Abstract: An electrochemical device includes a positive electrode having a positive electrode material layer containing a conductive polymer doped with a first anion and a second anion, a negative electrode having a negative electrode material layer storing and releasing lithium ions, and a nonaqueous electrolytic solution having lithium ionic conductivity. The second anion is more easily dedoped from the conductive polymer than the first anion. At an end period of charge of the electrochemical device, a number of moles M1 of the first anion and a number of moles M2 of the second anion respectively doped in the conductive polymer satisfy a relationship of M1<M2. At an end period of discharge of the electrochemical device, a number of moles M3 of the first anion and a number of moles M4 of the second anion respectively doped in the conductive polymer satisfy a relationship of M3>M4.

Abstract: A positive electrode active material for an electrochemical device has a fiber shape or a grain-aggregate shape. The positive electrode active material includes an inner core part having a fiber shape or a grain-aggregate shape, and a superficial part covering at least part of the inner core part. The inner core part contains a first conductive polymer, and the superficial part contains a second conductive polymer that is different from the first conductive polymer.

Abstract: A method for manufacturing a positive electrode for a power storage device includes the steps of: preparing a current collector that includes a first region and a second region on a surface of the current collector, the first region having a carbon layer formed on the surface, the second region having the surface exposed; and forming a conductive polymer layer selectively on a surface of the carbon layer by immersing the current collector in an electrolytic solution containing a raw material monomer and then conducting electrolytic polymerization of the raw material monomer.

Abstract: A method for manufacturing a positive electrode for a power storage device includes the steps of: preparing a current collector that includes a first region and a second region on a surface of the current collector, the first region having a carbon layer formed on the surface, the second region having the surface exposed; and forming a conductive polymer layer selectively on a surface of the carbon layer by immersing the current collector in an electrolytic solution containing a raw material monomer and then conducting electrolytic polymerization of the raw material monomer.

Abstract: A positive electrode active material for an electrochemical device has a fiber shape or a grain-aggregate shape. The positive electrode active material includes an inner core part having a fiber shape or a grain-aggregate shape, and a superficial part covering at least part of the inner core part. The inner core part contains a first conductive polymer, and the superficial part contains a second conductive polymer that is different from the first conductive polymer.

Abstract: An electrochemical device includes a positive electrode having a positive electrode material layer containing a conductive polymer doped with a first anion and a second anion, a negative electrode having a negative electrode material layer storing and releasing lithium ions, and a nonaqueous electrolytic solution having lithium ionic conductivity. The second anion is more easily dedoped from the conductive polymer than the first anion. At an end period of charge of the electrochemical device, a number of moles M1 of the first anion and a number of moles M2 of the second anion respectively doped in the conductive polymer satisfy a relationship of M1<M2. At an end period of discharge of the electrochemical device, a number of moles M3 of the first anion and a number of moles M4 of the second anion respectively doped in the conductive polymer satisfy a relationship of M3>M4.