NASA’s Marshall Space Flight Center has developed a solid-state ultracapacitor utilizing a novel nanocomposite dielectric material. The material’s design is based on the internal barrier layer capacitance (IBLC) concept, and it uses novel dielectric and metallic conductive ink formulations.
Novel processing methods developed by NASA provide for unique dielectric properties at the grain level. Nanoscale raw material powders are tailored using a variety of techniques and then formulated into a special ink. This dielectric ink is used with novel metallic conductive ink to print a capacitor layer structure into any design necessary to meet a range of technical requirements.
The innovation is intended to replace current range safety batteries that NASA uses to power the systems that destroy off-course space vehicles. A solid-state design provides the needed robustness and safety for this demanding application.
The NASA solid-state ultracapacitor technology is based on the novel materials design and processes used to make the IBLC-type ultracapacitor. The IBLC concept is known to provide outstanding capacitance behavior, but has been difficult to reproduce. NASA has developed a careful process to produce dielectric ink materials to be used in printed electronic applications with reproducibility. An individual cell is created by building electrodes on each side of the dielectric layer, and complete modules can be constructed by stacking multiple cells.
Closely related NASA innovations on dielectric and conductive ink (electrode) formulations are key to the ultracapacitor construct, and are included in the technology package. Target performance criteria of
this technology include the following: use of standard materials and processing methods; robust, solid-state device with no liquid electrolytes; high energy density target of 60 J/cc at a minimum operating voltage of 50 V; high dielectric breakdown strength (>250 V); excellent pulse-power performance; rapid discharge and charge; and reliable performance under repeated cycling (>500,000 cycles). Additional development work is underway to build and test complete capacitor modules, and to further improve material properties and performance.
The technology has potential application in space power and propulsion systems; regenerative braking systems for cars, trucks, buses, and trains; batteries for hybrid and electric cars, as well as fuel cell-powered vehicles; smart grid and renewable energy systems; defense backup power supplies, laser weapons, and railguns; and medical devices.