Cryo-EM snapshots of the solid-electrolyte interphase, or SEI, reveal its natural swollen state and offer a new approach to lithium-metal battery design

https://www6.slac.stanford.edu/news/2022-01-06-first-realistic-portraits-squishy-layer-that%E2%80%99s-key-battery-performance.aspx

"Cryo-EM is a form of electron microscopy... By flash-freezing their samples into a clear, glassy state, scientists can look at the cellular machines that carry out life’s functions in their natural state and at atomic resolution....sopping up the excess liquid with blotter paper... plunged into liquid nitrogen to freeze the little films into a glassy state that perfectly preserved the SEI... took place in a closed system that protected the films from exposure to air"

Related: Improving the durability of lithium metal batteries using carbon fiber paper as the anode

https://techxplore.com/news/2023-03-durability-lithium-metal-batteries-carbon.html