Lead-Acid Battery: Techniques for Bonding the Positive Plates

The purpose of this article is to discuss the bonding of the positive plates of the new lead-acid battery to form a complete battery cell. The negative plates are bonded by a center-pour technique described elsewhere in this issue. Figure 1 shows part of one element of the new battery, using an early prototype positive-plate design. During assembly, negative plates are stacked between positive plates until the element is complete; typically ten or more negatives are used. Each circular positive plate has four or more pure-lead lugs. These must be bonded to the corresponding lugs on the adjacent positive plates. At the bottom of Fig. 1 are two unpasted positive plates after bonding with a pasted negative plate in position. Note that the battery lugs in this early design were flat to facilitate bonding studies. Figure 2 shows a pair of lugs cut out of the battery plates. This is a later design using curved lugs, approximately 0.188 inch thick and 2.25 inches long and formed out of pure lead. It is desirable to use curved lugs to provide a maximum cross section of the lug, maximum electrical conductance, and simplest overall geometry. Two new concepts of fusion bonding were developed. Both are to be 1419