Abstract: An alkaline secondary battery is capable of inhibiting an increase of internal pressure in the charging/discharging cycles and extending life of charging/discharging cycles. This secondary battery comprises, a case, a paste-type positive electrode accommodated in the case and essentially consisting of a conductive substrate filled with a paste containing an active material and a binder, a negative electrode accommodated in the case, a separator interposed between the positive electrode and the negative electrode, and an alkaline electrolyte accommodated in the case, wherein the binder in the positive electrode contains a copolymer consisting of a vinyl alcohol unit and a unit having COOX group, wherein X is an element selected from the group consisting of hydrogen, alkaline metals and alkaline earth metals.

Abstract: This invention discloses an alkali secondary battery which includes a cadmium-free positive electrode whose swelling ratio is decreased, and in which the cycle characteristic is improved and the charge efficiency in use at high temperatures is also improved. This alkali secondary battery includes a positive electrode accommodated in a case and having a structure in which a paste containing nickel hydroxide grains, a conductor, and a binder is filled in a metal porous body, a negative electrode accommodated in the case and so arranged as to oppose the positive electrode with a separator sandwiched between them, and an alkali electrolyte contained in the case. The nickel hydroxide grains contained in the positive electrode have a structure in which cobalt and at least one transition metal selected from the group consisting of copper, bismuth, chromium, gallium, indium, lanthanum, scandium, and yttrium are coprecipitated with metal nickel at a ratio of 1.5 to 11.0 wt % with respect to nickel hydroxide.

Abstract: There is provided a paste-type electrode for an alkali secondary cell which can suppress occurrence of internal short-circuiting, which is likely to happen when an electrode is rolled along with another electrode having the opposite polarity and a separator interposed therebetween. The paste-type electrode for an alkali secondary cell comprises a three-dimensional substrate including a felt-like metal porous member in which a plurality of hollow metal fibers are arranged three-dimensionally, diameters of those of the metal fibers arranged near the surface portion of the porous member being greater than those arranged in the inner portion, an average diameter of those of the metal fibers near the surface portion being in a range of 20 to 150 .mu.m, and an average diameter of those of the metal fibers in the inner portion being in a range of 10 to 100 .mu.m, and paste containing an activation substance filled in the three-dimensional substrate.

Abstract: There is provided a paste-type electrode for an alkali secondary cell which can suppress occurrence of internal short-circuiting, which is likely to happen when an electrode is rolled along with another electrode having the opposite polarity and a separator interposed therebetween. The paste-type electrode for an alkali secondary cell comprises a three-dimensional substrate including a felt-like metal porous member in which a plurality of hollow metal fibers are arranged three-dimensionally, diameters of those of the metal fibers arranged near the surface portion of the porous member being greater than those arranged in the inner portion, an average diameter of those of the metal fibers near the surface portion being in a range of 20 to 150 .mu.m, and an average diameter of those of the metal fibers in the inner portion being in a range of 10 to 100 .mu.m, and paste containing an activation substance filled in the three-dimensional substrate.

Abstract: There is provided a paste-type electrode for an alkali secondary cell which can suppress occurrence of internal short-circuiting, which is likely to happen when an electrode is rolled along with another electrode having the opposite polarity and a separator interposed therebetween. The paste-type electrode for an alkali secondary cell comprises a three-dimensional substrate including a felt-like metal porous member in which a plurality of hollow metal fibers are arranged three-dimensionally, diameters of those of the metal fibers arranged near the surface portion of the porous member being greater than those arranged in the inner portion, an average diameter of those of the metal fibers near the surface portion being in a range of 20 to 150 .mu.m, and an average diameter of those of the metal fibers in the inner portion being in a range of 10 to 100 .mu.m, and paste containing an activation substance filled in the three-dimensional substrate.