TEM Studies of Carbon Coated LiFePO4 after Charge DischargeCycling

Conference · Thu Nov 30 00:00:00 EST 2006

OSTI ID:902456

Gabrisch, H; Wilcox, J; Doeff, M

Carbon coating has proven to be a successful approach toimprove the rate capability of LiFePO4 used in rechargeable Li-ionbatteries. Investigations of the microstructure of carbon coated LiFePO4after charge discharge cycling shows that the carbon surface layerremains intact over 100 cycles. We find micro cracks in the cycledmaterial that extend parallel to low indexed lattice planes. Ourobservations differ from observations made by other authors. However thedifferences between the orientations of crack surfaces in both studiescan be reconciled considering the location of weak bonds in the unit celland specimen geometry as well as elastic stress fields ofdislocation.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE. Assistant Secretary for Energy Efficiency andRenewable Energy. Office of the Deputy Assistant Secretary for TechnologyDevelopment. Office of the FreeCAR and Vehicle TechnologiesProgram
• DOE Contract Number: DE-AC02-05CH11231
• OSTI ID: 902456
• Report Number(s): LBNL-62159; R&D Project: 500302; BnR: VT0301030; TRN: US200717%%339
• Resource Relation: Conference: 2006 Joint International Meeting of theElectrochemical Society and Congreso de la Sociedad Mexicana deElectroquimica, Cancun, Mexico, Oct 29-Nov. 3,2006
• Country of Publication: United States
• Language: English

Related Subjects

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CARBON
COATINGS
GEOMETRY
MICROSTRUCTURE