Multilayered Metal Insulation (MLMI) for Radioisotope Power System Designs

The Radioisotope Power Systems provide space power and energy storage that enable robotic spacecraft for exploration missions through our solar system. These systems must insulate hot parts from cold using advanced multilayered metal insulation (MLMI) that could reduce system losses. The conventional manufacturing method of MLMI suffers from poor insulative property, long lead time and high manufacturing costs due to manual position of standoffs between thin insulation layers (thickness of 100 micron with a target 100 micron gap). The challenge with achieving the targeted layer separation distance, layer thickness, control density and location of standoffs are critical aspects that effect the insulative property of MLMI. In Phase I, Faraday Technology and Physical Sciences, will address these challenges by demonstration of a manufacturing approach and thermal modelling to fabricate MLMI. Our current target for improved insulative properties is to decrease the thermal conductivity of MLMI from current value of 0.02 W/m·K to < 0.001 W/m·K. The proposed manufacturing approach will also reduce fabrication cost and lead time by combining additive manufacturing and electrochemical technologies to eliminate the manual application of standoffs. We will perform thermal analysis and develop thermal model to refine MLMI design. The Phase I results will be a platform from which Phase II would enable refinement of each manufacturing step and thermal model to improve the insulative properties of MLMI. We envision that by the end of the Phase II our team will develop a method such that completed MLMI packages for Radioisotope Power Systems will be fabricated and tested at NASA Glenn Research Center. In Phase III, we will work with commercialization partners and the NASA to transition and integrate this manufacturing method such that production costs and lead times for high performance MLMI can be further reduced.