In Situ Scanning Electron Microscopy Characterization of the Mechanism for Li Dendrite Growth. Issue 8 (1st January 2016)

• Record Type: Journal Article
• Authors: Tang, Ching-Yen; Dillon, Shen J.
• Is Part Of: Journal of the Electrochemical Society. Volume 163:Issue 8(2016)
• Page Start: A1660
• Page End: A1665
• Publication Date: 2016-01-01
• Subjects: In-situ SEM -- Li-ion battery -- Lithium dendrites; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0891608jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : The nucleation and growth of Li metal deposits and whiskers were studied using a novel in-situ scanning electron microscopy (SEM) platform. The experiments utilized a thin carbon film as a substrate for Li deposition. Rather than depositing primarily at the carbon-electrolyte interface, much of the Li deposits at the carbon-vacuum interface. This allows the effects of concentration polarization and electric field localization to be eliminated as primary mechanisms for whisker and dendrite growth. Instead, measurements performed as a function of vacuum pressure reveal that whisker growth is sensitive to vacuum level. It is proposed that whisker growth results from diffusional relaxation of compressive stress imposed by a thin surface oxide. Similar mechanisms may be extended to Li dendrite growth in solution where solid electrolyte interphase introduces a compressive stress.