Patent ID: 6274275
Filing Date: 2001-08-14
Classification: B22F,C25D,H01M,Y02E,Y02P,Y10T

Abstract:
An alkali storage cell employing as a generating element a coiled electrode assembly composed of a positive electrode, a negative electrode, and a separator provided between the electrodes, said positive electrode comprising a spongelike porous metal substrate in which an active material comprising nickel hydroxide is retained, said porous metal substrate produced by filling a metal into an organic polymer having a porous sponge structure and thereafter baking the metal-retaining polymer, said porous metal substrate characterized in that:a carbon content of said porous metal substrate is set at 0.5 wt. % or lower;said porous metal substrate has a multiplicity of three-dimensional voids each surrounded by a lattice having a longer length and a shorter length;a ratio of a segment of said longer length to a segment of said shorter length is greater than 1 and less than or equal to 1.7, where said segment of said longer length is approximately parallel to a surface of said porous metal substrate and said segment of said shorter length crosses said segment of said longer length approximately at a right angle, andsaid segment of said longer length is directed to a direction approximately parallel to a direction in which said coiled electrode assembly is wound.