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arXiv · 1108.2326

Suppression of Phase Separation in LiFePO4 Nanoparticles During Battery Discharge

Peng Bai·Daniel A. Cogswell·Martin Z. Bazant
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Abstract

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.

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Peng Bai, Daniel A. Cogswell, Martin Z. Bazant. 2011-08-11. Suppression of Phase Separation in LiFePO4 Nanoparticles During Battery Discharge. https://doi.org/10.1021/nl202764f

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