AN ENERGY-DENSE HIGH-RATE POWER SUPPLY FOR ROBOTS

THE PROPOSED PROGRAM RELATES TO THE IDENTIFICATION OF A MIXED SOLVENT ELECTROLYTE CAPABLE OF EXTENDING THE POWER DENSITY, CYCLE LIFE AND USEFUL TEMPERATURE RANGE OF A LITHIUM SECONDARY BATTERY. CELLS WITH ELECTROLYTES CONTAINING A MIXTURE OF A CYCLIC ETHER AND AN ALKYL UREA WILL BE TESTED. THE MIXTURE HAS BEEN CHOSEN FOR EVALUATION BECAUSE INITIAL NMR DATA SHOWED THESE TWO SOLVENT TYPES TO HAVE CONSIDERABLE ELECTRON CLOUD OVER-LAP WHEN MIXED IN THE PROPER PROPORTIONS. SUCH OVER-LAP PROVIDES FOR HIGHER CHEMICAL STABILITY AND SOLUTE SOLVATION POWER. SUCCESSFUL COMPLETION OF THE PROGRAM WILL RESULT IN THE IDENTIFICATION OF A MIXED SOLVENT ELECTROLYTE WHICH PROVIDE AT LEAST 2 MA/CM 2 PERFORMANCE OVER A BROAD TEMPERATURE RANGE (-40 DEG TO +71 DEG C) OF A LITHIUM SECONDARY CELL) THE MIXTURE WILL ALSO SUPPORT EXTENDED CELL CYCLING ON STORAGE. THE PROGRAM APPROACH IS TO CARRY OUT CELL CYCLE TESTS OVER A BROAD TEMPERATURE RANGE. ELECTROLYTE DEGRADATION WILL BE FOLLOWED BY GC AND NMR; ANODE SURFACE CHARACTERISTICS WILL BE DETERMINED BY A TECHNIQUE BASED ON THE MEASUREMENT OF GAL VANOSTATIC TRANSIENTS. THE OPTIMIZED ELECTROLYTE MIXTURE WILL BE TESTED IN MULTIELECTRODE SEALED CELLS.