NaBr-Assisted Sintering of Na3Zr2Si2PO12 Ceramic Electrolyte Stabilizes a Rechargeable Solid-state Sodium Metal Battery

Yang Li; Zheng Sun; Xuanyi Yuan; Haibo Jin; Yongjie Zhao

doi:10.1021/acsami.3c13483

NaBr-Assisted Sintering of Na₃Zr₂Si₂PO₁₂ Ceramic Electrolyte Stabilizes a Rechargeable Solid-state Sodium Metal Battery

ACS Appl Mater Interfaces. 2023 Oct 25;15(42):49321-49328. doi: 10.1021/acsami.3c13483. Epub 2023 Oct 17.

Authors

Yang Li^{1

2}, Zheng Sun¹, Xuanyi Yuan³, Haibo Jin¹, Yongjie Zhao^{1

2}

Affiliations

¹ Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, PR China.
² Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314000, PR China.
³ Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing 100872, PR China.

PMID: 37847183
DOI: 10.1021/acsami.3c13483

Abstract

Solid-state metal batteries with nonflammable solid-state electrolytes are regarded as the next generation of energy storage technology on account of their high safety and energy density. However, as for most solid electrolytes, low room temperature ionic conductivity and interfacial issues hinder their practical application. In this work, Na super ionic conductor (NASICON)-type Na₃Zr₂Si₂PO₁₂ (NZSP) electrolytes with improved ionic conductivity are synthesized by the NaBr-assisted sintering method. The effects of the NaBr sintering aid on the crystalline phase, microstructure, densification degree, and electrical performance as well as the electrochemical performances of the NZSP ceramic electrolyte are investigated in detail. Specifically, the NZSP-7%NaBr-1150 ceramic electrolyte has an ionic conductivity of 1.2 × 10^-3 S cm^-1 (at 25 °C) together with an activation energy of 0.28 eV. A low interfacial resistance of 35 Ω cm² is achieved with the Na/NZSP-7%NaBr-1150 interface. Furthermore, the Na/NZSP-7%NaBr-1150/Na₃V₂(PO₄)₃ battery manifests excellent cycling stability with a capacity retention of 98% after 400 cycles at 1 C and 25 °C.

Keywords: NASICON; NaBr; ionic conductivity; microstructure; solid-state sodium metal battery.