In Situ Observation of the Electrochemical Lithiation of a Single SnO 2 Nanowire Electrode

作者：Jian Yu Huang, Li Zhong, Chong Min Wang, J. P. Sullivan, Wu Xu, Liqiang Zhang, Scott X. Mao, Nicholas S. Hudak, Xiao Hua Liu, Arunkumar Subramanian, Hongyou Fan, Qi Liang, Akihiro Kushima, Ju Li · 发表于：Science · 年份：2010 · DOI：10.1126/science.1195628 · 被引用次数：1555 · 研究领域：Advancements in Battery Materials、ZnO doping and properties、Transition Metal Oxide Nanomaterials

We report the creation of a nanoscale electrochemical device inside a transmission electron microscope--consisting of a single tin dioxide (SnO(2)) nanowire anode, an ionic liquid electrolyte, and a bulk lithium cobalt dioxide (LiCoO(2)) cathode--and the in situ observation of the lithiation of the SnO(2) nanowire during electrochemical charging. Upon charging, a reaction front propagated progressively along the nanowire, causing the nanowire to swell, elongate, and spiral. The reaction front is a "Medusa zone" containing a high density of mobile dislocations, which are continuously nucleated and absorbed at the moving front. This dislocation cloud indicates large in-plane misfit stresses and is a structural precursor to electrochemically driven solid-state amorphization. Because lithiation-induced volume expansion, plasticity, and pulverization of electrode materials are the major mechanical effects that plague the performance and lifetime of high-capacity anodes in lithium-ion batteries, our observations provide important mechanistic insight for the design of advanced batteries.