Origin of Superionic Li3Y1- xInxCl6 Halide Solid Electrolytes with High Humidity Tolerance

Xiaona Li; Jianwen Liang; Keegan R Adair; Junjie Li; Weihan Li; Feipeng Zhao; Yongfeng Hu; Tsun-Kong Sham; Li Zhang; Shangqian Zhao; Shigang Lu; Huan Huang; Ruying Li; Ning Chen; Xueliang Sun

doi:10.1021/acs.nanolett.0c01156

Origin of Superionic Li₃Y_{1- x}In_xCl₆ Halide Solid Electrolytes with High Humidity Tolerance

Nano Lett. 2020 Jun 10;20(6):4384-4392. doi: 10.1021/acs.nanolett.0c01156. Epub 2020 May 19.

Authors

Xiaona Li¹, Jianwen Liang¹, Keegan R Adair¹, Junjie Li¹, Weihan Li¹, Feipeng Zhao¹, Yongfeng Hu², Tsun-Kong Sham³, Li Zhang⁴, Shangqian Zhao⁴, Shigang Lu⁴, Huan Huang⁵, Ruying Li¹, Ning Chen², Xueliang Sun¹

Affiliations

¹ Department of Mechanical and Materials Engineering, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada.
² Canadian Light Source, 44 Innovation Boulevard, Saskatoon, Saskatchewan S7N 2V3, Canada.
³ Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada.
⁴ China Automotive Battery Research Institute Co. Ltd, Fifth Floor, No. 43, Mining Building, North Sanhuan Middle Road, Beijing 100088, China.
⁵ Glabat Solid-State Battery Inc., 700 Collip Circle, London, Ontario N6G 4X8, Canada.

PMID: 32406692
DOI: 10.1021/acs.nanolett.0c01156

Abstract

The high ionic conductivity, air/humidity tolerance, and related chemistry of Li₃MX₆ solid-state electrolytes (SSEs, M is a metal element, and X is a halogen) has recently gained significant interest. However, most of the halide SSEs suffer from irreversible chemical degradation when exposed to a humid atmosphere, which originates from hydrolysis. Herein, the function of the M atom in Li₃MX₆ was clarified by a series of Li₃Y_1-xIn_xCl₆ (0 ≤ x < 1). When the ratio of In³⁺ was increased, a gradual structural conversion from the hexagonal-closed-packed (hcp) anion arrangement to cubic-closed-packed (ccp) anion arrangement has been traced. Compared to hcp anion sublattice, the Li₃MX₆ with ccp anion sublattice reveals faster Li⁺ migration. The tolerance of Li₃Y_1-xIn_xCl₆ towards humidity is highly improved when the In³⁺ content is high enough due to the formation of hydrated intermediates. The correlations among composition, structure, Li⁺ migration, and humidity stability presented in this work provide insights for designing new halide-based SSEs.

Keywords: all-solid-state; anion sublattice; halide solid electrolyte; humidity; lithium-ion conductor.