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 m 2 /gm, preferably greater than 500 m 2 /gm, and most preferably greater than 1000 m 2 /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.

Nano-scaled graphene plate nanocomposites for supercapacitor electrodes

A method of producing a composite electrode having a specific surface area of at least 100 m2/gm for use in an electrochemical capacitor. The method comprises (a) providing exfoliated graphite flakes that are substantially interconnected to form a porous, conductive graphite network comprising pores; and (b) incorporating an electrochemically active material into at least a pore of the graphite network to form the composite electrode. The exfoliated graphite flakes are preferably obtained from the intercalation and exfoliation of a laminar graphite material selected from natural graphite, spheroidal graphite, synthetic graphite, highly oriented pyrolytic graphite, meso-carbon micro-bead, carbon/graphite fiber, carbon/graphite whisker, carbon/graphite nano-fiber, carbon nano-tube, or a combination thereof. A supercapacitor featuring such a composite electrode exhibits an exceptionally high capacitance value and low equivalent series resistance.

Method of producing graphite-carbon composite electrodes for supercapacitors

A dry process-based electro-chemical device and method for making a self-supporting dry electrode film for use therein is disclosed. Cost effective manufacture of electro-chemical devices such as batteries, capacitors, and fuel cells is enabled.

Dry particle based electro-chemical device and methods of making same

An active material powder mixture for batteries or a carbonaceous material powder mixture for electrical double-layer capacitors is composed of a battery active material or a carbonaceous material in combination with an electrically conductive powder that adheres to the periphery of the active material or carbonaceous material and has an average particle size of 10 nm to 10 μpm. The battery active material powder mixture may be used to make electrodes for secondary batteries. The carbonaceous material powder mixture may be used to make polarizable electrodes for electrical double-layer capacitors. Secondary cells produced using the active material powder mixture can lower an impedance of an electrode and operate at a high capacity and a high current, have a high rate property, and are thus well-suited for use as lithium secondary cells and lithium ion secondary cells. Electrical double-layer capacitors made using the carbonaceous material powder mixture have a high output voltage and a high capacity because of a low impedance.

Battery active material powder mixture, electrode composition for batteries, secondary cell electrode, secondary cell, carbonaceous material powder mixture for electrical double-layer capacitors, polarizable electrode composition, polarizable electrode, and electrical double-layer capacitor

Dry process based energy storage device structures and methods for using a dry adhesive therein are disclosed.

Dry-particle based adhesive and dry film and methods of making same

The present invention provides: a polarizable electrode for use in electric double-layer capacitor, which is made of a carbon composite material composed mainly of: 100 parts by weight of an activated carbon, 0.05 parts by weight of an amorphous carbon, 0.1-1,000 parts by weight of a conductive agent, and 0.03-90 parts by weight of a fibrillated carbon; and an electric double-layer capacitor comprising at least one pair of a positive electrode and a negative electrode each containing the above polarizable electrode and each impregnated with an electrolytic solution. The above polarizable electrode and electric double-layer capacitor are substantially free from the drawbacks of conventional polarizable electrodes and conventional electric double-layer capacitors, have a low internal resistance and a long life, and can be charged with or can discharge a large electric current of several amperes to several hundreds of amperes momentarily.

Polarizable electrode for electric double-layer capacitor, and electric double-layer capacitor using said polarizable electrode

PROBLEM TO BE SOLVED: To provide a polarizable electrode, for an electric double layer capacitor, which solves conventional faults, whose internal resistance is low, whose life is long and by which a large current at several to several hundreds A can be charged and discharged instantaneously and to provide an electric double layer capacitor using the polarizable electrode. SOLUTION: A polarizable electrode is featured so as to be formed of a carbon composite material having a composition in which 100 pts.wt. of active carbon, 0.5 to 90 pts.wt. of amorphous carbon, 0.1 to 100 pts.wt. of a conducting agent and 0.02 to 90 pts.wt. of fibrilar carbon are contained. In addition, an electric double layer capacitor is formed in such a way that the polarizable electrode is used as at least one set of a positive pole and a negative pole and that the polarizable electrode is impregnated with an electrolytic solution.

Osamu Hasegawa

Papers

Polarizable electrode for electric double-layer capacitor, and electric double-layer capacitor using said polarizable electrode

Polarizable electrode for electric double layer capacitor and electric double layer capacitor using the polarizable electrode