摘要
Lithiation-inducedplasticityisakeyfactorthatenablesSielectrodestomaintainlongcyclelifeinLi-ionbatteries.Westudytheplasticityofvariouslithiatedsili-conphasesbasedonfirst-principlescalculationsandiden-tifythelineardependenceoftheequivalentyieldstressonthehydrostaticpressure.Suchdependencemaycausethecompression-tensionasymmetryinanamorphousSithinfilmelectrodefromalithiationtodelithiationcycle,andleadstosubsequentratchetingoftheelectrodeaftercycliclithiation.Weproposeayieldcriterionofamorphouslithi-atedsiliconthatincludestheeffectsofthehydrostaticstressandthelithiationreaction.Wefurtherexaminethemicro-scopicmechanismofdeformationinlithiatedsiliconundermechanicalload,whichisattributedtotheflow-defectsmediatedlocalbondswitchingandcavitation.Hydrostaticcompressionconfinestheflowdefectsthuseffectivelystrength-enstheamorphousstructure,andviceversa.
出版日期
2013年03月13日(中国期刊网平台首次上网日期,不代表论文的发表时间)