The present invention provides a thin film forming composition for energy storage device electrodes, said composition containing a conductive carbon material, a dispersant, a solvent and a polymer that has a partial structure represented by formula (P1) in a side chain. ##STR00001##
(In the formula, L represents —O— or —NH—; R represents an alkylene group having from 1 to 20 carbon atoms; T represents a substituted or unsubstituted amino group, a nitrogen-containing heteroaryl group having from 2 to 20 carbon atoms or a nitrogen-containing aliphatic heterocyclic group having from 2 to 20 carbon atoms; and * represents a bonding hand.)

The present invention provides a thin film forming composition for energy storage device electrodes, said composition containing a conductive carbon material, a dispersant, a solvent and a polymer that has a partial structure represented by formula (P1) in a side chain. ##STR00001##
(In the formula, L represents —O— or —NH—; R represents an alkylene group having from 1 to 20 carbon atoms; T represents a substituted or unsubstituted amino group, a nitrogen-containing heteroaryl group having from 2 to 20 carbon atoms or a nitrogen-containing aliphatic heterocyclic group having from 2 to 20 carbon atoms; and * represents a bonding hand.)

Electrode for storing electrical energy including a metal current collector and an active material, the current collector being coated on at least one portion of one of its faces with at least one protective layer placed between the current collector and the active material, the protective layer including: (A) a polymer matrix including: (A1) at least one cross-linked epoxy polymer or copolymer, (A2) at least one elastomer, and (B) conductive fillers. This system is used in aqueous electrolyte supercapacitors, the protective layer allowing a very significant reduction in corrosion problems that are generally associated with the use of aqueous electrolytes to be achieved and the adhesion of the active material to the metal collector to be improved.

An electrode current collector including a metal foil wherein a coating layer is formed on one or both surfaces of the metal foil, and a contact angle with pure water of the surface of the coating layer at a side opposite to the metal foil side is 30° or more.

A electric storage device that includes a device body having a first end face that has a first portion and a second portion, and second end face that has a third portion and a fourth portion. The second portion is inclined relative to the first portion, and the fourth portion is inclined relative to the third portion. A first electrode film extends from the first portion to the second portion, and a second electrode film extends from the third portion to the fourth portion.

As an electrode for a power storage device, an electrode including a current collector, a first active material layer over the current collector, and a second active material layer that is over the first active material layer and includes a particle containing niobium oxide and a granular active material is used, whereby the charge-discharge cycle characteristics and rate characteristics of the power storage device can be improved. Moreover, contact between the granular active material and the particle containing niobium oxide makes the granular active material physically fixed; accordingly, deterioration due to expansion and contraction of the active material which occur along with charge and discharge of the power storage device, such as powdering of the active material or its separation from the current collector, can be suppressed.

As an electrode for a power storage device, an electrode including a current collector, a first active material layer over the current collector, and a second active material layer that is over the first active material layer and includes a particle containing niobium oxide and a granular active material is used, whereby the charge-discharge cycle characteristics and rate characteristics of the power storage device can be improved. Moreover, contact between the granular active material and the particle containing niobium oxide makes the granular active material physically fixed; accordingly, deterioration due to expansion and contraction of the active material which occur along with charge and discharge of the power storage device, such as powdering of the active material or its separation from the current collector, can be suppressed.

An ultracapacitor that is in contact with a hot atmosphere having a temperature of about 80° C. or more is provided. The ultracapacitor contains a first electrode, second electrode, separator, nonaqueous electrolyte, and housing is provided. The first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating. The capacitor exhibits a capacitance value within the hot atmosphere of about 6 Farads per cubic centimeter or more as determined at a frequency of 120 Hz and without an applied voltage.

An ultracapacitor that is in contact with a hot atmosphere having a temperature of about 80° C. or more is provided. The ultracapacitor contains a first electrode, second electrode, separator, nonaqueous electrolyte, and housing is provided. The first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating. The capacitor exhibits a capacitance value within the hot atmosphere of about 6 Farads per cubic centimeter or more as determined at a frequency of 120 Hz and without an applied voltage.

An ultracapacitor that comprises a first and second electrochemical cell that are connected in parallel is provided. The cells are define by a first electrode that contains a current collector having opposing sides coated with a carbonaceous material, a second electrode that contains a current collector having opposing sides coated with a carbonaceous material, and a separator positioned between the first electrode and the second electrode. The second cell is by the second electrode, a third electrode that contains a current collector having opposing sides coated with a carbonaceous material, and a separator positioned between the second electrode and the third electrode. The ultracapacitor also contains a nonaqueous electrolyte that is in ionic contact with the electrodes and contains a nonaqueous solvent and an ionic liquid. A package encloses the first cell, the second cell, and the nonaqueous electrolyte.