A. L. Lipson, R. S. Ginder, and M. C. Hersam
Northwestern University and CEES EFRC
To enhance the performance and lifetime of lithium-ion (Li-ion) batteries, researchers require an improved understanding of the formation of the solid-electrolyte interphase (SEI) layer and the degradation mechanisms in battery electrodes at the nanometer scale. Researchers at the Center for Electrochemical Energy Science (CEES), a U.S. Department of Energy (DOE) Energy Frontier Research Center (EFRC), have developed a novel in situ technique using scanning ion conductance microscopy (SICM) to measure both the local Li-ion current and topography of battery electrodes. This technique uses a pipette pulled to an approximately 100-nm outer diameter to locally probe the Li-ion current flowing between the pipette and electrode, as shown schematically in Figure 1a. As a proof of principle, SICM is demonstrated on lithographically defined tin stripes on a copper thin film on glass as shown in Figure 1b and 1c. Furthermore, this technique has been used during electrochemical cycling to study phenomena such as solid electrolyte interphase (SEI) formation and electrode degradation. Overall, this work establishes the unique capabilities of SICM as an in situ tool for probing spatial inhomogeneities in topography and electrochemistry in battery electrodes, thus providing new characterization data that can inform ongoing efforts to understand and improve the capacity, lifetime, and safety of Li-ion battery technology. This work has been published as a cover article in the journal Advanced Materials.
A. L. Lipson, R. S. Ginder, and M. C. Hersam, “Nanoscale In Situ Characterization of Li-ion Battery Electrochemistry via Scanning Ion Conductance Microscopy,” Advanced Materials 23(47), 5613 –5617 (2011) (Cover).