POLYMER ELECTROLYTE FUEL CELL SYSTEMS FOR SPECIAL APPLICATIONS

摘要

Polymer electrolyte fuel cells (PEFC) have experienced significant interest for many applications over the last few decades, ranging from portable power generation in sub-watt to several hundred watts range, to automotive propulsion and stationary power generation. Due to lower noise and heat signature, portable PEFCs became the center of attention in mission critical systems, e.g. as a portable battery recharging system. PEFC systems present a unique alternative for portable power generation at around 200-500 W. Due to intrinsic compact design requirement, however, there are several challenges remaining to be tackled in the system level as well as the stack design and operation. Particularly, fuel storage for these systems still remains a challenge, as compressed or liquid hydrogen do not meet volume, weight and safety requirements. In addition, water management presents another issue since the amount of water that can be carried for humidification of the polymer electrolyte (i.e. polymer electrolyte membrane, PEM) is limited.