In situ XRD and Li-6 MAS NMR spectroscopy have been carried out during the first charge process for the layered cathode material Li[Li1/9Ni3/9Mn5/9]O-2. In situ XRD results showed that the c-parameters of the Li[Li1/9Ni3/9Mn5/9]O-2 material increase only slightly at the end of charge. The Mn and Ni K-edge EXAFS results revealed that this compound contains localized clusters resembling the local environments found in Li2MnO3 and lithium nickel oxide. The Li-6 MAS NMR results showed the presence of Li in the Ni2+/Mn4+ layers, in addition to the expected sites for Li in the lithium layers. All the Li ions in the transition metal layers are removed on the first charge, leaving residual lithium ions in the lithium layers. (C) 2003 Elsevier Science B.V. All rights reserved.