Status quo and future prospects for metallized polypropylene energy storage capacitors

Summary form only given, as follows. The most important polymer film used in commercial capacitors is the biaxially-oriented polypropylene. Other materials, such as polyesters or paper, are also used for metallized capacitors, depending on application. Polypropylene has the big advantage to be economically less expensive than the other listed materials and to have a very low equivalent series resistance (ESR) because of the propylene repeating group, which result in a regular polymer chain. Electrical breakdown behaviour will be analysed in order to improve the dielectric strength and current performance. Performance versus energy density will be investigated too. It will be given an outlook to the new proposals in the field of films, considering their supposed better dielectric and mechanical performance.