SBIR-STTR Award

This SBIR Phase I project will develop a lightweight, flexible, high-strength conductive wiring cable that is easy to process. In previous work, large volumetric fractions of Au, Ag, Cu and Al nanoparticles (NPs) were incorporated into a porous aramid nanofiber (ANF) matrix to realize films that have high electrical conductivity, yet maintain superior mechanical strength, the properties, which are usually hard to achieve simultaneously. Furthermore, the composite films demonstrate excellent flexibility, which is superior to other related classes of reported flexible conductors including carbon based nanomaterials (CNTs and graphene) and other metallic nanomaterials. The unique network structure enables high electrical conductivity and robust mechanical behavior of the metal-ANF films. Most pertinently for mass-restrictive applications, we demonstrated that copper-ANF composites had ~90 % less mass density than solid copper, but with electrical properties (conductivity, ampacity) that were at least 33 % of the bulk value. During Phase I, we will first find the lower limits of achievable mass that still provides acceptable conductivity, ampacity, and strength in both cylindrical and polygonal cross-sectional wires. We will then characterize the conductive and insulating properties of self-insulated wires, in which a single fabrication process can produce non-uniform conductivity with eleven orders of magnitude difference in the measured resistivity in different regions of the solid. Finally, we will design manufacturing tools to scale-up the production of wires and down-select to either a planar or cylindrical processing. Anticipated

Benefits:
The high-strength, reduced-mass conductor material is multi-use and cross-cutting for a broad range of NASA mission applications, whether that includes hybrid electric aeronautical craft or spacecraft. For space power applications, the innovation can be used for planetary surface power, large-scale spacecraft prime power, small-scale robotic probe power, and small-sat power. For aeronautical applications, the low-mass wiring can efficiently distribute power to aircraft propulsors with minimal mass overhead, such as in the STARC-ABL project. Lightweight metals can substantially impact the terrestrial electric vehicle and power-transmission markets. Energy storage systems must be flexible, robust, lightweight, and exhibit superior electrochemical activity. Furthermore, robust, flexible conductors are needed to meet the rapidly growing demand in smart sensors, roll-up displays, and other applications with unconventional form factors.