Insulative Ion-Conducting Lithium Selenide as the Artificial Solid–Electrolyte Interface Enabling Heavy-Duty Lithium Metal Operations
Yong Ma, Le Wei, Yuting Gu, Liang Zhao, Yixiang Jing, Qiaoqiao Mu, Yanhui Su, Xuzhou Yuan, Yang Peng, Zhao Deng
Abstract
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 Li–O2 batteries, greatly extending the cycling stability and energy efficiency.