Using a novel electrochemical phase-field model, we question the common belief that LixFePO4 nanoparticles separate into Li-rich and Li-poor phases during battery discharge. For small currents, spinodal decomposition or nucleation leads to moving phase boundaries. Above a critical current density (in the Tafel regime), the spinodal disappears, and particles fill homogeneously, which may explain the superior rate capability and long cycle life of nano-LiFePO4 cathodes.
@article{arxiv.1108.2326,
title = {Suppression of Phase Separation in LiFePO4 Nanoparticles During Battery Discharge},
author = {Peng Bai and Daniel A. Cogswell and Martin Z. Bazant},
journal= {arXiv preprint arXiv:1108.2326},
year = {2015}
}