Design of Self-Wetting Interface between Garnet Solid Electrolyte and Lithium Metal Electrode

Haiquan Zhang,1# 

Houji Liu,1# 

Junping Mai,1# 

Yuxi Ren,1

Renjuan Wang,1

Xin Li,1

Qijiu Deng,1,2

Ning Wang1,Email

1State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University Haikou 570228, P.R. China

2International Research Center for Composite and Intelligent Manufacturing Technology, School of Materials Science and Engineering, Xi’an University of Technology, Xi’an, 710048, China

#These authors contributed to this work equally.

Abstract

Solid-state lithium metal batteries have emerged as promising energy storage systems due to large energy storage density and low-risk safety hazard. However, high-interface resistance between the garnet-based electrolyte and Li metal anode is one of the major challenges for all-solid-state batteries. Herein, a straightforward modification method is reported, rather than relying on hot pressing under an inert atmosphere or high-cost fabrication techniques to produce metastable nano-coating on garnet electrolyte surface. Fresh Li/Co@SSE@Co/Li batteries are placed at room temperature for 48 hours under a tiny pressure of 1 MPa, however the interfacial resistance between the garnet and Li metal reduces from 5,800 – 8,200 Ω cm2 to only 162 Ω cm2. At a current density up to 1.6 mA cm-2, the symmetrical batteries exhibit a stable signal voltage of about 190 mV. The maximum voltage fluctuation is less than 7 mV for the Li/Co@SSE@Co/Li batteries during 160 Li-striping/plating cycles at 0.25 mA cm-2. Excellent electrochemical performance and easy-to-industrial modification method are beneficial for the commercialization of Li metal all-solid-state batteries.

Design of Self-Wetting Interface between Garnet Solid Electrolyte and Lithium Metal Electrode