Insulative Ion-Conducting Lithium Selenide as the Artificial Solid-Electrolyte Interface Enabling Heavy-Duty Lithium Metal Operations

The deployment of Li metal batteries has been significantly tethered by uncontrollable lithium dendrite growth, especially in heavy-duty operations. Herein, we implement an in situ surface transformation tactic exploiting the vapor-phase solid-gas reaction to construct an artificial solid-electrolyte interphase (SEI) of Li2Se on Li metal anodes. The conformal Li2Se layer with high ionic diffusivity but poor electron conductivity effectively restrains the Li/Li+ redox conversion to the Li/Li2Se interface, and further renders a smooth and chunky Li deposition through homogenized Li+ flux and promoted redox kinetics. Consequently, the as-fabricated Li@Li2Se electrodes demonstrate superb cycling stability in symmetric cells at both high capacity and current density. The merits of inhibited dendrite growth and side reactions on the stabilized Li@Li2Se anode are further manifested in LiO2 batteries, greatly extending the cycling stability and energy efficiency.

Automated summary

The strategy of constructing an artificial solid-electrolyte interphase (SEI) of Li2Se on Li metal anodes through vapor-phase solid-gas reaction effectively inhibits lithium dendrite growth, resulting in superior cycling stability of the electrodes. Smooth and chunky Li deposition was achieved under high capacity and current density, while extending the cycling stability and energy efficiency of LiO2 batteries.