Abstract: A container for a refrigerated fluid having an external container and an internal container between which an evacuated intermediate space is situated, which contains a superinsulator formed by several, separated layers of foil provided with a metal layer, is used as a storing device for electric energy. The foils act as foil capacitors and are electrically contacted so that an electric voltage can be applied to corresponding electric terminals on the exterior side of the container. In the container, a metal layer can be provided on both surfaces of the foil(s), and the foil(s) may consist of a material with a semiconductor characteristic. The foil capacitors are electrically connectable in series or parallel, and the electrical contacting of the foil metal surfaces can take place via a suspension structure of the internal container in the external container.

Abstract: A capacitive energy storage device is provided with specialized dielectric materials. In accordance with one embodiment of the present invention, a multilayer structure capacitive energy storage device is provided with a plurality of electrode layers and a plurality of dielectric layers. Respective ones of the dielectric layers are interposed between a selected pair of the plurality of electrode layers. The dielectric layers include a combination of materials as follows PbMgxNbyOz+SrTiO3.

Abstract: A capacitive energy storage device for use at cryogenic temperatures is provided including first and second electrode layers having a layer of dielectric material there between. The electrode layers include an electrically conductive material having a formula selected from YBa2Cu3Ox and Bi2Ca2Sr2Cu3Oy. A method of storing electrical charge in a capacitive energy storage device is also provided.