title: Observation and quantification of nanoscale processes in lithium batteries by operando electrochemical (S)TEM.
abstract: An operando electrochemical stage for the transmission electron microscope has been configured to form a "Li battery" that is used to quantify the electrochemical processes that occur at the anode during charge/discharge cycling. Of particular importance for these observations is the identification of an image contrast reversal that originates from solid Li being less dense than the surrounding liquid electrolyte and electrode surface. This contrast allows Li to be identified from Li-containing compounds that make up the solid-electrolyte interphase (SEI) layer. By correlating images showing the sequence of Li electrodeposition and the evolution of the SEI layer with simultaneously acquired and calibrated cyclic voltammograms, electrodeposition, and electrolyte breakdown processes can be quantified directly on the nanoscale. This approach opens up intriguing new possibilities to rapidly visualize and test the electrochemical performance of a wide range of electrode/electrolyte combinations for next generation battery systems.
authors.affiliation: Joint Center for Energy Storage Research, Fundamental and Computational Science Directorate, Pacific Northwest National Laboratory , Richland, Washington 99352, United States.
authors.forename: B L
authors.initials: BL
authors.lastname: Mehdi
authors.forename: J
authors.initials: J
authors.lastname: Qian
authors.forename: E
authors.initials: E
authors.lastname: Nasybulin
authors.forename: C
authors.initials: C
authors.lastname: Park
authors.forename: D A
authors.initials: DA
authors.lastname: Welch
authors.forename: R
authors.initials: R
authors.lastname: Faller
authors.forename: H
authors.initials: H
authors.lastname: Mehta
authors.forename: W A
authors.initials: WA
authors.lastname: Henderson
authors.forename: W
authors.initials: W
authors.lastname: Xu
authors.forename: C M
authors.initials: CM
authors.lastname: Wang
authors.forename: J E
authors.initials: JE
authors.lastname: Evans
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: J-G
authors.initials: JG
authors.lastname: Zhang
authors.forename: K T
authors.initials: KT
authors.lastname: Mueller
authors.forename: N D
authors.initials: ND
authors.lastname: Browning
keywords: Li batteries; Li dendrite formation; Li deposition/dissolution; Operando scanning transmission electron microscopy; SEI layer; in situ electrochemical liquid cell