The Lead-Acid Battery is a sacrificial design with unavoidable degradation over time. The inside of a battery cell is a highly chemically active environment.
Lead is soft, so in order to make the plates more rigid, in most of the early designs, antimony was added as a hardening agent. The percentage of antimony was high, in some cases up to 12%. The downside was that the higher the percentage of antimony caused increased hydrogen evolution which resulted in water loss which increased with battery age and resulted in more maintenance.
This paper will discuss the problems associated with ageing of Lead-Acid batteries.