Characterization of AA size lithium rechargeable cells

Testing of AA size rechargeable cells for underwater vehicle and other naval applications is complete for AT&T´s lithium/niobium triselenide (Li/NbSe₃) and Moli Energy´s lithium/molybdenum disulfide (Li/MoS₂) and is in progress on Moli Energy´s lithium/manganese dioxide (Li/MnO₂) and W.R. Grace´s lithium/titanium disulfide (Li/TiS₂). Cell cycling was performed at various discharge rates, temperatures, and depths of discharge. At 25°C and 1 mA/cm² (roughly the C/4 rate), delivered energy densities were about 40 Wh/lb for NbSe₃, TiS ₂, and MnO₂ and 22 Wh/lb for MoS₂. Under the same conditions, nickel/cadmium (Ni/Cd) cells deliver only 10 Wh/lb. However Ni/Cd cycles much longer and the lithium cells are far more vulnerable than Ni/Cd to performance loss in low temperature, high discharge rate cycling. The NbSe₃ data and the (limited) TiS ₂ data indicate that these cells tend to accept excessive charge which is often associated with lithium dendrite shorting and considered potentially hazardous. At 1 mA/cm² and 25°C, discharge plateaus ranged from 2.9 V for MnO₂ to 1.8 V for MoS₂