Abstract: A method of charging a secondary battery, the battery including a positive electrode in which a lithium ion is stored during discharging and released during charging, a negative electrode in which a lithium metal deposits during charging and dissolves during discharging, and a non-aqueous electrolyte having a lithium ion conductivity, wherein the method includes a step of charging the secondary battery according to a first charging profile. In the secondary battery, a surface of the negative electrode is covered with a protection layer. In the first charging profile, charging starts from a first charging step in which charging is performed at a constant current with a first electric current density I1, and following the first charging step, a second charging step is performed in which charging is performed at a constant current with a second electric current density I2 that is larger than the first electric current density I1.

Abstract: A lithium secondary battery includes a positive electrode, a negative electrode disposed opposed to the positive electrode, a separator interposed between the positive electrode and the negative electrode, a non-aqueous electrolyte having a lithium ion conductivity, and a spacer interposed between the negative electrode and the separator. A lithium metal deposits on the negative electrode during charging, and the lithium metal dissolves from the negative electrode during discharging. The spacer has a net structure formed with a plurality of lined projected portions.

Abstract: A lithium secondary battery includes: a positive electrode that absorbs lithium ions during discharging and releases the lithium ions during charging; a negative electrode on which lithium metal is deposited during charging and from which the lithium metal dissolves during discharging; and a non-aqueous electrolyte that has lithium ion conductivity. A surface of the negative electrode is covered with a protective layer that contains a resin material and inorganic particles having a density of 6 g/cm3 or more.

Abstract: A lithium secondary battery includes a positive electrode, a negative electrode, a lithium ion conductive nonaqueous electrolyte, and a separator disposed between the positive electrode and the negative electrode. On the negative electrode, lithium metal deposits during charging, and the lithium metal is dissolved during discharging; the negative electrode includes a negative electrode current collector, and a plurality of layers stacked on the negative electrode current collector; the plurality of layers include a first layer, a second layer, and a third layer; of the first to third layers, the first layer is closest to the negative electrode current collector, and the third layer is farthest from the negative electrode current collector; the first layer contains a material capable of storing lithium ions; the second layer contains lithium metal, and the third layer has an insulation property and a lithium ion permeability.

Abstract: In a non-aqueous electrolyte secondary battery including a positive electrode, a negative electrode, and a non-aqueous electrolyte having lithium-ion conductivity, the solvent in the non-aqueous electrolyte includes a first ether compound represented by a general formula (1): R1-(OCH2CH2)n—OR2 in which R1 and R2 are independently an alkyl group with a carbon number of 1 to 5, and n represents 1 to 3; and a second ether compound having a fluorination rate of 60% or more and represented by a general formula (2): Ca1Mb1Fc1Od1(CF2OCH2)Ca2Hb2Fc2Od2 in which a1?1, a2?0, b1?2a1, b2?2a2, c1=(2a1+1)?b1, c2=(2a2+1)?b2, d?0, and d2?0. The proportion of a total amount of the first ether compound and the second ether compound in the solvent is 80 volume % or more.

Abstract: A lithium secondary battery includes a positive electrode, a negative electrode, a separator, and a nonaqueous electrolyte having lithium-ion conductivity. A negative electrode current collector includes a layer having a first surface and a second surface opposite to the first surface, first protrusions protruding from the first surface, and second protrusions protruding from the second surface. The first and second surfaces are surfaces on which lithium metal is deposited during charge. When viewed in a direction of a normal to the first surface, a total area of overlap between the first protrusions and the second protrusions is ½ or less of a total area of the first 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 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 lithium secondary battery includes a positive electrode, negative electrode, a separator, and a nonaqueous electrolyte having lithium-ion conductivity. The positive electrode contains a positive electrode active material containing lithium. The negative electrode faces the positive electrode. The separator is disposed between the positive and negative electrodes. The negative electrode includes a negative electrode current collector. The negative electrode current collector includes a layer having a first surface, and protrusions protruding from the first surface. The first surface is a surface on which lithium metal is deposited during charge. The protrusions do not divide the first surface into parts.

Abstract: Provided is a battery negative electrode material exhibiting both a merit of high specific capacity obtained by using Si, and a merit of high cycle durability obtained by using a non-graphitizable carbon material. Specifically, provided is a negative electrode material (1) of a battery that includes silicon material areas (10) made of a silicon material, and a carbon material area (20) made of a carbon material. The carbon material area (20) is formed in a surrounding area of the silicon material area (10), separated by a cavity (30) at least at a portion. In addition, an (002) average interlayer spacing d002 of the carbon material area (20) determined by powder X-ray diffraction is from 0.365 nm to 0.390 nm.

Abstract: A lithium secondary battery includes a positive electrode, a negative electrode, a separator, and a nonaqueous electrolyte having lithium-ion conductivity. The positive electrode contains a positive electrode active material containing lithium. The negative electrode faces the positive electrode. The separator is disposed between the positive and negative electrodes. The negative electrode includes a negative electrode current collector. The negative electrode current collector includes a layer and protrusions. The layer has a first surface on which lithium metal is deposited during charge. The protrusions protrude from the first surface. At least one of the protrusions includes a conductive material and an insulative material.

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. 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 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 negative electrode active material contains a graphite material represented by a formula CaxByC1-y, where x and y satisfy 0<x<0.2 and 2x?y?0.5.

Abstract: A negative electrode active material includes a plurality of layers and lithium located between the plurality of layers, each of the plurality of layers containing carbon and boron, and nitrogen or phosphorus, wherein a molar ratio of the boron to the carbon is more than 0.6.

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.