Highly Conductive Composite Pressure Vessel Structures with Fire Resistance Properties

Several types of submersibles, including the Advanced SEAL Delivery System (ASDS), house batteries and associated electronics in externally mounted pressure vessels. As batteries are charged or discharged, heat builds up in the cells, increasing the chance of thermal runaway of a given cell. Standard composite materials are not highly efficient at transferring heat. A lightweight composite pressure vessel that would maximize the transfer of any heat developed by the battery and electronics from within a composite pressure vessel to the ambient environment (i.e. seawater) is needed to safely house these systems. The pressure vessel must be able to do this while maintaining sufficient structural strength to withstand external collapse pressures. k Technology, a division of Thermacore, proposes to develop a composite pressure vessel that will satisfy the program goals. This proposed vessel will be constructed of an innovative composite material with high thermal conductivity (>250 W/mK or >35X that of 6AL4V titanium), low mass density (< ½ of 6AL4V titanium), with stiffness and high strength properties equivalent to titanium. The proposed k Technology concept is to develop a high performance composite materials system which will provide both a highly conductive thermal path and structural protection for the encased battery system.