Abstract: The present invention relates to a lead-acid battery Comprising a positive and a negative electrode, each having a current collector comprising an expanded grid, characterized in that at least one of the positive electrode and the negative electrode contains an organic binder in an active material layer at an edge portion thereof. This makes it possible to suppress an internal short circuit resulting from the separation or abnormal growth of an active material due to repeated charge/discharge, thereby remarkably prolonging the cycle life of a lead-acid battery.

Abstract: The present invention relates to a lead-acid battery Comprising a positive and a negative electrode, each having a current collector comprising an expanded grid, characterized in that at least one of the positive electrode and the negative electrode contains an organic binder in an active material layer at an edge portion thereof.

Abstract: The present invention provides a process for producing a grid for use in lead acid batteries which comprises superposing, on a sheet bar of a lead-calcium alloy, a sheet or a foil of a lead-silver-tin alloy consisting of 0.01-1.0% by weight of tin and a residual quantity of lead and having a thickness smaller than that of the sheet bar, pressure-bonding both the materials by cold rolling to prepare an elementary sheet, and subjecting the elementary sheet to an expanding process or a punching process.The grid obtained according to the process of the invention is improved in the charge-discovery characteristics after overdischarging and standing and does not deteriorate the maintenance-free characteristic of lead-calcium-tin alloy.

Abstract: A paste type lead storage battery having a grid constituted by a grid base formed of a lead-calcium alloy and a layer of lead-antimony-stannum alloy roll-bonded integrally to the grid base on at least one side thereof. Preferably, the grid is formed by expanding a sheet of base material to which the alloy layer is integrally roll-bonded. Portions of the base and the alloy layer that serve as a active material support are both in contact with a paste-like active material, and antimony and stannum coexist in the alloy layer. The charge restoration after standing in a discharged state and the lifetime during cycles of charge and discharge including heavy discharge are thereby improved.

Abstract: The present invention provides a process for producing a grid for use in lead acid batteries which comprises superposing a sheet or a foil of a lead alloy on a sheet bar composed of a lead-calcium alloy, said sheet or foil of lead alloy having a composition different from that of the sheet bar and having a thickness smaller than that of the sheet bar, followed by integrating the two materials by cold rolling process to form an elementary sheet and then subjecting the elementary sheet to an expanding or punching processing.The grid obtained according to this process is improved in the charging recovery characteristics after standing in a superdischarged state and in the corrosion resistance of grid at high temperatures without deteriorating the maintenance-free characteristics of the lead-calcium alloy itself.

Abstract: A method for fabricating an electrode for use in lead storage batteries in which an aqueous emulsion of a silicone capable of forming an elastic, porous matrix on breaking of the emulsion, is contacted with a finely divided active electrode material at the stage of preparing an electrode paste, or after formation as an electrode. The contacted material is dried, so that the elastic, porous silicone matrix formed in association with and in intimate contact with the finely divided active electrode material. An aqueous dispersion of fluorocarbon resin can be further added to the paste, or an electrode having a fibrous network of fluorocarbon resin can be applied with the silicone emulsion. Fine particles obtained from the silicone emulsion can also be applied to a finely divided active electrode material.