Nippon Steel Sumitomo Metal Corporation

Nippon Steel Corporation

Chuo Denki Kogyo Co., Ltd.

Nippon Steel Chemical & Material Co., Ltd.

Tsubakimoto Chain Company

Tatsuo Nagata

Sukeyoshi Yamamoto

Noriyuki Negi

Koji Moriguchi

Masahiro Fukuda

Naoki Fujimoto

Hiroto Unno

Hiroshi Yamamoto

Tooru Fujiwara

Takashi Fukuda

Takashi Nakagawa

Makoto Fujiwara

Yasuto Goto

Kiyokazu Ishizuka

Hiroki Ishida

Mitsuharu Yonemura

Akira Taniyama

Nobuo Kitao

Katsumasa Matsumoto

Shunsuke Taniguchi

Takafumi Amino

Akihiko Saguchi

Tomoyuki Kakeshita

Tomoyuki Terai

Ryutaro Nakamura

Satoshi Nakatou

A high-strength steel foil for the positive and negative electrode current collectors of nickel-hydrogen secondary batteries which uses a light weight and economical steel foil and which is thin and strong and has excellent rust resistance and resistance to metal ion leaching. Also, a high-strength steel foil for the positive and negative electrode current collectors of nickel-hydrogen secondary batteries which has excellent elongation. The Ni-plated steel foil for hydrogen secondary battery current collectors comprises, by mass %, C: 0.0001 to 0.0200%, Si: 0.0001 to 0.0200%, Mn: 0.005 to 0.300%, P: 0.001 to 0.020%, S: 0.0001 to 0.0100%, Al: 0.0005 to 0.1000%, N: 0.0001 to 0.0040%, one or both of Ti and Nb: 0.800% or less respectively, and a balance of Fe and impurities. The Ni-plated steel foil has an Ni plating layer on both surfaces. The thickness of the Ni plating layer on both surfaces of the Ni-plated steel foil is greater than or equal to 0.15 μm, the thickness of the Ni-plated steel foil is 5 to 50 μm, the tensile strength is over 400 MPa but no greater than 1200 MPa, and the surface defect area percentage is less than or equal to 5.00% for both surfaces of the Ni-plated steel foil.

Ni-plated steel foil for nickel-hydrogen secondary battery current collector, nickel-hydrogen secondary battery current collector, and nickel-hydrogen secondary battery

Provided is a negative electrode active material which is excellent in capacity, capacity retention ratio, and a coulombic efficiency when charging/discharging is repeated. The chemical composition of the alloy particles of the negative electrode active material of the present disclosure includes 0.50 to 3.00 mass % of oxygen, and alloy elements containing Sn: 13.0 to 40.0 at % and Si: 6.0 to 40.0 at %, with the balance being Cu and impurities. The structure of the alloy particles includes: one or more types selected from the group consisting of a phase having a D0structure, and a δ phase; one or more types selected from the group consisting of an ε phase and an η' phase; and a SiOphase (x=0.50 to 1.70). The SiOphase (x=0.50 to 1.70) has a volume fraction of 5.0 to 60.0% and the η′ phase has a volume fraction of 0 to 60.0%.

Negative electrode active material, negative electrode, and battery

The present invention has as its technical issue to secure not only mechanical strength but also conductivity by increasing the contact area with the positive electrode active substance or positive electrode mixture while also securing corrosion resistance to alkali or an electrolytic solution when applying stainless steel foil to a current collector for a positive electrode of a secondary battery so as to deal with the increasingly higher capacities and smaller sizes and lighter weights of lithium ion secondary batteries and has as its object the provision of a current collector for a positive electrode of a secondary battery using such stainless steel foil. The invention is a current collector comprised of stainless steel foil made to decrease in surface hardness while obtaining corrosion resistance by giving it a chemical composition decreased in Cr and containing a trace amount of Sn or a chemical composition containing Ti, a thickness of 1 μm or more and 20 μm or less, and a surface hardness of a Vickers hardness of Hv300 or less applied to a secondary battery positive electrode. When measuring an electrical contact resistance between the positive electrode active substance and the current collector after pressing, when the filling ratio of the positive electrode mixture is 74%, the electrical contact resistance is 100Ω or less. In particular, that effect is exhibited when the density of the positive electrode mixture is 3.0 g/cmor more (filling ratio: 50% or more).

Stainless foil current collector for secondary battery positive electrodes

A Ni-plated steel sheet according to one aspect of the present invention includes a base steel sheet; and a Ni plating layer provided on a surface of the base steel sheet, wherein the Ni plating layer includes a Ni—Fe alloy layer formed on the surface of the base steel sheet, and a ratio of a Sn content to a Ni content in the Ni plating layer is 0.0005% to 0.10%.

Ni-plated steel sheet and manufacturing method thereof

The negative electrode active material according to the present embodiment includes alloy particle containing an alloy component and oxygen of 0.50 to 3.00 mass %. The alloy component contains Sn: 13.0 to 40.0 at % and Si: 6.0 to 40.0 at %. The alloy particle contains: one or two phases selected from a D0phase in which the Si content is from 0 to 5.0 at % and a &#x3b4; phase in which the Si content is from 0 to 5.0 at %; one or two phases selected from an &#x3b5; phase in which the Si content is from 0 to 5.0 at % and an &#x3b7;' phase in which the Si content is from 0 to 5.0 at %; and an SiOx phase. The alloy particle has, in an X-ray diffraction profile, a peak having a largest integrated diffraction intensity in a range of 42.0 to 44.0 degrees of a diffraction angle 2&#x3b8;.

A negative electrode active material is provided that is utilized in a nonaqueous electrolyte secondary battery, and that can improve the capacity per volume and charge-discharge cycle characteristics. The negative electrode active material according to the present embodiment contains an alloy having a chemical composition consisting of, in at %, Sn: 13.0 to 24.5% and Si: 3.0 to 15.0%, with the balance being Cu and impurities. The alloy particles contain a phase with a peak of the most intense diffraction line appearing in a range of 42.0 to 44.0 degrees of a diffraction angle 2&#x3b8;, the most intense diffraction line being a diffraction line having the largest integrated diffraction intensity in an X-ray diffraction profile. A half-width of the most intense diffraction line of the alloy particles is in a range of 0.15 to 2.5 degrees.

Provided is a negative electrode active material that can improve the capacity per volume and charge-discharge cycle characteristics of a nonaqueous electrolyte secondary battery represented by a lithium ion secondary battery. The negative electrode active material according to the present embodiment contains an alloy phase. The alloy phase undergoes thermoelastic diffusionless transformation when releasing or occluding metal ions. The negative electrode active material of the present embodiment is used in a nonaqueous electrolyte secondary battery. Thermoelastic diffusionless transformation refers to so-called thermoelastic martensitic transformation.

Negative electrode active material

Provided is a negative electrode active material that can improve the discharge capacity per volume and charge-discharge cycle characteristics. The negative electrode active material according to the present embodiment contains an alloy phase. The alloy phase undergoes thermoelastic diffusionless transformation when releasing metal ions or occluding metal ions. The oxygen content of the negative electrode active material is not more than 5000 ppm in mass.

Negative electrode active material, negative electrode and battery

Provided is a negative electrode active material that can improve the discharge capacity per volume and charge-discharge cycle characteristics. The negative electrode active material of the present embodiment includes a powder material and an oxide layer. The powder material contains an alloy phase which undergoes thermoelastic diffusionless transformation when releasing metal ions or occluding the metal ions. The oxide layer is formed on the surface of the powder material, and has a thickness of not more than 10 nm.

Provided is a negative electrode active material which can improve discharge capacity per amount and charge-discharge cycle characteristics. The negative electrode active material of the present embodiment contains at least one of material A and material B, and material C:

Provided is a negative electrode active material that can improve the discharge capacity per volume and/or charge-discharge cycle characteristics. The negative electrode active material according to the present embodiment contains an alloy phase and ceramics. The alloy phase undergoes thermoelastic diffusionless transformation when releasing or occluding metal ions. The ceramics is dispersed in the metal phase. The content of ceramics in the alloy phase is more than 0 to 50 mass % with respect to the total mass of the alloy phase and the ceramics.

An inexpensive negative electrode material for a nonaqueous electrolyte secondary battery includes three types of powder materials: alloy material A; alloy material B; and a conductive material. Alloy material A includes a CoSnstructure containing Co, Sn, and Fe and has an Sn content of at least 70.1 mass % and less than 82.0 mass %. Alloy material B includes CoSnand has a lower discharge capacity than alloy material A. The proportion Rof the mass of alloy material B based on the total mass of alloy material A and B is greater than 5.9% and less than 27.1%. The content of the conductive material is at least 7 mass % and at most 20 mass % based on the total mass of alloy material A and B, and the conductive material. The exotherm starting temperature for the negative electrode material is less than 375.4&#xb0; C.

Negative electrode material for a nonaqueous electrolyte secondary battery and a method for its manufacture

The present invention provides a negative electrode material for a nonaqueous electrolyte secondary battery which can improve the cycle properties of a lithium ion secondary battery and a method for manufacturing the negative electrode material. The negative electrode material comprises at least two types of powdery alloy materials A and B in which powdery alloy material A contains Co, Sn, and Fe and does not contain Ti and powdery alloy material B contains Fe, Ti, and Sn, and the proportion of the mass of powdery alloy material B to the sum of the mass of powdery alloy material A and the mass of powdery alloy material B is at least 10 mass % and at most 30 mass %.

Negative electrode material for nonaqueous electrolyte secondary batteries and manufacturing method thereof

A negative electrode material provided by the present invention capable of suppressing a decrease in charge acceptance and high temperature storage properties in an electrode with a high capacity and a high density is a mixed carbon material comprising carbon material A having cores of graphite powder with amorphous carbon and/or turbostratic carbon adhered to or coated on the surface of the cores and carbon material B which is graphite powder, the compressibility which is the density (g/cm) of the material when 1.00 grams of the material are packed into a cylindrical mold with an inner diameter of 15 mm and compressed by applying a pressing force of 8.7 kN and reducing the pressing force to 0.15 kN is 1.60-1.78 g/cmfor carbon material A and 1.75-1.85 g/cmfor carbon material B, the compressibility of carbon material A is less than the compressibility of carbon material B, and the mixing ratio (carbon material A/carbon material B) is 1-9 as a mass ratio.

Mixed carbon material and negative electrode for a nonaqueous secondary battery

The present invention provides a mixed carbon material which comprises carbon material A and carbon material B and which is a carbon material suitable for a negative electrode material which can provide a nonaqueous secondary battery having a low irreversible capacity and having a negative electrode with a high capacity and high charge acceptance. Carbon material A and carbon material B both have cores made of graphite powder and a surface carbon material in the form of at least one of amorphous carbon and turbostratic carbon adhered to or coated on at least a portion of the surface of the graphite powder. The compressed density is 1.80-1.90 g/cmfor carbon material A alone, 1.45-1.65 g/cmfor carbon material B alone, and 1.75-1.84 g/cmfor the mixed carbon material.

Mixed carbon material including graphite powder cores and surface carbon material on a surface thereof and negative electrode for nonaqueous secondary battery

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Ikeda, Japan

Tatsuo Nagata