Method for preparing spinel Li.sub.1+x MN.sub.2-x O.sub.4-Y intercalation compounds

A method of preparing a positive electrode for an electrochemical cell comprising:

• (a) mixing at least one manganese compound selected from the group consisting of manganese salts and oxides with at least one lithium compound selected from the group consisting of lithium salts and oxides in a lithium to manganese mole ratio of between about 1.02:2 and 1.1:2, wherein the manganese compound consists of particles having a mean particle diameter of between about 1 and 15 microns and the lithium compound has a smaller mean particle size than the manganese compound;
• (b) firing the mixture from the mixing step in one or more steps within specific temperatures ranges to form the spinel Li.sub.1+X Mn.sub.2-X O.sub.4+Y intercalation compound wherein at least one step is at a temperature of between about 700.degree. C. and 900.degree. C. for a soak time of at least about 10 hours;
• (c) dispersing the Li.sub.1+X Mn.sub.2-X O.sub.4+Y spinels in a solvent with a conductive agent and a binder material to form a slurry;
• (d) heating the slurry to evaporate the solvent to form a dry electrode;
• (e) compressing the dry electrode;
• and
• (f) cutting the dry electrode to form a positive electrode for an electrochemical cell.