Gs Yuasa International Ltd.

Tomonori Kako

Takeshi Sasaki

Sumio Mori

Akihiko Miyazaki

Kenta Nakai

Shota Ito

Katsushi Nishie

Kazuki Kawaguchi

Masashi Takano

Yudai Kawasoe

Shinya Kitano

Hidefumi Hasegawa

Ryosuke Shimokawa

Ukyo Harinaga

Taro Yamafuku

Jun Oyama

Takeshi Saski

Taisei Sekiguchi

Kenta Uehira

An aspect of the present invention is a nonaqueous electrolyte energy storage device including: a positive electrode having a positive composite layer including a positive active material; a negative electrode having a negative composite layer including a negative active material; and a nonaqueous electrolyte including a nonaqueous solvent, in which the positive active material includes a lithium-transition metal composite oxide that contains nickel as a transition metal and has a layered α-NaFeO-type crystal structure, a ratio (N/P) between mass (N) per unit area of the negative active material and mass (P) per unit area of the positive active material is 0.30 or more and 0.45 or less, the nonaqueous solvent contains PC, DEC, and EMC, a content of the PC in the nonaqueous solvent is 25% by volume or more and 55% by volume or less, a total content of the DEC and the EMC in the nonaqueous solvent is 45% by volume or more and 75% by volume or less, and a content of the DEC is equal to or higher than the content of the EMC.

Nonaqueous electrolyte energy storage device and energy storage apparatus

One aspect of the present invention is an energy storage device including a positive electrode containing: first positive active material particles containing a metal element capable of forming a conductive metal oxide; and second positive active material particles not containing the metal element, in which the first positive active material particles include a nickel-cobalt-manganese-containing lithium-transition metal composite oxide containing lithium, nickel, cobalt, and manganese as constituent elements, and the first positive active material particles are larger in median diameter than the second positive active material particles.

Energy storage device

The present embodiment provides a lithium ion secondary battery including a positive electrode containing LiNiCoMO(0.9&#x2264;a&#x2264;1.2, 0.3&#x2264;x&#x2264;0.8, 0.2&#x2264;y+z&#x2264;0.7, where M is a metal element other than Li, Ni, and Co) as a positive active material, and a negative electrode containing non-graphitic carbon as a negative active material. In this lithium ion secondary battery, at a portion where the positive electrode and the negative electrode face each other, a basis weight (P) of the positive active material and a basis weight (N) of the negative active material satisfy a relational expression of 0.65&#x2264;P/N&#x2264;1.05.

Lithium ion secondary battery

An energy storage device includes a negative electrode having a negative active material layer containing amorphous carbon as an active material, a curve attained by determining a rate of change (dQ/dV) in a potential (V) of the amorphous carbon in a discharge capacity (Q) of the amorphous carbon per unit quantity based on a result attained by measuring the potential (V) with respect to the discharge capacity (Q) and representing the rate of change (dQ/dV) with respect to the potential (V) has one or more peaks in a range in which the potential of the amorphous carbon is 0.8 V or more and 1.5 V or less, and a potential of the negative electrode at time of full charge is 0.25 V or more with respect to a lithium potential.

Energy storage device and energy storage apparatus

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.

Energy storage device and method of producing energy storage device

An energy storage device includes: a positive electrode plate containing a positive composite layer including a positive active material capable of occluding and releasing a lithium ion; and a negative electrode plate containing a negative composite layer including a negative active material capable of occluding and releasing a lithium ion. A peak pore diameter Rp of the positive composite layer in a pore distribution measured by a mercury penetration method is 0.5 &#x3bc;m or less, and a peak pore diameter Rn of the negative composite layer in a pore distribution measured by a mercury penetration method is 0.5 &#x3bc;m or less. A ratio Rp/Rn of the peak pore diameter of the positive composite layer to the peak pore diameter of the negative composite layer is 0.60 or more and 1.70 or less.

An energy storage device is provided that has improved power performance at low temperature. In the present embodiment, an energy storage device is provided that includes an electrode having an active material layer, the active material layer contains at least active material particles, the particles contained in the active material layer gives a volume-based particle size frequency distribution that has a first peak and a second peak appearing in a particle size larger than a particle size of the first peak, and particles having particle sizes equal to or smaller than a particle size Dx have a volume proportion of 49% or more and 62% or less in a volume of whole particles contained in the active material layer, with the particle size Dx defined as a particle size at a local minimum frequency between the first peak and the second peak in the particle size frequency distribution.

Energy storage device and method for manufacturing energy storage device

An energy storage device includes a positive electrode having a positive active material layer containing an active material in the form of particles. The positive active material layer contains primary particles of the active material and secondary particles formed by aggregation of a plurality of primary particles. The proportion of primary particles relative to all particles of the active material in the positive active material layer is 5% or more and 40% or less. An method for producing an energy storage device includes preparing a positive electrode having a positive active material layer by forming a positive active material layer from a composite containing at least secondary particles of an active material, and assembling an energy storage device using the prepared positive electrode. In the preparation of the positive electrode, the positive active material layer is pressed to deagglomerate some of the secondary particles into primary particles, and the proportion of primary particles relative to all particles of the active material in the positive active material layer is adjusted to 5% or more and 40% or less.

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.

An energy storage device having sufficient energy density and sufficient power is provided. In this embodiment, an energy storage device that includes a negative electrode containing an active material layer including an active material is provided. The active material layer includes particulate graphite as the active material. A particle diameter frequency distribution of the graphite includes a first peak and a second peak which appears in a region where a particle diameter is larger than a particle diameter of the first peak, the particle diameter of the first peak is equal to or less than 10 &#x3bc;m and the particle diameter of the second peak is more than 10 &#x3bc;m. The active material layer further includes a particulate high hardness active material which has higher hardness than the graphite.

An energy storage device includes: a core; and a wound body including, layered and wound around the core: a positive electrode, a negative electrode, and two separators, one of which is interposed between the positive electrode and the negative electrode and each having a first surface and a second surface. The first surface has thermal bonding properties superior to thermal bonding properties of the second surface, and at least one of the two separators is bonded to the core via the first surface thereof.

Energy storage device, winding apparatus, and winding method

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 &#x3bc;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.

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.

Energy storage unit

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 '&#x2212;0.8&#x2266;Log B&#x2212;Log A&#x2266;1.0' is satisfied in which in a pore distribution of the composite layer, a pore peak diameter is represented by A (&#x3bc;m), and in a pore distribution of the insulating layer, a peak diameter is represented by B (&#x3bc;m).

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 &#x3bc;m or more and 1.0 &#x3bc;m or less, and a total volume of the pores is 0.26 cm/g or more and 0.46 cm/g or less.

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Kyoto, Japan

Tomonori Kako