Cathode intercalation compositions, production methods and rechargeable lithium batteries containing the same

A method of preparing an intercalation composition having a spinel structure with crystallites of M2O3 dispersed throughout the spinel structure, said composition having the general formula

• Li1+xMyMn2−x−yO4
• wherein x is a number greater than 0 but less than or equal to 0.25, M is one or more trivalent metals, y is a number greater than 0 but less than or equal to 0.5, a portion of M is in said crystallites of M2O3 and said crystallites have a size less than about 1,000 Ångstroms, comprising the steps of:
• (a) intimately mixing particulate solid reactants comprised of lithium, manganese and one or more of said trivalent metals in the form of oxides, thermally decomposable salts or mixtures thereof in amounts based on said intercalation composition formula;
• (b) introducing the resulting intimately mixed reactants into a reactor;
• (c) heating the mixed reactants in the reactor in air or an oxygen enriched atmosphere at a temperature in the range of from about 550° C. to about 900° C. for a time period of up to about 48 hours;
• and
• (d) gradually cooling the reacted product formed in step (c) to a temperature of less than about 500° C.

An improved secondary rechargeable lithium battery comprised of a lithium ion receptive anode and a lithium intercalation cathode coupled together in an electrochemical cell housing by an electrolyte containing an electrolytically stable lithium salt, said lithium intercalation cathode being comprised of a composition having a spinel structure with crystallites of M2O3 dispersed throughout the structure, said composition having the general formula

• Li1+xMyMn2−x−yO4
• wherein:
• x is a number greater than 0 but less than or equal to 0.25;
• M is one or more trivalent metals;
• y is a number greater than 0 but less than or equal to 0.5;
• a portion of M is in said crystallites of M2O3;
• and said crystallites have a size of less than about 1,000 Ångstroms.