In-situ construction of a Mg-modified interface to guide uniform lithium deposition for stable all-solid-state batteries

• 作者: Tiefeng Liu Jiale Zheng Hualiang Hu Ouwei Sheng Zhijin Ju Gongxun Lu Yujing Liu Jianwei Nai Yao Wang Wenkui Zhang Xinyong Tao
• 来源期刊: 能源化学
• 年，卷（期）: 2021,（4）
• 页码范围: 272-278
• 页数: 7页
• 语种: 英文

摘要

Uniform lithium(Li)deposition in all-solid-state Li metal batteries is greatly influenced by the anode/electrolyte interface.Herein,a Mg-modified interface was constructed via the simple in-situ electrochem-ical reduction of Mg2+from Mg(TFSI)2 in polyethylene oxide(PEO)and a Li bis(trifluoromethane)sulfoni mide(LiTFSI)formulae.As confirmed by cryogenic transmission electron microscopy,the anode/electrolyte interface exhibited hybrids consisting of crystalline Mg,Li2O,and Li dots embedded in an amorphous polymer electrolyte.The crystalline Mg dots guided the uniform Li nucleation and growth,inducing a smoother anode/electrolyte interface compared with the pristine electrolyte.With 1 wt％Mg(TFSI)2 in the PEO-LiTFSI electrolyte,the Mg-modified electrolyte enabled the Li/Li symmetric cells with cycling performance of over 1700 and 1400 h at current densities of 0.1 and 0.2 mA cm-2,respec-tively.Moreover,the full LFP/Li cells using the novel Mg-modified electrolyte delivered a cycling lifespan of over 450 cycles with negligible capacity loss.