Patent ID: 7452630

Claim:
An electrochemical cell, comprising as at least part of an anode, a lithium transition metal oxide compound which has a [B 2 ]X 4 n− spinel-type framework structure of an A[B 2 ]X 4 stochiometric spinel or defect spinel wherein A comprises Li, B comprises Li and Ti, X is oxygen (O), and n− refers to the overall charge of the structural unit [B 2 ]X 4 of the framework structure, and the transition metal cation of which in the fully discharged state of the cell has a mean oxidation state greater than +3 for Ti, and further wherein the anode is further defined as comprising Li 4 Ti 5 O 12 , which can be written as (Li) 8a [Li 0.33 Ti 1.67 ] 16d O 4 in ideal spinel notation; as at least part of a cathode, a lithium metal oxide compound having a stochiometric spinel or defect spinel structure, any such a spinel structure having, as its basic structural unit, a unit of the formula [B 2 ]X 4 n− , where [B 2 ]X 4 n− is the structural unit of an A[B 2 ]X 4 spinel, with the X anions being arranged to form a negatively charged anion array, and wherein A comprises a lithium cation; B comprises at least two metal cations, of which one is manganese and the other is not manganese; X is oxygen (O); and n− refers to the overall charge of the structural unit [B 2 ]X 4 of the framework structure, with the transition metal cations of the anode being more electropositive than those of the cathode; and an electrically insulative, lithium containing, liquid or polymeric, ionically conductive electrolyte between the anode and the cathode, such that, on discharging the cell, lithium ions are extracted from the spinel-type framework structure of the anode, with the oxidation state of the metal ions of the anode thereby increasing, while a concomitant insertion of lithium ions into the compound of the cathode takes place, with the oxidation state of the metal ions of the cathode decreasing correspondingly.