Abstract: An electric double layer capacitor includes a first collector, a first polarizable electrode layer provided on the first collector, a second collector, a second polarizable electrode layer provided on the second collector and facing the first polarizable electrode layer, a separator having an insulating property and provided between the first polarizable electrode layer and the second polarizable electrode layer, and a driving electrolyte impregnated in the first polarizable electrode layer and the second polarizable electrode layer. The polarizable electrode layers mainly contain activated carbon made from phenol resin, have a surface roughness not larger than 0.6 ?m, and have an electrode density ranging from 0.5 g/cm3 to 0.7 g/cm3. This electric double layer capacitor has characteristics deteriorating little even at low temperatures, thus having a reliability for a long time.

Abstract: Activated carbon used for an electrochemical element in which when W1 and W2 satisfy 1.0 nm?W1<W2?2.0 nm, a total pore volume of the activated carbon in which a slit width obtained by an MP method is W1 or more and W2 or less is 15% or more of a total pore volume of the activated carbon in which the slit width obtained by the MP method is 2.0 nm or less. Furthermore, an electrode layer of the electrochemical element includes activated carbon having a large pore volume in which the slit width is W1 or more and W2 or less.

Abstract: The present invention provides an electrode material for an electric double layer capacitor which can provide an electric double layer capacitor having a low internal resistance and a large capacitance, a process for producing the same, and an electrode for an electric double layer capacitor and an electric double layer capacitor using the same. The electrode material of the present invention is characterized by comprising a carbonaceous material and an activated carbon, the carbonaceous material obtained by thermal-treating or activating a fullerene-containing soot or an extracted residue obtained by substantially extracting at least a part of fullerene from a fullerene-containing soot using a solvent. The electrode for an electric double layer capacitor and the electric double layer capacitor of the present invention is characterized by using the electrode material.

Abstract: Van der Waals molecular diameters of a cation, an anion, and a solvent contained in an electrolytic solution are denoted by Lc, La, and Ls, respectively. The minimum widths of van der Waals molecules of the cation, anion, and solvent are denoted by Lmin,c, Lmin,a, and Lmin,s, respectively. The maximum values of Lc, La, Ls, Lmin,c, Lmin,a, and Lmin,s is denoted by W1. The minimum values of (Lc+La), (Lc+Ls), (La+Ls), (Lmin,c+Lmin,a), (Lmin,c+Lmin,s), and (Lmin,a+Lmin,s) is denoted by W2. Under these definitions, the total pore volume of the activated carbon in which a slit width obtained by the MP method is W1 or more and W2 or less is 15% or more of the total pore volume in which the slit width is 2.0 nm or less.

Abstract: An electric double layer capacitor includes a positive electrode, a negative electrode which faces the positive electrode and is isolated therefrom, and an electrolyte solution. The positive electrode includes a first current collector of a metal foil and a first polarizable electrode layer on the first current collector, the first polarizable electrode layer containing a phosphorus compound. The negative electrode includes a second current collector of a metal foil and a second polarizable electrode layer on the second current collector. The electrolyte solution, with which the first and second polarizable electrode layers are impregnated, has fluorine-containing anions as an electrolyte solute.

Abstract: An electric double layer capacitor includes a first collector, a first polarizable electrode layer provided on the first collector, a second collector, a second polarizable electrode layer provided on the second collector and facing the first polarizable electrode layer, a separator having an insulating property and provided between the first polarizable electrode layer and the second polarizable electrode layer, and a driving electrolyte impregnated in the first polarizable electrode layer and the second polarizable electrode layer. The polarizable electrode layers mainly contain activated carbon made from phenol resin, have a surface roughness not larger than 0.6 ?m, and have an electrode density ranging from 0.5 g/cm3 to 0.7 g/cm3. This electric double layer capacitor has characteristics deteriorating little even at low temperatures, thus having a reliability for a long time.

Abstract: An electric double layer capacitor includes a positive electrode, a negative electrode which faces the positive electrode and is isolated therefrom, and an electrolyte solution. The positive electrode includes a first current collector of a metal foil and a first polarizable electrode layer on the first current collector, the first polarizable electrode layer containing a phosphorus compound. The negative electrode includes a second current collector of a metal foil and a second polarizable electrode layer on the second current collector. The electrolyte solution, with which the first and second polarizable electrode layers are impregnated, has fluorine-containing anions as an electrolyte solute.

Abstract: A polarizable electrode includes a collector and a polarizable electrode layer having a thickness of 5 ?m or more to 130 ?m or less on the surface of the collector. The polarizable electrode layer includes a first binder composed of at least one of an ammonium salt of carboxymethyl cellulose, polyvinylpyrrolidone, polyvinyl alcohol, methylcellulose, and a hydroxylpropyl cellulose resin, and a second binder composed of at least one of a latex, a fluoride-based polymer, a urethane resin, and an olefin-based resin. The content of the first binder is 5% by weight or less with respect to the total weight of the solid part, and the content of the second binder is 1% by weight or more and 5% by weight or less.

Abstract: The present invention provides an electrode material for an electric double layer capacitor which can provide an electric double layer capacitor having a low internal resistance and a large capacitance, a process for producing the same, and an electrode for an electric double layer capacitor and an electric double layer capacitor using the same. The electrode material of the present invention is characterized by comprising a carbonaceous material and an activated carbon, the carbonaceous material obtained by thermal-treating or activating a fullerene-containing soot or an extracted residue obtained by substantially extracting at least a part of fullerene from a fullerene-containing soot using a solvent. The electrode for an electric double layer capacitor and the electric double layer capacitor of the present invention is characterized by using the electrode material.