Lithium Battery Research
Li Ion Battery Aging, Degradation, and Failure
Stephen J. Harris  sjharris(at)

Focused Ion Beam-Scanning Electron Microscope: FIB-SEM

James R. Wilson, J. Scott Cronin, Scott A. Barnett, and Stephen J. Harris, "Measurement of 3-dimensional microstructure in a LiCoO2 positive electrode"

LiCoO2 Particle #1 in 3 dimensions (3D) with a Focused Ion Beam (FIB)


Synchrotron NEW!


Diagnostic studies on NCA/Gr cells

Tortuosity of Porous Electrodes

Mechanics of Silicon Anodes

Nanoparticle Morphology Evolution

The Materials Project

Li Transport
in Graphite Electrode


Strain Maps

X-Ray Tomography

LiCoO2 Particle 1

Molecular Dynamics

Tin Oxide Nanowires

Neutron Imaging

Dendrites and Fracture


Publications by Stephen J Harris




A 3D image of the entire LiCo2 particle.


In this research on lithium battery durability, a three-dimensional serial-sectioning FIB-SEM (Focused Ion Beam-Scanning Electron Microscope) technique was used to reconstruct the microstructure of a fresh LiCoO2 positive electrode from a commercial Li-ion battery. Quantitative analyses revealed highly irregular particle shapes that included significant internal cracking, leading to reduced average Li diffusion lengths and higher surface areas than would be expected from spherical particles with the same volume fraction. Such internal cracks are often associated with battery aging, degradation, and failure. The cracks and grain boundaries observed with the focused ion beam could provide important routes for Li transport within the particles, in which case the commonly used shrinking core model would not be valid. We note that fractured particles usually are not associated with unused batteries, but we expect that changes in the microstructure can lead to lithium battery aging, degradation, and failure.