Niobium capacitor
The development of solid electrolyte tantalum capacitors began in the early 1950s as a miniaturized, more reliable low-voltage support capacitor to complement the newly invented transistor. The solution found by R. L. Taylor and H. E. Haring of the Bell Labs was based on experience with ceramics. They ground down tantalum to a powder, pressed this powder into a cylindrical form and then sintered the powder particles into a pellet (“slug”) at high temperatures, between 1500 and 2000 °C, under vacuum conditions. These first sintered tantalum capacitors used a non-solid electrolyte not consistent with the concept of solid state electronics. 1952 a targeted search in the Bell Labs for a solid electrolyte by D. A. McLean and F. S. Power led to the invention of manganese dioxide as a solid electrolyte for a sintered tantalum capacitor.
Water capacitor
Capacitors can originally be traced back to a device called a Leyden jar, created by the Dutch physicist Pieter van Musschenbroek. The Leyden jar consisted of a glass jar with tin foil layers on the inside and outside of the jar. A rod electrode was directly connected to the inlayer of foil by means of a small chain or wire. This device stored static electricity created when amber and wool where rubbed together.