Descrizione del progetto
Un materiale a pellicola sottile per lo stoccaggio dell’energia per i sensori IoT
Con la crescita continua del numero dei dispositivi di Internet delle cose (IoT, Internet of Things), lo stoccaggio dell’energia sta assumendo un ruolo sempre più importante. I sensori autonomi richiedono batterie ad alta densità energetica e alta tensione, nonché dalla vita utile prolungata. Sebbene le batterie attuali abbiano una capacità elevata, non sono in grado di scaricarsi e ricaricarsi rapidamente. Per contro, i condensatori possono rilasciare energia più rapidamente, ma hanno una densità energetica minore. Il progetto CITRES, finanziato dall’UE, proverà a utilizzare i pregi di entrambi i mondi. I ricercatori introdurranno difetti in pellicole sottili di un materiale chiamato ferroelettrico relaxor. La trasformazione dei relaxor in pellicola sottile migliora la forza distruttiva. La densità ad alta energia di tale materiale può essere ottenuta massimizzando la polarizzazione e riducendo al minimo le correnti di fuga.
Obiettivo
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.
Campo scientifico
- 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
Parole chiave
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-COG - Consolidator GrantIstituzione ospitante
8010 Graz
Austria