Stable Interfaces in a Sodium Metal-Free, Solid-State Sodium-Ion Battery with Gradient Composite Electrolyte

Lingbing Ran; Shiwei Tao; Ian Gentle; Bin Luo; Ming Li; MdMasud Rana; Lianzhou Wang; Ruth Knibbe

doi:10.1021/acsami.1c09792

Stable Interfaces in a Sodium Metal-Free, Solid-State Sodium-Ion Battery with Gradient Composite Electrolyte

ACS Appl Mater Interfaces. 2021 Aug 25;13(33):39355-39362. doi: 10.1021/acsami.1c09792. Epub 2021 Aug 11.

Authors

Lingbing Ran¹, Shiwei Tao¹, Ian Gentle², Bin Luo³, Ming Li¹, MdMasud Rana¹, Lianzhou Wang³, Ruth Knibbe¹

Affiliations

¹ School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072, Australia.
² School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia.
³ Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, QLD 4072, Australia.

PMID: 34378913
DOI: 10.1021/acsami.1c09792

Abstract

Composite electrolytes (CE) combining a ceramic filler and a polymer matrix is an effective way to enhance battery safety. But the increased ceramic filler mass fraction decreases the flexibility, which increases the interfacial resistance. To alleviate interfacial resistance further, a gradient composite electrolyte (GCE) using a Sc, Ge-doped Na₃Zr₂Si₂PO₁₂ (NZSP) as the ceramic filler and poly(ethylene oxide) (PEO) as the polymer matrix is proposed. The outer layer contains a low concentration of ceramic filler to improve interfacial contact, and the central layer contains a high concentration of ceramic filler to inhibit dendrite penetration. This GCE possesses an enhanced conductivity (4.0 × 10^-5 S cm^-1 at 30 °C) and a reduced interfacial resistance. Furthermore, the safety was boosted using Sn₄P₃@CNT/C as the high-capacity anode active material and Na₃V₂(PO₄)₃ (NVP) as the cathode active material. This ultrasafe sodium metal-free, solid-state sodium-ion battery (SSSIB) displays an impressive cycling performance.

Keywords: NASICON; composite electrolyte; polymer; sodium metal-free anode; solid-state battery.