An alkaline electrochemical cell includes a cathode, an anode which includes an anode active material, and a non-conductive separator disposed between the cathode and the anode, wherein from about 20% to about 50% by weight of the anode active material relative to a total amount of anode active material has a particle size of less than about 75 m, and wherein the separator includes a unitary, cylindrical configuration having an open end, a side wall, and integrally formed closed end disposed distally to the open end.

An alkaline dry cell includes a bottomed cylindrical cell case, a positive electrode packed in the cell case and is made of a stack of n pieces of hollow cylindrical pellets, a negative electrode disposed in a hollow portion of the pellets, a separator interposed between the positive electrode and the negative electrode, and an alkaline electrolytic solution. A thickness of a body portion of the cell case is 0.08 to 0.16 mm. n is an integer of 3 or more. An average density d.sub.m of manganese dioxide in the n pellets is 2.80 to 3.00 g/cm.sup.3. A density of manganese dioxide of at least one pellet positioned in a middle portion in a height direction of the stack is 2.75 g/cm.sup.3 or less.

A battery can forming steel plate that configures an electrode can (a positive electrode can) of an alkaline battery and is to be formed into a battery can by presswork, the steel plate as a base material includes an iron and nickel diffusion layer or an iron and nickel-cobalt alloy diffusion layer that is formed by forming a nickel plated layer or a nickel-cobalt alloy plated layer with a thickness of 0.5 to 2.0 m on an inner surface of a battery can of a steel plate (base material steel plate) as a base material, and subsequently performing heat diffusion treatment on the nickel plated layer or the nickel-cobalt alloy plated layer. An average number of crystal grains per 0.25 mm.sup.2 unit area of the steel plate as the base material is equal to or more than 12.3.

An alkaline dry battery includes a bottomed cylindrical battery case; a positive electrode packed in the battery case and including n hollow cylindrical pellets; a negative electrode disposed in a hollow portion of the pellets; a separator interposed between the positive electrode and the negative electrode; and an alkaline electrolytic solution. The positive electrode includes manganese dioxide and a conductive agent, n is an integer of 1 or more, and an average density of manganese dioxide of the positive electrode is 2.80 to 3.00 g/cm.sup.3. The density d.sub.c of manganese dioxide in the center portion in the height direction of the positive electrode is 98% or less of an average value d.sub.e of density of manganese dioxide in each of both end portions.

Various embodiments are directed to an electrochemical cell having a non-homogeneous anode. The electrochemical cell includes a container, a cathode forming a hollow cylinder within the container, an anode positioned within the hollow cylinder of the cathode, and a separator between the cathode and the anode. The anode defines a characteristic gradient between an interior portion of the anode and the outermost surface of the anode adjacent the separator. The characteristic gradient may be defined as, for example, an average active material particle size within the anode that changes as a function of the radial location within the anode or a surfactant concentration gradient that changes as a function of the radial location within the anode.

An alkaline dry cell includes a bottomed cylindrical cell case, a positive electrode packed in the cell case and is made of a stack of n pieces of hollow cylindrical pellets, a negative electrode disposed in a hollow portion of the pellets, a separator interposed between the positive electrode and the negative electrode, and an alkaline electrolytic solution. A thickness of a body portion of the cell case is 0.08 to 0.16 mm. n is an integer of 3 or more. An average density d.sub.m of manganese dioxide in the n pellets is 2.80 to 3.00 g/cm.sup.3. A density of manganese dioxide of at least one pellet positioned in a middle portion in a height direction of the stack is 2.75 g/cm.sup.3 or less.

Alkaline electrochemical cells are provided, wherein dissolved zinc oxide or zinc hydroxide is included at least in the free electrolyte solution, and/or solid zinc oxide or zinc hydroxide is included in the anode, so as to slow formation of a zinc oxide passivation layer on a zinc electrode. Methods for preparing such cells are also provided.

An alkaline dry cell includes a positive electrode, a negative electrode, and an alkaline electrolyte solution. The negative electrode includes a terephthalic acid compound and a negative electrode active material containing zinc. The terephthalic acid compound is terephthalic acid having an electron-withdrawing substituent or a salt thereof. The electron-withdrawing substituent is, for example, at least one selected from the group consisting of Br, F, and Cl. The terephthalic acid compound preferably includes terephthalic acid having one electron-withdrawing substituent or a salt thereof.

A gelled anode for an alkaline electrochemical cell contains zinc-based particles, an alkaline electrolyte, a gelling agent, and two or more additives selected from the group consisting of an alkali metal hydroxide, an organic phosphate ester surfactant, a metal oxide, and tin, which as reduced cell gassing properties relative to cells lacking such additives.

As a battery can forming steel plate that configures an electrode can (a positive electrode can) of an alkaline battery and is to be formed into a battery can by presswork, the steel plate as a base material includes an iron and nickel diffusion layer or an iron and nickel-cobalt alloy diffusion layer that is formed by forming a nickel plated layer or a nickel-cobalt alloy plated layer with a thickness of 0.5 to 2.0 m on an inner surface of a battery can of a steel plate (base material steel plate) as a base material, and subsequently performing heat diffusion treatment on the nickel plated layer or the nickel-cobalt alloy plated layer. An average number of crystal grains per 0.25 mm.sup.2 unit area of the steel plate as the base material is equal to or more than 12.3.