Size-dependent phase morphologies in LiFePO4 battery particles
Author(s)Cogswell, Daniel Aaron; Bazant, Martin Z
MetadataShow full item record
Lithium iron phosphate (LiFePO4) is the prototypical two-phase battery material whose complex patterns of lithium ion intercalation provide a testing ground for theories of electrochemical thermodynamics. Using a depth-averaged (a-b plane) phase-field model of coherent phase separation driven by Faradaic reactions, we reconcile conflicting experimental observations of diamond-like phase patterns in micron-sized platelets with observations of surface-controlled patterns in nanoparticles. Elastic analysis predicts this morphological transition for particles whose a-axis dimension exceeds twice the bulk elastic stripe period. We also simulate a rich variety of non-equilibrium patterns, influenced by size-dependent spinodal points and electro-autocatalytic control of thermodynamic stability.
DepartmentMassachusetts Institute of Technology. Department of Chemical Engineering; Massachusetts Institute of Technology. Department of Mathematics
Cogswell, Daniel A. and Martin Z. Bazant. "Size-dependent phase morphologies in LiFePO4 battery particles." Electrochemistry Communications 95 (October 2018): 33-37 © 2018 Elsevier B.V.