Advanced Regenerative Fuel Cell System for High-Altitude Airships

Next-Generation High-Altitude Airships (HAAs) are increasingly attractive for a variety of defense and non-defense oriented missions, including applications for homeland security, missile defense initiatives, surveillance, remote sensing, radar, and telecommunications. Providing adequate power for the airship and payloads is a prime concern for long-duration HAAs. Regenerative fuel cell (RFC) systems are a promising alternative to secondary batteries for power systems that must be lightweight, have a long cycle life and high reliability. In the Phase I program, Giner, Inc. demonstrated a unitized RFC having a round-trip efficiency of greater than 48% and developed a preliminary design for a closed-loop RFC system. The proposed Phase II program will significantly advance RFC technology by demonstrating a brassboard completely closed-loop RFC system with production and storage of hydrogen and oxygen at elevated pressure. The program will address the unique system design challenges for the HAA posed by the requirements for highly reliable, long-endurance operation.