Although being commercially realized, lithium-ion batteries are still the object of intense study aimed of further improving their electrochemical characteristics. The charge-discharge processes strongly depend on the crystal and electronic structure of the intercalation lithium-transition metal oxides used as cathode materials. Last years a great deal of attention was devoted to preparation of these compounds with unusual ordering (structural, magnetic, charge) and electronic state of transition metal ions, and a structure more stable to intercalation/deintercalation of lithium ions at discharge/charge processes, preventing a structural distortion and, thus, providing better electrochemical behavior. This can be achieved by a disordering of their structure. It was shown that the processes of disordering are followed by the processes of ordering of cations in these systems. For example, some authors showed that in the mixed lithium-manganese spinels LiMn_(2-x)Me_xO_4, where Me=Mg, Fe, the cation ordering in B-sites occurs. In the delithiated Li_(1-x)Mn_2O_4 and L_(1-x)CoO_2 the ordering of lithium vacancies was observed. While the processes of cation-cation long-range ordering occurring due to the interaction of d-electrons (long-range electron delocalization) are widely studied, the processes of short-range ordering (short-range delocalization) are poorly highlighted.
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