Fundamental Investigations on the Sodium-Ion Transport Properties of Mixed Polyanion Solid-State Battery Electrolytes.

Olivier Guillon (1) , Jean-Noël Chotard (2, 3) , Vincent Seznec (2) , Anthony K. Cheetham (4) , Christian Masquelier (2, 3) , Gopalakrishnan Sai Gautam , Pieremanuele Canepa , Zeyu Deng , Tara P. Mishra , Eunike Mahayoni , Qianli Ma (5) , Aaron Jue Kang Tieu

1 FZJ - Forschungszentrum Jülich GmbH | Centre de recherche de Jülich | Jülich Research Centre
2 LRCS - Laboratoire réactivité et chimie des solides - UMR CNRS 7314
3 RS2E - Réseau sur le stockage électrochimique de l'énergie
4 DMSM - Department of Materials Science and Metallurgy [Cambridge University]
5 Max Planck Institute for Intelligent Systems [Tübingen]

Lithium and sodium (Na) mixed polyanion solid electrolytes for all-solid-state batteries display some of the highest ionic conductivities reported to date. However, the effect of polyanion mixing on the ion-transport properties is still not fully understood. Here, we focus on Na(1+x)Zr(2)Si(x)P(3-x)O(12) (0\,≤q\,x\,≤q\,3) NASICON electrolyte to elucidate the role of polyanion mixing on the Na-ion transport properties. Although NASICON is a widely investigated system, transport properties derived from experiments or theory vary by orders of magnitude. We use more than 2000 distinct ab initio-based kinetic Monte Carlo simulations to map the compositional space of NASICON over various time ranges, spatial resolutions and temperatures. Via electrochemical impedance spectroscopy measurements on samples with different sodium content, we find that the highest ionic conductivity (i.e., about 0.165\,S\,cm(-1) at 473\,K) is experimentally achieved in Na(3.4)Zr(2)Si(2.4)P(0.6)O(12), in line with simulations (i.e., about 0.170\,S\,cm(-1) at 473\,K). The theoretical studies indicate that doped NASICON compounds (especially those with a silicon content x\,≥q\,2.4) can improve the Na-ion mobility compared to undoped NASICON compositions.

Domaines: Matériaux

Olivier Guillon, Jean-Noël Chotard, Vincent Seznec, Anthony K. Cheetham, Christian Masquelier, et al.. Fundamental Investigations on the Sodium-Ion Transport Properties of Mixed Polyanion Solid-State Battery Electrolytes.. Nature Communications, 2022, 13 (1), pp.4470. ⟨10.1038/s41467-022-32190-7⟩. ⟨hal-03746084⟩