A battery 2 includes: a container 10; and an electrode group 6 housed in the container 10 together with an alkaline electrolyte liquid 4. The electrode group 6 includes a nickel electrode 14 as a positive electrode and a negative electrode 12 that are combined with a separator 8 interposed therebetween. The nickel electrode 14 includes a positive electrode core and a positive electrode mixture permeated in the positive electrode core. The positive electrode mixture contains nickel hydroxide that is a positive electrode active material. The nickel hydroxide contains a sulfate salt, and a weight rate of a S component contained in the sulfate salt to a Ni component in the nickel hydroxide is 0.28% or more and 1.50% or less.

A green secondary electrode includes a conductive substrate, active material and material additives in direct contact with the conductive substrate, and a combination of vinyl acetate-ethylene and methylcellulose-based additive binding the conductive substrate, active materials, and material additives together. The green secondary electrode may be a positive electrode or a negative electrode.

An electrode has a band-shaped core and an electrode mixture layer carried by the core to form a spiral electrode assembly with a gas generating electrode and a separator for an alkaline secondary battery. The electrode in the spiral shape has a first circumference portion, an intermediate portion, and an outermost circumference portion. The first circumference portion is a starting portion for winding into the spiral shape. The intermediate portion is a second and following circumferences of the spiral shape. The outermost circumference portion has an inner surface only which faces the gas generating electrode. The electrode mixture layer includes a reactant that develops a reaction consuming gas generated from the gas generating electrode. An amount of the reactant in the first circumference portion is more than those in the intermediate portion and/or the outermost circumference portion.

A nickel-metal hydride secondary battery includes an outer can and a group of electrodes housed in the outer can together with an alkaline electrolytic solution. The group of electrodes includes a positive electrode and a negative electrode that are superposed with a separator interposed therebetween, and the negative electrode includes a hydrogen absorbing alloy for nickel-metal hydride secondary batteries, the hydrogen absorbing alloy having a single composition and composed of a plurality of crystal phases.

An alkaline storage battery includes a spiral electrode group in which a positive electrode plate, a negative electrode plate, and a separator arranged between the positive electrode plate and the negative electrode plate are laminated, the negative electrode plate is located on the inner peripheral side of the positive electrode plate at an innermost peripheral portion, and an electrically conductive outer packaging can in which the spiral electrode group is accommodated together with an alkaline electrolytic solution. The negative electrode plate includes a negative electrode core body, a first negative electrode mixture layer carried on a surface on the outer peripheral side of the negative electrode core body, and a second negative electrode mixture layer carried on a surface on the inner peripheral side of the negative electrode core body. The negative electrode core body has a burr protruding toward the outer peripheral side at an edge portion of an innermost peripheral portion of the negative electrode core body. The thickness of the edge portion of an innermost peripheral portion of the first negative electrode mixture layer is smaller than the thickness of a portion other than the edge portion of the first negative electrode mixture layer. The height of the burr is 30% or less of the thickness of the separator.

A battery includes an outer can, and an electrode group that is accommodated in the outer can together with an alkaline electrolyte solution, in which the electrode group includes a positive electrode and a negative electrode superposed with a separator being interposed therebetween, the positive electrode includes a positive electrode core and a positive electrode mixture packed in the positive electrode core, the positive electrode mixture includes a nickel hydroxide powder that is an aggregate of a particle of nickel hydroxide as a positive electrode active material, and a conductive material, the conductive material is a high-valent cobalt compound provided with a high valence and having a valence of higher than three, the high-valent cobalt compound containing sodium, and the conductive material is in an amount of 0.5 parts by mass or more and 5.0 parts by mass or less based on 100 parts by mass of the positive electrode active material.

A nickel-metal hydride secondary battery is provided with: an outer package can having an opening at an upper end; an electrode group accommodated in the outer package can together with an alkaline electrolyte; and a sealing body that seals the opening of the outer package can. The sealing body includes a cover plate having a central through hole, and a valve element made of an elastic material to close the central through hole. The valve element includes a cylindrical main body part having a base end surface that covers the central through hole, and an extended diameter part positioned on an opposite side of the main body part from the base end surface and having a diameter made larger than a diameter of the main body part. A ratio R of a thickness T of the extended diameter part to a total height H of the valve element is equal to or higher than 27%.

A battery comprises an electrode group including a separator, a positive electrode and a negative electrode. The negative electrode comprises a negative electrode core, negative electrode mixture layers retained to the negative electrode core, and a fluorine resin layer disposed on the surface of the negative electrode mixture layers. The negative electrode mixture layers include a first outermost peripheral region located at the outermost periphery of the electrode group and a second outermost peripheral region located opposite to the first outermost peripheral region. When the amount of the fluorine resin constituting a first fluorine resin layer in a portion of the first outermost peripheral region is represented by A, and the amount of the fluorine resin constituting a second fluorine resin layer in a portion of the second outermost peripheral region is represented by B, a relation A>B is satisfied.

A nickel-hydrogen secondary battery includes an electrode group which contains a positive electrode, a negative electrode, and a separator, wherein the negative electrode includes a negative electrode core, and a negative electrode mixture layer held by the negative electrode core, wherein the negative electrode mixture layer contains a fluororesin; a quantity of the fluororesin, expressed by a mass applied per unit area of the negative electrode, is within a range of 0.2 mg/cm.sup.2 or more and 2.0 mg/cm.sup.2 or less; and a fluororesin content which is a ratio of the fluororesin contained in a unit volume of the negative electrode mixture layer is higher in an inner layer portion than in an outer layer portion in the negative electrode mixture layer.

Provided is an aqueous battery configured to use hydroxide ions (OH.sup.−) as carrier ions. The aqueous battery is an aqueous battery comprising a cathode layer, an anode layer and an aqueous liquid electrolyte, wherein the cathode layer contains, as a cathode active material, a graphite having a rhombohedral crystal structure; wherein the anode layer contains, as an anode active material, at least one selected from the group consisting of an elemental Zn, an elemental Cd, an elemental Fe, a Zn alloy, a Cd alloy, an Fe alloy, ZnO, Cd(OH).sub.2, Fe(OH).sub.2 and a hydrogen storage alloy; and wherein, as an electrolyte, at least one selected from the group consisting of KOH and NaOH is dissolved in the aqueous liquid electrolyte.