Abstract: Electrode plate assemblies (41a, 41b, 41c) forming independent elements for electromotive force each contained in a partition member (46) are series-connected and accommodated in a battery case (45). Each element is constructed as a nickel-metal hydride rechargeable battery cell and has an electromotive force of 1.2V, and so the battery connected in series has an output voltage of 3.6V and can be applied to general purpose uses.

Abstract: An alkaline storage battery, a positive electrode material for the alkaline storage battery, and a method of preparation for the positive electrode material are disclosed. The positive electrode material is made up of nickel hydroxide particles that have cobalt oxyhydroxide on their surface. The particles may be prepared by a process in which &agr;-cobalt hydroxide adhered to the surface of the nickel hydroxide particles is oxidized to cobalt oxyhydroxide. The battery has a superior rate of utilization of active material, cycle life, and discharge characteristics.

Abstract: An electrochemical device comprising an electrolyte and at least one electrode plate, the electrochemical device having a metal part constituting the electrode plate or being connected to the electrode plate; the electrolyte comprising a solute and a solvent dissolving the solute; the metal part having an insulating oxide layer for preventing the electrolyte from creeping on at least part of the surface of the metal part.

Abstract: Disclosed is an alkaline storage battery comprising: a positive electrode comprising nickel hydroxide; a negative electrode; and an electrolyte layer interposed between the positive electrode and the negative electrode. The electrolyte layer comprises a water absorbent polymer and an aqueous alkaline solution. The water absorbent polymer is obtained by saponification of a copolymer comprising 100 parts by weight of monomer (A) and 0.01 to 10 parts by weight of monomer (B). The monomer (A) has at least one group capable of being converted to a carboxyl group by saponification and has one polymerizable double bond, and the monomer (B) has two or more polymerizable double bonds.

Abstract: The following steps are conducted: preparing a metal salt carried-substrate A by soaking a sintered nickel substrate in an acidic solution containing cobalt ions and at least one metal ions of magnesium ions, iron ions and manganese ions, and drying thus soaked substrate; preparing a hydroxide carried-substrate B by soaking the substrate A in an alkaline solution to deposit cobalt hydroxide and at least one metal hydroxide of magnesium hydroxide, iron hydroxide and manganese hydroxide in the pores and on the surface of the substrate A; obtaining an oxide carried-substrate C by oxidizing the cobalt hydroxide to produce cobalt oxide having a mean cobalt valence of over 2; and obtaining an active material carried-substrate D by soaking the substrate C in a solution containing nickel nitrate dissolved therein, drying thus soaked substrate C, and then soaking thus dried substrate C in an alkaline solution, to fill the active material in the substrate C.

Abstract: The present invention provides an alkaline storage battery which is superior in the rate of utilization of the active material, cycle life, and discharge characteristic through a more simplified way of preparation of a high-performance positive active material by addition of a smaller quantity of a cobalt compound than conventional methods. The alkaline storage battery is obtained by employing an active material prepared by rendering &agr;-type cobalt hydroxide adhere on the surface of nickel hydroxide particles and then treating with an aqueous solution of sodium hypochlorite in the positive plate.