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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.
UNCLASSIFIED//F'iA. 'iFFllil,t.le lal!il!! 8111:!Y MCap nanocell 0.55μ~• Magnetic materials-----i____. Dielectric layer Magnetic materials _______r--* (all proprietary compositions) 1.sμm •I ------------------------------------------~ ---------------- MCap cell Made up of millions MCap nanocells Figure 12. MCap Structure. MCap nanocell and MCap cell are fabricated using traditional semiconductor fabrication processes. MCap cells are then packaged into larger MCap modules. The capacitance of the device is given by the equation , C = eo k A/d, where A is the area of the plate, d is the separation between plates, r.o the permittivity of free space, and k is the dielectric constant (or relative permittivity) of the material. The MCap increases capacitance by increasing the dielectric constant k through the GMC effect (fGMc) given by the relationship, k' = k*fGMc- GMC acts like a charge trap that brings electrons closer, thus increasing electron densities at the plates. Based on quantum theory, GMC brings about a capacitance which, to date, has been measured to be 109 times larger than that observed in electrostatic capacitors. As shown earlier in equation (2), energy is proportional to the capacitance and the voltage squared. Moreover, capacitor leakage and self-discharge are essentially eliminated as electrons are "trapped" in the magnetic field. Due to the above effects, the available energy for a large range of storage devices, like smart cards and other products, can be increased substantially by simply packaging them in series-parallel connected modules to meet the energy and voltage requirements. Coupled with Lockheed Martin's extensive nanomaterials and device physics experience, it is likely that NLSC will be able to use its MRAM development expertise to accomplish this. Experimental Results Over the last year, NLSC has had MCap structures and nanocells tested by independent parties with results shown in Figure 13. These unbiased tests demonstrate the validity of the high-capacitance claims. Figure 14 quantifies the progress in improved performance throughout the development of the device. The number of devices that demonstrate the GMC behavior has increased substantially in 2009, which is reportedly due to improved materials development rather than an increased production load. The performances of the nanocells as well as the variability are plotted, which shows that potential improvement in the materials could lead to an increased GMC factor. There is promising evidence that improvements may allow a higher level of performance, which could match lithium ion batteries at ambient temperature and perhaps exceed them at low and high temperatures. 22 UNCLASSIFIED//FQA: QFFIQIO k WEliii Qllk>f
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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.