An Exremely Lightweight Fuel Cell System Operating on Hydrogen and Air
Agency / Branch:
DOD / ARMY
Currently, a 300 watt fuel cell stack of bipolar design projects a power density of about 40 watts per kilogram of system, excluding fuel and fuel tankage. In contrast, a battery of identically performing fuel cells which uses the concept of a single sheet of electrolyte shared by all cells, can achieve about 250 watts per kilogram, a factor of six improved. The single sheet design is so much lighter because it does not require end-plates, cell frames and cell supports for proper sealing, electrical contact, and fluid porting. Using the single sheet fuel cell concept, a 300 watt fuel cell system with chemical hydride is projected to weigh 4.3 kg, well within the 5 kg goal set by the customer. This is a significant weight savings over a traditional bipolar stack at about 10.6 kg. The issue of Power to Weight Ratio has been rightfully prioritized as the vital driver for successful man-portable power supplies. Our past experience with smaller systems based on the proposed concept, teaches that success is based on the satisfactory resolution of design issues inter-relating more intricately than in bipolar stacks. We propose in Phase I to perform the necessary design studies of cell, stack, and system in which the issues of configuration, operating envelope, and robustness are addressed and solved to a confidence level warranting hardware development in Phase II.
Small Business Information at Submission:
Principal Investigator:Paul Childs
14 Spring Street Waltham, MA 02154
Number of Employees: