Abstract: A lithium secondary battery includes an electrode group and a nonaqueous electrolyte having lithium ion conductivity. A negative electrode includes a negative electrode current collector. The negative electrode current collector has a first surface facing an outward direction of winding of the electrode group and a second surface facing an inward direction of the winding of the electrode group. Lithium metal is deposited on the first surface and the second surface by charge. The negative electrode further includes first protrusions protruding from the first surface and second protrusions protruding from the second surface. A ratio A1X/A1 is greater than a ratio A2X/A2. A1X is a sum of projected areas of the first protrusions on the first surface. A1 is an area of the first surface. A2X is a sum of projected areas of the second protrusions on the second surface. A2 is an area of the second surface.

Abstract: A lithium secondary battery comprises an electrode group and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector has a first surface facing outward of winding of the electrode group and a second surface facing inward of the winding of the electrode group. At least the first surface or the second surface includes a first region and a second region that is closer to an innermost circumference of the winding of the electrode group than the first region. Protrusions include outer-circumference-side protrusions disposed on the first region and inner-circumference-side protrusions disposed on the second region. In at least the first surface or the second surface, a first area rate is larger than a second area rate.

Abstract: A method for manufacturing an electrochemical device includes the following steps: a step of preparing a positive electrode, the positive electrode including a first current collector and a positive electrode layer containing a conductive polymer; a step of preparing a negative electrode, the negative electrode including a second current collector and a negative electrode layer; and a step of sealing the positive electrode, the negative electrode, and an electrolytic solution in an exterior body. The step of preparing the positive electrode includes a step of holding the positive electrode in depressurized atmosphere and then introducing gas containing CO2 as a primary component into the depressurized atmosphere.

Abstract: A lithium metal secondary battery includes a positive electrode, a negative electrode, a separator, and a nonaqueous electrolyte. The positive electrode and the negative electrode are wound to form an electrode group. The positive and negative electrodes face each other with the separator between the positive and negative electrodes. The electrode group has a space for accommodating at least part of the nonaqueous electrolyte when fully discharged. X and Y satisfy 1.00?X/Y<1.20, where X is a calculated thickness of the lithium metal which is calculated from design capacity per unit area of the positive electrode, and Y is a virtual thickness of the space when the space is assumed to be formed only between the negative electrode and the separator.

Abstract: A method for manufacturing an electrochemical device includes the following steps: a step of preparing a positive electrode, the positive electrode including a first current collector and a positive electrode layer containing a conductive polymer; a step of preparing a negative electrode, the negative electrode including a second current collector and a negative electrode layer; and a step of sealing the positive electrode, the negative electrode, and an electrolytic solution in an exterior body. The step of preparing the positive electrode includes a step of holding the positive electrode in depressurized atmosphere and then introducing gas containing CO2 as a primary component into the depressurized atmosphere.

Abstract: A lithium secondary battery includes an electrode group and a nonaqueous electrolyte having lithium ion conductivity. A negative electrode includes a negative electrode current collector. The negative electrode current collector has a first surface facing an outward direction of winding of the electrode group and a second surface facing an inward direction of the winding of the electrode group. Lithium metal is deposited on the first surface and the second surface by charge. The negative electrode further includes first protrusions protruding from the first surface and second protrusions protruding from the second surface. A ratio A1X/A1 is less than a ratio A2X/A2. A1X is a sum of projected areas of the first protrusions on the first surface. A1 is an area of the first surface. A2X is a sum of projected areas of the second protrusions on the second surface. A2 is an area of the second surface.

Abstract: A lithium secondary battery comprises an electrode group and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector has a first surface facing outward of winding of the electrode group and a second surface facing inward of the winding of the electrode group. At least the first surface or the second surface includes a first region and a second region that is closer to an innermost circumference of the winding of the electrode group than the first region. Protrusions include outer-circumference-side protrusions disposed on the first region and inner-circumference-side protrusions disposed on the second region. In at least the first surface or the second surface, a first area rate is smaller than a second area rate.

Abstract: A lithium secondary battery comprises an electrode group and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector has a first surface facing outward of winding of the electrode group and a second surface facing inward of the winding of the electrode group. At least the first surface or the second surface includes a first region and a second region that is closer to an innermost circumference of the winding of the electrode group than the first region. Protrusions include outer-circumference-side protrusions disposed on the first region and inner-circumference-side protrusions disposed on the second region. A first average height of the outer-circumference-side protrusions is smaller than a second average height of the inner-circumference-side protrusions.

Abstract: A lithium secondary battery includes a wound electrode group and a lithium-ion conductive nonaqueous electrolyte. The wound electrode group includes a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode. The negative electrode includes a negative electrode current collector. The negative electrode current collector includes: a layer having a first surface facing outward of the winding of the electrode group and a second surface facing inward of the winding of the electrode group; first protrusions protruding from the first surface; and second protrusions protruding from the second surface. Lithium metal is deposited on the first surface and the second surface by charging. A second average height of the second protrusions is higher than a first average height of the first protrusions.

Abstract: A lithium secondary battery comprises an electrode group and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector has a first surface facing outward of winding of the electrode group and a second surface facing inward of the winding of the electrode group. At least the first surface or the second surface includes a first region and a second region that is closer to an innermost circumference of the winding of the electrode group than the first region. Protrusions include outer-circumference-side protrusions disposed on the first region and inner-circumference-side protrusions disposed on the second region. A first average height of the outer-circumference-side protrusions is larger than a second average height of the inner-circumference-side protrusions.

Abstract: A lithium secondary battery includes a wound electrode group and a lithium-ion conductive nonaqueous electrolyte. The wound electrode group includes a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode. The negative electrode includes a negative electrode current collector. The negative electrode current collector includes: a layer having a first surface facing outward of the winding of the electrode group and a second surface facing inward of the winding of the electrode group; first protrusions protruding from the first surface; and second protrusions protruding from the second surface. Lithium metal is deposited on the first surface and the second surface by charging. A first average height of the first protrusions is higher than a second average height of the second protrusions.

Abstract: A lithium secondary battery comprises an electrode group and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector has a first surface facing outward of winding of the electrode group and a second surface facing inward of the winding of the electrode group. At least the first surface or the second surface includes a first region and a second region that is closer to an innermost circumference of the winding of the electrode group than the first region. Protrusions include outer-circumference-side protrusions disposed on the first region and inner-circumference-side protrusions disposed on the second region. A first average height of the outer-circumference-side protrusions is smaller than a second average height of the inner-circumference-side protrusions.

Abstract: A lithium secondary battery comprises an electrode group and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector has a first surface facing outward of winding of the electrode group and a second surface facing inward of the winding of the electrode group. At least the first surface or the second surface includes a first region and a second region that is closer to an innermost circumference of the winding of the electrode group than the first region. Protrusions include outer-circumference-side protrusions disposed on the first region and inner-circumference-side protrusions disposed on the second region. In at least the first surface or the second surface, a first area rate is smaller than a second area rate.

Abstract: A lithium secondary battery comprises an electrode group and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector has a first surface facing outward of winding of the electrode group and a second surface facing inward of the winding of the electrode group. At least the first surface or the second surface includes a first region and a second region that is closer to an innermost circumference of the winding of the electrode group than the first region. Protrusions include outer-circumference-side protrusions disposed on the first region and inner-circumference-side protrusions disposed on the second region. In at least the first surface or the second surface, a first area rate is larger than a second area rate.

Abstract: A lithium secondary battery comprises an electrode group and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector has a first surface facing outward of winding of the electrode group and a second surface facing inward of the winding of the electrode group. At least the first surface or the second surface includes a first region and a second region that is closer to an innermost circumference of the winding of the electrode group than the first region. Protrusions include outer-circumference-side protrusions disposed on the first region and inner-circumference-side protrusions disposed on the second region. A first average height of the outer-circumference-side protrusions is larger than a second average height of the inner-circumference-side protrusions.

Abstract: A lithium secondary battery includes an electrode group and a nonaqueous electrolyte having lithium ion conductivity. A negative electrode includes a negative electrode current collector. The negative electrode current collector has a first surface facing an outward direction of winding of the electrode group and a second surface facing an inward direction of the winding of the electrode group. Lithium metal is deposited on the first surface and the second surface by charge. The negative electrode further includes first protrusions protruding from the first surface and second protrusions protruding from the second surface. A ratio A1X/A1 is less than a ratio A2X/A2. A1X is a sum of projected areas of the first protrusions on the first surface. A1 is an area of the first surface. A2X is a sum of projected areas of the second protrusions on the second surface. A2 is an area of the second surface.

Abstract: A lithium secondary battery includes an electrode group and a nonaqueous electrolyte having lithium ion conductivity. A negative electrode includes a negative electrode current collector. The negative electrode current collector has a first surface facing an outward direction of winding of the electrode group and a second surface facing an inward direction of the winding of the electrode group. Lithium metal is deposited on the first surface and the second surface by charge. The negative electrode further includes first protrusions protruding from the first surface and second protrusions protruding from the second surface. A ratio A1X/A1 is greater than a ratio A2X/A2. A1X is a sum of projected areas of the first protrusions on the first surface. A1 is an area of the first surface. A2X is a sum of projected areas of the second protrusions on the second surface. A2 is an area of the second surface.

Abstract: A lithium metal secondary battery includes a positive electrode, a negative electrode, a separator, and a nonaqueous electrolyte. The positive electrode and the negative electrode are wound to form an electrode group. The positive and negative electrodes face each other with the separator between the positive and negative electrodes. The electrode group has a space for accommodating at least part of the nonaqueous electrolyte when fully discharged. X and Y satisfy 1.00?X/Y<1.20, where X is a calculated thickness of the lithium metal which is calculated from design capacity per unit area of the positive electrode, and Y is a virtual thickness of the space when the space is assumed to be formed only between the negative electrode and the separator.

Abstract: A lithium secondary battery includes a wound electrode group and a lithium-ion conductive nonaqueous electrolyte. The wound electrode group includes a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode. The negative electrode includes a negative electrode current collector. The negative electrode current collector includes: a layer having a first surface facing outward of the winding of the electrode group and a second surface facing inward of the winding of the electrode group; first protrusions protruding from the first surface; and second protrusions protruding from the second surface. Lithium metal is deposited on the first surface and the second surface by charging. A second average height of the second protrusions is higher than a first average height of the first protrusions.

Abstract: A lithium secondary battery includes a wound electrode group and a lithium-ion conductive nonaqueous electrolyte. The wound electrode group includes a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode. The negative electrode includes a negative electrode current collector. The negative electrode current collector includes: a layer having a first surface facing outward of the winding of the electrode group and a second surface facing inward of the winding of the electrode group; first protrusions protruding from the first surface; and second protrusions protruding from the second surface. Lithium metal is deposited on the first surface and the second surface by charging. A first average height of the first protrusions is higher than a second average height of the second protrusions.