Abstract: A lithium secondary battery includes: a positive electrode; a negative electrode; a separator disposed between the positive electrode and the negative electrode; and a nonaqueous electrolyte solution filled between the positive electrode and the negative electrode. The negative electrode includes: an electrically conductive layer having a surface; and lithium metal pieces arranged spaced from each other on the surface of the electrically conductive layer. There is no lithium metal on an imaginary line extending from a first end to a second end opposite to the first end of the surface of the electrically conductive layer and traversing a space between the lithium metal pieces.

Abstract: A positive electrode active material according to the present disclosure includes a lithium composite oxide that contains first particles having a crystal structure belonging to space group R-3m and second particles having a crystal structure belonging to space group C2/m. The crystal structure of the second particles has a larger amount of cation mixing than the crystal structure of the first particles. The second particles have a smaller particle size than the first particles. Mathematical Formula 0.05?integrated intensity ratio I(18°-20°)/I(43°-46°)?0.99 is satisfied. The integrated intensity ratio I(18°-20°)/I(43°-46°) is a ratio of the integrated intensity I(18°-20°) to the integrated intensity I(43°-46°). The integrated intensity I(A°-B°) is the integrated intensity of a maximum peak present in the range of angle of diffraction 2? greater than or equal to A° and less than or equal to B° in the X-ray diffraction pattern of the lithium composite oxide.

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: a positive electrode; a negative electrode including a negative electrode collector having a surface, on which a lithium metal is deposited during charge; a separator disposed between the positive electrode and the negative electrode; and a nonaqueous electrolyte solution filled between the positive electrode and the negative electrode. The negative electrode collector includes projection portions projecting from the surface toward the separator. There is no projection portion on an imaginary line extending from a first end to a second end opposite to the first end of the surface of the negative electrode collector and traversing a space between the projection portions.

Abstract: A positive electrode active material according to the present disclosure includes a lithium composite oxide that contains at least one element selected from the group consisting of F, Cl, N, and S, and at least one element selected from the group consisting of Bi, La, Ce, Ga, Sr, Y, and Sn. Mathematical formula 0.05?integrated intensity ratio I(18°-20°)/I(43°-46°)?0.90 is satisfied. The integrated intensity ratio I(18°-20°)/I(43°-46°) is a ratio of an integrated intensity I(18°-20°) to an integrated intensity I(43°-46°). The integrated intensity I(A°-B°)is an integrated intensity of a maximum peak present in a range of angle of diffraction 2? greater than or equal to A° and less than or equal to B° in the X-ray diffraction pattern of the lithium composite oxide.

Abstract: A positive electrode active material includes a lithium composite oxide having a crystal structure belonging to the space group Fd-3m and has an integrated intensity ratio I(18°-20°)/I(43°-46°) of greater than or equal to 0.05 and less than or equal to 0.90 and an integrated intensity ratio I(63°-65°)/I(17°-19°) of greater than or equal to 0.8 and less than or equal to 2.0. The integrated intensity ratio I(18°-20°)/I(43°-46°) is a ratio of an integrated intensity I(18°-20°) to an integrated intensity I(43°-46°). The integrated intensity ratio I(63°-65°)/I(17°-19°) is a ratio of an integrated intensity I(63°-65°) to an integrated intensity I(17°-19°). The integrated intensity I(A°-B°) is an integrated intensity of a maximum peak present in a range of angle of diffraction 2? greater than or equal to A° and less than or equal to B° in the X-ray diffraction pattern of the positive electrode active material.

Abstract: A positive electrode active material includes a first lithium composite oxide and a second lithium composite oxide that covers at least a part of the surface of the first lithium composite oxide. The first lithium composite oxide includes at least one selected from the group consisting of F, Cl, N, and S. The first lithium composite oxide has a crystal structure belonging to a layered structure. The second lithium composite oxide has a crystal structure belonging to space group Fd-3m. The positive electrode active material has an integrated intensity ratio I(18°-20°)/I(43°-46°) of greater than or equal to 0.05 and less than or equal to 0.90.

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 positive electrode active material includes a lithium composite oxide and a covering material that covers a surface of the lithium composite oxide. The covering material has an electron conductivity of 106 S/m or less. The lithium composite oxide is a multiphase mixture including a first phase having a first crystal structure that belongs to a space group Fm-3m and a second phase having a second crystal structure that belongs to a space group other than a space group Fm-3m. The ratio I(18°-20°)/I(43°-46°) of a first integrated intensity I(18°-20°) of a first maximum peak present at a first diffraction angle 2? of 18° or more and 20° or less to a second integrated intensity I(43°-46°) of a second maximum peak present at a second diffraction angle 2? of 43° or more and 46° or less in an XRD pattern of the lithium composite oxide satisfies 0.05?I(18°-20°)/I(45°-46°)?0.90.

Abstract: A positive electrode active material according to the present disclosure includes a lithium composite oxide that is a multiphase mixture including a first phase having a crystal structure belonging to a monoclinic crystal (e.g., space group C2/m), a second phase having a crystal structure belonging to a hexagonal crystal (e.g., space group R-3m), and a third phase having a crystal structure belonging to a cubic crystal (e.g., space group Fm-3m or space group Fd-3m). In addition, a battery according to an aspect of the present disclosure includes a positive electrode containing the positive electrode active material, a negative electrode, and an electrolyte. The positive electrode active material according to the present disclosure improves the capacity of the battery.

Abstract: A positive electrode active material according to the present disclosure includes a lithium composite oxide. The lithium composite oxide is a multiphase mixture including a first phase having a crystal structure belonging to space group C2/m and a second phase having a crystal structure belonging to space group R-3m and includes at least one selected from the group consisting of F, Cl, N, and S. In an XRD pattern of the lithium composite oxide, the integrated intensity ratio I(20°-23°)/I(18°-20°) of a second maximum peak present in a diffraction angle 2? range of greater than or equal to 20° and less than or equal to 23° to a first maximum peak present in a diffraction angle 2? range of greater than or equal to 18° and less than or equal to 20° satisfies 0.05?I(20°-23°)/I(18°-20°)?0.26.

Abstract: A positive electrode active material according to the present disclosure includes: a lithium composite oxide which contains Mn and at least one selected from the group consisting of F, Cl, and N, and S. The lithium composite oxide has a crystalline structure which belongs to a layered structure, and a relationship 0.95?intensity ratio IMn1/IMn2?1.75 is satisfied. The intensity ratio IMn1/IMn2 is a ratio of an intensity IMn1 to an intensity IMn2. The intensity IMn1 is an intensity of a first proximity peak of the Mn in a radial distribution function of the Mn contained in the lithium composite oxide. The intensity IMn2 is an intensity of a second proximity peak of the Mn in the radial distribution function of the Mn contained in the lithium composite oxide.

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. 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 positive-electrode active material contains a compound that has a crystal structure belonging to a space group FM3-M and contains is represented by the composition formula (1) and an insulating compound, LixMeyO?F???(1) wherein Me denotes one or two or more elements selected from the group consisting of Mn, Co, Ni, Fe, Al, B, Ce, Si, Zr, Nb, Pr, Ti, W, Ge, Mo, Sn, Bi, Cu, Mg, Ca, Ba, Sr, Y, Zn, Ga, Er, La, Sm, Yb, V, and Cr, and the following conditions are satisfied. 1.7?x?2.2 0.8?y?1.3 1???2.5 0.

Abstract: A positive-electrode active material containing a compound that has a crystal structure belonging to the space group FM-3M and is represented by the composition formula (1): LixMeyO?F???(1) wherein Me denotes one or two or more elements selected from the group consisting of Mn, Co, Ni, Fe, and Al, and the following conditions are satisfied. 1.3?x?2.2, 0.8?y?1.3, 1???2.93, 0.07???2.

Abstract: A positive-electrode active material contains a compound that has a crystal structure belonging to a space group FM3-M and that is represented by the composition formula (1): LixAyMezO?F???(1) wherein A denotes Na or K, Me denotes one or two or more elements selected from the group consisting of Mn, Co, Ni, Fe, Al, B, Ce, Si, Zr, Nb, Pr, Ti, W, Ge, Mo, Sn, Bi, Cu, Mg, Ca, Ba, Sr, Y, Zn, Ga, Er, La, Sm, Yb, V, and Cr, and the following conditions are satisfied. 1.7?x+y?2.2 0<y?0.2 0.8?z?1.3 1???2.5 0.

Abstract: A positive electrode active material includes a lithium composite oxide and a covering material that covers a surface of the lithium composite oxide. The covering material has an electron conductivity of 106 S/m or less. The lithium composite oxide is a multiphase mixture including a first phase having a first crystal structure that belongs to a space group Fm-3m and a second phase having a second crystal structure that belongs to a space group other than a space group Fm-3m. The ratio I(18°-20°)/I(43°-46°) of a first integrated intensity I(18°-20°) of a first maximum peak present at a first diffraction angle 2? of 18° or more and 20° or less to a second integrated intensity I(43°-46°) of a second maximum peak present at a second diffraction angle 2? of 43° or more and 46° or less in an XRD pattern of the lithium composite oxide satisfies 0.05?I(18°-20°)/I(43°-46°)?0.90.

Abstract: Provided is an active material for a fluoride-ion secondary battery, the active material containing a composite fluoride. The composite fluoride has a layered structure and is represented by a composition formula AmMnFx, where A is an alkali metal, M is a transition metal, 0<m?2, 1?n?2, and 3?x?4. The alkali metal may be at least one kind selected from the group consisting of Na, K, Rb, and Cs. The transition metal may be a 3d transition metal.