Abstract: An energy storage device includes a positive electrode and a negative electrode. The negative electrode includes graphite and non-graphitizable carbon, and a D50 particle size of the graphite at which a cumulative volume in a particle size distribution of a particle size reaches 50% is 2 ?m or more. A ratio of a mass of the non-graphitizable carbon to a total amount of a mass of the graphite and a mass of the non-graphitizable carbon is 5% by mass or more and 45% by mass or less and a ratio of the D50 particle size of the graphite to a D50 particle size of the non-graphitizable carbon is 1.02 or less.

Abstract: An energy storage unit having plural energy storage devices, each of which includes a container housing an electrode assembly and positive and negative electrode terminals electrically connected to the electrode assembly and extending from the container in the same direction, includes: a bus bar electrically connecting a first terminal, which is one of the positive electrode terminal and the negative electrode terminal of a first energy storage device included in the plural energy storage devices, and a second terminal, which is one of the positive electrode terminal and the negative electrode terminal of a second energy storage device included in the plural energy storage devices and opposite in polarity to the first terminal; a packing member interposed between the first terminal and the container of the first energy storage device; and an insulating member interposed between the bus bar and the container of the first energy storage device.

Abstract: An energy storage device includes a positive electrode, a negative electrode, and a nonaqueous electrolyte solution. The negative electrode includes an active material layer, and the active material layer has pores having a pore size of 0.1 ?m or more and 1.0 ?m or less, and a total volume of the pores is 0.26 cm3/g or more and 0.46 cm3/g or less.

Abstract: An energy storage device includes a positive electrode, a negative electrode, and an insulating layer arranged between these electrodes to electrically insulate these electrodes. The negative electrode includes a composite layer containing active material particles. The composite layer of the negative electrode, and the positive electrode are arranged to face each other across the insulating layer. The insulating layer contains electrically insulating particles, and is made porous by a gap between these particles. The composite layer of the negative electrode is made porous by a gap between the active material particles, and “?0.8?Log B?Log A?1.0” is satisfied in which in a pore distribution of the composite layer, a pore peak diameter is represented by A (?m), and in a pore distribution of the insulating layer, a peak diameter is represented by B (?m).

Abstract: A secondary battery includes an opening portion provided to a case. A first sealing body is provided to the opening portion, the first sealing body being displaced or deformed by a pressure difference between an inside and an outside of the case in such manners that the first sealing body is pressed by internal pressure to allow outflow of inside air from the opening portion when the internal pressure in the case is higher than external pressure and that the first sealing body is pressed by the external pressure to prevent entry of outside air from the opening portion when the internal pressure in the case is lower than the external pressure. Pressure in a space surrounded with the case and the first sealing body is set to be lower than pressure outside the space.

Abstract: Provided is an energy storage device including an electrolyte solution including a compound represented by the general formula (1), a compound represented by the general formula (2), and a compound represented by the general formula (3):

Abstract: An energy storage device including a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte, wherein the negative electrode includes a negative electrode active material layer containing a non-graphitizable carbon as a negative electrode active material, and the negative electrode active material has a negative electrode active material weight per unit volume of the negative electrode active material layer of 0.92 g/cc or more and 1.13 g/cc or less and a particle size D90 of 4.3 ?m or more and 11.5 ?m or less, the particle size D90 being a particle size in particle size distribution in which a cumulative volume is 90%.

Abstract: An energy storage device comprises a positive electrode, a negative electrode, a separator arranged between the positive electrode and the negative electrode, and a nonaqueous electrolyte. The negative electrode has a negative substrate layer, and a negative composite layer arranged on the surface of the negative substrate layer. The separator has a separator substrate layer. The negative composite layer contains a non-graphitizable carbon having a particle diameter D50 of 2.0 ?m or more and 6.0 ?m or less. A corrected negative electrode density, which is defined as a value obtained by dividing, by a thickness of the separator substrate layer, a value obtained by multiplying a density of the negative composite layer by a thickness of the negative composite layer, is 1.2 (g/cm3) or more and 5.1 (g/cm3) or less.

Abstract: An electric storage device is provided with an electrode assembly including a positive electrode plate and a negative electrode plate; a case for housing the electrode assembly; a positive-electrode external terminal arranged on an outer surface of the case and electrically connected to the positive electrode plate; a negative-electrode external terminal arranged on an outer surface of the case and electrically connected to the negative electrode plate; and a gas exhaust valve formed in a region of the case on the opposite side of a region where the positive-electrode external terminal and the negative-electrode external terminal are arranged.

Abstract: An energy storage device includes a positive electrode and a negative electrode. The negative electrode includes graphite and non-graphitizable carbon, and a D50 particle size of the graphite at which a cumulative volume in a particle size distribution of a particle size reaches 50% is 2 ?m or more. A ratio of a mass of the non-graphitizable carbon to a total amount of a mass of the graphite and a mass of the non-graphitizable carbon is 5% by mass or more and 45% by mass or less and a ratio of the D50 particle size of the graphite to a D50 particle size of the non-graphitizable carbon is 1.02 or less.

Abstract: Provided is an electric storage device including a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, a nonaqueous electrolyte solution in which an electrolyte is dissolved in a nonaqueous solvent, wherein an inorganic filler layer is disposed between the positive electrode and the negative electrode and the nonaqueous electrolyte solution contains lithium difluorobis(oxalato)phosphate.

Abstract: In an energy storage device including a positive electrode plate and a negative electrode plate that are insulated from each other with a separator interposed therebetween, and a non-aqueous electrolyte, the separator includes a base material layer and a coating layer that is disposed on at least one surface of the base material layer, and the separator has an air permeability of the base material layer of 25 (sec/100 cc) or greater and 250 (sec/100 cc) or less, a porosity of the base material layer of 45% or greater, an air permeability of an interface between the base material layer and the coating layer of 15 (sec/100 cc) or less, and an air permeability of the coating layer of 15 (sec/100 cc) or less.

Abstract: An electric storage device having a positive electrode, a negative electrode, a separator located between the positive electrode and the negative electrode, and a nonaqueous electrolyte. The positive electrode has a positive substrate layer, a positive composite layer containing a positive active material, and an undercoat layer located between the positive substrate layer and the positive composite layer. A density of the positive composite layer is 2.1 g/cm3 or more and 2.7 g/cm3 or less. The positive electrode has the rate of increase in sheet resistance after a solvent immersion test of 30% or less. The undercoat layer contains a binder selected from the group consisting of chitosan derivatives, cellulose derivatives and acrylic acid derivatives.

Abstract: An energy storage device includes: an electrode assembly which includes: an approximately rectangular positive electrode; an approximately rectangular negative electrode which is stacked alternately with the positive electrode; and a strip-like elongated separator having a base material layer and an inorganic layer which is made to overlap with the first base material layer, wherein the elongated separator is arranged between the positive electrode and the negative electrode, and the base material layer of the elongated separator faces the negative electrode in an opposed manner between the positive electrode and the negative electrode.

Abstract: An energy storage device includes a positive electrode, a negative electrode, and a nonaqueous electrolyte solution. The negative electrode includes an active material layer, and the active material layer has pores having a pore size of 0.1 ?m or more and 1.0 ?m or less, and a total volume of the pores is 0.26 cm3/g or more and 0.46 cm3/g or less.

Abstract: An energy storage device includes a positive electrode, a negative electrode, and an insulating layer arranged between these electrodes to electrically insulate these electrodes. The negative electrode includes a composite layer containing active material particles. The composite layer of the negative electrode, and the positive electrode are arranged to face each other across the insulating layer. The insulating layer contains electrically insulating particles, and is made porous by a gap between these particles. The composite layer of the negative electrode is made porous by a gap between the active material particles, and “?0.8?Log B?Log A?1.0” is satisfied in which in a pore distribution of the composite layer, a pore peak diameter is represented by A (?m), and in a pore distribution of the insulating layer, a peak diameter is represented by B (?m).

Abstract: An electric storage device includes: an electrode assembly in which electrodes are wound such that paired curved portions and a straight portion connecting the paired curved portions are formed; a case which houses the electrode assembly, the case comprising a convex part protruding toward the straight portion of the electrode assembly to support the straight portion; and a support portion which supports the curved portion toward an inside of the electrode assembly.

Abstract: An energy storage device includes a positive electrode provided with a positive composite layer containing a positive active material, a negative electrode provided with a negative composite layer containing a negative active material, and a separator partitioning between the positive electrode and the negative electrode, wherein the separator includes a substrate uniaxially drawn into a sheet shape and a coating layer coating at least one of surfaces of the substrate, and the coating layer has an anisotropic structure with orientation in a direction different from a drawing direction of the substrate.

Abstract: Provided is an energy storage device including an electrolyte solution including a compound represented by the general formula (1), a compound represented by the general formula (2), and a compound represented by the general formula (3):

Abstract: An energy storage device comprising: a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, a nonaqueous electrolyte, and an insulating layer disposed between the positive electrode and the separator, wherein the positive electrode contains a compound represented by LiaNibCocMdWxNbyZrzO2 (provided that a, b, c, d, x, y and z satisfy the equations of 0?a?1.2, 0?b?1, 0.1?c?0.4, 0?d?0.5, 0?x?0.1, 0?y?0.1, 0?z?0.1 and b+c+d=1, and M denotes at least one kind of element selected from the group consisting of Mn, Ti, Cr, Fe, Co, Cu, Zn, Al, Ge, Sn and Mg) as a positive active material and the negative electrode contains hardly graphitizable carbon with a D50 particle diameter greater than or equal to 1.0 ?m and less than or equal to 6.0 ?m as a negative active material.