DEVELOPMENT OF A VALVE-REGULATED LEAD-ACID-BATTERY FOR AUTOMOTIVE USE

The use of valve-regulated lead/acid batteries (VRLA) in automotive applications provides some important advantages with respect to traditional flooded designs. Difficulties are reported for flooded lead/acid batteries that use Pb-Ca alloys in the positive grids with respect to recovery of capacity after deep discharge. This problem is no longer valid for recombinant batteries using absortive glass-mat (AGM) separators. Further, this truly maintenance-free battery can be installed in any position, even outside the engine compartment, because of the absence of gas emission or electrolyte spillage. The shelf life is very long and the battery can be stored at open circuit for 12 months with no significant loss of performance. The cold-cranking capacity is higher than the equivalent conventional lead/acid battery due to the reduced internal resistance.