The nonaqueous electrolyte energy storage device according to an aspect of the present invention includes a negative electrode including graphite and graphitizable carbon, in which a ratio of a mass of the graphitizable carbon to a total mass of the graphite and the graphitizable carbon is less than 26% by mass, and a median diameter of the graphitizable carbon is smaller than a median diameter of the graphite.

A method of preparing an electrochemical electrode which is partially or totally covered with a film that is obtained by spreading an aqueous solution comprising a water-soluble binder over the electrode and subsequently drying same. The production cost of the electrodes thus obtained is reduced and the surface porosity thereof is associated with desirable resistance values.

A method of preparing an electrochemical electrode which is partially or totally covered with a film that is obtained by spreading an aqueous solution comprising a water-soluble binder over the electrode and subsequently drying same. The production cost of the electrodes thus obtained is reduced and the surface porosity thereof is associated with desirable resistance values.

An object of the present invention is to provide a carbonaceous material used for an electric double layer capacitor having a high electrostatic capacity and capable of maintaining the high electrostatic capacity and energy density over a long period and a method for producing the same. The present invention relates to a carbonaceous material having a specific surface area of 1,200 m.sup.2/g to 1,800 m.sup.2/g according to a BET method, an R-value of 1.2 or more and a G-band half-value width of 70 cm.sup.−1 or more according to a Raman spectrum.

An object of the present invention is to provide a carbonaceous material used for an electric double layer capacitor having a high electrostatic capacity and capable of maintaining the high electrostatic capacity and energy density over a long period and a method for producing the same. The present invention relates to a carbonaceous material having a specific surface area of 1,200 m.sup.2/g to 1,800 m.sup.2/g according to a BET method, an R-value of 1.2 or more and a G-band half-value width of 70 cm.sup.−1 or more according to a Raman spectrum.

A porous silicon-containing composite includes: a porous core including a porous silicon composite secondary particle; and a shell on at least one surface of the porous core, the shell including a first graphene, wherein the porous silicon composite secondary particle includes an aggregate of a first primary particle including silicon, a second primary particle including a structure and second graphene on at least one surface of the first primary particle and the second primary particle, and wherein at least one of a shape and a degree of oxidation of the first primary particle and the second primary particle are different. Also an electrode including the porous silicon-containing composite, a lithium battery including the electrode, and a device including the porous silicon-containing composite or the carbon composite.

An electrode assembly for an ultracapacitor is provided. The electrode assembly contains a first electrode comprising a first current collector electrically coupled to a first carbonaceous coating, a second electrode comprising a second current collector electrically coupled to a second carbonaceous coating, and a separator positioned between the first electrode and the second electrode. At least a portion of the first current collector projects beyond the first longitudinal edge to define a first projecting portion, wherein the offset ratio of the first projecting portion is from about 0.02 to about 0.3.

An electrode assembly for an ultracapacitor is provided. The electrode assembly contains a first electrode comprising a first current collector electrically coupled to a first carbonaceous coating, a second electrode comprising a second current collector electrically coupled to a second carbonaceous coating, and a separator positioned between the first electrode and the second electrode. At least a portion of the first current collector projects beyond the first longitudinal edge to define a first projecting portion, wherein the offset ratio of the first projecting portion is from about 0.02 to about 0.3.

An energy storage device can include a first electrode, a second electrode and a separator between the first electrode and the second electrode wherein the first electrode or the second electrode includes elemental lithium metal and carbon particles. A method for fabricating an energy storage device can include forming a first electrode and a second electrode, and inserting a separator between the first electrode and the second electrode, where forming the first electrode or the second electrode can include combining elemental lithium metal and a plurality of carbon particles.

An energy storage device can include a first electrode, a second electrode and a separator between the first electrode and the second electrode wherein the first electrode or the second electrode includes elemental lithium metal and carbon particles. A method for fabricating an energy storage device can include forming a first electrode and a second electrode, and inserting a separator between the first electrode and the second electrode, where forming the first electrode or the second electrode can include combining elemental lithium metal and a plurality of carbon particles.