Inorganic sodium solid-state electrolytes: progress, existing issues, and solutions towards high-performance all solid-state batteries
File(s)
Published version
Author(s)
Huang, Lingjun
Huang, Chun
Type
Journal Article
Abstract
Na-ion batteries (NIBs) have gained attention as a cost-effective option for large-scale energy storage, offering electrochemical properties similar to lithium-ion batteries (LIBs). To improve safety and energy density, solid-state electrolytes (SSEs) are being incorporated into NIBs, paving the way for high-performance all-solid-state sodium-ion batteries (ASSNIBs). This review summarises recent progress in Na-based SSEs, categorised into oxides, sulfides, and halides, with particular emphasis on their crystal structures, ion conduction mechanisms, and electrochemical performance. We then critically examine the key challenges facing ASSNIBs, including low ionic conductivity, unstable electrode/electrolyte interfaces, and the reliance on rare or costly materials. To gain deeper insights into these issues, we highlight advanced characterisation and modelling techniques, including cryogenic electron microscopy, in-situ/operando characterisation, and machine learning approaches—all of which contribute to understanding Na-ion transport mechanisms and interfacial dynamics more comprehensively, and comparing with conventional electrochemical tests, structural characterisation and modelling methods. Building on these insights, we explore promising strategies such as microstructural design, mixed-ion approaches, and interface engineering to overcome the current limitations in Na SSEs. Finally, we offer perspectives on future research directions to support the rational design and optimisation of Na SSEs, ultimately advancing the development of next-generation ASSNIBs. The advanced characterisation and machine learning methodologies emphasised herein will also prove valuable for broader applications in electrochemical energy storage systems.
Date Issued
2026-02-17
Date Acceptance
2026-01-09
Citation
Electrochemical Energy Reviews, 2026, 9 (1)
ISSN
2520-8489
Publisher
Springer Science and Business Media LLC
Journal / Book Title
Electrochemical Energy Reviews
Volume
9
Issue
1
Copyright Statement
© The Author(s) Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creat ivecommons.org/licenses/by/4.0/.
License URL
Identifier
10.1007/s41918-026-00279-y
Subjects
In-situ/operando techniques
Machine learning
Na solid-state electrolytes
All solid-state batteries
Ionic conductivity
Na dendrite
Mixed-ion strategy
Interface engineering
Publication Status
Published
Article Number
6
Date Publish Online
2026-02-17