Abstract: A supercapacitor capable of withstanding SMT manufacturing conditions includes at least one pair of electrodes having a mixture of carbon particles preferably in a CMC binder on facing surfaces of the at least one pair of electrodes; a porous separator, preferably polyimide, positioned between the facing surfaces of the at least one pair of electrodes; and an electrolyte for wetting the separator wherein the electrolyte includes an ionic liquid, such as EMITSFI, and optionally a solvent such as PC, GBL or glutaronitrile.

Abstract: An electrolyte system suitable for use in an energy storage device (such as a supercapacitor), and energy devices which comprising the electrolyte system which is made up of an ionic liquid, such as Li or EMI TFSI and a stabilising amount of a stabilising additive. The stabilising additive preferably contains nitrile and or aromatic (benzene) groups, and may be advantageously benzonitrile, cinnamonitrile or succinonitrile. The stabilising additive stabilises the energy storage device against ESR rise and/or capacitance loss but does not adversely affect other performance characteristics of the ionic liquid.

Abstract: Electrolyte for use in an energy storage device such as a capacitor or supercapacitor which comprises a solvent (preferably propionitrile) and an ionic species (preferably methyltriethylammonium tetrafluoroborate). The electrolytes provide a low ESR rise rate, a high voltage and permit operation over a wide range of temperatures, which makes them beneficial for use in a range of energy storage devices such as digital wireless devices, wireless LAN devices, mobile telephones, computers, electrical or hybrid electrical vehicles.

Abstract: A supercapacitor capable of withstanding SMT manufacturing conditions comprising at least one pair of electrodes having a mixture of carbon particles preferably in a CMC binder on facing surfaces of the at least one pair of electrodes; a porous separator, preferably polyimide, positioned between the facing surfaces of the at least one pair of electrodes; and an electrolyte for wetting the separator wherein the electrolyte comprises an ionic liquid, such as EMITSFI, and optionally a solvent such as PC, GBL or glutaronitrile.

Abstract: A generally prismatic package (1) for an electrical device in the form of supercapacitive element (2) having an electrical property with a predetermined value. Package (1) includes an insulating element in the form of a generally rectangular-prismatic liquid crystal polymer (LCP) housing (3) for supporting element (2). More specifically, element (2) is mounted to the insulating element such that, following surface mounting of element (2) to a substrate, in the form of a printed circuit board (not shown), the electrical property remains within a predetermined tolerance.

Abstract: A supercapacitor (1) includes two like stacked supercapacitive cells (2, 3) that are connected to each other in series. A two-piece generally prismatic sealed package (4) defines an interior (5) to contain cells (2, 3). Package (4) includes a substantially planar access sidewall (6) having two spaced apart apertures (7, 8) extending from interior (5) to an exterior of the package. Sidewall (6) contains a liquid crystal polymer (LCP). A lead assembly, in the form of two spaced apart metal leads (9, 10) are electrically connected to cells (2, 3) respectively, and extend through respective apertures (7, 8) to allow external electrical connection to the cells.

Abstract: Electrolyte for use in an energy storage device such as a capacitor or supercapacitor which comprises a solvent (preferably propionitrile) and an ionic species (preferably methyltriethylammonium tetrafluoroborate). The electrolytes provide a low ESR rise rate, a high voltage and permit operation over a wide range of temperatures, which makes them beneficil for use in a range of energy storage devices such as digital wireless devices, wireless LAN devices, mobile telephones, computers, electrical or hybrid electrical vehicles.

Abstract: An electrode for an energy storage device, including a substrate of at least one metal that forms a native oxide layer; and a treated layer formed on the substrate from the native oxide layer, the treated layer having a resistance that is less than the resistance of a native oxide layer. In some embodiments, the treated layer possesses at least one of the following properties: includes one or more dopants, is thinner than the native oxide layer, has a carbon coating that is applied to the treated layer which improved adhesion characteristics, and others. Further, there is an energy storage device having two or more of such electrodes, wherein the device has a low initial ESR and/or a low ESR at various intervals. Moreover, disclosed is a low resistance metal including a substrate of at least one metal that forms a native oxide layer; and a treated layer formed on the substrate from the native oxide layer, the treated layer having a resistance that is less than the resistance of a native oxide layer.