Supercapacitor
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.
Dubilier Condenser Company
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.