Abstract: A non-aqueous electrolyte secondary battery includes: a pressure-type current interrupt device arranged in a conductive path, for interrupting the conductive path when an internal pressure exceeds a working pressure; a non-aqueous electrolyte; and a positive electrode composite material layer. The non-aqueous electrolyte contains a gas generation agent that generates a gas in an overcharge region, and the positive electrode composite material layer contains a first positive electrode active material particle including lithium iron phosphate, and a second positive electrode active material particle including lithium-nickel composite oxide. A ratio of the first positive electrode active material particle to a total mass of the first positive electrode active material particle and the second positive electrode active material particle is 5% by mass or more and 20% by mass or less.

Abstract: A method of manufacturing a secondary battery is provided. According to the manufacturing method, laser light includes first peak light applied to a first irradiation position located on a cover body, second peak light applied to a second irradiation position located between the first irradiation position and a connecting surface, and third peak light applied to the connecting surface. The first peak light is higher in intensity than the second peak light and the third peak light. The third peak light is higher in intensity than the second peak light.

Abstract: A flat-plate portion of a negative electrode composite material layer includes a first end portion at one end portion in a direction of axis of winding of a flat electrode winding assembly, a second end portion located opposite to the first end portion, and a central portion lying between the first end portion and the second end portion. The flat-plate portion of the negative electrode composite material layer is provided with a plurality of communication grooves. The communication groove includes a first terminal end portion at the first end portion, includes a second terminal end portion at the second end portion, includes in the central portion, a starting portion located closer to a bottom portion of a prismatic case relative to the first terminal end portion and the second terminal end portion, and extends from the starting portion toward the first terminal end portion and the second terminal end portion.

Abstract: Provided is a separator for a battery in which, when a ratio of a total length of line segments (Sa), in which an arbitrary straight line (La) intersects with resin fibers (4), to a total length of the straight line (La) on a cross-section of the separator in a thickness direction (TD) is represented by s (%) and when a thickness of the separator is represented by d (?m), 0<s?100, 3?d?50, and 300?d×s?1500 are satisfied, the straight line (La) being parallel to a first main surface (40a) and crossing the cross-section.

Abstract: A nonaqueous electrolyte secondary battery includes a wound electrode assembly in which a positive electrode having, at its one end in a width direction, a positive electrode exposed portion provided without a positive electrode mixture layer on a positive electrode current collector and a negative electrode are wound together, with a separator interposed therebetween. The positive electrode exposed portion protrudes outward in an axial direction of the wound electrode assembly relative to the separator and the negative electrode at one end in the axial direction of the wound electrode assembly. The negative electrode exposed portion protrudes outward in the axial direction of the wound electrode assembly relative to the separator and the positive electrode at the other end in the axial direction. The positive electrode exposed portion has a cutout portion at least in an outermost circumferential portion of the positive electrode.

Abstract: A lithium ion secondary battery, improved in durability against high-rate charging/discharging, which includes, in the negative electrode active material layer, a negative electrode active material formed of a graphite carbon material having a graphite structure in at least a part thereof, and a conductive carbon material, which is different from the graphite carbon material and is formed of a conductive amorphous carbon. The negative electrode active material has a bulk density of 0.5 g/cm3 or more and 0.7 g/cm3 or less, and a BET specific surface area of 2 m2/g or more and 6 m2/g or less. The conductive carbon material has a bulk density of 0.4 g/cm3 or less, and a BET specific surface area of 50 m2/g or less.

Abstract: A nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a separator. The positive electrode includes a positive electrode current collector, a first positive electrode mixture layer that is provided on the positive electrode current collector, and a second positive electrode mixture layer that is provided on the first positive electrode mixture layer. The first positive electrode mixture layer includes a first positive electrode active material and a first conductive material. The second positive electrode mixture layer includes a second positive electrode active material and a second conductive material. The first positive electrode active material includes a lithium composite oxide having a layered crystal structure. The second positive electrode active material includes a lithium composite phosphate having an olivine-type crystal structure.

Abstract: A method of manufacturing a nonaqueous electrolyte secondary battery includes: a step of forming a first electrode mixture layer containing an electrode active material and a first binder; a step of forming granulated particles containing the electrode active material and a second binder; a step of forming a second electrode mixture layer, which is formed of the granulated particles, on the first electrode mixture layer; a step of forming a heat resistance layer, which contains an inorganic filler and a third binder, on a surface of a separator; a step of preparing an electrode body by laminating the electrode and the separator such that the second electrode mixture layer and the heat resistance layer are in contact with each other; and a step of heating the electrode body.

Abstract: A secondary cell manufacturing method includes placing a current collector terminal on a plurality of laminated current collector foils from a lamination direction of the current collector foils. The current collector terminal has a first end portion, and a second end portion forming a cutout with the first end portion. The second end portion includes a base part, and a thin-walled part having a smaller thickness than the base part. The secondary cell manufacturing method includes welding the plurality of current collector foils to the current collector terminal by scanning the plurality of current collector foils disposed in the cutout with a laser beam along the first extension direction toward the second end portion while irradiating the plurality of current collector foils with the laser beam.

Abstract: An electrode for a nonaqueous electrolyte secondary battery includes an electrode mixture layer. The electrode mixture layer contains a hollow active material particle and a needle-shaped filler having a through-hole that extends through the needle-shaped filler in a longitudinal direction. The needle-shaped filler is arranged on surfaces of the hollow active material particle.

Abstract: A method of manufacturing a sealed battery includes a welding step of forming a welded portion, and the welding step includes a first step of sequentially forming a plurality of weld beads in an opening edge portion and an outer peripheral edge portion such that the plurality of weld beads are spaced apart from one another, and a second step of forming a weld bead in each gap portion located between the weld beads, with a plurality of gap portions being formed in the opening edge portion and the outer peripheral edge portion.

Abstract: An electrical storage device includes a polar plate and a collector plate. The polar plate includes a mixture layer and a collector. The collector includes an exposed portion. The exposed portion is exposed from the mixture layer in one end of the polar plate in a width direction. The collector plate includes a facing portion, a projection portion, and a corner portion. The facing portion is opposed to a tip end surface of the exposed portion. The projection portion extends from the facing portion so as to project toward the exposed portion relative to the facing portion. The corner portion is placed in a boundary between the facing portion and the projection portion. The collector plate is welded to the exposed portion in at least part of the corner portion.

Abstract: A manufacturing method for a non-aqueous electrolyte secondary battery includes: forming a powder; forming a sheet-like green compact; and forming a heat-resistant layer. The powder contains composite particles and a solvent. The composite particles contain inorganic filler particles and a binder. The green compact is formed by pressing the powder in a state in which the solvent remains. The heat-resistant layer is formed by disposing the green compact on a surface of at least any of a positive electrode mixture layer and a negative electrode mixture layer after the green compact is formed.

Abstract: A nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, a separator provided between the positive electrode and the negative electrode, and a nonaqueous electrolytic solution at least held by the separator. The positive electrode has a positive electrode collector and a positive electrode mixture layer provided on the positive electrode collector. The positive electrode mixture layer has a first powder and a second powder. The first powder includes a first positive electrode active material, a first conductive material, and an organic-based binder. The second powder includes a second positive electrode active material, a second conductive material, and a water-based binder.

Abstract: A non-aqueous electrolyte secondary battery includes a positive electrode composite material layer, the positive electrode composite material layer including: a composite particle including a positive electrode active material, a first conductive material and a binder; and a second conductive material arranged on a surface of the composite particle and having a DBP oil absorption number smaller than that of the first conductive material.

Abstract: A secondary battery includes a scaling body (25), a rivet member (30), a gasket (27) that contacts the rivet member (30) and is fixed between the sealing body (25) and the rivet member (30), a holder member (60), a reversing plate (40) that deforms when an internal pressure of the exterior body (10) rises, and a heat accumulation portion (70) that contacts the rivet member (30) and has a higher thermal conductivity than the rivet member (30). An outer peripheral edge (42) of the reversing plate (40) is connected by welding to the peripheral edge portion (36) of the rivet member (30), and the heat accumulation portion (70) is sandwiched between the opposing portion (33) of the rivet member (30) and the extending portion (61) of the holder member (60).

Abstract: This invention provides a sealed secondary battery comprising a current cutoff mechanism. The current cutoff mechanism has a current breaking valve 30 comprising a sloped side wall 32A which tapers with decreasing diameter from the inner circumference of a flange 32 and a dome 32B descending in a spherical cap shape from the rim of sloped side wall 32A. The rotation axis L of sloped side wall 32A and the sloped side wall 32A form an angle ? to satisfy 60°???75° while dome 32B has a sphere radius R of 30 mm or larger, but smaller than 100 mm. In a planer view along the rotation axis L, the outer circumference of dome 32B is located outside the outer circumference of a thin portion 76.

Abstract: A secondary battery includes: a battery element; a case housing the battery element; a positive-electrode external terminal and a negative-electrode external terminal provided outside the case and electrically connected to the battery element; and a short-circuiting mechanism configured to establish a short-circuit between the positive and negative external terminals through the case. The short-circuiting mechanism includes a conducting portion conductively connected to one of the positive and negative external terminals so as to face the case, an inversion plate provided at a portion of the case facing the conducting portion and configured to deform to approach the conducting portion when an internal pressure of the case rises, and a brazing material provided on one of the conducting portion and the inversion plate at a position between the conducting portion and the inversion plate.

Abstract: A method for manufacturing an electrode sheet includes the steps of forming a granulated material containing a plurality of granules; forming an electrode mixture layer by molding the granulated material into a sheet; and placing the electrode mixture layer on electrode current collector foil. The step of forming the granulated material includes the steps of forming a granule containing at least an electrode active material and a binder; and adhering a polyglycerol fatty acid ester to a surface of the granule.

Abstract: A nonaqueous electrolyte secondary battery includes: a negative electrode current collector core; and a negative electrode mixture layer that is formed on the negative electrode current collector core. The negative electrode mixture layer contains a diene rubber binder. A section of the negative electrode mixture layer in a thickness direction is divided into a first region, a second region, and a third region from a negative electrode current collector core side by trisecting the negative electrode mixture layer in the thickness direction. An abundance of the diene rubber binder in the second region is greater than an abundance of the diene rubber binder in the first region. The third region contains the diene rubber binder having an oxidized carbon-carbon double bond.