High Energy Density Lithium Rechargeable Batteries for Underwater Vehicle Propulsion

The rechargeable lithium/cobalt oxide electrochemistry is examined for its use in powering underwater vehicles. It has been successfully developed in 30 amp hour capacity cells. A comparative study with the silver oxide/zinc technology, most frequently used for this application, revealed lithium's superior performance. Lithium/cobalt oxide gave more charge-discharge cycles with 40–50% higher energy density. Lithium's advantage was especially marked at -2°C, where it cycled four times longer than silver cells. Projections indicate that, at the 600 amp hour cell size, the battery will have an energy density of 120 watt hours per pound resulting in a more durable and cost effective power source for naval vehicles than currently possible.