FrancisAmalraj：弗兰西斯0amalraj

FrancisAmalraj：弗兰西斯0amalraj Structural Characteristics and Electrochemical Behavior of Lithium Rich Layered Materials as Cathodes for Advanced Batteries 11121Francis Amalraj, Daniel Sharon, Esthy Levy, Michael Talianker, Judith Grinblat, 11111Luba Burlaka, Gilead Shafir, Rachel Persky, Ella Zinigrad, Ortal Haik, 11Boris Markovsky, Doron Aurbach 1 - Department of Chemistry, Bar-Ilan University, Ramat-Gan, Israel 2 - Department of Materials Engineering and Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva, Israel .Lithiated oxides of the xLiMnO(1-x)Li[MnNiCo]O layered materials have attracted much 232 attention of the researchers in the field of advanced Li-ion batteries since they are interesting from both scientific and applied viewpoints. These oxides represent a type of layered LiMO compounds, 2 in which a transition metal M is partially substituted by structurally compatible LiMnO unit. 23 Electrodes based on these integrated materials can operate up to 4.6 – 4.8 V and provide reversible capacities >200 mAh/g at 1C rate. Using transmission electron microscopy examination and convergent micro-beam electron diffraction studies of these materials demonstrated that they are comprised of nano-domains of both rhombohedral LiNiO-like and monoclinic LiMnO structures, which are integrated and 223 interconnected with one another at the atomic level. It was shown that electrodes comprising the .0.5LiMnO0.5LiNiMnCoO submicron particles demonstrated higher capacity, a superior 231/31/31/32 cycling behavior at various charge/discharge rates and higher capacity retention in comparison with electrodes of compositions x=0.3 and x=0.7. We have established that the electrochemically 00"inactive" LiMnO can be activated by charging the electrodes at 30 and 60C. The electrochemical 23 activation of the LiMnO component by its decomposition to LiO and MnO at 4.5 V during first 23227lithium deintercalation was reflected by X-ray diffraction, Raman spectroscopy, and solid-state Li NMR testing of the electrodes. In this work, we studied also the transition metals dissolution during .cycling and analyzed gas evolution by charging Li/xLiMnO(1-x)Li[MnNiCo]O and Li/LiMnO cells. 23223 Some probable reactions that may occur at cathodes in ethylene carbonate-dimethyl carbonate/LiPF solutions at potentials >4.5 V were suggested. 6 Organized and Produced by: www.chemistry.org.il P.O.B 4034 Ness-Ziona 70400, Israel Tel: +972-8-931-3070, Fax: +972-8-946-0455] Site: www.bioforum.co.il E-mail: amir@bioforum.co.il