EXPERIMENTAL EVALUATION OF THE SYNTHETIC SOLID ELECTROLYTE INTERFACE CONCEPT FOR THE PRIMARY CA-SOCL2 BATTERY SYSTEM

THE CA-SOCL(2) BATTERY CHEMISTRY IS AN EXCELLANT CANDIDATE TO PROVIDE SAFE OPERATION IN BATTERIES SIGNIFICIANTLY LARGER THAN 1 KG OPERATE AT STEADY RATES GREATER THAN THE "C" RATE IN ARMY APPLICATIONS REQUIRING HIGH ENERGY DENSITY BATTERIES. PROGRESS HAS BEEN MADE ON OPTIMIZING THE ELECTROLYTE COMPOSITION AND THE CATHODE STRUCTURE TO MINIMIZE IR LOSSES AND MAXIMIZE CATHODE CAPACITY AT RELATIVELY HIGH SPECIFIC RATES (I.E. 20 MA/CM[2]). HOWEVER, THE TWIN PROBLEMS OF ANODE PASSIVATION AND ANODE CORROSION ARE ANTICIPATED IN THIS SYSTEM, PARTICULARLY FOR BATTERIES STORED AT ELEVATED TEMPERATURES AND/OR DISCHARGED AT LOW TEMPERATURES. WE PROPOSE TO DETERMINE AND DEMONSTRATE THE EFFICACY OF RD SPUTTERED SYNTHHETIC SOLID ELECTROLYTE INTERPHASE (SEI) COATINGS BASED ON THE TERNARY SYSTEM CA-GE-S AND RELATED CHEMISTRIES TO ALLEVIATE THESE PROBLEMS: REDUCING CA ANODE POLARIZATION AT HIGH DRAIN RATES AND REDUCING CA ANODE CORROSION AT ELEVATED TEMPERATURES.