxidation. Niobium as raw material is much more abundant in nature than tantalum and is less expensive. It was a question of the availability of the base metal in the late 1960s which led to development and implementation of niobium electrolytic capacitors in the former Soviet Union instead of tantalum capacitors as in the West. The materials and processes used to produce niobium-dielectric capacitors are essentially the same as for existing tantalum-dielectric capacitors. The characteristics of niobium electrolytic capacitors and tantalum electrolytic capacitors are roughly comparable.
From simple beginnings film capacitors developed into a very broad and highly specialized range of different types. By the end of the 20th century mass production of most film capacitors had shifted to the Far East. A few large companies still produce highly specialized film capacitors in Europe and in the US, for power and AC applications.
Since capacitors' energy content increases with the square of the voltage, researchers were looking for a way to increase the electrolyte's breakdown voltage. In 1994 using the anode of a 200V high voltage tantalum electrolytic capacitor, David A. Evans developed an "Electrolytic-Hybrid Electrochemical Capacitor". These capacitors combine features of electrolytic and electrochemical capacitors. They combine the high dielectric strength of an anode from an electrolytic capacitor with the high capacitance of a pseudocapacitive metal oxide (ruthenium (IV) oxide) cathode from an electrochemical capacitor, yielding a hybrid electrochemical capacitor. Evans' capacitors, coined Capattery, had an energy content about a factor of 5 higher than a comparable tantalum electrolytic capacitor of the same size. Their high costs limited them to specific military applications.
Often switched-capacitor circuits are used to provide accurate voltage gain and integration by switching a sampled capacitor onto an op-amp with a capacitor formula_11 in feedback. One of the earliest of these circuits is the parasitic-sensitive integrator developed by the Czech engineer Bedrich Hosticka. Here is an analysis. Denote by formula_12 the switching period. In capacitors,
In field installations of electrical power distribution equipment, capacitor bank fault tolerance is often improved by connecting multiple capacitors in parallel, each protected with an internal or external fuse. Should an individual capacitor develop an internal short, the resulting fault current (augmented by capacitive discharge from neighboring capacitors) blows the fuse, thus isolating the failed capacitor from the remaining devices. This technique is analogous to the "T metallization" technique described above, but operating at a larger physical scale. More-complex series and parallel arrangements of capacitor banks are also used to allow continuity of service despite individual capacitor failures at this larger scale.
Lowering ESR and ESL remains a major research and development objective for all polymer capacitors. Some constructive measures can have also a major impact on the electrical parameters of capacitors. Smaller ESR values can be achieved for example by parallel connection of several conventional capacitor cells in one case. Three parallel capacitors with an ESR of 60 mΩ each have a resulting ESR of 20 mΩ. This technology is called “multi-anode” construction and will be used at polymer tantalum capacitors. In this construction up to six individual anodes in one case are connected. This design is offered as polymer tantalum chip capacitors as well as lower expensive tantalum chip capacitors with MnO electrolyte. Multi-anode polymer tantalum capacitors have ESR values on the single-digit milliohm range.
Aluminum electrolytic capacitors form the bulk of the electrolytic capacitors used in electronics because of the large diversity of sizes and the inexpensive production. Tantalum electrolytic capacitors, usually used in the SMD version, have a higher specific capacitance than the aluminum electrolytic capacitors and are used in devices with limited space or flat design such as laptops. They are also used in military technology, mostly in axial style, hermetically sealed. Niobium electrolytic chip capacitors are a new development in the market and are intended as a replacement for tantalum electrolytic chip capacitors.
Dielectric absorption is the name given to the effect by which a capacitor, which has been charged for a long time, discharges only incompletely. Although an ideal capacitor remains at zero volts after discharge, real capacitors will develop a small voltage coming from time-delayed dipole discharging, a phenomenon that is also called dielectric relaxation, "soakage" or "battery action".
The first electrolytic capacitor developed was an aluminum electrolytic capacitor with a liquid electrolyte, invented by Charles Pollak in 1896. Modern electrolytic capacitors are based on the same fundamental design. After roughly 120 years of development billions of these inexpensive and reliable capacitors are used in electronic devices.
In the late 1960s capacitors developed quickly as better materials, such as mylar, were used in their production. Capacitors became more reliable, smaller, and able to withstand higher voltages. Sprague Electric's "Orange Drop" capacitors were well received by manufacturers and designers. They set the standard for "modern" capacitors in appearance and performance. Today, some designers and restorers will use only Sprague/Vishay Orange Drops or other Sprague capacitors. After the breakup of Sprague Electric, the Orange Drop Capacitor line was continued by SBE Inc until 2012, when the Orange Drop product line was sold to Cornell Dubilier.