Lithium/liquid cathode for underwater vehicles

The lithium/liquid cathode systems appear particularly suitable for underwater vehicle propulsion because of high rate capabilities and long duration discharge associated with a high theoretical energy density. These properties led to the study of lithium/sulfuryl chloride batteries using Volta stack design with a flowing electrolyte. The authors present improvements of the electrochemistry of the systems and experimental results for batteries of up to 50 kW. This concept takes advantage of the possibility of thermal management by seawater cooling. Various cell designs using a Volta stack with an external diameter corresponding to that of a heavy weight torpedo have been tested. A Volta stack battery using a flowing electrolyte based on sulfuryl chloride gives a power output of up to 50 kW with a discharge duration of 20 min. Rate variations do not significantly modify the battery voltage. Optimized electrolyte, tested on a 10 kW battery, has shown improved capabilities for these systems