Method for making positive grids and lead-acid and batteries using such grids

Abstract

A method for making positive grids for lead-acid batteries from calcium-tin-silver lead-based alloys comprises casting an alloy strip and then rolling the strip at a temperature between about the solvus temperature and the peritectic temperature of the alloy, quenching the rolled strip, then, preferably, heat aging at a temperature of 200° F. to 500° F., and fabricating into the positive grid, such grids having enhanced mechanical and high temperature corrosion resistance characteristics.

I claim:  
     
         1 . A lead-acid battery comprising positive and negative plates and a separator positioned between said positive and negative plates, said positive plates having a grid of an alloy comprising about 0.025% to 0.065% calcium, about 0.4% to 1.9% tin, about 0.02% to 0.045% silver, and the remainder lead, the percentages being by weight of the alloy, said grid being of an alloy strip rolled at a temperature from about the solvus temperature up to less than the peritectic temperature of the alloy composition.  
     
     
         2 . The battery of claim  9  wherein the rolled strip has been heat-aged at a temperature of about 200° F. to 500° F. for a time to increase the population of special grain boundaries in the rolled strip.