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发帖数: 43926 | 2 Atomic structure of sensitive battery materials and interfaces revealed by
cryo–electron microscopy
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Frozen in time
The electrochemical processes occurring in a battery are highly dynamic. To
understand the complexities of the charge and discharge cycles, you need to
be able to watch the processes in situ or to freeze the battery rapidly for
ex situ analysis. Li et al. applied cryo–electron microscopy techniques
commonly used for studying biological samples to examine batteries. They
identified the solid electrolyte interphase that forms, observed the
interactions of Li with the interphase, and captured the formation of
dendrites that can be detrimental to the lifetime of a battery.
Science, this issue p. 506
Abstract
Whereas standard transmission electron microscopy studies are unable to
preserve the native state of chemically reactive and beam-sensitive battery
materials after operation, such materials remain pristine at cryogenic
conditions. It is then possible to atomically resolve individual lithium
metal atoms and their interface with the solid electrolyte interphase (SEI).
We observe that dendrites in carbonate-based electrolytes grow along the <
111> (preferred), <110>, or <211> directions as faceted, single-crystalline
nanowires. These growth directions can change at kinks with no observable
crystallographic defect. Furthermore, we reveal distinct SEI nanostructures
formed in different electrolytes. |
