DESIGN FOR THE COLD START-UP OF A MAN-PORTABLE FUEL-CELL AND HYDROGEN STORAGE-SYSTEM

The feasibility of developing a man-portable power supply having a maximum power of 500 W, a stored-energy capacity of 2000 W h and operating in environmental temperature conditions ranging from -40 to +40-degrees-C is explored. The design is based on combining an alkaline fuel cell stack and a hydrogen storage system that uses a chemical hydride. Two chemical hydrides, namely calcium hydride and lithium aluminum hydride are examined as possible storage media. The results indicate that the latter hydride would be some 25% lighter than the calcium hydride system, that the combined fuel cell and hydride system could be readily started and would function satisfactorily in an environment of -40-degrees-C. The power supply, based on the lithium aluminum hydride storage medium, would satisfy the required power specifications; the man-portable system would weigh approximately 3.4 kg with a volume of 13.2 1.