Matsushita Electric Industrial Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Sumitomo Electric Industries, Limited

Toyota Jidosha Kabushiki Kaisha

Other

Sumitomo Electric Industries, Co.

Panasonic Corporation

Kiyoshi Hayashi

Nobuyasu Morishita

Munehisa Ikoma

Hiroki Takeshima

Keizo Harada

Fumio Kato

Hideo Kaiya

Shosaku Yamanaka

Kenichi Watanabe

Yasushi Nakamura

Hideaki Ohyama

Shinichi Sumiyama

Katsuyuki Tomioka

Kojiro Ito

Toshihiro Yamada

Akiko Okabe

Yukihiro Okada

Hiromu Matsuda

Yoshinori Toyoguchi

Shinichi Yuasa

Kazuhiro Ohta

Jun Matsumura

Masakazu Ikeyama

A positive electrode for alkaline storage batteries that enables to improve the active material utilization rate, while suppressing the self-discharge. The positive electrode for alkaline storage batteries includes a support having conductivity, and a positive electrode active material adhering to the support. The positive electrode active material includes particles of a nickel oxide. The particles of the nickel oxide include a first particle group having a particle diameter of 20 &#x3bc;m or more, and a second particle group having a particle diameter of less than 20 &#x3bc;m. The first particle group includes a first component with cracks, and a second component without cracks. The proportion of the first particle group in the particles of the nickel oxide is 15 vol % or more, and the proportion by number of the first component in the first particle group is 15% or more.

Positive electrode for alkaline storage batteries and alkaline storage battery

Provided is a positive electrode for an alkaline storage battery, capable of achieving a high charge efficiency over a wide range of temperature including high temperatures. The positive electrode includes a positive electrode material mixture including: a nickel oxide as a positive electrode active material; a first additive; and a second additive differing from the first additive. An amount of sulfate ions SOremaining in the nickel oxide is 0.45 mass % or less. The first additive is a compound including at least one selected from the group consisting of ytterbium, indium, calcium, barium, beryllium, antimony, erbium, thulium, and lutetium. The second additive is a compound including at least one selected from the group consisting of titanium, vanadium, scandium, niobium, zirconium, and zinc.

Positive electrode for alkaline storage battery and alkaline storage battery using the same

Disclosed is an alloy powder for electrodes for nickel-metal hydride storage batteries having a high battery capacity and being excellent in life characteristics and high-temperature storage characteristics. The alloy powder includes a hydrogen storage alloy containing elements L, M, Ni, Co, and E. L includes La as an essential component. L includes no Nd, or when including Nd, the percentage of Nd in L is less than 5 mass %. The percentage of La in the hydrogen storage alloy is 23 mass % or less. M is Mg, Ca, Sr and/or Ba. A molar ratio &#x3b1; to a total of L and M is 0.045&#x2264;&#x3b1;&#x2264;0.133. A molar ratio x of Ni to the total of L and M is 3.5&#x2264;x&#x2264;4.32, and a molar ratio y of Co is 0.13&#x2264;y&#x2264;0.5. The molar ratios x and y, and a molar ratio z of E to the total of L and M satisfy 4.78&#x2264;x+y+z&#x3c;5.03.

Alloy powder for electrodes, negative electrode for nickel-metal hydride storage batteries including the same, and nickel-metal hydride storage battery including the same

Provided is an alloy powder for an electrode which enables an alkaline storage battery to have both excellent discharge characteristics and excellent life characteristics. The alloy powder includes a hydrogen storage alloy including an element L, Mg, Ni, Al, and an element M. The element L is at least one selected from the group consisting of group 3 elements and group 4 elements of the periodic table (excluding Y). The element Mis at least two selected from the group consisting of Ge, Y, and Sn. A molar proportion x of Mg in a total of the element L and Mg is 0.008&#x2266;x&#x2266;0.54. A molar proportion y of Ni, a molar proportion &#x3b1; of Al, and a molar proportion &#x3b2; of the element M, per the foregoing total is 1.6&#x2266;y&#x2266;4, 0.008&#x2266;&#x3b1;&#x2266;0.32, and 0.01&#x2266;&#x3b2;&#x2266;0.12, respectively.

Alloy powder for electrode, negative electrode for alkaline storage battery using the same, and alkaline storage battery

An alkaline storage battery includes: a cylindrical case having a side wall including an opening end portion and a bottom; a sealing plate; a gasket interposed between the sealing plate and the opening end portion; and a sealant between the gasket and the opening end portion. The side wall has an annular groove opened at an outer surface thereof, and an inwardly curl portion at the opening end portion. In at least part of the groove, the minimum width L1 is within 0.2 mm. The sealant includes a polyamide resin formed such that when two test-plate materials are bonded together at bonding faces facing each other via a bonding portion of the sealant, and moved in parallel with the bonding faces and in opposite directions to have a relative displacement within 0.5 to 5 mm, a stress at least 0.02 N/mmis applied to the bonding portion.

Cylindrical alkaline storage battery

To provide an alkaline storage battery, a cobalt compound obtained by mixing a cobalt hydroxide powder and a sodium hydroxide powder and applying a heat treatment to the same in an atmosphere containing oxygen, a cobalt compound obtained by adding a sodium hydroxide aqueous solution and an aqueous solution containing an oxidizing agent to a cobalt hydroxide powder, or a cobalt compound obtained by baking a cobalt hydroxide powder in an atmosphere containing oxygen is used. This provides cobalt compounds suitable for producing long-life and highly reliable alkaline storage batteries, methods for manufacturing the same, and positive electrode plates of alkaline storage batteries employing the same.

Cobalt compound for use in alkaline storage battery, method for manufacturing the same, and positive electrode plate of alkaline storage battery employing the same

A positive electrode plate for alkaline storage battery that does not swell very much even after repeated charge-discharge cycles and can be manufactured easily, a method for manufacturing the same, and an alkaline storage battery using the same are provided. A conductive support (nickel foam) and an active material (nickel hydroxide particles) that is supported by the support are provided. An intermediate part of a positive electrode plate has a larger porosity than surface parts thereof.

Positive electrode plate for alkaline storage battery and method for manufacturing the same, and alkaline storage battery using the same

A positive electrode for an alkaline storage battery having a high capacity and facilitating the manufacturing thereof and an alkaline storage battery using the same are provided. The positive electrode utilized includes active material powder containing nickel hydroxide and powder made of cobalt compounds, where a ratio of a cobalt compound with a valence of cobalt being 2.6 or more to the whole of cobalt compounds is 30 weight % or more.

Disclosed is an active material for constituting a nickel electrode for alkaline storage batteries which has a high utilization at high ambient temperatures and therefore realizes a battery of higher energy density and a longer cycle life. The nickel electrode active material comprises a nickel hydroxide powder prepared from nickel sulfate and contains SO at 0.4 wt % or less in the crystal of the powder. The nickel hydroxide is preferably solid solution nickel hydroxide incorporating therein at least one element selected from the group consisting of cobalt, cadmium, zinc and magnesium.

Nickel electrode active material for alkaline storage batteries and nickel electrode using the same

The instant specification discloses a method for producing nickel hydroxide from an aqueous solution containing an ammonium ion and dissolved nickel hydroxide in an alkaline state, which is characterized in that pH of the solution is controlled by supplying a hydroxide ion generated by water electrolysis thereto. The method of the invention is an environmentally friendly one for producing nickel hydroxide, which enables an easy control of physical properties of nickel hydroxide.

Method for producing nickel hydroxide

Disclosed is a nickel positive electrode which can best utilizes the effects of plural additives and exhibits a high capacity and a long cycle life. The nickel positive electrode contains a nickel hydroxide powder and a plurality of additives including cobalt oxide and a secondary additive, the secondary additive being encapsulated in a capsule of cobalt oxide.

Nickel positive electrode for alkaline storage batteries and method for producing the same

A battery electrode substrate which is constituted of a porous metallic body structure having communicating pores at a porosity of at least 90% and an Fe/Ni multilayer structure wherein the skeletal portion of the porous metallic body is composed mainly of Fe and has an Ni covering layer on the surface thereof while pores communicating with the inside and outside of Fe skeletal portion exist in the Fe skeletal portion and the inside of the pores is covered with Ni. The electrode substrate is produced by applying an iron oxide powder of at most 20 .mu.m in an average particle size on a porous resin core body; heat treating the core to remove an organic resin component while simultaneously sintering Fe to obtain a porous Fe body; and then covering the Fe skeletal portion with Ni by electroplating. In this process, the iron oxide can be used in combination with carbon powder. Further, a nickel porous sintered body can also be produced using nickel oxide in place of iron oxide.

Battery electrode substrate and process for producing the same

For providing an alkaline storage battery having a high energy density in a broader temperature range, the charge efficiency of a nickel positive electrode at the time of charging at high temperatures is enhanced by incorporating verbium and at least two elements selected from the group consisting of yttrium, and ytterbium in the form of a compound those and further at least one element selected from the group consisting of lanthanum, praseodymium, neodymium, samarium, gadolinium, terbium, dysprosium, holmium, thulium, cerium, promethium, europium, and lutetium in the form of a compound into a positive electrode paste containing a major component of nickel oxide as an active material.

Nickel positive electrode and alkaline storage battery using the same

In the paste type nickel positive electrode prepared by filling pores of a metal nickel plaque made of three-dimensional high porous sheet, or coating both sides or one side of a plaque made of either perforated nickel sheet or nickel plated steel sheet, with a paste type active material mainly composed of nickel hydroxide, by adding particles of cobalt hydroxide having the specific surface area of at least 10 m.sup.2 /g, average particle size of 1.7 microns or more, and content of fine particles with particle size of 1.0 micron or less of 20% or less, the utilization of positive electrode active material is enhanced, and by using this nickel positive electrode, the alkaline rechargeable battery, in particular, the nickel-metal hydride alkaline battery is enhanced in capacity and extended in service life.

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Neyagawa, Japan

Kiyoshi Hayashi