VRLA battery



A valve regulated lead-acid (VRLA) battery is a starved electrolyte AGM (absorbent glass mat) type battery and has a safety valve which prevents excessive build up of gas pressure inside the battery. Valve-regulated lead acid batteries rely upon internal gas recombination to minimize electrolyte loss over the life of the battery, thereby eliminating the need for re-watering. A lead-acid battery has lead positive plates, lead oxide negative plates, and an electrolyte which is a solution of sulfuric acid and distilled water. The plates and the plate separator material between them are arranged in plate packs in plate compartments. A valve regulated lead acid battery comprises separators and plates stacked within a sealed container, in which an electrolyte in a cell is retained in the pores of the separators and both of positive and negative electrode plates so as not to flow. VRLA recombination batteries offer a number of advantages compared to flooded cell batteries. The starved acid design of the battery facilitates the oxygen recombination reaction. The recombination reactions are facilitated by the starved acid or electrolyte condition where the electrolyte is immobilized in glass separaors disposed between the plates of the battery. VRLA batteries are particularly suited for remote back-up power applications because they do not require the same type of periodic maintenance required by flooded cells. These differing maintenance requirements provide cost savings when VRLA batteries are used.