Projektbeschreibung
Energiespeichermaterial in Dünnschichttechnologie für IoT-Sensoren
Die Energiespeicherung gewinnt angesichts der wachsenden Zahl von IoT-Geräten zunehmend an Bedeutung. Autonome Sensoren benötigen Akkus mit hoher Energiedichte, hoher Spannung und längerer Lebensdauer. Derzeitige Akkus haben zwar eine hohe Kapazität, können sich aber nicht schnell ent- und wieder aufladen. Im Gegensatz dazu können Kondensatoren Energie schneller abgeben, haben allerdings eine geringere Energiedichte. Das EU-finanzierte Projekt CITRES versucht, das Beste aus diesen beiden Möglichkeiten herauszuholen. Dabei wird das Forschungsteam Defekte in dünne Schichten eines Materials mit der Bezeichnung Relaxor-Ferroelektrikum einbringen. Die Verarbeitung von Dünnschichten aus Relaxoren verbessert die dielektrische Durchschlagsfestigkeit. Eine hohe Energiedichte in einem solchen Material kann durch Maximierung der Polarisierung und Minimierung der Leckströme erreicht werden.
Ziel
The goal of CITRES is to provide new energy storage devices with high power and energy density by developing novel multilayer ceramic capacitors (MLCCs) based on relaxor thin films (RTF).
Energy storage units for energy autonomous sensor systems for the Internet of Things (IoT) must possess high power and energy density to allow quick charge/recharge and long-time energy supply. Current energy storage devices cannot meet those demands: Batteries have large capacity but long charging/discharging times due to slow chemical reactions and ion diffusion. Ceramic dielectric capacitors – being based on ionic and electronic polarisation mechanisms – can deliver and take up power quickly, but store much less energy due to low dielectric breakdown strength (DBS), high losses, and leakage currents.
RTF are ideal candidates: (i) Thin film processing allows obtaining low porosity and defects, thus enhancing the DBS; (ii) slim polarisation hysteresis loops, intrinsic to relaxors, allow reducing the losses. High energy density can be achieved in RTF by maximising the polarisation and minimising the leakage currents. Both aspects are controlled by the amount, type and local distribution of chemical substituents in the RTF lattice, whereas the latter depends also on the chemistry of the electrode metal.
In CITRES, we will identify the influence of substituents on electric polarisation from atomic to macroscopic scale by combining multiscale atomistic modelling with advanced structural, chemical and electrical characterizations on several length scales both in the RTF bulk and at interfaces with various electrodes. This will allow for the first time the design of energy storage properties of RTF by chemical substitution and electrode selection.
The ground-breaking nature of CITRES resides in the design and realisation of RTF-based dielectric MLCCs with better energy storage performances than supercapacitors and batteries, thus enabling energy autonomy for IoT sensor systems.
Wissenschaftliches Gebiet
- natural sciencescomputer and information sciencesinternetinternet of things
- engineering and technologymaterials engineeringcoating and films
- engineering and technologyelectrical engineering, electronic engineering, information engineeringelectronic engineeringsensors
- engineering and technologymaterials engineeringceramics
- natural scienceschemical sciences
Schlüsselbegriffe
Programm/Programme
Thema/Themen
Finanzierungsplan
ERC-COG - Consolidator GrantGastgebende Einrichtung
8010 Graz
Österreich