HIGH ENERGY DENSITY CATHODES FOR RECHARGEABLE LITHIUM BATTERIES

A FEASIBILITY STUDY OF AN AMBIENT TEMPERATURE RECHARGEABLE LITHIUM BATTERY BASED ON THE LI/A-MOO(X)S(3)-X CHEMICAL COUPLE IS PROPOSED. IT IS ENVISIONED THAT, FULLY DEVELOPED, THIS BATTERY WILL PROVIDE A SPECIFIC ENERGY APPROACHING 300 WH/KG. IN THE PHASE I PROGRAM IT IS PROPOSED TO SYNTHESIZE AND CHARCTERIZE A NOVEL SET OF LI INSERTION MATERIALS, AMORPHOUS MOLYBDENUM OXYSULFIDES OF THE GENERAL FORMULA A-MOO(X)S(3)-X, DETERMINE THE ELECTRONIC CONDUCTIVITY OF THESE MATERIALS, AND ASSESS THEIR CATHODE CAPACITY USING WELL SPECIFIED, LABORATORY TEST CELLS. THE ELECTROLYTE WILL BE THF:2,ME-THF/LIASF(6), THE HIGHEST EFFICIENCY LI CYCLING SOLUTION PRESENTLY AVAILABLE TO USE OVER MOST OF THE MIL-SPEC TEMPERATURE RANGE. THE CELL TESTS WILL CONSIST OF CAPACITY DETERMINATION OVER A WIDE RANGE OF CURRENT DENSITIES FROM 0.5 THROUGH 8 MA/CM(2), AND GALVANOSTATIC AND POTENTIOSTATIC CYCLING. IT IS INTENDED THAT THIS PHASE I PROGRAM WILL ESTABLISH A STRONG FOUNDATION FOR A PHASE II PROGRAM, INVOLVING AN EXTENSIVE BATTERY DEVELOPMENT, BY ANSWERING BASIC QUESTIONS CONCERNING THE SUITABILITY OF THE MOLYBDENUM OXYSULFIDES FOR USE AS REVERSIBLE CATHODE MATERIALS IN LI CELLS.