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Title: Electron Microscopy Study of the LiFePO4 to FePO4 PhaseTransition

Abstract

The mechanism by which LiFePO4 is transformed intoisostructural FePO4 has been elucidated using electron microscopy onlarge, hydrothermally-grown LiFePO4 crystals following chemicaldelithiation. Lithium is extracted at narrow, disordered transition zoneson the ac crystal surface as the phase boundary progresses in thedirection of the a-axis. The substantial lattice mismatch along a (ca. 5percent) causes crack formation in the bc plane. Despite considerabledisorder in the transition zone, the general structural arrangement ispreserved, leading to good crystallinity in the newly created FePO4domains. Implications for improved electrode performance arediscussed.

Authors:
; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE. Assistant Secretary for Energy Efficiency andRenewable Energy. Office of the FreedomCAR and Vehicle TechnologiesProgram
OSTI Identifier:
903125
Report Number(s):
LBNL-59284
R&D Project: 674602; BnR: VT0301030; TRN: US200720%%91
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Electrochemical Society; Journal Volume: 9; Journal Issue: 6; Related Information: Journal Publication Date: 06/2006
Country of Publication:
United States
Language:
English
Subject:
25; ELECTRODES; ELECTRON MICROSCOPY; LITHIUM; PERFORMANCE; lithium batteries iron phosphate intercalationcompounds

Citation Formats

Chen, Guoying, Song, Xiangyun, and Richardson, Thomas J. Electron Microscopy Study of the LiFePO4 to FePO4 PhaseTransition. United States: N. p., 2006. Web.
Chen, Guoying, Song, Xiangyun, & Richardson, Thomas J. Electron Microscopy Study of the LiFePO4 to FePO4 PhaseTransition. United States.
Chen, Guoying, Song, Xiangyun, and Richardson, Thomas J. Fri . "Electron Microscopy Study of the LiFePO4 to FePO4 PhaseTransition". United States. doi:.
@article{osti_903125,
title = {Electron Microscopy Study of the LiFePO4 to FePO4 PhaseTransition},
author = {Chen, Guoying and Song, Xiangyun and Richardson, Thomas J.},
abstractNote = {The mechanism by which LiFePO4 is transformed intoisostructural FePO4 has been elucidated using electron microscopy onlarge, hydrothermally-grown LiFePO4 crystals following chemicaldelithiation. Lithium is extracted at narrow, disordered transition zoneson the ac crystal surface as the phase boundary progresses in thedirection of the a-axis. The substantial lattice mismatch along a (ca. 5percent) causes crack formation in the bc plane. Despite considerabledisorder in the transition zone, the general structural arrangement ispreserved, leading to good crystallinity in the newly created FePO4domains. Implications for improved electrode performance arediscussed.},
doi = {},
journal = {Journal of Electrochemical Society},
number = 6,
volume = 9,
place = {United States},
year = {Fri Jan 06 00:00:00 EST 2006},
month = {Fri Jan 06 00:00:00 EST 2006}
}
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  • No abstract prepared.