LEADY OXIDE FOR LEAD ACID BATTERY POSITIVE PLATES - SCOPE FOR IMPROVEMENT/

Among the many factors that determine and influence the performance of lead/acid batteries, one of the most important, and as yet not fully developed, is how to make the positive active mass more electrochemica lly reactive. The inherent characteristics of this active mass are the cumulative result of the four precursor stages of its production, nam ely, the leady oxide, paste mixing, curing and formation procedures. T here is evidence to suggest that the method of pasting itself is also influential. Many recent studies have reported progress on techniques to increase active-material utilization, to improve plate conditioning , and to solve the vexagious problem of premature capacity loss. The p urpose of this discussion is to focus attention on the role and the im portance of leady oxide on battery design and performance. At present, the battery industry makes leady oxide by either the ball-mill or the Barton-pot process. It is difficult to conclude which of the two meth ods gives the best leady oxide. Each type of leady oxide has its champ ions but, in general, ball-mill and Barton-pot product both make effec tive automotive batteries. For deep-cycle batteries, however, many bat tery companies (especially in Europe and Japan) prefer ball-mill oxide ; in North America, the Barton-pot variety is favoured. This investiga tion examines the present procedures for making leady oxide, the desir able properties of leady oxide, and the influence of the oxide on batt ery performance. Analysis shows that there is scope for the production of improved leady oxide - by using existing production techniques and /or by the development of new processing technology.