Abstract: A positive electrode active material includes a primary particle containing an olivine-type phosphate compound and a coating material containing carbon and coating at least part of a surface of the primary particle. In a TEM-EDS analysis, a Group 2 element is detected within the primary particle and within the coating material.

Abstract: A positive electrode active material includes a secondary particle, wherein: the secondary particle includes a first particle group and a second particle group; each of the first particle group and the second particle group is composed of primary particles; the second particle group has a larger average particle diameter than the first particle group; the first particle group and the second particle group are dispersed in each other in the secondary particle; the primary particles belonging to the first particle group contain a first olivine-type compound; the primary particles belonging to the second particle group contain a second olivine-type compound; and the second olivine-type compound has a lower Mn compositional ratio than the first olivine-type compound.

Abstract: A positive electrode active material includes a plurality of secondary particles, wherein each of the secondary particles includes a plurality of primary particles, each of the primary particles contains an olivine-type phosphate compound, carbon is attached to at least part of a surface of the primary particle, a cross-sectional surface of the secondary particle includes a first region and a second region, the first region includes a center of the secondary particle, the second region includes a surface of the secondary particle, a minimum circumscribed circle of the cross-sectional surface of the secondary particle has a radius of D, the first region is a circle including a center of the minimum circumscribed circle and having a radius of 0.5D, a relationship of 1.1?V1/V2 is satisfied, the V1 is a pore volume (cm3/g) in the first region, and the V2 is a pore volume (cm3/g) in the second region.

Abstract: A cathode active material includes a primary particle and a coating. The primary particle includes an olivine phosphate compound. The olivine phosphate compound includes at least one selected from the group consisting of lithium manganese phosphate and lithium manganese iron phosphate. The primary particle is doped with Me. The Me is a typical metal element serving as a divalent cation. The coating covers at least part of a surface of the primary particle. The coating contains carbon. At least one selected from the group consisting of an Me—C bond and an Me—O—C bond is detected by X-ray photoelectron spectroscopy.

Abstract: A positive electrode active material comprises a primary particle and a covering, wherein the primary particle includes an olivine-type phosphate compound, the covering covers at least part of a surface of the primary particle, and the covering includes carbon and phosphorus.

Abstract: A positive electrode active material comprises a primary particle and a covering, wherein the primary particle includes an olivine-type phosphate compound, the covering covers at least part of a surface of the primary particle, the covering includes carbon and Me, and Me is at least one type selected from the group consisting of a Group 4 metallic element, a Group 5 metallic element, a Group 6 metallic element, a Group 9 metallic element, a Group 10 metallic element, a Group 13 metallic element, and boron (B).

Abstract: The present disclosure relates to a cathode active material, a battery, and a method for producing a cathode active material. The cathode active material includes: an olivine phosphate compound including at least one selected from the group consisting of lithium manganese phosphate and lithium manganese iron phosphate; and a coating that covers at least part of a surface of the cathode active material, and contains carbon and iron.

Abstract: A positive electrode active material comprising a plurality of secondary particles, wherein: each of the secondary particles includes a plurality of primary particles; each of the primary particles contains an olivine-type phosphate compound; carbon is attached to at least part of a surface of the primary particle; a cross-sectional surface of the secondary particle includes a central portion and a peripheral portion; and a relationship of 0.5?Ii/Io is satisfied where Ii is an average value of signal intensities of carbon in the central portion in TEM-EDS line analysis along a diametrical direction of the secondary particle, and Io is an average value of signal intensities of carbon in the peripheral portion in TEM-EDS line analysis along the diametrical direction of the secondary particle.

Abstract: A positive electrode active material comprises secondary particles, wherein each of the secondary particles includes primary particles, each of the primary particles includes an olivine-type phosphate compound, and in a scanning electron microscope image of the secondary particle, a proportion of the primary particles each having a touching angle of 90° or less to the primary particles each having a maximum Feret diameter of 100 nm or more is 40% or more.

Abstract: A positive electrode active material includes secondary particles. Each of the secondary particles includes primary particles. Each of the primary particles includes an olivine-type phosphate compound. An open pore is formed in the secondary particle. The open pore is a non-through hole. A cross section of the secondary particle satisfies relationships of “0.9?d/D?10.1” and “1.9?Sd/d?33.4”. “d” represents a maximum depth of the open pore. “D” represents an opening diameter of the open pore. “Sd” represents a diameter of a smallest circumcircle of the cross section of the secondary particle.

Abstract: A positive electrode active material includes secondary particles. Each of the secondary particles includes primary particles. Each of the primary particles includes an olivine-type phosphate compound. A part of a surface of the secondary particle has a depression. At the depression, the surface of the secondary particle is depressed in a shape of a concave surface. A cross section of the secondary particle satisfies a relationship of “0.41?Sa/Ca?0.95”. “Sa” represents an area of the cross section of the secondary particle. “Ca” represents an area of a smallest circumcircle of the cross section of the secondary particle.

Abstract: A positive electrode active material comprises secondary particles, wherein each of the secondary particles includes primary particles, and each of the primary particles includes an olivine-type phosphate compound and lithium zirconate.

Abstract: A positive electrode active material comprising secondary particles, wherein each of the secondary particles includes primary particles, each of the primary particles includes an olivine-type phosphate compound, the olivine-type phosphate compound includes lithium manganese iron phosphate, a pore volume of the positive electrode active material is from 0.05 cm3/g to 0.18 cm3/g, a crystallite size of the positive electrode active material is from 10 nm to 90 nm, an average particle size of the primary particles is from 20 nm to 90 nm, a molar fraction of a content of manganese relative to contents of manganese and iron in the lithium manganese iron phosphate is from 0.4 to 0.9, and a proportion of the secondary particles each having an open pore to the secondary particles each having a maximum Feret diameter greater than 10 ?m is more than 65%.

Abstract: An electrode comprising a current-collecting foil sheet and a positive electrode layer, wherein the positive electrode layer is placed on a surface of the current-collecting foil sheet, the positive electrode layer includes a positive electrode active material, the positive electrode active material includes secondary particles, each of the secondary particles includes primary particles, the secondary particles include pored particles each having a pore, a cross section of the positive electrode layer includes a first region and a second region, the first region and the second region are defined as two equal parts formed by dividing the cross section of the positive electrode layer into half in a thickness direction, the first region is interposed between the current-collecting foil sheet and the second region, and a relationship of 50%?X is satisfied.

Abstract: A positive electrode active material includes tertiary particles. Each of the tertiary particles includes secondary particles. Each of the secondary particles includes primary particles. Each of the primary particles includes lithium manganese iron phosphate.

Abstract: A positive electrode active material comprises tertiary particles. Each of the tertiary particles includes secondary particles. Each of the secondary particles includes primary particles. Each of the primary particles includes an olivine-type phosphate compound. In at least part of the tertiary particle, a vacant space is formed between the secondary particles.

Abstract: The present disclosure provides a positive electrode active material layer which can improve battery capacity, a lithium-ion battery comprising such a positive electrode active material layer, and a method for manufacturing such a positive electrode active material layer. The positive electrode active material layer 20 of the present disclosure comprises a positive electrode active material 21a and a lithium alloy 22a of lithium and a metal element. The positive electrode active material is coated with a carbon material, the metal element has an alloying potential with lithium of 0.5V (vs. Li/Li+) or more, and the lithium alloy is arranged on a surface of closer to the positive electrode current collector and/or separator of the positive electrode active material layer. A lithium-ion battery of the present disclosure comprises a positive electrode active material layer of the present disclosure, which is interposed between a positive electrode current collector and a separator.

Abstract: The method of the present disclosure for producing a lithium-ion battery includes providing a positive electrode precursor layer containing at least lithium alloy particles and a positive electrode active material, obtaining a lithium-ion battery precursor having the positive electrode precursor layer, the separator layer, and the negative electrode active material layer in an order of the positive electrode precursor layer, the separator layer, and the negative electrode active material layer and impregnated with an electrolyte solution, and performing initial charging on the lithium-ion battery precursor to make the positive electrode precursor layer a positive electrode active material layer, wherein the lithium alloy particle is a lithium alloy particle with a lithium-alloying potential of 0.5 V (vsLi/Li+) or higher, and with a particle diameter D90 smaller than 70 ?m as measured by a laser diffraction and scattering method.

Abstract: A method for manufacturing a lithium-ion battery according to the present disclosure includes: providing a positive electrode precursor layer containing at least a lithium (Li) alloy with a Li alloying potential of 0.5 V (vsLi/Li+) or higher and a positive electrode active material; obtaining a lithium-ion battery precursor including the positive electrode precursor layer, a separator layer, and a negative electrode active material layer in this order and impregnated with an electrolyte solution; and performing initial charging of the lithium-ion battery precursor to change the positive electrode precursor layer to a positive electrode active material layer.

Abstract: Provided is a negative electrode active material that contains silicon clathrate II and that is suitable for a negative electrode of a lithium ion secondary battery. The negative electrode active material includes a silicon material in which silicon clathrate II represented by composition formula NaxSi136 (0?x?10) is contained and a volume of a pore having a diameter of not greater than 100 nm is not less than 0.025 cm3/g.