Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Matsushita Electrical Industrial Co., Ltd.

Yoshitaka Dansui

Kohji Yuasa

Futoshi Tanigawa

Tatsuhiko Suzuki

Fumio Kato

Hideki Kasahara

Yasushi Nakamura

Hideaki Ohyama

Kyoko Nakatsuji

Kenji Suzuki

Yoichi Izumi

Naomi Arita

Masumi Katsumoto

Akihiro Maeda

Kazutaka Ikeda

Chiaki Iwakura

Takeshi Yao

Shinichi Orimo

Sugao Fujinaga

Naoji Furukawa

Hironori Ura

Sadaaki Yokoo

Hai-Wen Li

Hiroko Sakai

Hiroko Takado

Michio Hirota

Susumu Kikuyama

Yuko Nakamori

Kouji Yuasa

A negative electrode active material for a nickel-metal hydride battery of the present invention includes a hydrogen storage alloy, the hydrogen storage alloy containing La, Mg, Ni, Co, Al, and element M. The molar ratio y of Ni to the total of La and Mg is 2&#x2266;y&#x2266;3, the molar ratio z of Co to the total of La and Mg is 0.25&#x2266;z&#x2266;0.75, the molar ratio &#x3b1; of Al to the total of La and Mg is 0.01&#x2266;&#x3b1;&#x2266;0.05, and the molar ratio x of Mg to the total of La and Mg is 0.01&#x2266;x&#x2266;0.5. Element M represents at least one selected from the group consisting of Y and Sn, and the content of element M in the hydrogen storage alloy is 0.4 wt % or less.

Negative electrode active material for nickel-metal hydride battery and nickel-metal hydride battery using the same, and method for treating negative electrode active material for nickel-metal hydride battery

A negative electrode material for a nickel-metal hydride battery containing a hydrogen-absorbing alloy represented by a general formula: MmTNiAlMnCoT, in which: Mm is at least one of light rare earth elements; Tis at least one selected from the group consisting of Mg, Ca, Sr and Ba; Tis at least one selected from the group consisting of Sn, Cu and Fe; and 0.015&#x2266;a&#x2266;0.5, 2.5&#x2266;x&#x2266;4.5, 0.05&#x2266;y+z&#x2266;2, 0&#x2266;b&#x2266;0.6, 0&#x2266;c&#x2266;0.6 and 5.6&#x2266;x+y+z+b+c&#x2266;6 are satisfied.

Negative electrode material for nickel-metal hydride battery and treatment method thereof, and nickel-metal hydride battery

An electrode alloy powder includes a hydrogen storage alloy and magnetic material clusters. The hydrogen storage alloy contains 20 to 70 wt % of Ni. The magnetic material clusters contain metal nickel, and have an average cluster size of 8 to 10 nm. A method for producing the electrode alloy powder includes an activation step of allowing a raw material powder including a hydrogen storage alloy to be in contact with an aqueous solution containing A wt % of sodium hydroxide and held at 100&#xb0; C. or greater for B minutes. A and B satisfy 2410&#x2266;A&#xd7;B&#x2266;2800.

Alloy powder for electrode and method for producing same

An alkaline storage battery includes, as main constituent elements, a positive electrode having nickel hydroxide as an active material, a negative electrode, a separator, and an electrolyte made of an aqueous alkali solution, and a foamed three-dimensional porous substrate composed of nickel as a main component is used as a core substrate of the positive electrode, and the weight ratio of this core substrate in the positive electrode is set to 30% to 50%, thereby allowing both electron conductivity and ion conductivity of the positive electrode, with long life and high output even under severe conditions.

Alkaline storage battery

An alkaline storage battery includes: a positive electrode containing nickel hydroxide; a negative electrode; a separator layer intervening between the positive electrode and the negative electrode; and an alkaline electrolyte. The separator layer includes a water-absorbing polymer, a water repellent, an alkaline aqueous solution, and a scavenger capable of trapping an element which leaches from the negative electrode into the alkaline aqueous solution. The scavenger comprises an oxygen-containing metal compound. The negative electrode is a hydrogen storage alloy electrode, a cadmium electrode or a zinc electrode. The water-absorbing polymer comprises a cross-linked polymer having at least one kind of monomer unit selected from the group consisting of an acrylate unit and a methacrylate unit.

Alkaline storage battery and method for producing the same

A nickel metal hydride storage battery having an excellent charging efficiency at high temperatures is provided by using a positive electrode comprising nickel hydroxide particles and at least one rare earth compound obtainable by treating a rare earth oxide with an aqueous alkaline solution and an oxidizing agent.

Method of preparing a nickel positive electrode active material

The paste type positive electrode of the present invention contains a first active material and a second active material. The first active material comprises X parts by weight of particulate nickel hydroxide with aX/100 parts by weight of cobalt oxyhydroxide carried thereon. The second active material comprises Y parts by weight of particulate nickel oxyhydroxide, of which an oxidation number of nickel is &#x3b1;, with bY/100 parts by weight of cobalt oxyhydroxide carried thereon. Here, all the following relations are satisfied: (1) 2.5&#x2266;&#x3b1;&#x3c;3.0, (2) 0.01&#x2266;(aX/100+bY/100)/(X+Y)&#x2266;0.20, (3) 0&#x3c;b&#x2266;a&#x2266;10 or 0=b&#x3c;a&#x2266;10, and (4) 2.1&#x2266;(2X+&#x3b1;Y)/(X+Y)&#x3c;2.2.

Paste type positive electrode for alkaline storage battery, and nickel-metal hydride storage battery

A battery pack comprises: a battery unit ( ) including a plurality of batteries ( ) arranged flatly and electrically connected with one another by either series or parallel connection, or a combination thereof; a pair of heat transfer plates ( ) made of a material exhibiting excellent thermal conductivity and arranged in parallel to a surface where the battery unit ( ) is arranged, of which one makes surface contact with a top-surface side of each of the batteries ( ) of the battery unit ( ), and the other makes surface contact with a back-surface side of each of the batteries ( ) of the battery unit ( ); and a housing ( ) made of a material exhibiting excellent thermal conductivity, the housing accommodating the battery unit ( ) and the pair of heat transfer plates ( ) and making surface contact with the pair of heat transfer plates ( ).

Battery pack

A battery pack suppresses temperature rise of secondary battery during charging and discharging. The battery pack includes a plurality of batteries stacked up, a case enclosing the plurality of batteries, a heat collector disposed near the battery positioned in the center of the plurality of batteries, a heat radiator placed at one side of the case, and a first heat transfer unit placed for connecting the heat collector and heat radiator. Further, the battery pack includes a heat transfer plate placed at the other side of the case, and a second heat transfer unit placed between the heat collector and heat transfer plate.

Battery pack and power tool using the same

By using a thin film-formed positive electrode, and negative electrode and a film separator, the capacity density of the electrode plate can be improved and at the same time a nickel-hydrogen secondary battery with a higher capacity can be easily obtained; as a result a nickel-hydrogen secondary battery with a higher capacity density can be provided.

Nickel-hydrogen secondary battery and process for producing electrode therefor

An alkaline storage battery using positive electrodes comprising an active material containing nickel hydroxide particles and a rare earth element or a compound thereof containing or mixed with 0.1-100 ppm of Fe or an Fe compound based on the rare earth element or the compound thereof is provided.

Alkaline storage battery and positive electrode used for the alkaline storage battery

The method for producing a positive electrode active material for an alkaline storage battery is disclosed. The method includes a first oxidation treatment of a raw material powder comprising a nickel hydroxide solid solution and cobalt hydroxide to oxidize the cobalt hydroxide to a cobalt oxyhydroxide; and a second oxidation treatment of the powder obtained in the first oxidation treatment to oxidize the nickel hydroxide solid solution to a nickel oxyhydroxide solid solution.

Method for producing a positive electrode active material for an alkaline storage battery

A nickel-metal hydride secondary battery includes positive electrodes including nickel hydroxide, negative electrodes including a hydrogen-absorbing alloy, separators and an alkaline electrolyte. The positive electrode includes a compound silicate. By employing the above construction, the compound silicate reacts with Mn or Al which dissolves out from the negative electrode to inhibit deterioration of electrochemical characteristics of the battery, and thus the life of the battery can be prolonged.

Nickel-metal hydride secondary battery comprising a compound silicate

The present invention provides alkaline storage batteries high in energy density and excellent in overdischarge resistance, and, besides, less in decrease of capacity even if charging and discharging cycle is repeated at high temperatures. There is used a positive electrode comprising a foamed nickel substrate having the number of pores of 80-160 pores/inch (PPI ) and a thickness of skeleton of 30-60 &mgr;m in which spherical nickel hydroxide solid solution particles having an average particle size of 5-20 &mgr;m and a cobalt oxide conductive agent having an average particle size of 1 &mgr;m or less and mainly composed of &ggr;-cobalt oxyhydroxide having a cobalt valence of higher than 3.0 are held and the total occupying ratio of the spherical nickel hydroxide solid solution particles and the cobalt oxide conductive agent based on the whole electrode plate is in the range of 75-85 vol %.

Non-sintered positive electrode for alkaline storage battery and alkaline storage battery using the same

The present invention provides a positive electrode material for alkaline storage batteries which has high energy density and causes little capacity reduction even when a charge/discharge cycle is repeated at high temperatures. The positive electrode material for alkaline storage batteries of the present invention comprises nickel hydroxide particles and a layers of cobalt oxide coating the nickel hydroxide particles. A valence of cobalt of the cobalt oxide is greater than 3.0, and the cobalt oxide contains sodium ions or potassium ions inside the crystal and further fixes lithium hydroxide or lithium ions.

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Fujisawa, Japan

Yoshitaka Dansui