Study on the stability of Li 2 MnSiO 4 cathode material in different electrolyte systems for Li-ion batteries
锂离子电池正极材料Li2MnSiO4在不同电解质体系中的稳定性研究
出版日期:2015
作者单位:aZentrumfürSonnenenergie-undWasserstoff-ForschungBaden-Württemberg,Helmholtzstr.8,89081Ulm,GermanybHelmholtz-InstitutUlm(HIU),Albert-Einstein-Allee11,89081Ulm,GermanycInstitutfürOberflächenchemieundKatalyse,UniversitätUlm,Albert-Einstein-Allee47,89081Ulm,GermanydKarlsruherInstitutfürTechnologie,Hermann-von-Helmholtz-Platz1,76344Eggenstein-Leopoldshafen,Germany杂志名称:Electrochimica Acta
卷号:176
期数:Complete
刊号:0013-4686
出版日期:2015
简介:Thisstudyreportsonthethoroughinvestigationintotheinteractionbetweennanosizedcarbon-coatedLi2MnSiO4andvariouselectrolytes,whichhasrevealedsignificantchangesoftheactivematerialaftersoakingintheelectrolyte.Apartfromthestandardelectrolytesaltlithiumhexafluorophosphate(LiPF6),lithiumbis(trifluoromethanesulfonyl)imide(LiTFSI)andtheF-freesaltlithiumbis-oxalatoborate(LiBOB)wereusedforsoakingtestsandcomparedintermsofcorrosionpowerwithLi2MnSiO4.Carbon-coatedLi2MnSiO4sampleswereobtainedbysolid-statesynthesisandstoredincontactwiththeelectrolyte.Theagedsampleswerefullycharacterizedbymeansofseveralanalyticaltechniques(XRD,XPS,SEM,ATR-FTIR).TheresultsshowthatLi2MnSiO4decomposesinLiPF6-basedelectrolyteathightemperatures,duetotheformationofHF,whichcausescorrosionofthematerialanddissolutionofMn.NodegradationwasobservedaftersoakingintheLiBOB-basedelectrolyte.Thecorrosionoftheactivematerialinstandardelectrolytesystem,togetherwithirreversiblestructuralchangesuponLielectrochemicalextraction,areconsideredasthemainreasonsforthepoorcapacityretentionuponcyclingoftheLi2MnSiO4-basedcathode.
