Lithium/titanium disulfide (Li/TiS2) cells are beingdeveloped for long life rechargeable applications. The effects ofcathode thickness, packing density, percent carbon, electrolyte type,and anode type on cycle life were evaluated. Cathode thickness was foundto have the most dramatic effect on cycle life, followed by cathodepacking density and electrolyte type. The cycle life of AA Li/TiS2 cells increased substantially as the cathode thickness decreased.At 100% depth of discharge (DOD), over 600 cycles have been demonstratedat 500 mA discharge and 125 mA charge rates. At 50% DOD, 830 cycles havebeen achieved. AA cells have been discharged at rates up to 2.0 A whilemaintaining over 60% cathode utilization. Microcalorimetry experimentshave been used to estimate a self-discharge rate of less than 1% permonth for cycled cells at 25° C. Safety testing indicates that freshcells do not vent when crushed or externally short circuited but mayvent after cycling. Heat tape tests showed that venting did not occurbelow 170° C
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