Electrochemical intercalation of Li+ into nanodomain Li4Mn5O12

► Li4Mn5O12 with nanodomain structure and nanosized particles were obtained. ► Intercalation of Li+ in the spinels is controlled by the nanodomain structure. ► Interaction of the spinels with the electrolyte is a size-dependent process. ► Cycling stability is a result from the particle morphology.