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Widespread use of electric vehicles can have significant impact on urban air quality, national energy independence, and international balance of trade. An efficient battery is the key technological element to the development of practical electric vehicles. The science and technology of a nickel metal hydride battery, which stores hydrogen in the solid hydride phase and has high energy density, high power, long life, tolerance to abuse, a wide range of operating temperature, quick-charge capability, and totally sealed maintenance-free operation, is described. A broad range of multi-element metal hydride materials that use structural and compositional disorder on several scales of length has been engineered for use as the negative electrode in this battery. The battery operates at ambient temperature, is made of nontoxic materials, and is recyclable. Demonstration of the manufacturing technology has been achieved.

We discuss bias-induced threshold switching in chalcogenide-glass thin films, with an emphasis on the unique aspects of this phenomenon. The electronic nature of both the ON state and the recovery process is now clear. In this paper, we also establish the fundamentally electronic origin of the initiation process. An isothermal model is presented and analyzed for filamentary ON-state solutions via a set of phenomenological kinetic equations consistent with recent advances in our understanding of the electronic structure of chalcogenide glasses. The predictions of this model compare favorably with a variety of experimental results. The model is basically that the switching transition develops when a critical electric field is reached somewhere in the sample, usually near an electrode. Field-induced carrier generation then causes the charged traps in the bulk to fill (neutralize). When all the traps are filled, carriers can transit the sample with an enhanced mobility and the generation rate required to keep the traps filled is reduced from its threshold value.

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