Lightweight High Specific Energy Power System for High Altitude Airships

The DoD has numerous space sensor and communications systems that are baselined for high altitude airships (HAA). These systems require continuous power for maintaining airship position and operating the sensor and communications systems. Because of the on-station time periods of the HAA of up to one year, on board stored fuel is not a feasible option for providing power to the HAA. Therefore, the best solution is the use of photovoltaics for energy collection coupled with a secondary battery for energy storage. Unfortunately, given current battery technology and the best available photovoltaics, the power subsystem mass would overwhelm the lift capacity of the HAA. Having a power subsystem tailored toward meeting the needs of the HAA that is scalable with specific energy densities of at least 2.0 kW-hr/kg is a realistic and necessary long term goal for the DoD. MSI together with Yardney/Lithion recognize the need to drastically increase the entire power subsystem's energy density to make HAA's a viable platform for the space based sensors. MSI is proposing to develop a HAA power system architecture consisting of thin film photovoltaics (TFPV) on a polymer substrate, a lithium-air battery, and power distribution electronics that can exceed 2000 W-hr/kg.