An electrochemical device of the present invention includes a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode. The positive electrode includes a positive current collector containing aluminum, a positive electrode material layer containing a conductive polymer, and an aluminum oxide layer disposed on a surface of the positive current collector. The aluminum oxide layer contains fluorine.

One aspect of the present invention is a nonaqueous electrolyte energy storage device including: a negative electrode containing a lithium alloy containing gold, and lithium metal; a positive electrode; and a nonaqueous electrolyte, in which the negative electrode includes a negative electrode substrate including a metal foil and a coating layer coating the negative electrode substrate, the metal foil contains copper, nickel, or stainless steel as a main component, and the coating layer contains gold as a main component.

Hybrid lithium-ion electrochemical cells include a first electrode having a first polarity and a first electroactive material that reversibly cycles lithium ions having a first maximum operational voltage and a second electrode having the first polarity with a second electroactive material having a second maximum operational voltage. A difference between the second and first maximum operational voltages defines a predetermined voltage difference. Also included are at least one third electrode including a third electroactive material that reversibly cycles lithium ions having a second polarity opposite to the first polarity, a separator, and electrolyte. A voltage modification component (e.g., diode) is in electrical communication with the first and the second electrodes. In a first operational state corresponding to charging, the at least one voltage modification component is configured to induce a voltage drop corresponding to the predetermined voltage difference providing high power density and high energy density hybrid lithium-ion electrochemical cells.

Disclosed herein is a method for using a high temperature rechargeable energy storage device comprising (a) obtaining an HTRESD; and (b) at least one of (1) cycling the HTRESD by alternatively charging and discharging the HTRESD at least twice over a duration of 20 hours and (2) maintaining a voltage across the HTRESD for 20 hours, such that the HTRESD exhibits a peak power density between 0.005 W/liter and 75 kW/liter after 20 hours when operated at an ambient temperature in an operating temperature range comprising between about −40° C. and about 210° C.

Disclosed herein is a method for using a high temperature rechargeable energy storage device comprising (a) obtaining an HTRESD; and (b) at least one of (1) cycling the HTRESD by alternatively charging and discharging the HTRESD at least twice over a duration of 20 hours and (2) maintaining a voltage across the HTRESD for 20 hours, such that the HTRESD exhibits a peak power density between 0.005 W/liter and 75 kW/liter after 20 hours when operated at an ambient temperature in an operating temperature range comprising between about −40° C. and about 210° C.

Disclosed are a method of manufacturing a flexible thin-film type super-capacitor device and a super-capacitor device manufactured by the same. The flexible thin-film type super-capacitor device comprises a base film which has flexibility; a separator which is interposed between the base films; and an active material which is formed on the base film. Thus, flexibility is given since thickness is very thin while maintaining high electrical conductivity and high binding property. In addition, economic feasibility is high and mass production is possible. Further, it is possible to stably and efficiently contain a highly corrosive material.

Disclosed are a method of manufacturing a flexible thin-film type super-capacitor device and a super-capacitor device manufactured by the same. The flexible thin-film type super-capacitor device comprises a base film which has flexibility; a separator which is interposed between the base films; and an active material which is formed on the base film. Thus, flexibility is given since thickness is very thin while maintaining high electrical conductivity and high binding property. In addition, economic feasibility is high and mass production is possible. Further, it is possible to stably and efficiently contain a highly corrosive material.

A lithium-cobalt-based composite oxide used for a positive electrode active material of an electrochemical device, wherein the lithium-cobalt-based composite oxide has elutable fluoride ions, the elutable fluoride ions being eluted to an eluate when the lithium-cobalt-based composite oxide is dispersed to ultrapure water, in a mass ratio of 500 ppm or more and 15000 ppm or less in comparison with the lithium-cobalt-based composite oxide, and the lithium-cobalt-based composite oxide has a composition shown by the following general formula (1): Li.sub.1-xCo.sub.1-zM.sub.zO.sub.2-aF.sub.a (−0.1≦x<1, 0≦z<1, 0≦a<2) . . . (1) (wherein, M represents one or more kinds of metal element selected from the group of Mn, Ni, Fe, V, Cr, Al, Nb, Ti, Cu, and Zn).

A lithium-cobalt-based composite oxide used for a positive electrode active material of an electrochemical device, wherein the lithium-cobalt-based composite oxide has elutable fluoride ions, the elutable fluoride ions being eluted to an eluate when the lithium-cobalt-based composite oxide is dispersed to ultrapure water, in a mass ratio of 500 ppm or more and 15000 ppm or less in comparison with the lithium-cobalt-based composite oxide, and the lithium-cobalt-based composite oxide has a composition shown by the following general formula (1): Li.sub.1-xCo.sub.1-zM.sub.zO.sub.2-aF.sub.a (−0.1≦x<1, 0≦z<1, 0≦a<2) . . . (1) (wherein, M represents one or more kinds of metal element selected from the group of Mn, Ni, Fe, V, Cr, Al, Nb, Ti, Cu, and Zn).

An electrochemical device electrode pertaining to one mode of the present invention has a current collector, an aluminum oxide layer, a conductive layer, and an active material layer. The current collector is an aluminum foil. The aluminum oxide layer is formed on a principle surface of the current collector and contains aluminum hydroxide and aluminum oxide. The conductive layer is formed on the aluminum oxide layer and contains conductive material, while the active material layer is formed on the conductive layer.