Abstract: A secondary battery disclosed herein includes a negative electrode including a negative electrode core body and a negative electrode active material layer formed on the negative electrode core body and including a negative electrode active material. The negative electrode active material layer has, in a Log differential pore volume distribution obtained by a mercury intrusion method, a first peak P1 and a second peak P2 with a larger pore diameter than the first peak P1 in a range where a pore diameter is 0.50 ?m or more and 6.00 ?m or less. The pore volume of pores corresponding to the first peak P1 is 6 mL/g or more.

Abstract: The positive electrodes each have a core-body exposed part at which a positive electrode core body is exposed, and a base part in which a composite material layer is formed on at least one surface of the positive electrode core body. The base part has formed therein a first region in which an active material is embedded in the positive electrode core body and a second region in which the the average embedment depth of active material embedded in the positive electrode core body is smaller than that in the first region. The second region is formed adjacent to the core-body exposed part.

Abstract: Provided is a positive electrode capable of increasing capacity and output of a nonaqueous electrolyte secondary battery. A positive electrode disclosed here includes a positive electrode current collector and a positive electrode active material layer supported by the positive electrode current collector. The positive electrode active material layer includes particles of a lithium composite oxide having a layered structure as a positive electrode active material. The positive electrode active material layer has a porosity of 17% to 20%. A peak pore size in pore distribution of the positive electrode active material layer measured by mercury intrusion porosimetry is 0.400 ?m to 0.550 ?m.

Abstract: Provided is a positive electrode active material capable of increasing capacity of a nonaqueous electrolyte secondary battery and providing the nonaqueous electrolyte secondary battery with high capacity degradation resistance in repetitive charging and discharging. The positive electrode active material disclosed here includes first lithium composite oxide particles having a layered structure and second lithium composite oxide particles having a layered structure. The first lithium composite oxide particles have an average particle size (D50) of 3.0 ?m to 6.0 ?m. The first lithium composite oxide particles have a dibutyl phthalate absorption value of 15 mL/100 g to 27 mL/100 g. The second lithium composite oxide particles have an average particle size (D50) of 10.0 ?m to 22.0 ?m. The second lithium composite oxide particles have a dibutyl phthalate absorption value of 14 mL/100 g to 22 mL/100 g.

Abstract: Provided is a positive electrode active material capable of increasing capacity and output of a nonaqueous electrolyte secondary battery. A positive electrode active material disclosed here includes particles of a lithium composite oxide having a layered structure. The positive electrode active material has a tap density of 2.8 g/cm3 to 3.0 g/cm3, and the positive electrode active material has a dibutyl phthalate absorption value of 14.5 mL/100 g to 18.5 mL/100 g.

Abstract: A positive electrode is used for a nonaqueous electrolyte secondary battery. The positive electrode includes a positive electrode substrate and a positive electrode active material layer. The positive electrode active material layer is disposed on a surface of the positive electrode substrate. The positive electrode active material layer includes a first layer and a second layer. The second layer is disposed between the positive electrode substrate and the first layer. The first layer includes a first positive electrode active material. The first positive electrode active material includes first aggregated particles. The second layer includes a second positive electrode active material. The second positive electrode active material includes second aggregated particles and single-particles. Each of the first aggregated particles and the second aggregated particles is formed by aggregation of 50 or more primary particles. The single-particles have an arithmetic mean diameter larger than the primary particles.

Abstract: A negative electrode active material is prepared by mixing a first graphite particle and a second graphite particle. A negative electrode including the negative electrode active material is produced. A non-aqueous electrolyte secondary battery including the negative electrode, a positive electrode, and an electrolyte solution is produced. The first graphite particle has a first number-based particle size distribution. The second graphite particle has a second number-based particle size distribution. A relationship of “D250/D150?0.50” is satisfied. D150 is a D50 in the first number-based particle size distribution. D250 is a D50 in the second number-based particle size distribution. A relationship of “R2?R1” is satisfied. R1 is an arithmetic mean of circularity of the first graphite particle. R2 is an arithmetic mean of circularity of the second graphite particle.

Abstract: A storage device includes a storage unit, and an evaluation value acquisition unit wherein the evaluation value acquisition unit is configured to acquire an evaluation value including at least a first evaluation value corresponding to the storage unit in a low-temperature region and a second evaluation value corresponding to the storage unit in a high-temperature region.

Abstract: A power storage device includes: power storage units each including at least one battery, the power storage units being connected in series; cell balance units connected in parallel to the respective power storage units via switches; and a control unit that performs control to charge the power storage units with a first constant current value, and, when the power storage unit having the highest voltage among the power storage units reaches a first potential, connect the corresponding one of the cell balance units to the power storage unit having the highest voltage, and switch the charging current to a second constant current value that is smaller than the first constant current value.

Abstract: A storage device includes a storage unit, and an evaluation value acquisition unit wherein the evaluation value acquisition unit is configured to acquire an evaluation value including at least a first evaluation value corresponding to the storage unit in a low-temperature region and a second evaluation value corresponding to the storage unit in a high-temperature region.

Abstract: A power storage device includes: power storage units each including at least one battery, the power storage units being connected in series; cell balance units connected in parallel to the respective power storage units via switches; and a control unit that performs control to charge the power storage units with a first constant current value, and, when the power storage unit having the highest voltage among the power storage units reaches a first potential, connect the corresponding one of the cell balance units to the power storage unit having the highest voltage, and switch the charging current to a second constant current value that is smaller than the first constant current value.

Abstract: A cathode contains: a lithium cobalt composite oxide expressed by LixCoaM1bM2cO2, where M1 denotes the first element; M2 indicates the second element; x, a, b, and c are set to values within ranges of 0.9?x?1.1, 0.9?a?1, 0.001?b?0.05, and 0.001?c?0.05; and a+b+c=1; a first sub-component element of at least one kind selected from a group containing Ti, Zr, and Hf, and a second sub-component element of at least one kind selected from a group containing Si, Ge, and Sn. 0.01 mol %?(content of the first sub-component element)?10 mol % as a ratio to cobalt in the lithium cobalt composite oxide. 0.01 mol %?(content of the second sub-component element)?10 mol % as a ratio to cobalt in the lithium cobalt composite oxide.

Abstract: A cathode contains: a lithium cobalt composite oxide expressed by LixCoaM1bM2cO2, where M1 denotes the first element; M2 indicates the second element; x, a, b, and c are set to values within ranges of 0.9?x?1.1, 0.9?a?1, 0.001?b?0.05, and 0.001?c?0.05; and a+b+c=1; a first sub-component element of at least one kind selected from a group containing Ti, Zr, and Hf, and a second sub-component element of at least one kind selected from a group containing Si, Ge, and Sn. 0.01 mol %?(content of the first sub-component element)?10 mol % as a ratio to cobalt in the lithium cobalt composite oxide. 0.01 mol %?(content of the second sub-component element)?10 mol % as a ratio to cobalt in the lithium cobalt composite oxide.