Composite multilayers capacitors with colossal permittivity for electronics and energy storage applications

Abstract

Brief Description of Technology in layman’s terms: With global demand for energy storage growing rapidly over the past decade, surging research efforts worldwide have been put in developing novel capacitors, which can achieve fast charging, high power density and long cycling lifetime than conventional batteries. This innovation of PolyU is the first report on simultaneously achieving large dielectric constant (i.e. a lot of energy can be stored); negligible dielectric loss (i.e. energy not leaking out and being wasted easily) and high energy density in flexible composite capacitors based on metal‐ion codoped colossal permittivity materials. The host titanium dioxide used in this colossal permittivity system is environment‐friendly, non‐toxic and abundant. The process developed (solution casting and hot‐pressing technique) is relatively simple and low cost for mass production of the composite films, as the ceramic powder fillers are fabricated by conventional solid‐state sintering method. The dielectric capacitors we developed based on composite multi‐layers present a relatively high dielectric constant with exceptional low loss. The maximum energy density achieved simultaneously is remarkable compared to nano‐composites with other ceramic particle fillers. Such novel composite multi‐layers capacitors are expected to be greatly superior to the conventional one‐dielectric currently used in such systems. Moreover, power electronic applications are currently limited by the capacitor size and performance. Multi‐layered capacitors can be easily patterned, with fully solid‐state construction, thus being superior to conventional electrochemical construction in many aspects including improved safety.