Mechanics of Multi-responsive Ceramics for Electrical Capacitors with High power/Energy density

Iowa State University, Ames IA

Investigators

Abstract

This project is focused on the critical mechanics issues in antiferroelectric ceramics subjected to electrical and/or mechanical loads. Compared to most dielectric materials used in capacitors for electrical energy storage, special (e.g. PbZrO3-based) antiferroelectric ceramics display a much higher energy density due to the reversible antiferroelectric\ferroelectric phase transition, which is manifested by an abrupt development of large amounts of electrical charge and volume strain. As such, the phase transition makes these ceramics responsive to both electric fields and mechanical stresses and forms the fundamental basis for energy-storage applications. The associated volume change induces complicated internal stress states in the ceramic and thus influences the reliability of capacitors. Through an integrated experimental and theoretical approach, this project aims to rigorously establish the novel phase-transition-toughening mechanism in antiferroelectric ceramics, which will lead to highly efficient and highly reliable energy-storage devices. The success of this project will pave the way to the large-scale usage of antiferroelectric capacitors with high power/energy density. Such capacitors are urgently needed for renewable energy sources, such as wind and solar. Their intermittent nature requires efficient energy-storage technologies to ensure around-the-clock delivery. Furthermore, this project is designed to have a broad impact on both graduate and undergraduate education. Undergraduate students, especially those from underrepresented groups, will be exposed to this research through various existing educational programs at Iowa State University. In addition, participating graduate students will spend some summer months in Germany for part of the experimental work, thus acquiring international experiences.