Cabana, Jordi Johnson, Christopher S. Yang, Xiao-Qing Chung, Kyung-Yoon Yoon, Won-Sub Kang, Sun-Ho Thackeray, Michael M. Grey, Clare P. 2024-01-20T19:00:34Z 2024-01-20T19:00:34Z 2021-09-05 2010-08 0884-2914 https://pubs.kist.re.kr/handle/201004/131218 The complexity of layered-spinel yLi(2)MnO(3)center dot(1-y)Li+xMn2-xO4 (Li:Mn = 1.2:1; 0 <= x <= 0.33; y >= 0.45) composites synthesized at different temperatures has been investigated by a combination of x-ray diffraction (XRD), x-ray absorption spectroscopy (XAS), and nuclear magnetic resonance (NMR). While the layered component does not change substantially between samples, an evolution of the spinet component from a high to a low lithium excess phase has been traced with temperature by comparing with data for pure Li1+xMn2-xO4. The changes that occur to the structure of the spinel component and to the average oxidation state of the manganese ions within the composite structure as lithium is electrochemically removed in a battery have been monitored using these techniques, in some cases in situ. Our Li-6 NMR results constitute the first direct observation of lithium removal from Li2MnO3 and the formation of LiMnO2 upon lithium reinsertion. English CAMBRIDGE UNIV PRESS LITHIUM-MANGANESE OXIDE X-RAY-DIFFRACTION CATHODE MATERIALS IN-SITU STRUCTURE REFINEMENT POSITIVE-ELECTRODE NMR LI2MNO3 MAS DIOXIDE Structural complexity of layered-spinel composite electrodes for Li-ion batteries Article 10.1557/JMR.2010.0206 1 JOURNAL OF MATERIALS RESEARCH, v.25, no.8, pp.1601 - 1616 JOURNAL OF MATERIALS RESEARCH 25 8 1601 1616 scie scopus 000280447400026 2-s2.0-77955960920 Materials Science, Multidisciplinary Materials Science Article LITHIUM-MANGANESE OXIDE X-RAY-DIFFRACTION CATHODE MATERIALS IN-SITU STRUCTURE REFINEMENT POSITIVE-ELECTRODE NMR LI2MNO3 MAS DIOXIDE lithium secondary batteries layered-spinel composite in situ XRD NMR