MEETING EUROPEAN REQUIREMENTS WITH ADVANCED DESIGNS OF VALVE-REGULATED LEAD-ACID-BATTERIES

Valve-regulated lead/acid (VRLA) batteries now meet the majority of requirements for stand-by applications. There are two principal technologies for VRLA batteries; (i) cells with gelled electrolyte and (ii) cells with absorptive glass-mat (AGM) separators. New developments in both of these areas are described. Tubular-plate cells using gelled electrolyte offer many advantages over conventional counterparts and extend the available capacity range of VRLA batteries. New types of VRLA batteries using AGM separators have also been developed in larger capacity ranges and offer improvements in high-rate performance. For smaller capacities, recent achievements in the capability of batteries using pure lead plates will be compared with cast-alloy plates. These offer better high-rate performance and other unique advantages for a number of critical applications. All of these developments are set in the context of the relevant standards, and the importance of correct specification to ensure overall system reliability is discussed. VRLA batteries have evolved rapidly in recent years and continuing development will ensure that increased demands for standby power can be met.