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dc.contributor.advisorAlamgir, Faisal
dc.contributor.authorPetersburg, Cole Fredrick
dc.date.accessioned2014-05-09T19:02:50Z
dc.date.available2014-05-09T19:02:50Z
dc.date.issued2012-01-11
dc.identifier.urihttp://hdl.handle.net/1853/51716
dc.description.abstractCurrently, automotive batteries use intercalation cathodes such as lithium iron phosphate (LiFePO4) which provide high levels of safety while sacrificing cell voltage and therefore energy density. Lithium transition metal oxide (LiMO2) batteries achieve higher cell voltages at the risk of releasing oxygen gas during charging, which can lead to ignition of the liquid electrolyte. To achieve both safety and high energy density, oxide cathodes must be well characterized under operating conditions. In any intercalation cathode material, the loss of positive lithium ions during charge must be balanced by the loss of negative electrons from the host material. Ideally, the TM ions oxidize to compensate this charge. Alarmingly, the stoichiometry of the latest LiMO2 cathode materials includes more lithium ions than the TM ions can compensate for. Inevitably, peroxide ions or dioxygen gas must form. The former mechanism is vital for lithium-air batteries, while the latter must be avoided. Battery researchers have long sought to completely characterize the intercalation reaction in working batteries. However, the volatile electrolytes employed in batteries are not compatible with vacuum-based characterization techniques, nor are the packaging materials required to contain the liquid. For the first time, a solid state battery (using exposed particles of Li1.17Ni0.25Mn0.58O2) was charged while using soft X-ray absorption spectroscopy to observe the redox trends in nickel, manganese and oxygen. This was combined with innovative hard X-ray absorption spectroscopic studies on the same material to create the most complete picture yet possible of charge compensation.en_US
dc.language.isoen_USen_US
dc.publisherGeorgia Institute of Technologyen_US
dc.subjectBatteryen_US
dc.subjectOperandoen_US
dc.subjectSynchotronen_US
dc.subjectNEXAFSen_US
dc.subjectEXAFSen_US
dc.subjectCharge compensationen_US
dc.subjectLithium batteriesen_US
dc.subjectLi-ionen_US
dc.subject.lcshLithium ion batteries
dc.subject.lcshCathodes
dc.subject.lcshOxidation
dc.titleNovel in operando characterization methods for advanced lithium-ion batteriesen_US
dc.typeDissertationen_US
dc.description.degreePh.D.
dc.contributor.departmentMaterials Science and Engineering
dc.embargo.termsnullen_US
thesis.degree.levelDoctoral
dc.contributor.committeeMemberCarter, Brent
dc.contributor.committeeMemberFuller, Thomas
dc.contributor.committeeMemberGerhardt, Rosario
dc.contributor.committeeMemberLiu, Meilin


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