Defect chemical aspects of lithium-ion battery cathodes

Structural and defect structural aspects of Lithiated layer-structured tran sition-metal oxides with the alpha-NaFeO2 structure will be discussed in re lation to stability and electrical behaviour. Emphasis will be put on anti- site disorder in LiNiO2. The defect structures of lithiated spinel-structur ed LiMn2O4 are quite dependent on the Li/Mn ratio and the dopants. Even def ect clusters have been proposed to occur in non-stoichiometric LiMn2O4. It will be shown that important information on the defect structures can be ob tained from magnetic and electron spin resonance (ESR) experiments on lithi um-deficient Li1-xMn2O4 and lithium-excess spinel Li1+dMn2-dO4. The number of unpaired electrons provides information on the distribution of electrons over the t(2g) and e(g) orbitals. The Curie temperature provides informati on on cation-cation and cation-anion-cation interactions. (C) 1999 Elsevier Science S.A. All rights reserved.