Toyota Jidosha Kabushiki Kaisha

Panasonic Holdings Corporation

Yuji Yokoyama

Yusuke Fukumoto

Tatsuya Hashimoto

Hiroya Umeyama

Keisuke Ohara

Naoyuki Wada

Naoto Onodera

Nobuhiro Hirano

Masanori Sugimori

Yo Kato

Kazuhisa Takeda

Hideki Sano

Koji Torita

Keiichi Takahashi

Akihiro Taniguchi

Koichi Toriyama

Shuji Tsutsumi

Yutaka Oyama

Masahiro Morita

Toshihiko Mitsuhashi

A negative electrode for a nonaqueous electrolyte secondary battery comprises a negative electrode core body, and a negative electrode mixture layer. When the range of 40% of the thickness of the negative electrode mixture layer from the surface of the negative electrode mixture layer on the side opposite to the negative electrode core body is defined as a first region and the range of 40% of the thickness of the negative electrode mixture layer from the interface between the negative electrode mixture layer and the negative electrode core body is defined as a second region, the BET specific surface area of the graphite included in the first region is smaller than the BET specific surface area of the graphite included in the second region.

Negative electrode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery

A negative electrode for a nonaqueous electrolyte secondary battery, which is an example of embodiments, comprises a negative electrode core body and a negative electrode mixture layer provided on the surface of the negative electrode core body. The negative electrode mixture layer includes graphite and fibrous carbon. The BET specific surface area of the graphite included in the first region is smaller than the BET specific surface area of the graphite included in the second region. In addition, the average length of the fibrous carbon included in the first region is longer than the average length of the fibrous carbon included in the second region.

A negative electrode for a nonaqueous electrolyte secondary battery, which is an example of embodiments, comprises a negative electrode core body and a negative electrode mixture layer provided on the surface of the negative electrode core body. The negative electrode mixture layer includes graphite and fibrous carbon. The BET specific surface area of the graphite included in the first region is smaller than the BET specific surface area of the graphite included in the second region. In addition, the average length of the fibrous carbon included in the second region is longer than the average length of the fibrous carbon included in the first region.

A negative electrode for a nonaqueous electrolyte secondary battery comprises a negative electrode core body and a negative electrode mixture layer provided. When the range of 40% of the thickness of the negative electrode mixture layer from the surface of the negative electrode mixture layer is defined as a first region and the range of 40% of the thickness of the negative electrode mixture layer from the surface of the negative electrode core body is defined as a second region, the BET specific surface area of the graphite included in the first region is smaller than that of the graphite included in the second region. The first region includes the multiwalled fibrous carbon more than the single wall fibrous carbon in terms of mass and the second region includes the single wall fibrous carbon more than the multiwalled fibrous carbon in terms of mass.

A non-aqueous electrolyte secondary battery includes an electrode current collector, an intermediate layer, and an electrode active material layer. The intermediate layer is interposed between the electrode current collector and the electrode active material layer. The intermediate layer contains a metal-covered microcapsule. The metal-covered microcapsule includes a microcapsule and a metal film. The microcapsule includes a core and a shell. The shell surrounds the core. The core includes a volatile material. The shell includes a thermoplastic resin material. The metal film covers at least part of an outer surface of the microcapsule.

Non-aqueous electrolyte secondary battery having an intermediate layer comprising metal-covered microcapsules

A non-aqueous electrolyte secondary battery includes an electrode array and an electrolyte solution. The electrode array includes a positive electrode that includes a positive electrode current collector and a positive electrode composite material layer; a negative electrode that includes a negative electrode current collector and a negative electrode composite material layer; and a separator. The electrode array includes cellulose nanofibers. At least one of the peel strength between the positive electrode current collector and the positive electrode composite material layer and the peel strength between the negative electrode current collector and the negative electrode composite material layer is smaller than both the peel strength between the separator and the positive electrode composite material layer and the peel strength between the separator and the negative electrode composite material layer. The greater of the two peel strengths is at least 1.5 times greater than the smaller of the two.

Non-aqueous electrolyte secondary battery, and method of producing non-aqueous electrolyte secondary battery

Provided is a method for producing a negative electrode by using a negative electrode active material and ceramic particles, the method ensuring satisfactory coatability of the paste and high peel strength and hardness of the obtained negative electrode active material layer. The method for producing a negative electrode disclosed herein includes a step of coating a negative electrode paste including a negative electrode active material and ceramic particles on a negative electrode current collector; a step of drying the coated negative electrode paste to form a negative electrode active material layer; and a step of pressing the negative electrode active material layer. The ceramic particles have an aspect ratio of 1.5 or more and 20 or less. The ceramic particles have a short side length of &#x2155; or less of an average particle diameter of the negative electrode active material. In the negative electrode paste, the ceramic particles are contained in an amount of 3% by mass to 20% by mass based on a total solid content of the negative electrode paste.

Method for producing negative electrode and secondary battery, and secondary battery

The separator is used in a battery. The separator includes a porous film and a columnar filler. The porous film is made of resin. The columnar filler is made of insulating ceramic. The columnar filler is filled in the porous film. The axial direction of the columnar filler is in line with the thickness direction of the porous film.

Separator and non-aqueous electrolyte secondary battery

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.

Non-aqueous electrolytic secondary battery and method of manufacturing the same

A negative electrode for a non-aqueous electrolyte secondary battery of the present disclosure includes a negative electrode current collector, a negative electrode composite material layer formed on the surface of the negative electrode current collector. The negative electrode composite material layer includes a negative electrode active material containing silicon oxide and heat expandable microcapsules. The ratio of silicon oxide to the total amount of the negative electrode active material is 30 mass % or less. The blending ratio of the heat expandable microcapsules to the total amount of the negative electrode active material is 0.5 mass % or more. The ratio of the heat expandable microcapsules in contact with silicon oxide to the amount of the heat expandable microcapsules contained in the negative electrode composite material layer is 70 mass % or more.

Negative electrode and non-aqueous electrolyte secondary battery including the same

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.

Manufacturing method for non-aqueous electrolyte secondary battery

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.

Nonaqueous electrolyte secondary battery including a positive electrode having a positive electrode mixture layer including a first powder and a second powder

A method of manufacturing a non-aqueous electrolyte solution secondary battery includes: (A) preparing a first composite material by mixing a first positive electrode active material, a first conductive material and a first binder; (B) preparing a second composite material by mixing a second positive electrode active material, a second conductive material and a second binder; and (C) manufacturing a positive electrode by forming a positive electrode composite layer including the first composite material and the second composite material. The first positive electrode active material has an average discharge potential lower than that of the second positive electrode active material. The first conductive material has a first OAN. The second conductive material has a second OAN. A ratio of the second OAN to the first OAN is 1.3 or more and 2.1 or less. A sum of the first OAN and the second OAN is 31.64 ml/100 g or less.

Method of manufacturing non-aqueous electrolyte solution secondary battery and non-aqueous electrolyte solution secondary battery

A secondary battery includes a wound electrode assembly in which a positive electrode sheet, a negative electrode sheet and a separator are stacked and wound. The positive electrode sheet is provided with a long positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is disposed on the positive electrode current collector. The negative electrode sheet is provided with a long negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is disposed on the negative electrode current collector. The separator is interposed between the positive electrode sheet and the negative electrode sheet. The negative electrode current collector has a first active material layer-free region at one edge of the negative electrode current collector in a winding direction of an axis of the wound electrode assembly. The first active material layer-free region is a region where the negative electrode active material layer is not formed. The positive electrode current collector has a second active material layer-free region at one edge of the positive electrode current collector in a winding direction of an axis of the wound electrode assembly. The second active material layer-free region is a region where the positive electrode active material layer is not formed. The negative electrode current collector and the positive electrode current collector are disposed, with the first active material layer-free region and the second active material layer-free region being projected toward opposite sides in the winding direction of the axis of the wound electrode assembly. A width of the negative electrode active material layer is wider than a width of the positive electrode active material layer and a bacterial cellulose is disposed in at least a surface layer of the negative electrode active material layer that faces the second active material layer-free region.

Secondary battery

This invention provides a lithium secondary battery that comprises a positive electrode comprising a positive electrode active material layer and a negative electrode comprising a negative electrode active material layer. The positive electrode active material layer and the negative electrode active material layer are placed to face each other. The negative electrode active material layer has an area A comprising a non-positive-electrode-facing portion that does not face the positive electrode active material layer. The area A comprises a negative electrode active material, a hot-melt binder and a temperature-sensitive thickener. The hot-melt binder has a melting point and the temperature-sensitive thickener has a gelation temperature both in a range of 45&#xb0; C. to 100&#xb0; C.

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Moriguchi, Japan

Yuji Yokoyama