15253results about "Hybrid capacitor electrodes" patented technology

Electrolytic capacitors having low equivalent series resistance and low leakage current are described. The electrolytic capacitors include a solid electrolyte layer of a conductive material in particular a conductive polymer, and an outer layer that includes binders, polymeric anions and conductive polymers (e.g., polythiophenes). Also described is a method of preparing electrolytic capacitors that involves forming the conductive polymer of the solid electrolyte layer in situ by means of chemical oxidative polymerization or electrochemical polymerization. Electronic circuits that include the electrolytic capacitors are also described.

Compositions are provided comprising aqueous dispersions of at least one polypyrrole and at least one colloid-forming polymeric acids at methods of making such compositions. The new compositions are useful in electronic devices including organic electronic devices such as organic light emitting diode displays, memory storage, electromagnetic shielding, electrochromic displays,and thin film transistors, field effect resistance devices.

A preferred embodiment of the present invention is a meso-porous nanocomposite material comprising: (A) nano-scaled graphene platelets, wherein each of the platelets comprises a sheet of graphite plane or multiple sheets of graphite plane, and the platelets have a thickness no greater than 100 nm (preferably smaller than 10 nm) and an average length, width, or diameter no greater than 10 μm (preferably smaller than 500 nm); and (B) an electrically conducting binder or matrix material attached or bonded to the platelets to form the nanocomposite material having liquid accessible pores, which provide a surface area greater than about 100 m2 / gm, preferably greater than 500 m2 / gm, and most preferably greater than 1000 m2 / gm. Also disclosed is a capacitor that includes at least an electrode comprising such a meso-porous nanocomposite material. A supercapacitor featuring such a nanocomposite exhibits an exceptionally high capacitance value.

A method for forming an electrolytic capacitor is disclosed. The method includes forming a conductive polymer coating by polymerizing a monomer in the presence of less than a stoichiometric amount of an oxidative polymerization catalyst. The present inventor has found that the use of less than the stoichiometric amount of the oxidative polymerization catalyst per mole of monomer can slow the polymerization of the monomer, creating oligomers that are shorter in length than if fully polymerized into a polymer. Without wishing to be bound by theory, it is believed that these shorter oligomers provide better penetration into the porous anode. Thus, the resulting conductive polymer layer can be more intimately positioned with respect to the anode. As a result, the formed capacitor can exhibit better performance.

The present invention concerns electrode materials capable of redox reactions by electrons and alkaline ions exchange with an electrolyte. The applications are in the field of primary (batteries) or secondary electrochemical generators, super capacitors and light modulating system of the super capacitor type.

The present invention relates to a supercapacitor, also known as an electrical double-layer capacitor or ultracapacitor, having electrode material comprising single-wall carbon nanotubes. The carbon nanotubes can be derivatized with functional groups. The electrode material is made by preparing a polymer-nanotube suspension comprising polymer and nanotubes, forming the polymer-nanotube suspension into a polymer-nanotube composite of the desired form, carbonizing the polymer-nanotube composite to form a carbonaceous polymer-nanotube material, and activating the material. The supercapacitor includes electrode material comprising activated carbonaceous polymer-nanotube material in contact with current collectors and permeated with an electrolyte, which may be either fluid or solid. In the case of a fluid or compressible electrolyte, an electrolyte-permeable separator or spacer is interposed between the electrodes to keep the electrodes from shorting. The supercapacitor made with electrodes comprising underivatized single-wall carbon nanotubes and polymer that has been carbonized and activated appears to operate as a non-Faradaic supercapacitor.

Disclosed is an electrode for an electrochemical energy storage device, the electrode comprising a self-supporting layer of a mixture of graphene sheets and spacer particles and / or binder particles, wherein the electrode is prepared without using water, solvent, or liquid chemical. The graphene electrode prepared by the solvent-free process exhibits many desirable features and advantages as compared to the corresponding electrode prepared by a known wet process. These advantages include a higher electrode specific surface area, higher energy storage capacity, improved or higher packing density or tap density, lower amount of binder required, lower internal electrode resistance, more consistent and uniform dispersion of graphene sheets and binder, reduction or elimination of undesirable effect of electrolyte oxidation or decomposition due to the presence of water, solvent, or chemical, etc.

The present invention provides a multi-component hybrid electrode for use in an electrochemical super-hybrid energy storage device. The hybrid electrode contains at least a current collector, at least an intercalation electrode active material storing lithium inside interior or bulk thereof, and at least an intercalation-free electrode active material having a specific surface area no less than 100 m2 / g and storing lithium on a surface thereof, wherein the intercalation electrode active material and the intercalation-free electrode active material are in electronic contact with the current collector. The resulting super-hybrid cell exhibits exceptional high power and high energy density, and long-term cycling stability that cannot be achieved with conventional supercapacitors, lithium-ion capacitors, lithium-ion batteries, and lithium metal secondary batteries.

The present invention provides an electrically conductive electrode comprising particles of an electroactive material and a conductive graphene polymer binder that bonds multiple particles of the electroactive material together, wherein the binder is in an amount of from 0.01% to 90% by weight based on the total electrode weight. Also provided are (a) a precursor solution or suspension to the graphene polymer binder for the electrode; (b) a paste containing electroactive particles and a graphene polymer dispersed in a liquid; (c) a method of producing the electrode from the precursor paste; and (d) an electrochemical cell (a battery or supercapacitor) containing such an electrode.

A power system adapted for supplying power in a high temperature environment is disclosed. The power system includes a rechargeable energy storage that is operable in a temperature range of between about seventy degrees Celsius and about two hundred and fifty degrees Celsius coupled to a circuit for at least one of supplying power from the energy storage and charging the energy storage; wherein the energy storage is configured to store between about one one hundredth (0.01) of a joule and about one hundred megajoules of energy, and to provide peak power of between about one one hundredth (0.01) of a watt and about one hundred megawatts, for at least two charge-discharge cycles. Methods of use and fabrication are provided. Embodiments of additional features of the power supply are included.

A polymer coated nanoparticle containing a metallic core and a polymer shell encapsulating said metallic core is useful, for example, in magnetic tapes and supercapacitors.

A process for producing meso-porous nanocomposite electrode comprising nano-scaled graphene platelets. The process comprises: (A) providing nano-scaled graphene platelets, wherein each of the platelets comprises a single graphene sheet or a stack of multiple graphene sheets, and the platelets have an average thickness no greater than 100 nm (preferably less than 5 nm and most preferably less than 2 nm in thickness); (B) combining a binder material, the graphene platelets, and a liquid to form a dispersion; (C) forming the dispersion into a desired shape and removing the liquid to produce a binder-platelet mixture; and (D) treating the binder material under a desired temperature or radiation environment to convert the binder-platelet mixture into a meso-porous nanocomposite electrode, wherein the platelets are bonded by the binder and the electrode has electrolyte-accessible pores characterized in that the nanocomposite has a surface area greater than about 100 m2 / gm (preferably greater than 200 m2 / gm, more preferably greater than 500 100 m2 / gm, and most preferably greater than 1,000 m2 / gm). A supercapacitor featuring such a nanocomposite exhibits an exceptionally high capacitance value.

The present invention relates to a supercapacitor, also known as an electrical double-layer capacitor or ultracapacitor, having electrode material comprising single-wall carbon nanotubes. The carbon nanotubes can be derivatized with functional groups. The electrode material is made by preparing a polymer-nanotube suspension comprising polymer and nanotubes, forming the polymer-nanotube suspension into a polymer-nanotube composite of the desired form, carbonizing the polymer-nanotube composite to form a carbonaceous polymer-nanotube material, and activating the material. The supercapacitor includes electrode material comprising activated carbonaceous polymer-nanotube material in contact with current collectors and permeated with an electrolyte, which may be either fluid or solid. In the case of a fluid or compressible electrolyte, an electrolyte-permeable separator or spacer is interposed between the electrodes to keep the electrodes from shorting. The supercapacitor made with electrodes comprising underivatized single-wall carbon nanotubes and polymer that has been carbonized and activated appears to operate as a non-Faradaic supercapacitor.

The invention features an electrode array (7) in which pairs of electrodes (1) are geometrically arranged so that the broadest faces of the exposed electrodes are not directly opposing to each other. Rather, the broadest facing surfaces of the electrodes in the array are parallel, adjacent, or offset at an angle. The electrode geometry of an electrode array of the invention permits electrodes to be in close proximity, thereby lowering series resistance, while minimizing the possibility for short circuits that can cause electrical leakage. An electrode array of the invention can be used in an electrochemical cell, such as a battery, e.g., a lithium battery, a capacitor, a flow-through capacitor, or a fuel cell.

The present invention is directed to the use of carbon nanotubes and / or electrolyte structures comprising ionic liquids in various electrochemical devices, such as ultracapacitors.