Dual-Function Carbon Composite Electrodes for Multifunctional Structural Sandwich Panels Incorporating Ultracapacitor Elements as Sandwich Core

Period of Performance: 09/26/2003 - 09/24/2005

$748K

Phase 2 SBIR

Recipient Firm

Boundless Corp.
2500 Central Avenue, Suite L
Boulder, CO 80301
Principal Investigator

Abstract

Boundless' innovative high-power multifunctional structural ultracapacitor, CapaciCoreTM, will increase high-power capabilities of advanced missile systems and HEVs. Dual-function carbon composite electrodes will integrate an activated carbon fabric face (high double-layer capacitance) with a non-porous, conductive matrix-impregnated carbon fabric face (high strength, improved current collection). Increased specific power and power density result because: + Electrically active high-surface-area carbon fibers extend partially into a conductive resin, forming a structural composite shell/bulk current collector with low resistance for increased power and reduced heat. + Distributed, corrugated, thermally conductive electrodes form cooling channels throughout a large volume, aiding thermal management. + Capacitor electrodes connect electrically in series at structural tie-points along corrugation apexes, forming higher-voltage assemblies with reduced current paths/interconnection resistance vs. traditional ultracapacitor packs. + Dual-function carbon composite electrodes increase current-collector-to-active-material ratio without increasing total mass. Effective capacitor mass is reduced by the mass of replaced inert structure. After optimizing electrodes for strength, capacitance and conductivity, we will integrate structural ultracapacitor cells with Boundless PowerCoreTM structural lithium-ion batteries into a high-power hybrid panel assembly, showing electrical performance can be tailored to match MDA requirements.