Abstract: A housing for containing electrode assemblies and an electrolyte includes a cover 18 having a pair of long-side ends 18e. Peripheral thinned portions 11 are formed by cutting the inner face of a top plate 18a near the long-side ends 18e in parallel with the long-side ends 18e. A central thinned portion 15 is formed by cutting the central part of the outer face of the top plate 18a in parallel with the long-side ends 18e. This facilitates the rupture of a housing 1 due to an increase of the inner pressure, while ensuring the strength of the housing 1 to withstand external pressure.

Abstract: A separator for alkaline batteries which is obtained by bonding 5.0 to 45.0 g/m2 of a highly hygroscopic macromolecular compound of the crosslinking type having carboxyl group to a wetlaid nonwoven fabric comprising an alkali-resistant fiber, followed by crosslinking the macromolecular compound, wherein a silicate compound is added to the highly hygroscopic macromolecular compound of the crosslinking type in an amount of 1.0×10?4 to 10 mg/cm2 per unit area of the separator. By adding the silicate compound, absorption of the electrolyte is increased, the electrolyte can be held for a long time, the electric resistance of the separator itself can be kept small, growth of dendrite can be suppressed, short circuit due to the formed dendrite can be prevented, the volume of the negative electrode material can be increased by suppressing the thickness of the separator after absorbing the electrolyte, impact of dropping can be endured, and oxidative degradation in the alkaline dry cells can be suppressed.

Abstract: In a battery casing, there are accommodated a positive electrode containing manganese dioxide, a negative electrode containing zinc, and an electrolyte containing an aqueous solution of potassium hydroxide. The negative electrode contains bismuth of 100 ppm or less. In an AA dry battery, the amount of zinc in the negative electrode is 4.00 g or more, and the weight of the electrolyte is 4.00 g or more. In an AAA dry battery, the amount of zinc in the negative electrode is 1.71 g or more, and the weight of the electrolyte is 1.77 g or more.

Abstract: An AA alkaline dry battery includes a bottomed cylindrical casing of which internal volume is 6.25 ml or larger and which accommodates a positive electrode containing manganese dioxide of 9.30 g or more, a negative electrode containing zinc, and electrolyte containing an aqueous solution of potassium hydroxide of which concentration is 33.5 wt % or lower; a sealing member sealing the casing; and a negative electrode current collector extending from the sealing member into the negative electrode. The dry battery has, as discharge characteristics in the middle rate current discharge (AA dry batter), discharge duration until the battery voltage becomes 0.9 V is 9.3 hours or longer where discharge at 250 mA is performed at 25° C. for one hour per day.

Abstract: A separator for alkaline batteries which is obtained by bonding 5.0 to 45.0 g/m2 of a highly hygroscopic macromolecular compound of the crosslinking type having carboxyl group to a wetlaid nonwoven fabric comprising an alkali-resistant fiber, followed by crosslinking the macromolecular compound, wherein a silicate compound is added to the highly hygroscopic macromolecular compound of the crosslinking type in an amount of 1.0×10?4 to 10 mg/cm2 per unit area of the separator. By adding the silicate compound, absorption of the electrolyte is increased, the electrolyte can be held for a long time, the electric resistance of the separator itself can be kept small, growth of dendrite can be suppressed, short circuit due to the formed dendrite can be prevented, the volume of the negative electrode material can be increased by suppressing the thickness of the separator after absorbing the electrolyte, impact of dropping can be endured, and oxidative degradation in the alkaline dry cells can be suppressed.

Abstract: A high-quality alkaline dry battery with small variation in the internal resistance having suppressed variations in the heights of positive electrode mixture pellets in a manufacturing process is provided. In an alkaline dry battery including: at least one hollow cylindrical positive electrode mixture pellet containing manganese dioxide and graphite; a gel negative electrode containing zinc; and a separator interposed between the positive electrode mixture pellet and gel negative electrode; manganese dioxide containing at least manganese dioxide particles having a particle diameter of 10 ?m or less of 25 to 35% and manganese dioxide particles having a particle diameter of 60 to 100 ?m of 15 to 25% in a particle size distribution based on volume is used.

Abstract: In order to provide a positive electrode material mixture for an alkaline battery, the positive electrode material mixtures having small weight variations, a granulated mixture with favorable fluidity is used which comprises graphite and a positive electrode active material containing at least one of manganese dioxide and nickel oxyhydroxide, and has an angle of repose of 20 to 43 degrees.

Abstract: A manganese dry battery includes an anode zinc can made of a zinc alloy containing 0.001-0.5 wt. % of titanium and at least one element selected from the group consisting of 0.001-0.05 wt. % of indium and 0.001-0.05 wt. % of bismuth, or a zinc alloy further containing 0.01-0.4 wt. % of lead. Even without heavy metals such as Hg and Cd, the zinc alloy anode can has a corrosion-resistant property and mechanical strength equivalent to or greater than those of the conventional zinc anode can, thereby giving a low pollution zinc-carbon battery having a storage characteristic equivalent or superior to that of the conventional zinc anode can.