Abstract: An electrode includes an expanded grid and an active material provided on the grid, the thickness of the grid is the same as the strand and connecting sections of the strand, presenting a waveform as a whole. When this grid is used in the electrode as a current collector, the connecting sections are located near the center of the thickness direction of the electrode and strand are arranged by projecting upward and downward, respectively, from the boundary where the connecting sections are situated. Accordingly, a lead-acid storage battery having long life characteristics is made available.

Abstract: The present invention provides a lead acid storage battery keeping sufficient cycle life even under vibrating conditions. The lead acid storage battery of the present invention includes an assembly element that is obtained by alternately laying positive electrode plates, each positive electrode plate having an expanded grid, and negative electrode plates, each negative electrode plate being accommodated in a bag-like separator, one upon another. The separator is provided by folding a fine porous synthetic resin sheet and sealing left and right overlapping sides of the folded sheet to have a bag-like shape. The separator has a plurality of vertical ribs that are formed in parallel to one another on an outer surface of the separator and that are located in a central portion of the separator occupying a most part of its width. The separator further has small rib areas that extend along a length of the bag-like separator and that are arranged on left and right sides thereof.

Abstract: A lead-acid storage battery uses as a current collector an expanded grid produced by processing a belt shaped material formed of lead or lead alloys. Strand of a grid for negative electrodes have a twist. The extent of the negative electrode's grid is larger than that of the positive electrode's grid. Accordingly, degradation of output characteristics in the domain deep in the depth of discharge is prevented and further high rate discharge cycle life characteristics are improved.

Abstract: Highly oxidized lead powder containing red lead not more than 90% is efficiently produced by maturing the lead powder material at a low temperature section of a furnace keeping the temperature less than 100.degree. C. by spraying water to the material and then, by heating the same from 400.degree. to 500.degree. C. at a high temperature section of the furnace. The highly oxidized lead powder produced in this method is preferable as active material of a lead storage battery, that is, a paste preparation and formation treatment become easy and a long life electrode is obtained.

Abstract: A battery plate for lead acid storage batteries using a grid prepared by expanding a lead-calcium-tin (Pb--Ca--Sn) alloy sheet, is made by expanding a Pb--Ca--Sn alloy sheet having a tensile strength of 6.0 kg/mm.sup.2 or lower and an Sn content of 0.6-1.8% by weight to make a grid,filling this grid with an active material paste, and then aging the grid to increase the tensile strength of the expanded grid to 7.0 kg/mm.sup.2 or higher. The workability in expanding of the Pb--Ca--Sn alloy sheet can be improved and furthermore, concentration of stress strain on the nodes of the grid can be inhibited and thus, corrosion of the nodes can be inhibited. The aging can provide a battery pate having a high tensile strength and a lead acid storage battery having an excellent charge-discharge cycle life characteristics.

Abstract: This invention relates to a method and apparatus to continuously manufacture red lead which is a primary material used to produce storage batteries, anticorrosion paint, glass, etc. In this method, lead monoxide and metal lead powder are continuously supplied from an inlet of a rotating inner cylinder which acts as a reaction chamber of a rotary kiln. The powder mixture proceeds toward the outlet of the kiln while it is oxidized into red lead. The yield of red lead, and the stable oxidation of raw material into red lead, can be accomplished by returning a part of the product powder available at the outlet to the inlet of the kiln.

Abstract: This invention relates to a method of producing a paste-type electrode for a lead storage battery which comprises packing into an active material support a paste prepared by kneading a lead oxide having a conversion ratio to red lead (Pb.sub.3 O.sub.4) of 90% or less or a mixture of this lead oxide powder with water and sulfuric acid as the principal components. Because this lead oxide contains red lead less than 90%, red lead formed on the surface of this oxide and lead oxide (PbO) formed in the particle core are directly bonded. This enhances the bonding power between the active materials. The paste-type electrode prepared by this method provides high adhesion of the paste to the active material support and high bonding power between the active materials. Therefore, both improvements in life and in efficiency of formation charge can be attained.