Documents / Report
This Defense Intelligence Reference Document from the Defense Intelligence Agency, dated 1 November 2010, was one of a series of advanced technology reports produced in FY 2010 under the Advanced Aerospace Weapons System Applications (AAWSA) Program. It reviews ultracapacitors as energy and power storage devices. It covers how they work, their materials, their commercial and military uses, and new developments such as carbon nanotubes, thin films and magnetic capacitors. It concludes that the U.S. government must understand and adopt advanced ultracapacitors.
“The Advance”13 pages
UNCLASSIFIED/ /P9Pl 8ffllilsl1k WE'lii QIU Y tuning the inner diameter may provide further enhancements. Figure 7 shows a vertically aligned CNT forest produced at Lockheed Martin's Advanced Technology Center (LMATC). Lockheed Martin has worked with a number of catalysts and surfaces to grow tailored CNT forests for a variety of applications. Select locations throughout Lockheed Martin have been developing CNT-based technologies, utilizing vertically aligned CNTs, CNTs dispersed onto surfaces, and CNTs dispersed into other media. LMATC possesses expertise in CNT growth processes and characterization and has capabilities for both materials development and ultracap testing. Lockheed Martin's NEARLab facility produces CNT-coated glass fibers, which may provide a cost-effective power storage solution that has structural elements built in. Ultracaps assembled from CNT forests appear extremely promising for use in microelectronics. Figure 7. CNT Forest. CNT forests grown in Lockheed Martin's laboratories can be tailored for specific sizes, lengths, and densities. Graphene is a relatively new discovery amongst carbonaceous materials. There are a number of types of graphene that can be characterized by the number of layers of graphene, the functionalization, or the oxidation status. Most graphene for ultracapacitor applications is going to be few-layer graphene and large-area flakes. The fewer the layers, the higher the active surface area will be. Single layer is ideal, but manufacturing considerations make single layer difficult, even at the laboratory scale. Functionalization will be directed toward improving capacitance or modifications to enable battery-like performance. Theoretical values of graphene indicate it could become an important material for the next generation of ultracapacitors. Graphene may be used as the sole electrode material, or it could be used as a conductive additive that also provides capacitance. The surface area is calculated to be as high as 2,600 m 2/g, the thermal conductivity is 5,000 W/m·K, and the charge carrier mobility is 200,000 cm 2/V·s. High surface area values and great conductivity are ideal properties for creating an electrode with very high capacitance and extremely favorable rate capabilities. Reported capacitances range from 135 to 205 F/g in aqueous electrolytes. 31 • 32 Figure 8 shows a transmission electron microscope image of graphene flakes used for ultra capacitor electrodes. These measurements come from few-layer graphene, rather than single layer, which suggest 18 UNCLASSIFIED//FQA Qffl8Itlit l!!l!H! &Ill I
Not linked to a story yet.
Report, from the dia collection. The PDF is mirrored here; the original link is above. 34 pages are in the text index: search them above, or from the library's search.