Abstract: A method for producing a nickel metal-hydride storage battery includes: (i) assembling a battery by enclosing the positive electrodes, the negative electrodes, separators, and an electrolyte in a case; (ii) charging the battery with electric current in a range of 0.05 C (ampere) to 0.2 C (ampere) until a state of charge rises to a range of 10% to 30%; (iii) overcharging the battery that has been subjected to the charging, with electric current in a range of 0.2 C (ampere) to 1 C (ampere), and thereafter discharging the same until the state of charge lowers to 10% or below; and (iv) subjecting the battery after overcharging to a plurality of charging-discharging cycles, each charging-discharging cycle being composed of charging the battery that has been subjected to the overcharging, with electric current in a range of 0.2 C (ampere) to 5 C (ampere) until the state of charge rises to a range of 60% to 95%, and discharging the same until a battery voltage lowers to a range of 0.70 V to 1.05 V.

Abstract: A battery which has undergone initial charging and discharging is placed inside a sealed vessel, which is evacuated by a vacuum pump. After this evacuated state has been maintained for a while, the density of hydrogen gas within the sealed vessel is measured by a hydrogen density sensor, based on which the presence or absence of a gas escape from the battery is determined. The battery may be heated instead of subjecting it to charging and discharging.

Abstract: A method for producing a nickel metal-hydride storage battery includes: (i) assembling a battery by enclosing the positive electrodes, the negative electrodes, separators, and an electrolyte in a case; (ii) charging the battery with electric current in a range of 0.05 C (ampere) to 0.2 C (ampere) until a state of charge rises to a range of 10% to 30%; (iii) overcharging the battery that has been subjected to the charging, with electric current in a range of 0.2 C (ampere) to 1 C (ampere), and thereafter discharging the same until the state of charge lowers to 10% or below; and (iv) subjecting the battery after overcharging to a plurality of charging-discharging cycles, each charging-discharging cycle being composed of charging the battery that has been subjected to the overcharging, with electric current in a range of 0.2 C (ampere) to 5 C (ampere) until the state of charge rises to a range of 60% to 95% , and discharging the same until a battery voltage lowers to a range of 0.70 V to 1.05 V.

Abstract: In a method of inspecting batteries for short circuit failures, an electrode plate group 1 composed of positive and negative electrode plates 2, 3 with intervening separators 4 interposed therebetween is set on a pressing station 7, where it is compressed during short-circuiting inspection is performed, for simulating a state wherein separators are compressed by swelling electrode plates 2, 3 during charging and discharging of battery.

Abstract: In a method of inspecting batteries for short circuit failures, an electrode plate group 1 composed of positive and negative electrode plates 2, 3 with intervening separators 4 interposed therebetween is set on a pressing station 7, where it is compressed during short-circuiting inspection is performed, for simulating a state wherein separators are compressed by swelling electrode plates 2, 3 during charging and discharging of battery.

Abstract: A battery which has undergone initial charging and discharging is placed inside a sealed vessel, which is evacuated by a vacuum pump. After this evacuated state has been maintained for a while, the density of hydrogen gas within the sealed vessel is measured by a hydrogen density sensor, based on which the presence or absence of a gas escape from the battery is determined. The battery may be heated instead of subjecting it to charging and discharging.

Abstract: 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.

Abstract: 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.

Abstract: An improved non-sintered type nickel positive electrode comprising a nickel hydroxide powder as an active material and a cobalt hydroxide powder for improving the utilization of the active material, and an alkaline storage battery configured with the positive electrode are disclosed. In the non-sintered type nickel positive electrode, at least part of the surfaces of the particles of the cobalt hydroxide powder is covered with a stabilizing agent of at least one member selected from the group consisting of a higher carboxylic acid, an ester of carboxylic acid, an aldehyde, a phenol and a vitamin.