High-Entropy Solid-State Na-Ion Conductor for Stable Sodium-Metal Batteries

Ge Sun; Hezhe Lin; Shiyu Yao; Zhixuan Wei; Nan Chen; Gang Chen; Huichao Zhao; Fei Du

doi:10.1002/chem.202300413

High-Entropy Solid-State Na-Ion Conductor for Stable Sodium-Metal Batteries

Chemistry. 2023 May 16;29(28):e202300413. doi: 10.1002/chem.202300413. Epub 2023 Apr 4.

Authors

Ge Sun¹, Hezhe Lin¹, Shiyu Yao¹, Zhixuan Wei¹, Nan Chen¹, Gang Chen¹, Huichao Zhao², Fei Du¹

Affiliations

¹ Key Laboratory of Physics and Technology for, Advanced Batteries (Ministry of Education), State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China.
² China FAW Group Co. Ltd., No.1, Xinhongqi Street, Changchun, 130012, China.

PMID: 36864366
DOI: 10.1002/chem.202300413

Abstract

Solid-state sodium-metal batteries (SSBs) hold great promise for their merits in low-cost, high energy density, and safety. However, developing solid electrolyte (SE) materials for SSBs with high performance is still a great challenge. In this study, high-entropy Na_4.9 Sm_0.3 Y_0.2 Gd_0.2 La_0.1 Al_0.1 Zr_0.1 Si₄ O₁₂ was synthesized at comparatively low sintering temperature of 950 °C with high room-temperature ionic conductivity of 6.7×10^-4 S cm^-1 and a low activation energy of 0.22 eV. More importantly, the Na symmetric cells using high-entropy SE show a high critical current density of 0.6 mA cm^-2 , outstanding rate performance with fairly flat potential profiles at 0.5 mA cm^-2 and steady cycling over 700 h under 0.1 mA cm^-2 . Solid-state Na₃ V₂ (PO₄ )₃ ||high-entropy SE||Na batteries are further assembled manifesting a desirable cycling stability with almost no capacity decay after 600 cycles and high Columbic efficiency over 99.9 %. The findings present opportunities for the design of high-entropy Na-ion conductors toward the development of SSBs.

Keywords: Na stripping/plating; hexagonal-prismatic Na5MSi4O12; high-entropy; sodium-metal batteries; solid electrolytes.

Abstract

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