nl5b00175_si_002.avi (43.8 MB)
Observation and Quantification of Nanoscale Processes in Lithium Batteries by Operando Electrochemical (S)TEM
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posted on 2015-03-11, 00:00 authored by B. L. Mehdi, J. Qian, E. Nasybulin, C. Park, D. A. Welch, R. Faller, H. Mehta, W. A. Henderson, W. Xu, C. M. Wang, J. E. Evans, J. Liu, J. -G. Zhang, K. T. Mueller, N. D. BrowningAn
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.