Abstract: A negative electrode for a lithium ion secondary battery includes a current collector and an active material-containing layer disposed on the current collector. The active material-containing layer includes: a first negative electrode active material including a carbon material; a second negative electrode active material including a metal element or a metalloid element as a constituent element, the metal element or the metalloid element being capable of forming an alloy with lithium; and a binder. The first negative electrode active material contains a spherical graphite, and the binder contains an acrylic resin.

Abstract: The secondary cell with the nonaqueous electrolyte includes: the wound body in which an electrode group including the positive electrode, the negative electrode, and a separator sandwiched therebetween is wound in a flat shape; and the nonaqueous electrolyte having the wound body immersed therein. The wound body, in the central section within at least five layers from the inside of the wound body, includes a gap between adjacent layers of the electrode group and a length Gn of the gap in a major axis direction of the wound body when viewed from the axial direction of the wound body fulfills a relationship of 0.09/n?0.003?Gn?0.98/n?0.093 (1?n?4).

Abstract: A negative electrode of a lithium ion secondary battery of the present invention includes a current collector (32) and a negative electrode active material layer (34) provided on the current collector (32). In the negative electrode of a lithium ion secondary battery, the negative electrode active material layer (34) includes carbon particles, a degree of graphitization of the carbon particles is 1.0 or more and 1.5 or less and a degree of orientation of the carbon particles is 50 or more and 150 or less; where, the degree of graphitization is a ratio (P101/P100) between a peak intensity P101 of the (101) plane and a peak intensity P100 of the (100) plane in an X-ray diffraction pattern and the degree of orientation is a ratio (P002/P110) between a peak intensity P002 of the (002) plane and a peak intensity P110 of the (110) plane in an X-ray diffraction pattern.

Abstract: A rare-earth magnet is an R-T-B-based rare-earth magnet containing a rare-earth element R, a transition metal element T, and boron B. The rare-earth magnet further contains Cu and Co, while having a Cu concentration distribution with a gradient along a direction from a surface of the rare-earth magnet to the inside thereof, Cu having a higher concentration on the surface side of the rare-earth magnet than on the inside thereof, and a Co concentration distribution with a gradient along a direction from the surface of the rare-earth magnet to the inside thereof, Co having a higher concentration on the surface side of the rare-earth magnet than on the inside thereof. The rare-earth magnet is excellent in corrosion resistance.

Abstract: A negative electrode for a lithium ion secondary battery includes a current collector and an active material-containing layer disposed on the current collector. The active material-containing layer includes: a first negative electrode active material including a carbon material; a second negative electrode active material including a metal element or a metalloid element as a constituent element, the metal element or the metalloid element being capable of forming an alloy with lithium; and a binder. The first negative electrode active material contains a spherical graphite, and the binder contains an acrylic resin.

Abstract: A negative electrode of a lithium ion secondary battery of the present invention includes a current collector (32) and a negative electrode active material layer (34) provided on the current collector (32). In the negative electrode of a lithium ion secondary battery, the negative electrode active material layer (34) includes carbon particles, a degree of graphitization of the carbon particles is 1.0 or more and 1.5 or less and a degree of orientation of the carbon particles is 50 or more and 150 or less; where, the degree of graphitization is a ratio (P101/P100) between a peak intensity P101 of the (101) plane and a peak intensity P100 of the (100) plane in an X-ray diffraction pattern and the degree of orientation is a ratio (P002/P110) between a peak intensity P002 of the (002) plane and a peak intensity P110 of the (110) plane in an X-ray diffraction pattern.

Abstract: A negative electrode active material includes a carbon material, and at least one sulfur component selected from the group consisting of sulfur atoms and a sulfur compound, wherein a content of the sulfur component with respect to a total amount of the carbon material and the sulfur component is 0.0005 mass % or more and 0.01 mass % or less in terms of S measured by a fluorescent X-ray analysis method, the carbon material is artificial graphite, and the artificial graphite has a bulk density of 0.2 g/cm3 or more and 2.5 g/cm3 or less. A negative electrode includes a negative electrode current collector, and a negative electrode active material layer formed on the negative electrode current collector, wherein the negative electrode active material layer includes the above-described negative electrode active material. A lithium ion secondary battery includes the above-described negative electrode, a positive electrode, and an electrolytic solution.

Abstract: A negative electrode active material for a lithium ion secondary battery includes a network structure formed by at least some of iron oxide particles being linked to each other.

Abstract: A negative electrode active material for a lithium ion secondary battery includes secondary particles formed by primary particles containing iron oxide that are linked in a chain.

Abstract: A negative electrode active material for a lithium ion secondary battery includes secondary particles formed by primary particles containing iron oxide that are linked in a chain.

Abstract: A negative electrode active material for a lithium ion secondary battery includes a network structure formed by at least some of iron oxide particles being linked to each other.

Abstract: The negative electrode for lithium-ion secondary battery is used in which a product of tensile strength and thickness of a negative electrode having a negative electrode active material layer containing silicon and silicon oxide as main components is 3.8 to 9.0 N/mm and a value obtained by dividing the product of the tensile strength and the thickness of the negative electrode by a product of tensile strength and thickness of a negative electrode current collector is 1.06 to 1.29.

Abstract: In the invention, a lithium-ion secondary battery, in which a value obtained by dividing average 3% modulus strength of a separator by average 3% modulus strength of a negative electrode including a negative electrode active material layer containing silicon and silicon oxide as a main component is 0.079 or less, is used.

Abstract: The negative electrode for lithium-ion secondary battery is used in which a product of tensile strength and thickness of a negative electrode having a negative electrode active material layer containing silicon and silicon oxide as main components is 3.8 to 9.0 N/mm and a value obtained by dividing the product of the tensile strength and the thickness of the negative electrode by a product of tensile strength and thickness of a negative electrode current collector is 1.06 to 1.29.

Abstract: In the invention, a lithium-ion secondary battery, in which a value obtained by dividing average 3% modulus strength of a separator by average 3% modulus strength of a negative electrode including a negative electrode active material layer containing silicon and silicon oxide as a main component is 0.079 or less, is used.

Abstract: A rare-earth magnet is an R-T-B-based rare-earth magnet containing a rare-earth element R, a transition metal element T, and boron B. The rare-earth magnet further contains Cu and Co, while having a Cu concentration distribution with a gradient along a direction from a surface of the rare-earth magnet to the inside thereof, Cu having a higher concentration on the surface side of the rare-earth magnet than on the inside thereof, and a Co concentration distribution with a gradient along a direction from the surface of the rare-earth magnet to the inside thereof, Co having a higher concentration on the surface side of the rare-earth magnet than on the inside thereof. The rare-earth magnet is excellent in corrosion resistance.