Enhancing Moisture and Electrochemical Stability of the Li5.5PS4.5Cl1.5 Electrolyte by Oxygen Doping

Linfeng Peng; Shaoqing Chen; Chuang Yu; Chaochao Wei; Cong Liao; Zhongkai Wu; Hsing-Lin Wang; Shijie Cheng; Jia Xie

doi:10.1021/acsami.1c21561

Enhancing Moisture and Electrochemical Stability of the Li_5.5PS_4.5Cl_1.5 Electrolyte by Oxygen Doping

ACS Appl Mater Interfaces. 2022 Jan 26;14(3):4179-4185. doi: 10.1021/acsami.1c21561. Epub 2022 Jan 17.

Authors

Linfeng Peng^{1

2}, Shaoqing Chen³, Chuang Yu¹, Chaochao Wei¹, Cong Liao¹, Zhongkai Wu¹, Hsing-Lin Wang³, Shijie Cheng¹, Jia Xie¹

Affiliations

¹ State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
² School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
³ Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.

PMID: 35038866
DOI: 10.1021/acsami.1c21561

Abstract

Chlorine-rich argyrodite-type solid electrolyte Li_5.5PS_4.5Cl_1.5 has been a promising choice for solid-state batteries (SSBs) because of its ultrafast Li-ion conduction. However, the poor air/moisture stability and low electrochemical stability with pristine high-voltage cathodes hinder their applications. Herein, O-substituted Li_5.5PS_4.5-xO_xCl_1.5 (x = 0, 0.075, 0.175, and 0.25) solid electrolytes are successfully synthesized. Among them, Li_5.5PS_4.425O_0.075Cl_1.5 delivers high ionic conductivity, improved moisture resistance, and enhanced electrochemical stability in higher voltage windows. SSBs using Li_5.5PS_4.425O_0.075Cl_1.5 show higher capacities and superior cyclability than those using Li_5.5PS_4.5Cl_1.5 combined with a pristine LiNi_0.8Mn_0.1Co_0.1O₂ cathode when operated at a high end-of-charge voltage of 4.5 V (vs Li⁺/Li⁰). Moreover, the batteries exhibit outstanding performance in a wide temperature range. This work provides a strategy to modify the inherent drawbacks of sulfide electrolytes, promoting their practical applications.

Keywords: electrochemical performances; lithium argyrodites; oxygen doping; solid electrolyte; stability.