An electrode for an energy storage device includes carbon black particles having (a) a Brunauer-Emmett-Teller (BET) surface area ranging from 70 to 120 m.sup.2/g; (b) an oil absorption number (OAN) ranging from 180 to 310 mL/100 g; (c) a surface energy less than or equal to 15 mJ/m.sup.2; and (d) either an L.sub.a crystallite size less than or equal to 29 Å, or a primary particle size less than or equal to 24 nm.

The present patent application discloses a method of producing nano-porous carbon, comprising mixing furfuryl alcohol or its fast-polymerizing derivatives with an aluminum-based solid polymerization catalyst, heating the mixture until a solid catalyst-carbon matrix forms, heating again under inert atmosphere and etching the powder to remove the matrix to produce a network of pores in the nano-porous carbon. The application further provides a method for making of fabricating tailor-made nano-porous carbon electrodes.

The present invention provides an electrode material comprising at least one of metal compound powder and carbon powder, the powder having an average particle size of 50 μm or less and an activation energy E.sub.α of 0.05 eV or less. Further, the powder preferably has hopping conduction characteristics at room temperature of 25° C. Furthermore, the powder preferably has an amount of oxygen defects of 1×10.sup.18 cm.sup.−3 or more. Still further, the powder preferably has a carrier density of 1×10.sup.18 cm.sup.−3 or more. Due to above structure, there can be provided an electrode material having a high storage capacity and a high charge/discharge efficiency.

The present invention provides an electrode material comprising at least one of metal compound powder and carbon powder, the powder having an average particle size of 50 μm or less and an activation energy E.sub.α of 0.05 eV or less. Further, the powder preferably has hopping conduction characteristics at room temperature of 25° C. Furthermore, the powder preferably has an amount of oxygen defects of 1×10.sup.18 cm.sup.−3 or more. Still further, the powder preferably has a carrier density of 1×10.sup.18 cm.sup.−3 or more. Due to above structure, there can be provided an electrode material having a high storage capacity and a high charge/discharge efficiency.

An energy storage device can include a cathode, an anode, and a separator between the cathode and the anode, where the anode and/or electrode includes an electrode film having a super-fibrillized binder material and carbon. The electrode film can have a reduced quantity of the binder material while maintaining desired mechanical and/or electrical properties. A process for fabricating the electrode film may include a fibrillization process using reduced speed and/or increased process pressure such that fibrillization of the binder material can be increased. The electrode film may include an electrical conductivity promoting additive to facilitate decreased equivalent series resistance performance. Increasing fibrillization of the binder material may facilitate formation of thinner electrode films, such as dry electrode films.

An energy storage device can include a cathode, an anode, and a separator between the cathode and the anode, where the anode and/or electrode includes an electrode film having a super-fibrillized binder material and carbon. The electrode film can have a reduced quantity of the binder material while maintaining desired mechanical and/or electrical properties. A process for fabricating the electrode film may include a fibrillization process using reduced speed and/or increased process pressure such that fibrillization of the binder material can be increased. The electrode film may include an electrical conductivity promoting additive to facilitate decreased equivalent series resistance performance. Increasing fibrillization of the binder material may facilitate formation of thinner electrode films, such as dry electrode films.

Provided is a novel technique relating to electrochemical devices that makes it possible to ensure a high level of safety of an electrochemical device while also causing the electrochemical device to display excellent high-temperature storage characteristics. One or more composite particles for an electrochemical device each include a core particle and a shell portion at least partially covering an outer surface of the core particle. The core particle contains a melamine compound, and the shell portion contains an inorganic material.

Provided is an electrode-forming material for an electrochemical capacitor useful for forming an electrode of an electrochemical capacitor having a high storage capacity and a high energy density. The electrode-forming material for an electrochemical capacitor according to an embodiment of the present invention includes boron-doped nanodiamond (A) having a specific surface area of 110 m.sup.2/g or greater and an electrical conductivity at 20° C. of 5.0×10.sup.−3 S/cm or greater; and a metal oxide (B), and the content of the (B) is from 20 to 95 mass % with respect to the total content of the (A) and (B).

Provided is an electrode-forming material for an electrochemical capacitor useful for forming an electrode of an electrochemical capacitor having a high storage capacity and a high energy density. The electrode-forming material for an electrochemical capacitor according to an embodiment of the present invention includes boron-doped nanodiamond (A) having a specific surface area of 110 m.sup.2/g or greater and an electrical conductivity at 20° C. of 5.0×10.sup.−3 S/cm or greater; and a metal oxide (B), and the content of the (B) is from 20 to 95 mass % with respect to the total content of the (A) and (B).

A negative electrode active material for an electrochemical device which has improved quick charging characteristics. The negative electrode active material includes two types of graphite particles having a different particle diameter and shows a bimodal distribution, wherein the ratio of the average particle diameter (D.sub.50) of the first graphite particles to the average particle diameter (D.sub.50) of the second graphite particles is larger than 1.7.