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Title: Enhanced Li-Ion Diffusivity of LiFePO 4 by Ru Doping: Ab Initio and Machine Learning Force Field Results
Ionic diffusivity plays a central role in battery performance. A cathode material for lithium-ion (Li-ion) batteries, LiFePO4 (LFP), performs poorly at high current rates due to low Li-ion diffusivity. An increase in ionic diffusivity is essential to enhance battery performance for high-power-density applications such as hybrid and electric vehicles. Here, we use molecular dynamics simulations with machine learning force field and climbing-image nudged elastic band calculations to show that Li-ion diffusivity in LFP increases when doped with the transition-metal dopant ruthenium. This increase is associated with a reduction in Li diffusion energy barrier, diffusion length, and Li-vacancy formation energy, and it is accompanied by changes in the electronic band structure, specifically the appearance of electronic states in the middle of the band gap and the vicinity of the conduction band.  more » « less
Award ID(s):
2052631
PAR ID:
10519082
Author(s) / Creator(s):
; ;
Corporate Creator(s):
Editor(s):
Lama, B; Smirnova, A; Paudel, T
Publisher / Repository:
ACS
Date Published:
Journal Name:
ACS Applied Energy Materials
Volume:
6
Issue:
20
ISSN:
2574-0962
Page Range / eLocation ID:
10424 to 10431
Subject(s) / Keyword(s):
LiFePO4 LFP doping-induced changes in conductivity ionic diffusivity nudged elastic band on-the-fly learning machine learning force field molecular dynamics
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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