Direct cast lead alloy strip for expanded metal battery plate grids

摘要

A method of making a lead alloy grid for use in a plate for a lead acid battery that enables thin battery plates with a high surface area. The method of the present invention includes forming the lead alloy, such as by direct casting, to a very small thickness, then work hardening the cast strip to create a grid by forming indentations and protrusions in the thinly cast alloy strip, which in addition to strengthening the strip, provides a desirable surface topography for paste adhesion and interface characteristics. The work hardening, for example embossing, may further include splitting the strip at a high point of the protrusions and indentations to create perforated protrusions and indentations. The grid may then be used to make a plate by pasting an active mass onto the grid, steaming the pasted grid, and curing the pasted grid to provide a plate having a thickness of about 0.05 inch or less. There is further provided a lead alloy grid for use in a plate of a lead acid battery, the grid comprising a cast lead-tin-calcium alloy having spaced protrusions and indentations on each opposing surface of the grid. The protrusions and indentations may further include a perforation. The grid has a higher surface area than punched or expanded grids, thereby providing a lower resistance and better adherence at the paste/grid interface.